- Email: [email protected]
A Polymerase Chain Reaction–Based Algorithm to Detect and Prevent Transmission of Adenoviral Conjunctivitis in Hospital Employees
A Polymerase Chain Reaction–Based Algorithm to Detect and Prevent Transmission of Adenoviral Conjunctivitis in Hospital Employees IRENE C. KUO, COLLEEN ESPINOSA, MICHAEL FORMAN, AND ALEXANDRA VALSAMAKIS PURPOSE:
To devise and implement a practice algorithm that would enable rapid detection and appropriate furlough of hospital employees with adenoviral conjunctivitis in order to prevent healthcare-associated epidemic keratoconjunctivitis. DESIGN: Evaluation of an ongoing quality assurance/ improvement initiative. METHODS: Employees of Johns Hopkins Hospital with signs and symptoms of adenoviral conjunctivitis underwent evaluation by nurse practitioners in Occupational Health and rapid diagnostic testing by real-time polymerase chain reaction (PCR). Sequencing was used to determine serotype when adenovirus was detected. Signs, symptoms, diagnosis, and disposition of employees with eye complaints as well as PCR and serotype results were recorded. RESULTS: Over a 36-month period approximately 18% of initial employee visits were due to unique, eyerelated complaints. Viral conjunctivitis was suspected in 542 of 858 employees with eye complaints (62%); adenovirus was detected by PCR in 44 of 542 suspected viral conjunctivitis cases (8%) or 44 of 858 employees with any eye concern (5%). Fourteen of the 44 employees had adenoviral serotypes and clinical presentation consistent with epidemic keratoconjunctivitis (type 37 [n [ 6], 8 [n [ 4], 4 [n [ 3], 19 [n [ 1]). Other serotypes found in individuals with less severe conjunctivitis were 3 (n [ 5), 4 (n [ 5), 56 (n [ 4), 1 (n [ 2), 42 (n [ 1), and 7 (n [ 1). No healthcareassociated adenoviral conjunctivitis outbreaks occurred after algorithm implementation, and fewer employees required furlough than had clinical diagnosis alone been used. CONCLUSIONS: The algorithm is an effective infection prevention tool that minimizes productivity loss compared to clinical diagnosis and allows for determination of prevalence and serotype characterization of adeno-
Supplemental Material available at AJO.com. Accepted for publication Dec 4, 2015. From the Wilmer Eye Institute, Department of Ophthalmology, The Johns Hopkins University School of Medicine (I.C.K.); and the Division of Occupational and Environmental Medicine (C.E.) and Division of Medical Microbiology, Department of Pathology (M.F., A.V.), The Johns Hopkins Hospital, Baltimore, Maryland. Inquiries to Irene C. Kuo, Wilmer Eye Institute, 4924 Campbell Blvd #100, Baltimore, MD 21236; e-mail: [email protected]
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viral conjunctivitis in hospital employees. (Am J Ophthalmol 2016;163:38–44. Ó 2016 by Elsevier Inc. All rights reserved.)
A
DENOVIRAL EYE INFECTION IS A PUBLIC HEALTH
concern, with manifestations ranging from selflimited conjunctivitis to prolonged ocular morbidity in the case of epidemic keratoconjunctivitis (EKC). Some adenoviral infections, however, may not be easily distinguishable from EKC at presentation; the 3 other clinical scenarios are nonspecific follicular conjunctivitis, pharyngeal conjunctival fever, and acute hemorrhagic conjunctivitis. EKC is most commonly caused by serotypes 8, 19, and 371; less typical serotypes associated with EKC are 4,2 53, and 54.3 EKC is more clinically obvious and induces more morbidity than the other adenoviral eye conditions and is associated with a longer disease course and significant injection, chemosis, and keratitis that can impair vision.4,5 Outbreaks in hospitals and eye clinics result in substantial morbidity and lost productivity.6–12 In response to healthcare-associated EKC outbreaks,6–12 one of which resulted in the temporary closure of a large eye institute,12 a ‘‘red-eye room,’’ where persons with potentially infectious conjunctivitis could be triaged and isolated, was established in 1990 in the Wilmer Eye Institute Emergency Room (ER), Department of Ophthalmology, at the Johns Hopkins Hospital (JHH).13 This arrangement was part of an infection prevention program consisting of ophthalmic instrument decontamination, hand hygiene, use of single-dose eye drops, and employee furloughs.14 When institutional changes led to the permanent closure of the Wilmer ER and the red-eye room at the end of January 2008, a multidisciplinary team composed of a cornea specialist and stakeholders in infection prevention, employee health, and the clinical virology/molecular infectious disease clinical diagnostic laboratory was convened in order to devise and implement a new practice algorithm for preventing healthcareassociated transmission of adenoviral eye disease. Twentymonth pilot data have been published.14 Here we report 36-month data on adenovirus detection rates and the results of adding serotype determination to this infection prevention practice algorithm as applied to healthcare workers with red eye.
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0002-9394/$36.00 http://dx.doi.org/10.1016/j.ajo.2015.12.007
METHODS THE INSTITUTIONAL REVIEW BOARDS OF JOHNS HOPKINS
Medicine ruled that publishing of an evaluation of this quality improvement initiative did not require approval as it ‘‘does not involve human subjects research under the Department of Health and Human Services or Food and Drug Administration regulations.’’ The new red-eye employee practice algorithm, which is in effect at all times, is shown in Figure 1. It consists of initial evaluation by nurse practitioners in the Occupational Health clinic and rapid diagnostic testing by realtime polymerase chain reaction (PCR) in individuals with signs and symptoms consistent with adenoviral conjunctivitis. The Occupational Health clinic sees employees with health concerns that arise during work hours and may impinge on their ability to work. In order to limit the possibility of transmission within the clinic, employees seeking red-eye evaluation are required to call ahead to make an appointment. A corneal specialist taught nurse practitioners in the Occupational Health clinic to recognize signs and symptoms of probable viral conjunctivitis (vs conditions like suspected corneal abrasion or subconjunctival hemorrhage) and how to collect swab specimens of the inferior conjunctival fornix.14 The nurse practitioners were instructed to swab only when viral conjunctivitis was suspected. Swabs (polyester, Dacron, or rayon with plastic or aluminum shafts) were placed in M4 medium and sent at room temperature for PCR testing performed daily at the JHH Clinical Virology/Molecular Infectious Disease Diagnostic Laboratory. Screening criteria included duration of symptoms, presence of viral prodrome, discharge or tearing, and unilateral onset. Employees with suspected viral conjunctivitis were evaluated, swabbed, and discharged home within 30 minutes of intake. Nurse practitioners notified employees of PCR results and furlough status by 8 PM if specimens were received in the laboratory by 3 PM. If adenovirus was detected by PCR, a 2-week furlough was invoked. Direct sequencing of specimens found to contain adenovirus DNA was performed retrospectively for epidemiologic purposes—to determine the proportion of employees infected with EKCassociated adenoviral serotypes (most typically types 8, 19, and 37).15–21 Toward the end of the furlough, the nurse case manager in the Occupational Health clinic contacted employees with adenoviral conjunctivitis by phone to assess symptoms and to schedule a follow-up examination at Occupational Health that was required before return to duty. Furlough was continued if symptoms and signs of conjunctivitis persisted, given probable infectious potential. Employees were sent to the Department of Ophthalmology for consultation for conditions the nurse practitioners deemed an emergency; symptoms including but not limited to persis-
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tent redness, tearing, pain, and blurred vision; or conditions in which the nurse practitioners were unsure of diagnosis. ADENOVIRAL DETECTION AND SEROTYPE DETERMINA14 TION: As described in the pilot study, PCR for adeno-
virus in conjunctival specimens of employees was developed and validated in the Johns Hopkins Hospital molecular microbiology diagnostic laboratory. ‘‘Total nucleic acid was isolated from conjunctival specimens (processed volume, 400 microliters) using automated instrumentation (BioRobot M48, using Virus Mini Protocol, version 1.1 software and MagAttract Virus Mini M48 reagents [Qiagen, Germantown, MD];’’14 elution volume, 125 mL). Adenovirus DNA was detected by real-time PCR (primers: 59 -GCC ACG GTG GGG TTT CTA AAC TT-39 , 59 -GCC CCA GTG GTC TTA CAT GCA CAT C-39 ; fluorogenic probe FAM 59 -TGC ACC AGA CCC GGG CTC AGG TAC TCC GA-39 TAMRA)22 using 7500 Real Time PCR instruments (Life Technologies, Carlsbad, California, USA). The analytical sensitivity (95% detection rate or limit of detection) is 300 copies/mL, and the assay detects at least 16 adenovirus serotypes, including strains from 6 of 7 adenovirus serogroups (A-F). When adenoviruses were detected, serotype was determined by nested PCR of the hexon gene hypervariable regions 1–623 using previously extracted total nucleic acid (outer primers: AdhexF1 (19135-19160) 59 -TIC TTT GAC ATI CGI GGI GTI CTI GA-39 / AdhexR1 (20009-20030) 59 -CTG TCI ACI GCC TGR TTC CAC A-39 ; inner primers: AdhexF2 (19165-19187) 59 -GGY CCY AGY TTY AAR CCC TAY TC-39 / AdhexR2 (19960-19985) 59 -GGT TCT GTC ICC CAG AGA RTC IAG CA-39 ) followed by bidirectional Sanger sequencing using AdhexF2/AdhexR2 as sequencing primers in reactions containing BigDye Terminator v.3.1 (Life Technologies). Sequencing was performed on either a 3100 or a 3500 Genetic Analyzer (Life Technologies). These reagents correctly identified 50 prototype strains; serotypes 15 and 29 have identical sequences in the queried region, cannot be distinguished,23 and therefore are reported as 15/29. The ability to identify serotypes associated with ocular disease (8, 19, 37) and other serotypes that commonly cause ocular disease (3, 4, 7, 11) was confirmed in house using acquired strains (ATCC, Chantilly, Virginia, USA).14
RESULTS FROM NOVEMBER 22, 2011 TO OCTOBER 31, 2014, 858 OF 4883
initial employee Occupational Health visits (18%) were due to unique, eye-related complaints. The number of employees seen with eye concerns ranged from 6 to 36 per month (Figure 2). Most employees complained of red eye.
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FIGURE 1. Schema of red-eye employee triage system at the Johns Hopkins Hospital with employee totals from November 2011 through October 2014. EKC [ epidemic keratoconjunctivitis; NP [ nurse practitioner; PCR [ polymerase chain reaction. In all cases, employees are required at the end of their furlough to return to Occupational Health for clearance before return to duty.
Of the 858 employees with eye concerns, 542 (62%) underwent conjunctival swabbing and adenovirus PCR testing (Figure 1). Forty-four employees (8% of suspected adenoviral cases, or 5% of all employees with eye concerns) were positive for adenovirus by real-time PCR. Adenovirus serotype could be determined for 32 employees. Overall, 14 employees had serotypes commonly associated with EKC and/or signs and symptoms consistent with EKC. EKCassociated serotypes that were detected included type 37 (n ¼ 6), 8 (n ¼ 4), and 19 (n ¼ 1). Three of 8 employees infected with serotype 4 had signs and symptoms consistent with EKC. The 5 other employees infected with serotype 4 had less severe conjunctivitis. Other serotypes found were 3 (n ¼ 5), 56 (n ¼ 4), 1 (n ¼ 2), 7 (n ¼ 1), and 42 (n ¼ 1). Serotype could not be determined by sequencing for 12 employees. Although adenovirus DNA was detected by realtime PCR from these 12 samples, no PCR products were obtained with the less sensitive nested PCR reaction used for serotype determination. A semiquantitative analysis of cycle thresholds at which adenovirus DNA amplification was detected suggested that samples that could not be serotyped contained approximately 1000-fold less DNA than samples for which serotype was obtained. The median PCR cycle at which adenovirus DNA was detected by real-time PCR was 41 for samples that could not be serotyped, compared to 33 for samples for which a serotype was obtained. None of the 12 patients whose samples could not be serotyped had EKC. 40
More than half (469/858; 55%) of employees had conditions that were determined to be noninfectious after consultation by a Wilmer or private ophthalmologist; allergic conjunctivitis was most common. The other diagnoses included corneal or conjunctival foreign body, pinguecula, episcleritis, scleritis, corneal abrasion, contact lens overuse, iritis, dacryocystitis, and preseptal cellulitis. The remainder (389/858; 45%) had adenoviral infection confirmed by PCR (44 listed above) or were diagnosed with ‘‘viral’’ or ‘‘bacterial’’ conjunctivitis by an ophthalmologist (either at Wilmer or in the community), a primary care provider, or a doctor at an urgent care center. Conjunctival cultures were not reported for any of these employees, implying that ‘‘viral’’ or ‘‘bacterial’’ was a clinical diagnosis. The majority of employees seen by primary care providers and urgent care doctors were started on topical antibiotic therapy. To compare the prevalence of laboratory-diagnosed adenoviral conjunctivitis among healthcare employees with eye concerns with the prevalence of this condition among general ophthalmology patients as diagnosed by clinical examination and/or culture, we examined billing data from the Wilmer General Eye Service. Visits with billing diagnoses consistent with adenoviral conjunctivitis (including International Classification of Diseases, 9th revision [ICD-9] codes 372.00, 372.03, 372.71, 379.93, 077.1, 077.3, 077.4, and 077.8) were analyzed. In the 2year period prior to red-eye room closure (January 2006
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FIGURE 2. Employees seen for eye concerns, adenovirus polymerase chain reaction (PCR) tests ordered, and positive adenovirus PCR results during the first 36 months of algorithm use.
through January 2008), there were 9609 patient visits with unique diagnoses (ie, follow-up visits for the same diagnosis for the patient were excluded). An ICD-9 code consistent with adenoviral conjunctivitis was attached to 986 visits; the vast majority of diagnoses were made clinically. Therefore, the prevalence of clinically diagnosed adenoviral conjunctivitis in the General Eye Service was 986 of 9609, or 10%.
DISCUSSION THE NEW TRIAGE ALGORITHM FOR HOSPITAL EMPLOYEES
with red eye has achieved its goal to isolate and furlough employees with adenoviral conjunctivitis in a rapid manner, thus preventing spread of disease to patients and other employees. The causes of red eye in hospital employees are now recorded systematically at 1 location (rather than simple description of red eye and varying levels of evaluation at multiple clinics), and the prevalence of adenoviral infection, as well as infecting serotypes, can be monitored for epidemiologic purposes. To our knowledge, there is no other similar institution-wide triage sysVOL. 163
tem for adenoviral conjunctivitis, nor has there been any report of adenovirus serotype or prevalence in hospital employees, which, by PCR diagnosis, is lower than clinical diagnosis would indicate. This algorithm has several potential benefits. First, PCR offers state-of-the art sensitivity and specificity compared to other methods, such as culture and antigen detection. Second, the initial evaluation of healthcare workers at a single site by a select group of trained providers maximizes the likelihood of adherence to EKC prevention policies and decreases the possibility of healthcare-associated spread. Prior to this algorithm, numerous different clinicians evaluated employees, adenovirus cultures were infrequently obtained, adenoviral conjunctivitis was often clinically diagnosed, and identification of EKC-related serotypes was not performed. Moreover, many ophthalmologists are reluctant to examine cases of probable viral conjunctivitis, necessitating this algorithm. Third, given that clinical diagnosis of this disease is imperfect and that initial screening by nurse practitioners at Occupational Health is expected to yield false-positive cases, adjunctive use of PCR testing in employees with suspected adenoviral conjunctivitis facilitates judicious use of furlough for infection prevention. In the findings above, there was almost a
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10-fold difference between diagnostically confirmed and clinically suspicious cases (44 employees with serotype and disease course consistent with adenoviral conjunctivitis vs 542 with clinically suspicious findings); furlough of over 500 employees over a 3-year period would have been impractical. Determination of adenovirus prevalence and delineation of serotypes in hospital employees with red eye became important objectives once the triage algorithm was implemented. Prevalence of adenoviral conjunctivitis among hospital personnel with eye concerns (5%) was less than half that seen in General Eye Service patients (10%) in whom the infection was clinically diagnosed. Possible explanations for this difference include different prevalence of adenoviral conjunctivitis between the general public and hospital employees or the comparatively lower specificity of clinical diagnosis compared with PCR testing. Most likely some of the clinically diagnosed cases in the General Eye Service were not truly adenoviral, which is supported by findings of the current study. Retrospective molecular serotyping showed that approximately 30% of the employees with adenoviral conjunctivitis were infected with an EKC-associated strain, which raised the question of whether the algorithm should include prospective serotype determination to tailor furlough duration. For example, employees with EKCassociated serotypes could be assigned a 2-week work furlough while those with other serotypes could be furloughed for a shorter duration until resolution of clinical symptoms; clinical clearance by Occupational Health nurse practitioners would be required to return to work in either situation. The 2-week furlough commonly recommended for patients with presumed or definite adenoviral conjunctivitis may have arisen in part from a report of a large outbreak of EKC in an ophthalmology department in which adenovirus was isolated from conjunctival surfaces up to 2 weeks after the onset of clinical illness.12 In spring 2014, however, based on the low prevalence of EKC in employees suspected of having viral conjunctivitis and a suspicion that many employees with adenoviral conjunctivitis recovered well in advance of the 2-week mark, the ophthalmologist involved in developing this policy suggested that the nurse case manager call furloughed employees at the 1-week mark. Most employees with non-EKC serotypes reported not having any tearing, redness, or discomfort at that time point. Compilation of such reports after 2 months suggested that a 2-week furlough might be unnecessary for the majority of employees with adenoviral conjunctivitis. Therefore, in April 2014 the red-eye policy was further modified. In this manner, serotyping is done prospectively (with results in 2–5 days) and furlough length is tailored depending on whether serotype is typical for EKC (types 4, 8, 19, 37) and whether signs and symptoms are consistent with EKC. The nurse practitioners call employees 5–6 days after 42
presentation to Occupational Health to inquire of their symptoms. If the employee is still symptomatic, the furlough continues. If the employee is relatively asymptomatic, the nurse practitioner asks the employee to return to Occupational Health to be cleared for work; the vast majority of employees with non-EKC serotypes are able to work after a 7-day furlough. As before, in all cases, employees require clearance by Occupational Health in order to return to work. Detection of adenovirus by PCR does not imply the eye is infectious, and adenoviral conjunctivitis can span from mild disease to EKC. Though there are other infectious conjunctivitides (eg, enteroviral), which typically resolve within 5–7 days,24 adenoviral conjunctivitis is more common and potential complications (such as chronic visual symptoms from keratitis) are more severe. For these reasons, the focus of this PCR-based algorithm was adenovirus detection. Based on a preliminary analysis, the red-eye algorithm has been cost effective for our institution. This analysis was based on Johns Hopkins Hospital absorbing the cost of PCR performed on employees with clinical suspicion of adenoviral conjunctivitis (542) and the cost to the hospital of furloughing only PCR-positive employees (44) for 2 weeks vs the cost of furloughing all 542 employees, as might have been done prior to this algorithm. From serotype prevalence and record of employees’ clinical course, it appears that the 2-week furlough is excessive for most employees with adenoviral conjunctivitis. If trends continue, based on the distribution of serotypes and furlough lengths (one-third of employees with adenovirus conjunctivitis having EKC-associated serotypes requiring 2 weeks vs two-thirds with non-EKC-related serotypes requiring 1 week), the number of furlough days potentially could be reduced by another third. A more flexible policy, invoking shorter or longer furlough based on community molecular epidemiologic data of circulating adenovirus serotypes, as begun in April 2014, may be more appropriate and deserves further investigation. While PCR for adenovirus is available, there is currently no commercially available PCR test for the detection of adenovirus in conjunctival specimens. Therefore, clinical laboratories must develop their own tests for this use. Laboratory-developed tests are regulated by a federal law entitled Clinical Laboratory Improvement Act, which stipulates that laboratories can develop and offer tests clinically if they ascertain the analytical performance characteristics of the test. For molecular infectious disease tests, analytical sensitivity is defined as limit of detection, which is determined in experiments with a dilution series of concentrations, and is defined as the concentration of the panel member for which 95% of replicates are detected. Manufacturers seeking Food and Drug Administration (FDA) approval to market a test are held to the standard of a clinical trial to define the clinical indication for the test and the clinical performance characteristics relative
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to disease, defined by clinical symptoms and the results of a gold-standard diagnostic test (clinical sensitivity and clinical specificity). Such determinations are not required of laboratory-developed tests. Demonstrating clinical need for initiatives like the one described herein may motivate other centers to adopt some or all parts of the algorithm to diagnose adenoviral conjunctivitis accurately in order to limit transmission of disease. The perceived benefit from such testing also may provide commercial impetus for development of an FDA-cleared/approved PCR-based test for adenoviral conjunctivitis that can be used in hospitals, clinics, and other settings. The inability to sequester a potentially large number of individuals with possible infectious conjunctivitis in a designated room in the Department of Ophthalmology led us to develop an algorithm for rapid diagnosis of adenoviral conjunctivitis in hospital employees, who have the
potential to infect patients and other employees alike. Implementation required a multidisciplinary effort across several hospital departments and divisions. This comprehensive institutional policy has allowed for accurate detection and tracking of the prevalence of adenoviral conjunctivitis, and judicious application of furlough based on objective criteria. The relative simplicity and functional benefits of this effort suggest that it merits consideration as a practice model for hospitals and clinics seeking to prevent healthcare-associated transmission of adenoviral conjunctivitis. The addition of serotyping furthers our understanding of the prevalence of adenoviruses that cause EKC. It also provides preliminary data to support the development of tests (such as a carefully designed multiplex PCR test) that are simpler to perform but as accurate as direct Sanger sequencing to detect all adenoviruses and to distinguish those that cause EKC.
FUNDING/SUPPORT: UNRESTRICTED INSTITUTIONAL SUPPORT FROM RESEARCH TO PREVENT BLINDNESS, NEW YORK, New York. Financial disclosures: The following authors have no financial disclosures: Irene C. Kuo, Colleen Espinosa, Michael Forman, and Alexandra Valsamakis. All authors attest that they meet the current ICMJE criteria for authorship.
REFERENCES 1. Gordon JS. Clinical disease: adenovirus and other nonherpetic viral diseases. In: Smolin G, Thoft RA, eds. The Cornea: Scientific Foundations and Clinical Practice. New York: Little, Brown and Company; 1994:217–219. 2. Tabbara KF, Omar N, Hammouda E, et al. Molecular epidemiology of adenoviral keratoconjunctivitis in Saudi Arabia. Mol Vis 2010;16(10):2132–2136. 3. Hiroi S, Morikawa S, Takahashi K, Komano J, Kase T. Molecular epidemiology of human adenoviruses d associated with epidemic keratoconjunctivitis in Osaka, Japan, 2001-2010. Jpn J Infect Dis 2013;66(5):436–438. 4. Dawson CR, Hanna L, Wood TR, Despain R. Adenovirus type 8 keratoconjunctivitis in the United States. 3. Epidemiologic, clinical, and microbiologic features. Am J Ophthalmol 1970;69(3):473–480. 5. Jones BR. The clinical features of viral keratitis and a concept of their pathogenesis. Proc Roy Soc Med 1958;51(11):13–20. 6. Montessori V, Scharf S, Holland S, Werker DH, Roberts FJ, Bryce E. Epidemic keratoconjunctivitis outbreak at a tertiary referral eye care clinic. Am J Infect Control 1998;26(4): 399–405. 7. Cheung D, Bremner J, Chan JTK. Epidemic keratoconjunctivitis—do outbreaks have to be epidemic? Eye 2003;17(3): 356–363. 8. Klapper PE, Cleator GM. Adenovirus cross-infection: a continuing problem. J Hosp Infect 1995;30(Suppl):262–267. 9. Hamada N, Gotoh K, Hara K, et al. Nosocomial outbreak of epidemic keratoconjunctivitis accompanying environmental contamination with adenoviruses. J Hosp Infect 2008;68(3): 262–268. 10. Piednoir E, Bureau-Chalot F, Merle C, Gotzmanis A, Wulbout J, Bajolet O. Direct costs associated with a nosocomial outbreak of adenoviral conjunctivitis infection in a
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long-term care instititution. Am J Infect Control 2002;30(7): 407–410. Dart JK, El-Amir AN, Maddison T, et al. Identification and control of nosocomial adenovirus keratoconjunctivitis in an ophthalmic department. Br J Ophthalmol 2009;93(1): 18–20. Warren D, Nelson KE, Farrar JA, et al. A large outbreak of epidemic keratoconjunctivitis. J Infect Dis 1989;160(6): 938–943. Gottsch JD, Froggatt JW, Smith DM, et al. Prevention and control of epidemic keratoconjunctivitis in a teaching eye institute. Ophthalmic Epidemiol 1999;6(1):29–39. Kuo IC, Espinosa C, Forman M, Pehar M, Maragakis LL, Valsamakis A. Detection and prevalence of adenoviral conjunctivitis among hospital employees using real-time polymerase chain reaction as an infection prevention tool. Infect Control Hosp Epidemiol 2014;35(6):728–731. Aoki K, Kato M, Ohtsuka H, Ishii K, Nakazono N, Sawada H. Clinical and aetiological study of adenoviral conjunctivitis, with special reference to adenovirus type 4 and 19 infections. Br J Ophthalmol 1982;66(12):776–780. Aoki K, Kawana R, Matsumoto I, Wadell G, de Jong JC. Viral conjunctivitis with special reference to adenovirus type 37 and enterovirus 70 infection. Jpn J Ophthalmol 1986;30(2): 158–164. Aoki K, Tagawa Y. A twenty-one year surveillance of adenoviral conjunctivitis in Sapporo, Japan. Int Ophthalmol Clin 2002;42(1):49–54. de Jong JC, Wigand R, Wadell G, et al. Adenovirus 37: identification and characterization of a medically important new adenovirus type of subgroup D. J Med Virol 1981;7(2): 105–118. Desmyter J, De Jong JC, Slaterus KW, Verlaeckt H. Keratoconjunctivitis caused by adenovirus type 19 [letter]. Br Med J 1974;4(5941):406.
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20. Jawetz E, Kimura S, Nicholas AN, Thygeson P, Hanna P. New type of APC virus from epidemic keratoconjunctivitis. Science 1955;122(3181):1190–1191. 21. World WSM, Horowitz MS. Adenoviridae. In: Knipe DM, Howley PM, Griffin DE, et al., eds. Fields Virology. Philadelphia: Lippincott Williams & Wilkins; 2007:2395–2396. 22. Heim A, Ebnet C, Harste G, Pring-Akerblom P. Rapid and quantitative detection of human adenovirus DNA by realtime PCR. J Med Virol 2003;70(2):228–239.
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23. Lu X, Erdman DD. Molecular typing of human adenoviruses by PCR and sequencing of a partial region of the hexon gene. Arch Virol 2006;151(8): 1587–1602. 24. Gordon JS. Clinical disease: adenovirus and other nonherpetic viral diseases. In: Smolin G, Thoft RA, eds. The Cornea: Scientific Foundations and Clinical Practice. New York: Little, Brown and Company; 1994:222.
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To devise and implement a practice algorithm that would enable rapid detection and appropriate furlough of hospital employees with adenoviral conjunctivitis in order to prevent healthcare-associated epidemic keratoconjunctivitis. DESIGN: Evaluation of an ongoing quality assurance/ improvement initiative. METHODS: Employees of Johns Hopkins Hospital with signs and symptoms of adenoviral conjunctivitis underwent evaluation by nurse practitioners in Occupational Health and rapid diagnostic testing by real-time polymerase chain reaction (PCR). Sequencing was used to determine serotype when adenovirus was detected. Signs, symptoms, diagnosis, and disposition of employees with eye complaints as well as PCR and serotype results were recorded. RESULTS: Over a 36-month period approximately 18% of initial employee visits were due to unique, eyerelated complaints. Viral conjunctivitis was suspected in 542 of 858 employees with eye complaints (62%); adenovirus was detected by PCR in 44 of 542 suspected viral conjunctivitis cases (8%) or 44 of 858 employees with any eye concern (5%). Fourteen of the 44 employees had adenoviral serotypes and clinical presentation consistent with epidemic keratoconjunctivitis (type 37 [n [ 6], 8 [n [ 4], 4 [n [ 3], 19 [n [ 1]). Other serotypes found in individuals with less severe conjunctivitis were 3 (n [ 5), 4 (n [ 5), 56 (n [ 4), 1 (n [ 2), 42 (n [ 1), and 7 (n [ 1). No healthcareassociated adenoviral conjunctivitis outbreaks occurred after algorithm implementation, and fewer employees required furlough than had clinical diagnosis alone been used. CONCLUSIONS: The algorithm is an effective infection prevention tool that minimizes productivity loss compared to clinical diagnosis and allows for determination of prevalence and serotype characterization of adeno-
Supplemental Material available at AJO.com. Accepted for publication Dec 4, 2015. From the Wilmer Eye Institute, Department of Ophthalmology, The Johns Hopkins University School of Medicine (I.C.K.); and the Division of Occupational and Environmental Medicine (C.E.) and Division of Medical Microbiology, Department of Pathology (M.F., A.V.), The Johns Hopkins Hospital, Baltimore, Maryland. Inquiries to Irene C. Kuo, Wilmer Eye Institute, 4924 Campbell Blvd #100, Baltimore, MD 21236; e-mail: [email protected]
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viral conjunctivitis in hospital employees. (Am J Ophthalmol 2016;163:38–44. Ó 2016 by Elsevier Inc. All rights reserved.)
A
DENOVIRAL EYE INFECTION IS A PUBLIC HEALTH
concern, with manifestations ranging from selflimited conjunctivitis to prolonged ocular morbidity in the case of epidemic keratoconjunctivitis (EKC). Some adenoviral infections, however, may not be easily distinguishable from EKC at presentation; the 3 other clinical scenarios are nonspecific follicular conjunctivitis, pharyngeal conjunctival fever, and acute hemorrhagic conjunctivitis. EKC is most commonly caused by serotypes 8, 19, and 371; less typical serotypes associated with EKC are 4,2 53, and 54.3 EKC is more clinically obvious and induces more morbidity than the other adenoviral eye conditions and is associated with a longer disease course and significant injection, chemosis, and keratitis that can impair vision.4,5 Outbreaks in hospitals and eye clinics result in substantial morbidity and lost productivity.6–12 In response to healthcare-associated EKC outbreaks,6–12 one of which resulted in the temporary closure of a large eye institute,12 a ‘‘red-eye room,’’ where persons with potentially infectious conjunctivitis could be triaged and isolated, was established in 1990 in the Wilmer Eye Institute Emergency Room (ER), Department of Ophthalmology, at the Johns Hopkins Hospital (JHH).13 This arrangement was part of an infection prevention program consisting of ophthalmic instrument decontamination, hand hygiene, use of single-dose eye drops, and employee furloughs.14 When institutional changes led to the permanent closure of the Wilmer ER and the red-eye room at the end of January 2008, a multidisciplinary team composed of a cornea specialist and stakeholders in infection prevention, employee health, and the clinical virology/molecular infectious disease clinical diagnostic laboratory was convened in order to devise and implement a new practice algorithm for preventing healthcareassociated transmission of adenoviral eye disease. Twentymonth pilot data have been published.14 Here we report 36-month data on adenovirus detection rates and the results of adding serotype determination to this infection prevention practice algorithm as applied to healthcare workers with red eye.
ELSEVIER INC. ALL
RIGHTS RESERVED.
0002-9394/$36.00 http://dx.doi.org/10.1016/j.ajo.2015.12.007
METHODS THE INSTITUTIONAL REVIEW BOARDS OF JOHNS HOPKINS
Medicine ruled that publishing of an evaluation of this quality improvement initiative did not require approval as it ‘‘does not involve human subjects research under the Department of Health and Human Services or Food and Drug Administration regulations.’’ The new red-eye employee practice algorithm, which is in effect at all times, is shown in Figure 1. It consists of initial evaluation by nurse practitioners in the Occupational Health clinic and rapid diagnostic testing by realtime polymerase chain reaction (PCR) in individuals with signs and symptoms consistent with adenoviral conjunctivitis. The Occupational Health clinic sees employees with health concerns that arise during work hours and may impinge on their ability to work. In order to limit the possibility of transmission within the clinic, employees seeking red-eye evaluation are required to call ahead to make an appointment. A corneal specialist taught nurse practitioners in the Occupational Health clinic to recognize signs and symptoms of probable viral conjunctivitis (vs conditions like suspected corneal abrasion or subconjunctival hemorrhage) and how to collect swab specimens of the inferior conjunctival fornix.14 The nurse practitioners were instructed to swab only when viral conjunctivitis was suspected. Swabs (polyester, Dacron, or rayon with plastic or aluminum shafts) were placed in M4 medium and sent at room temperature for PCR testing performed daily at the JHH Clinical Virology/Molecular Infectious Disease Diagnostic Laboratory. Screening criteria included duration of symptoms, presence of viral prodrome, discharge or tearing, and unilateral onset. Employees with suspected viral conjunctivitis were evaluated, swabbed, and discharged home within 30 minutes of intake. Nurse practitioners notified employees of PCR results and furlough status by 8 PM if specimens were received in the laboratory by 3 PM. If adenovirus was detected by PCR, a 2-week furlough was invoked. Direct sequencing of specimens found to contain adenovirus DNA was performed retrospectively for epidemiologic purposes—to determine the proportion of employees infected with EKCassociated adenoviral serotypes (most typically types 8, 19, and 37).15–21 Toward the end of the furlough, the nurse case manager in the Occupational Health clinic contacted employees with adenoviral conjunctivitis by phone to assess symptoms and to schedule a follow-up examination at Occupational Health that was required before return to duty. Furlough was continued if symptoms and signs of conjunctivitis persisted, given probable infectious potential. Employees were sent to the Department of Ophthalmology for consultation for conditions the nurse practitioners deemed an emergency; symptoms including but not limited to persis-
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tent redness, tearing, pain, and blurred vision; or conditions in which the nurse practitioners were unsure of diagnosis. ADENOVIRAL DETECTION AND SEROTYPE DETERMINA14 TION: As described in the pilot study, PCR for adeno-
virus in conjunctival specimens of employees was developed and validated in the Johns Hopkins Hospital molecular microbiology diagnostic laboratory. ‘‘Total nucleic acid was isolated from conjunctival specimens (processed volume, 400 microliters) using automated instrumentation (BioRobot M48, using Virus Mini Protocol, version 1.1 software and MagAttract Virus Mini M48 reagents [Qiagen, Germantown, MD];’’14 elution volume, 125 mL). Adenovirus DNA was detected by real-time PCR (primers: 59 -GCC ACG GTG GGG TTT CTA AAC TT-39 , 59 -GCC CCA GTG GTC TTA CAT GCA CAT C-39 ; fluorogenic probe FAM 59 -TGC ACC AGA CCC GGG CTC AGG TAC TCC GA-39 TAMRA)22 using 7500 Real Time PCR instruments (Life Technologies, Carlsbad, California, USA). The analytical sensitivity (95% detection rate or limit of detection) is 300 copies/mL, and the assay detects at least 16 adenovirus serotypes, including strains from 6 of 7 adenovirus serogroups (A-F). When adenoviruses were detected, serotype was determined by nested PCR of the hexon gene hypervariable regions 1–623 using previously extracted total nucleic acid (outer primers: AdhexF1 (19135-19160) 59 -TIC TTT GAC ATI CGI GGI GTI CTI GA-39 / AdhexR1 (20009-20030) 59 -CTG TCI ACI GCC TGR TTC CAC A-39 ; inner primers: AdhexF2 (19165-19187) 59 -GGY CCY AGY TTY AAR CCC TAY TC-39 / AdhexR2 (19960-19985) 59 -GGT TCT GTC ICC CAG AGA RTC IAG CA-39 ) followed by bidirectional Sanger sequencing using AdhexF2/AdhexR2 as sequencing primers in reactions containing BigDye Terminator v.3.1 (Life Technologies). Sequencing was performed on either a 3100 or a 3500 Genetic Analyzer (Life Technologies). These reagents correctly identified 50 prototype strains; serotypes 15 and 29 have identical sequences in the queried region, cannot be distinguished,23 and therefore are reported as 15/29. The ability to identify serotypes associated with ocular disease (8, 19, 37) and other serotypes that commonly cause ocular disease (3, 4, 7, 11) was confirmed in house using acquired strains (ATCC, Chantilly, Virginia, USA).14
RESULTS FROM NOVEMBER 22, 2011 TO OCTOBER 31, 2014, 858 OF 4883
initial employee Occupational Health visits (18%) were due to unique, eye-related complaints. The number of employees seen with eye concerns ranged from 6 to 36 per month (Figure 2). Most employees complained of red eye.
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FIGURE 1. Schema of red-eye employee triage system at the Johns Hopkins Hospital with employee totals from November 2011 through October 2014. EKC [ epidemic keratoconjunctivitis; NP [ nurse practitioner; PCR [ polymerase chain reaction. In all cases, employees are required at the end of their furlough to return to Occupational Health for clearance before return to duty.
Of the 858 employees with eye concerns, 542 (62%) underwent conjunctival swabbing and adenovirus PCR testing (Figure 1). Forty-four employees (8% of suspected adenoviral cases, or 5% of all employees with eye concerns) were positive for adenovirus by real-time PCR. Adenovirus serotype could be determined for 32 employees. Overall, 14 employees had serotypes commonly associated with EKC and/or signs and symptoms consistent with EKC. EKCassociated serotypes that were detected included type 37 (n ¼ 6), 8 (n ¼ 4), and 19 (n ¼ 1). Three of 8 employees infected with serotype 4 had signs and symptoms consistent with EKC. The 5 other employees infected with serotype 4 had less severe conjunctivitis. Other serotypes found were 3 (n ¼ 5), 56 (n ¼ 4), 1 (n ¼ 2), 7 (n ¼ 1), and 42 (n ¼ 1). Serotype could not be determined by sequencing for 12 employees. Although adenovirus DNA was detected by realtime PCR from these 12 samples, no PCR products were obtained with the less sensitive nested PCR reaction used for serotype determination. A semiquantitative analysis of cycle thresholds at which adenovirus DNA amplification was detected suggested that samples that could not be serotyped contained approximately 1000-fold less DNA than samples for which serotype was obtained. The median PCR cycle at which adenovirus DNA was detected by real-time PCR was 41 for samples that could not be serotyped, compared to 33 for samples for which a serotype was obtained. None of the 12 patients whose samples could not be serotyped had EKC. 40
More than half (469/858; 55%) of employees had conditions that were determined to be noninfectious after consultation by a Wilmer or private ophthalmologist; allergic conjunctivitis was most common. The other diagnoses included corneal or conjunctival foreign body, pinguecula, episcleritis, scleritis, corneal abrasion, contact lens overuse, iritis, dacryocystitis, and preseptal cellulitis. The remainder (389/858; 45%) had adenoviral infection confirmed by PCR (44 listed above) or were diagnosed with ‘‘viral’’ or ‘‘bacterial’’ conjunctivitis by an ophthalmologist (either at Wilmer or in the community), a primary care provider, or a doctor at an urgent care center. Conjunctival cultures were not reported for any of these employees, implying that ‘‘viral’’ or ‘‘bacterial’’ was a clinical diagnosis. The majority of employees seen by primary care providers and urgent care doctors were started on topical antibiotic therapy. To compare the prevalence of laboratory-diagnosed adenoviral conjunctivitis among healthcare employees with eye concerns with the prevalence of this condition among general ophthalmology patients as diagnosed by clinical examination and/or culture, we examined billing data from the Wilmer General Eye Service. Visits with billing diagnoses consistent with adenoviral conjunctivitis (including International Classification of Diseases, 9th revision [ICD-9] codes 372.00, 372.03, 372.71, 379.93, 077.1, 077.3, 077.4, and 077.8) were analyzed. In the 2year period prior to red-eye room closure (January 2006
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FIGURE 2. Employees seen for eye concerns, adenovirus polymerase chain reaction (PCR) tests ordered, and positive adenovirus PCR results during the first 36 months of algorithm use.
through January 2008), there were 9609 patient visits with unique diagnoses (ie, follow-up visits for the same diagnosis for the patient were excluded). An ICD-9 code consistent with adenoviral conjunctivitis was attached to 986 visits; the vast majority of diagnoses were made clinically. Therefore, the prevalence of clinically diagnosed adenoviral conjunctivitis in the General Eye Service was 986 of 9609, or 10%.
DISCUSSION THE NEW TRIAGE ALGORITHM FOR HOSPITAL EMPLOYEES
with red eye has achieved its goal to isolate and furlough employees with adenoviral conjunctivitis in a rapid manner, thus preventing spread of disease to patients and other employees. The causes of red eye in hospital employees are now recorded systematically at 1 location (rather than simple description of red eye and varying levels of evaluation at multiple clinics), and the prevalence of adenoviral infection, as well as infecting serotypes, can be monitored for epidemiologic purposes. To our knowledge, there is no other similar institution-wide triage sysVOL. 163
tem for adenoviral conjunctivitis, nor has there been any report of adenovirus serotype or prevalence in hospital employees, which, by PCR diagnosis, is lower than clinical diagnosis would indicate. This algorithm has several potential benefits. First, PCR offers state-of-the art sensitivity and specificity compared to other methods, such as culture and antigen detection. Second, the initial evaluation of healthcare workers at a single site by a select group of trained providers maximizes the likelihood of adherence to EKC prevention policies and decreases the possibility of healthcare-associated spread. Prior to this algorithm, numerous different clinicians evaluated employees, adenovirus cultures were infrequently obtained, adenoviral conjunctivitis was often clinically diagnosed, and identification of EKC-related serotypes was not performed. Moreover, many ophthalmologists are reluctant to examine cases of probable viral conjunctivitis, necessitating this algorithm. Third, given that clinical diagnosis of this disease is imperfect and that initial screening by nurse practitioners at Occupational Health is expected to yield false-positive cases, adjunctive use of PCR testing in employees with suspected adenoviral conjunctivitis facilitates judicious use of furlough for infection prevention. In the findings above, there was almost a
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10-fold difference between diagnostically confirmed and clinically suspicious cases (44 employees with serotype and disease course consistent with adenoviral conjunctivitis vs 542 with clinically suspicious findings); furlough of over 500 employees over a 3-year period would have been impractical. Determination of adenovirus prevalence and delineation of serotypes in hospital employees with red eye became important objectives once the triage algorithm was implemented. Prevalence of adenoviral conjunctivitis among hospital personnel with eye concerns (5%) was less than half that seen in General Eye Service patients (10%) in whom the infection was clinically diagnosed. Possible explanations for this difference include different prevalence of adenoviral conjunctivitis between the general public and hospital employees or the comparatively lower specificity of clinical diagnosis compared with PCR testing. Most likely some of the clinically diagnosed cases in the General Eye Service were not truly adenoviral, which is supported by findings of the current study. Retrospective molecular serotyping showed that approximately 30% of the employees with adenoviral conjunctivitis were infected with an EKC-associated strain, which raised the question of whether the algorithm should include prospective serotype determination to tailor furlough duration. For example, employees with EKCassociated serotypes could be assigned a 2-week work furlough while those with other serotypes could be furloughed for a shorter duration until resolution of clinical symptoms; clinical clearance by Occupational Health nurse practitioners would be required to return to work in either situation. The 2-week furlough commonly recommended for patients with presumed or definite adenoviral conjunctivitis may have arisen in part from a report of a large outbreak of EKC in an ophthalmology department in which adenovirus was isolated from conjunctival surfaces up to 2 weeks after the onset of clinical illness.12 In spring 2014, however, based on the low prevalence of EKC in employees suspected of having viral conjunctivitis and a suspicion that many employees with adenoviral conjunctivitis recovered well in advance of the 2-week mark, the ophthalmologist involved in developing this policy suggested that the nurse case manager call furloughed employees at the 1-week mark. Most employees with non-EKC serotypes reported not having any tearing, redness, or discomfort at that time point. Compilation of such reports after 2 months suggested that a 2-week furlough might be unnecessary for the majority of employees with adenoviral conjunctivitis. Therefore, in April 2014 the red-eye policy was further modified. In this manner, serotyping is done prospectively (with results in 2–5 days) and furlough length is tailored depending on whether serotype is typical for EKC (types 4, 8, 19, 37) and whether signs and symptoms are consistent with EKC. The nurse practitioners call employees 5–6 days after 42
presentation to Occupational Health to inquire of their symptoms. If the employee is still symptomatic, the furlough continues. If the employee is relatively asymptomatic, the nurse practitioner asks the employee to return to Occupational Health to be cleared for work; the vast majority of employees with non-EKC serotypes are able to work after a 7-day furlough. As before, in all cases, employees require clearance by Occupational Health in order to return to work. Detection of adenovirus by PCR does not imply the eye is infectious, and adenoviral conjunctivitis can span from mild disease to EKC. Though there are other infectious conjunctivitides (eg, enteroviral), which typically resolve within 5–7 days,24 adenoviral conjunctivitis is more common and potential complications (such as chronic visual symptoms from keratitis) are more severe. For these reasons, the focus of this PCR-based algorithm was adenovirus detection. Based on a preliminary analysis, the red-eye algorithm has been cost effective for our institution. This analysis was based on Johns Hopkins Hospital absorbing the cost of PCR performed on employees with clinical suspicion of adenoviral conjunctivitis (542) and the cost to the hospital of furloughing only PCR-positive employees (44) for 2 weeks vs the cost of furloughing all 542 employees, as might have been done prior to this algorithm. From serotype prevalence and record of employees’ clinical course, it appears that the 2-week furlough is excessive for most employees with adenoviral conjunctivitis. If trends continue, based on the distribution of serotypes and furlough lengths (one-third of employees with adenovirus conjunctivitis having EKC-associated serotypes requiring 2 weeks vs two-thirds with non-EKC-related serotypes requiring 1 week), the number of furlough days potentially could be reduced by another third. A more flexible policy, invoking shorter or longer furlough based on community molecular epidemiologic data of circulating adenovirus serotypes, as begun in April 2014, may be more appropriate and deserves further investigation. While PCR for adenovirus is available, there is currently no commercially available PCR test for the detection of adenovirus in conjunctival specimens. Therefore, clinical laboratories must develop their own tests for this use. Laboratory-developed tests are regulated by a federal law entitled Clinical Laboratory Improvement Act, which stipulates that laboratories can develop and offer tests clinically if they ascertain the analytical performance characteristics of the test. For molecular infectious disease tests, analytical sensitivity is defined as limit of detection, which is determined in experiments with a dilution series of concentrations, and is defined as the concentration of the panel member for which 95% of replicates are detected. Manufacturers seeking Food and Drug Administration (FDA) approval to market a test are held to the standard of a clinical trial to define the clinical indication for the test and the clinical performance characteristics relative
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to disease, defined by clinical symptoms and the results of a gold-standard diagnostic test (clinical sensitivity and clinical specificity). Such determinations are not required of laboratory-developed tests. Demonstrating clinical need for initiatives like the one described herein may motivate other centers to adopt some or all parts of the algorithm to diagnose adenoviral conjunctivitis accurately in order to limit transmission of disease. The perceived benefit from such testing also may provide commercial impetus for development of an FDA-cleared/approved PCR-based test for adenoviral conjunctivitis that can be used in hospitals, clinics, and other settings. The inability to sequester a potentially large number of individuals with possible infectious conjunctivitis in a designated room in the Department of Ophthalmology led us to develop an algorithm for rapid diagnosis of adenoviral conjunctivitis in hospital employees, who have the
potential to infect patients and other employees alike. Implementation required a multidisciplinary effort across several hospital departments and divisions. This comprehensive institutional policy has allowed for accurate detection and tracking of the prevalence of adenoviral conjunctivitis, and judicious application of furlough based on objective criteria. The relative simplicity and functional benefits of this effort suggest that it merits consideration as a practice model for hospitals and clinics seeking to prevent healthcare-associated transmission of adenoviral conjunctivitis. The addition of serotyping furthers our understanding of the prevalence of adenoviruses that cause EKC. It also provides preliminary data to support the development of tests (such as a carefully designed multiplex PCR test) that are simpler to perform but as accurate as direct Sanger sequencing to detect all adenoviruses and to distinguish those that cause EKC.
FUNDING/SUPPORT: UNRESTRICTED INSTITUTIONAL SUPPORT FROM RESEARCH TO PREVENT BLINDNESS, NEW YORK, New York. Financial disclosures: The following authors have no financial disclosures: Irene C. Kuo, Colleen Espinosa, Michael Forman, and Alexandra Valsamakis. All authors attest that they meet the current ICMJE criteria for authorship.
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