Changing patterns in leptospirosis: a three-decade study in Brazil

Accepted Manuscript Title: CHANGING PATTERNS IN LEPTOSPIROSIS: A THREE-DECADE STUDY IN BRAZIL Authors: Elizabeth De Francesco Daher, Gabriela Studart Galdino de Carvalho, Douglas de Sousa Soares, Matheus Henrique Mendes, S´ergio Luiz Arruda Parente Filho, Hermano Alexandre Lima Rocha, Geraldo Bezerra da Silva Junior PII: DOI: Reference:

S1201-9712(17)30135-2 http://dx.doi.org/doi:10.1016/j.ijid.2017.04.023 IJID 2938

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International Journal of Infectious Diseases

Received date: Revised date: Accepted date:

7-3-2017 25-4-2017 28-4-2017

Please cite this article as: De Francesco Daher Elizabeth, de Carvalho Gabriela Studart Galdino, de Sousa Soares Douglas, Mendes Matheus Henrique, Parente Filho S´ergio Luiz Arruda, Rocha Hermano Alexandre Lima, da Silva Junior Geraldo Bezerra.CHANGING PATTERNS IN LEPTOSPIROSIS: A THREEDECADE STUDY IN BRAZIL.International Journal of Infectious Diseases http://dx.doi.org/10.1016/j.ijid.2017.04.023 This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.

CHANGING PATTERNS IN LEPTOSPIROSIS: A THREE-DECADE STUDY IN BRAZIL

Elizabeth De Francesco Daher1, Gabriela Studart Galdino de Carvalho1, Douglas de Sousa Soares1, Matheus Henrique Mendes1, Sérgio Luiz Arruda Parente Filho1, Hermano Alexandre Lima Rocha2, Geraldo Bezerra da Silva Junior3.

1

Department of Internal Medicine, School of Medicine, Walter Cantídio University

Hospital, Federal University of Ceará. Fortaleza, Ceará, Brazil. 2

Department of Community Health, School of Medicine, Federal University of Ceará.

Fortaleza, Ceará, Brazil. 3

School of Medicine, Public Health Graduate Program, Health Sciences Center,

University of Fortaleza. Fortaleza, Ceará, Brazil.

Running Title: Changing Patterns in Leptospirosis

Address for correspondence: Elizabeth De Francesco Daher. Rua Vicente Linhares, 1198. Fortaleza, CE, Brasil – CEP: 60270-135. Phone / Fax: (+55 85) 3224-9725 / (+55 85) 3261-3777. E-mail: [email protected], [email protected]

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ABSTRACT Background: This study was conducted to investigate changes in leptospirosis clinical pattern over time, analyzing its clinical and laboratory presentation in a metropolitan city of Brazil. Method: This is a retrospective study including all patients with leptospirosis admitted to tertiary care hospitals in Fortaleza, Northeast of Brazil, between 1985 and 2015. Patients were divided into three groups according to the year of hospital admission: group I (1985–1995), group II (1996–2005) and group III (2006-2015). Demographic, clinical and laboratory data of the groups were compared. Results: A total of 507 patients were included, aged 37.3±15.9 years old, and 82.4% were males. The mean time between symptom onset and admission was 7±4 days. There was a linear decrease in the levels of serum urea (190.1 ± 92.7, 135 ± 79.5 and 95.6 ± 73.3mg/dL, p < 0.0001) and creatinine (5.8 ± 2.9, 3.8 ± 2.6 and 3.0 ± 2.5mg/dL, p < 0.0001), while levels of hemoglobin (10.31 ±1.9, 10.8 ± 2.0 and 11.5 ± 2.1g/dL, p < 0.0001) and platelets (57,900 ±52,650, 80,130 ± 68,836 and 107,101 ± 99,699/mm³, p < 0.0001) increased in each decade. There was a tendency for a linear decrease in mortality (22%, 14% and 11.6%, p =0.060). Conclusion: Leptospirosis showed significant changes over time in our region. The main changes point to a decrease in disease severity and complications, such as AKI. Mortality has decreased, being close to 11%.

Keywords: Leptospirosis; Changing Patterns; Laboratory findings; Acute kidney injury; Mortality.

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NON-TECHNICAL SUMMARY Leptospirosis is a bacterial disease transmitted by rats‟ urine, which is very common in tropical countries. We have compared the characteristics of patients with leptospirosis over a period of three decades in a large city in Brazil. There is evidence that the disease has become milder, including milder forms of renal failure, one of the most severe disease complications. We have also found a decrease in mortality. These findings can be due to more frequent and earlier identification of the disease by clinicians and, consequently, better health care provision.

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INTRODUCTION Leptospirosis remains the most important zoonosis worldwide, with higher frequency in low-income tropical countries1,2,3. It has traditionally been associated to rural areas and occupational risk, including abattoir and sewage workers, military staff and individuals involved in water sports or recreation. However, its epidemiological pattern has changed over the last decades, markedly moving to urban areas, especially during natural disasters4. This disease is endemic in Brazil, with outbreaks during the rainy season, mostly due to precarious living conditions (slums), lack of basic sanitation, presence of vectors and frequent exposures to contaminated environment during seasonal heavy rainfall and floodings4,5,6. Additionally, leptospirosis has been recognized as an important cause of undifferentiated fever, and it is usually misdiagnosed as malaria, dengue, and other causes of acute febrile illness, including the recently emerging viral diseases, such as Zika and Chikungunya6,7. Its clinical presentation may vary from a mild non-specific influenza-like infection to a severe disease with life-threatening complications, such as acute kidney injury (AKI), jaundice, pulmonary hemorrhage (Weil‟s disease), myocarditis and liver failure8,9. Unfortunately, mortality from severe leptospirosis remains unacceptably high, ranging from 5 to 20%, even when optimal treatment is provided10. Due to the lack of an adequate diagnostic test, underreporting of cases and deaths are still common, leading to morbidity and mortality underestimation6. On the other hand, some studies have shown that leptospirosis clinical pattern has been changing. An increase in the severe forms of the disease has been reported, as well as an epidemiologic spread, but mortality has decreased in the last decades, mainly due to treatment improvement and

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medical educational programs9,11,12, whereas AKI remains one of the most severe complications associated with increased mortality13. Therefore, the aim of this study is to investigate changes in leptospirosis clinical patterns over time, analyzing its clinical and laboratory presentation in a metropolitan city of Brazil.

METHODS Study population The study included all patients with a confirmed diagnosis of leptospirosis consecutively admitted to the São José Infectious Diseases Hospital, Walter Cantídio University Hospital and Fortaleza General Hospital, in Fortaleza, Northeast of Brazil, from January 1985 to December 2015. Study Design This is a retrospective cross-sectional three-decade study. Data were collected from medical records of leptospirosis patients admitted to the above mentioned tertiary care hospitals, which are the three reference hospitals in our region. Patients were divided into three groups according to hospital admission period: group I (1985–1995), group II (1996–2005) and group III (2006-2015). A comparison of demographic, clinical and laboratory data between these groups was carried out to investigate differences over this three-decade period. Case definition Leptospirosis cases were defined as the presence of positive serology at the microscopic

agglutination

test

(MAT)

higher

than

1:800,

associated

with

epidemiological and clinical history compatible with leptospirosis. Assessed parameters

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Demographic characteristics such as age, gender, time between symptom onset and hospital admission, as well as length of hospital stay were recorded. The clinical investigation included a record of all clinical signs and symptoms presented by each patient at hospital admission and during hospital stay, vital signs (systolic and diastolic blood pressures, heart rate and respiratory rate), AKI development and need for dialysis. Laboratory data on hospital admission included an assessment of serum urea, creatinine, sodium, potassium, direct bilirubin, indirect bilirubin, aspartate aminotransferase (AST), alanine aminotransferase (ALT), lactate dehydrogenase (LDH), creatine phosphokinase (CPK), hemoglobin, hematocrit, white blood cell (WBC) count, platelet count and arterial blood gas analysis. Definitions Acute kidney injury (AKI) was defined according to the “Kidney Disease Improving Global Outcomes” (KDIGO) criteria, which is currently the most accepted definition and classification for AKI14. Thrombocytopenia was defined as a platelet count lower than 150,000/mm3, anemia as hemoglobin <12g/dL and leukocytosis >12,000/mm3. Hypoalbuminemia was considered as serum albumin <3.5g/dL. The occurrence of metabolic acidosis was considered with pH <7.35 and serum bicarbonate <20mEq/L, and severe metabolic acidosis with pH<7.10. Tachypnea was defined as a respiratory rate higher than 25 breaths per minute. Oliguria was defined as urine output <400 mL/day after 24 hours of effective hydration. Hypotension was defined as mean arterial blood pressure (MAP) <60mmHg and therapy with vasoactive drugs was initiated when MAP remained lower than 60mmHg despite the use of parenteral fluids. Hypertension was defined as systolic pressure ≥140mmHg and/or diastolic pressure ≥90mmHg. Regarding dialysis therapy, hemodialysis was the method of choice instead of peritoneal dialysis, and it was intended to be initiated early after intensive care unit

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admission (<24h after AKI diagnosis) and performed daily (until significant renal function improvement). Statistical analysis The results are shown in tables, mean ± standard deviation (SD). All data were analyzed with the program SPSS, version 20.0 (IBM, USA). Kolmogorov-Smirnov test was used for numeric variables, to assess variable distribution. Analysis of variance (ANOVA) was used for comparison of data between the three studied groups. Significance level was set at 5% (p<0.05). Ethics The study protocol was approved by the Ethics Committee of São José Infectious Diseases Hospital, Walter Cantídio University Hospital and Fortaleza General Hospital, Fortaleza, Ceará, Brazil. Patients‟ identification was preserved since all data were anonymized.

RESULTS A total of 507 patients were included, aged 37.3±15.9 years old, and 82.4% were males. There were 86 patients in group I, 187 in group II and 234 in group III. There was a male gender prevalence in all groups (76.7%, 80.7% and 85.9%, respectively), and patients in group I were older (43.2±17.8 vs. 34.4±13.7 vs. 37.3±16.2 years, p < 0.0001). The mean time between symptom onset and hospitalization was nearly seven days in all groups, as shown in Table 1. The analysis of clinical manifestations showed a progressive decrease in the frequency of arrhythmias (20% vs. 11.1% vs. 0.06% respectively, p < 0.0001), chills (67.1% vs. 56.3% vs. 25.3%, p < 0.0001), dehydration (60% vs. 57.4% vs. 18.2%, p <0.0001), mental confusion (21.2% vs. 9.5% vs. 0%, p < 0.0001), jaundice (98.8% vs.

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84.9% vs. 56%, p <0.0001) and secondary infections (11.8 % vs. 7.7% vs. 4.0%, p =0.04). Diastolic blood pressure levels increased linearly (66.5±16.1 vs. 67.4±14.2 vs. 72.3±15.4 mmHg, p < 0.002). It is important to emphasize that initial lung manifestations, which had decreased significantly in the last decade, became more prevalent in the second decade as shown in Table 2. Laboratory data on hospital admission showed a linear reduction in the levels of serum urea (190±92.7 vs. 135±79.5 vs. 95.6±73.3 mg/dL, p < 0.0001) and creatinine (5.8±2.9 vs. 3.8±2.6 vs. 3.0±2.5 mg/dL, p < 0.0001), suggesting the occurrence of milder AKI in the last decade. The levels of direct bilirubin showed a consecutive reduction (15.1±10.1 vs. 11.7±8.4 vs. 5.5±6.3 mg/dL, p < 0.0001), while hemoglobin (10.3±1.9 vs. 10.8±2.0 vs. 11.5±2.1 g/dL, p < 0.0001) and platelet levels (57.9±52.6 vs. 80.1±68.8 vs. 107.1±99.7 10³/mm3, p < 0.0001) were higher in each decade, as shown in Table 3. The percentage of patients with severe AKI (KDIGO stage 3) consecutively decreased (96.3% vs. 70.1% vs. 57.4%, p <0.0001) as shown in Figure 1. Consequently, the need for dialysis also decreased (75.6%, 29.5% and 31.6%, p <0.0001). The use of antibiotics progressively increased (43.8%, 93.8% and 94.5%, p <0.0001), while the use of vasoconstrictors was significantly higher in the second and third decades (4.0% vs. 31.0% vs. 16.1%, p = 0.026), as shown in Table 4. Mortality also showed a linear reduction trend (22% vs. 14% vs. 11.6%, p = 0.060), as illustrated in Figure 2.

DISCUSSION This is the first study in the literature to assess data from leptospirosis patients during a three-decade period. We evaluated differences in clinical and laboratory patterns during a three-decade period, as well treatment evolution. The study period

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encompasses the time of the recording of the first cases in our region until recent years, and important changes were observed throughout these decades, including a decrease in AKI severity and mortality rates. Leptospirosis is a serious public health problem and a neglected disease, with higher prevalence in tropical areas, including Brazil8,15. McBride et al.16 recognized that advances were made in the understanding of leptospirosis pathogenesis, and effects of educational programs in endemic areas had an important impact on mortality decrease 9. There has been a clear improvement in the disease diagnosis, mainly due to physicians‟ awareness of the differential diagnosis of febrile illnesses in tropical countries, as well as more experience with febrile diseases affecting returning travelers16,17,18 in developed countries. Consistent with previous studies, most patients in the present study were males. Male gender has been extensively associated to leptospirosis infection risk, due to its connection with occupations traditionally attributed to men, such as abattoir and sewage workers, as well military staff. Consequently, males are usually more exposed to Leptospira spirochetes4,19. Furthermore, patients diagnosed in the last two decades of our study were significantly younger than those from the first decade. This fact may have strongly influenced the reduction in mortality and presence of less severe forms of the disease in recent years, since older patients usually have more comorbidities and a higher risk of death. Older age and the presence of comorbidities have been extensively associated to death in leptospirosis patients5,12,20. Unlike what has been previously stated, the clinical presentation of our leptospirosis patients on admission seems to have become milder over the last decade. We noticed a progressive decrease in some life-threatening manifestations, such as arrhythmias, chills, dehydration, mental confusion, jaundice, and secondary infections,

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suggesting a decrease in severe leptospirosis, mostly in the last decade. We have also observed that time between symptom onset and hospital admission has remained nearly the same, while hospital stay has decreased. This probably reflects a milder form of disease, which may be attributed to better sanitary conditions in Brazil and early diagnosis. Poor sanitation has been strongly associated with leptospirosis development in many countries21. In addition, only people with severe forms of the disease used to be diagnosed and hospitalized in the first decade of this study, while diagnosis and hospitalization of milder cases have become more frequent in recent years, probably due to efficient medical educational programs9. Early diagnosis of leptospirosis has been associated to fewer complications and faster recovery from the infection8,20,22. Moreover, we have observed changes in the hemodynamic status and laboratory parameters, including a decrease in bilirubin levels and an increase in hemoglobin and platelet levels. Better hemodynamic status of the patients on admission, demonstrated by higher blood pressure levels, confirms the presence of the milder forms of the disease in the last decade. Hyperbilirubinemia is extremely common in leptospirosis patients, more frequently in association with skin rash, which usually leads to the presence of a „rubinic jaundice‟ pattern23. Elevated bilirubin levels and jaundice have been associated to death and poor outcomes in leptospirosis24,25,26, and their lower levels in the last decades among our patients also reflect a reduction in disease severity in our patients through the decades. Improvement in hematological parameters, including hemoglobin and platelet levels may be an evidence of a less severe infection and may have contributed to mortality decrease. Decrease in hemoglobin levels is a common finding in leptospirosis patients and it has been associated to severe disease and poor outcomes27,28. In addition, thrombocytopenia is also extremely frequent in leptospirosis patients and it is usually

10

associated to hemorrhagic phenomena and complications. It has been strongly associated to mortality and severity in leptospirosis and it has been included in a recent diagnostic scoring system for leptospirosis in a resource limited setting22,29. In a study carried out in Puerto Rico, elevated WBC levels was associated to fatal outcomes30. In our study, this elevation may result from a more severe disease presentation on admission and a possible secondary infection. The presence of arrhythmias is also a predictor of death in leptospirosis. Arrhythmias are the most common cardiac manifestation of leptospirosis and often derive from electrolyte disorders, such as hypokalemia and hypocalcemia, which are usually secondary to AKI31,32,33. Electrocardiographic abnormalities have been described as risk factors for death in leptospirosis patients12,20. Interestingly, patients in the present study had a significant linear reduction in serum urea and creatinine. They also showed a progressive reduction of severe AKI cases (KDIGO 3) in each decade, suggesting early diagnosis and treatment. Consequently, they also needed less renal replacement therapy over the last decades, a relevant factor that has contributed to the decrease in mortality, since AKI is strongly associated with higher risk of death in leptospirosis13,35,36. Leptospirosis is a significant cause of AKI in low and middle-income tropical countries37. AKI is also an important component of the severe form of leptospirosis (Weil‟s syndrome), leading to several complications. Referral to specialized care, including a nephrologist consultation, as well as early implementation of dialysis seems to be essential in slowing AKI progression to more severe forms and decreasing mortality38. Regarding AKI treatment, intermittent peritoneal dialysis (IPD) was the predominant method in the period from 1985 to 1996, used in 95.4% of patients that needed dialysis, and daily hemodialysis (DHD) was the most often used method in the period from 1997 to 2015. The institution

11

of early hemodialysis (<24h after AKI diagnosis) instead of IPD was essential for better prognosis of patients in the second and third decades of the study, with proven benefits in leptospirosis patients38. Furthermore, we hypothesize that the reduction in AKI development and AKI severity, as well as the establishment of an early and effective renal replacement therapy were key points in the reduction of mortality in our patients in recent years. Mortality showed a clear decrease trend in these three decades (decreasing from 22% to 14%, and then to 11.6% in the last decade), which probably reflects early diagnosis of complications and adequate treatment provision. Although previous studies had evidence that mortality does not seem to be significantly influenced by antibiotic use39,40, a recent study by our group showed that ceftriaxone was a protective factor for ICU admission in leptospirosis patients24. There is also evidence that the use of penicillin is associated with the reduction in hospital length of stay and fewer complications, including AKI39. We also have demonstrated that the use of antibiotics progressively increased throughout the decades (43.8%, 93.8% and 94.5%, p <0.0001) in our cohort, although it was not directly associated with mortality decline, according to the multivariate analysis. The use of antibiotics in leptospirosis is now a consensus in literature and we believe that its increase has probably contributed to mortality reduction, since it is associated with shorter length of hospital stay, milder AKI and less need for dialysis,39 as well as a lower frequency of intensive care admission24. In summary, leptospirosis is a life-threatening neglected tropical disease and its presentation has significantly modified in our region over time. The main changes point to a reduction in severity and complications, such as AKI. Mortality has shown a clear decrease trend in the last decades.

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STUDY LIMITATIONS The main limitations of this study derive from its retrospective design. Data from some patients‟ records were not available on admission. The study was carried out in only one region of Brazil, so disease patterns may differ in other Brazilian regions and worldwide.

ACKNOWLEDGEMENTS We are very grateful to the team of clinicians, medical residents, medical students and nurses from São José Infectious Diseases Hospital, Walter Cantídio University Hospital and Fortaleza General Hospital for the assistance provided to the patients and for the technical support provided for the development of thisresearch. Financial support: E. F. Daher and G. B. Silva Junior are recipients of a grant

from

the

Conselho

Nacional

de

Desenvolvimento

Científico

e

Tecnológico (CNPq). Disclaimer: The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

CONFLICTS OF INTEREST The authors declare no conflicts of interest regarding this manuscript.

REFERENCES

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10. Goswami RP, Goswami RP, Basu A, Tripathi SK, Chakrabarti S, Chattopadhyay I. Predictors of mortality in leptospirosis: an observational study from two hospitals in Kolkata, eastern India. Trans R Soc Trop Med Hyg 2014; 108: 791– 6. 11. Everard CO, Edwards CN, Everard JD, Carrington DG. A twelve-year study of leptospirosis on Barbados. Eur J Epidemiol 1995; 11: 311-20. 12. Daher E, Zanetta DM, Cavalcante MB, Abdulkader RC. Risk factors for death and changing patterns in leptospirosis acute renal failure. Am J Trop Med Hyg 1999; 61: 630-4. 13. Silva Junior GB, Abreu KL, Mota RM, Barreto AG, Araújo SM, Rocha HA, Libório AB, Daher EF, RIFLE and Acute Kidney Injury Network classifications predict mortality in leptospirosis-associated acute kidney injury. Nephrology (Carlton) 2011; 16: 269-76. 14. Kidney Disease Outcomes Quality Initiative. KDIGO clinical practice guidelines for acute kidney injury – Summary of recommendation statements. Kidney Int Suppl 2012; 2: 1-138. 15. Slack A. Leptospirosis. Aust Fam Physician 2010; 39: 495–8. 16. McBride AJ, Athanazio DA, Reis MG, Ko AI. Leptospirosis. Curr Opin Infect Dis 2005; 18: 376-86. 17. Ricaldi JN, Vinetz JM. Leptospirosis in the tropics and in travelers. Curr Infect Dis Rep 2006; 8: 51-8. 18. Waggoner JJ, Soda EA, Seibert R, Grant P, Pinsky BA. Molecular detection of Leptospira in two returned travelers: higher bacterial load in cerebrospinal fluid versus serum or plasma. Am J Trop Med Hyg 2015; 93: 238-40.

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19. Mikulski M, Boisier P, Lacassin F, Soupé-Gilbert MRE, Mauron C, BruyereOstells L et al. Severity Markers in severe leptospirosis. Eur J Clin Microbiol Infect Dis 2015; 34: 687-95. 20. Dupont H, Dupont-Perdrizet D, Perie JL, Zehner-Hansen S, Jarrige B, Daijardin JB. Leptospirosis: prognostic factors associated with mortality. Clin Infect Dis 1997; 25: 720-4. 21. Mwachui MA, Crump L, Hartskeerl R, Zinsstag J, Hattendorf J. Environmental and behavioural determinants of leptospirosis transmission: a systematic review. PLoS Negl Trop Dis 2015; 9: e0003843. 22. Spichler AS, Vilaça PJ, Athanazio DA, Albuquerque JO, Buzzar M, Castro B, et al. Predictors of lethality in severe leptospirosis in urban Brazil. Am J Trop Med Hyg 2008; 79: 911-4. 23. Puca E, Pilaca A, Kalo T, Pipero P, Bino S, Hysenaj Z et al. Ocular and cutaneous manifestation of leptospirosis acquired in Albania: A retrospective analysis with implications for travel medicine. Travel Med Infect Dis 2016; 14: 143-7. 24. Daher EF, Soares DS, de Menezes Fernandes ATB, Girão MMV, Sidrim PR, Pereira EDB, et al. Risk factors for intensive care unit admission in patients with severe leptospirosis: a comparative study according to patients‟ severity. BMC Infect Dis 2016; 16: 40. 25. Herrmann-Storck C, Saint-Louis M, Foucand T, Lamaury I, Deloumeaux J, Baranton G et al. Severe leptospirosis in hospitalized patients, Guadeloupe. Emerg Infect Dis 2010; 16: 331-4.

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26. Abgueguen P, Delbos V, Blanvillain J, Chennebault JM, Cottin J, Fanello S, et al. Clinical aspects and prognostic factors of leptospirosis in adults. J Infect 2008; 57: 171-8. 27. De Silva NL, Niloofa MJR, Fernando N, Karunanayake L., Rodrigo C, De Silva HJ et al. Changes in full blood count parameters in leptospirosis: a prospective study. Int Arch Med 2014; 7: 31. 28. Prabhu MV, Ramesh V. Fever, thrombocytopenia, and AKI-A profile of malaria, dengue, and leptospirosis with renal failure in a South Indian tertiary-care hospital. Clin Nephrol 2016; 86: 128-30. 29. Rajapakse S, Weeratunga P, Niloofa R, Fernando N, de Silva NL, Rodrigo C et al. A Diagnostic Scoring Model for Leptospirosis in Resource Limited Settings. PLoS Negl Trop Dis 2016; 10: e000451. 30. Sharp TM, García BR, Pérez-Padilla J, Galloway RL, GuerrA M., Ryff KR et al. Early Indicators of Fatal Leptospirosis during the 2010 Epidemic in Puerto Rico. PLoS Negl Trop Dis 2016; 10: e0004482. 31. Sacramento E, Lopes AA, Costa E, Passos OL, Costa YA, Matos ED. Electrocardiographic alterations in patients hospitalized with leptospirosis in the Brazilian city of Salvador. Arq Bras Cardiol 2002; 78: 267-70. 32. Navinan MR, Rajapakse S. Cardiac involvement in leptospirosis. Trans R Soc Trop Med Hyg 2012; 106: 515-20. 33. Soares DS, Galdino GS, Rodrigues BC, Silva Junior GB, Daher EF. Arrhythmias in leptospirosis-associated acute kidney injury: a case series. Braz J Infect Dis 2017; in press.

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34. Dupont H, Dupont-Perdrizet D, Perie JL, Zehner-Hansen S, Jarrige B, Daijardin JB. Leptospirosis: prognostic factors associated with mortality. Clin Infect Dis 1999; 25: 720-4. 35. Daher EF, Marques CN, Lima RSA, Silva Júnior GB, Barbosa AS, Barbosa ES, et al. Acute kidney injury in an infectious disease intensive care unit - an assessment of prognostic factors. Swiss Med Wkly 2008; 138: 128-33. 36. Teles F, de Mendonça Uchôa JV, Mendonça DMB, Costa AFP. Acute kidney injury in leptospirosis: the Kidney Disease Improving Global Outcomes (KDIGO) criteria and mortality. Clin Nephrol 2016; 86: 303–9. 37. Bouchard J, Mehta RL. Acute Kidney Injury in Western Countries. Kidney Dis (Basel) 2016; 2: 103-10. 38. Andrade L, Cleto S, Seguro AC. Door-to-Dialysis Time and Daily Hemodialysis in Patients with Leptospirosis: Impact on Mortality. Clin J Am Soc Nephrol 2007; 2: 739–44. 39. Daher EF, Silva GB, de Abreu KLS, Mota RMS, Batista DV, Rocha NA, et al. Leptospirosis-associated acute kidney injury: penicillin at the late stage is still controversial: Penicillin in leptospirosis. J Clin Pharm Ther 2012; 37: 420-5. 40. Costa E, Lopes AA, Sacramento E, Costa YA, Matos ED, Lopes MB, et al. Penicillin at the late stage of leptospirosis: a randomized controlled trial. Rev Inst Med Trop Sao Paulo 2003; 45: 141-5.

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Table 1. Comparison of demographic data between groups I, II and III

Age (years) Gender Male (%) Female (%) Hospital stay (days) Time between symptom onset and hospitalization (days) Mortality (%)

1985 – 1995 (N = 86) 43.2±17.8

1996 – 2005 (N = 187) 34.4±13.7

2006 – 2015 (N = 234) 37.3±16.2

66 (76.7) 20 (23.3) 13.2±8.7

151 (80.7) 336 (19.3) 8.1±5.0

201 (85.9) 33 (14.1) 11.1±8.2

7±2

7±3

7±5

22

14

11.6

p < 0.0001 0.121 < 0.0001 0.822

0.060

Analysis of variance (ANOVA). Values expressed as mean ± SD and percentage. P values ≤ 0.05 were considered statistically significant.

19

Table 2. Comparison of signs, symptoms, and vital signs between groups I, II and III 1985 – 1995 (N = 86)

1996 – 2005 (N = 187)

2006 – 2015 (N = 234)

P

17 (20) 57 (67) 56 (65.9) 12 (14) 51 (60) 18 (21.2) 84 (98.8) 10 (11.8)

6 (11) 90 (56.3) 129 (79.6) 36 (22.8) 93 (57.4) 4 (9.5) 141 (84.9) 12 (7.7)

1 (0.6) 57 (25.3) 132 (58.7) 20 (8.9) 41 (18.2) 0 (0) 126 (56) 9 (4)

<0.0001 <0.0001 <0.0001 0.001 <0.0001 <0.0001 <0.0001 0.041

78 (91.8) 11 (12.9) 17 (20) 1 (1.2) 20(23.5) 84 (98.8) 70 (82.4) 12 (14.1)

157 (94.6) 32 (20.8) 53 (33.5) 69 (42.3) 53 (33.3) 159 (95.8) 57 (80.3) 24 (45.3)

166 (73.8) 8 (3.6) 20 (8.9) 71 (31.6) 57(25.3) 205 (91) 109 (52.4) 21 (15.4)

<0.0001 <0.0001 <0.0001 <0.0001 0,143 0,019 <0.0001 <0.0001

110.0±20.3 66.5±16.1 -

108.1±19.7 67.4±14,2 97.3±17.3 26±8

116.4±21.3 72.3±15.4 96.6±18.4 26±10

0.001 0.002 0.786 0.716

Signs and symptoms

Arrhythmias (%) Chills (%) Headache (%) Crackles (%) Dehydration (%) Mental confusion (%) Jaundice (%) Secondary infections (%) Myalgia (%) Petechiae (%) Tachypnea (%) Dyspnea (%) Oligo/Anuria (%) Fever (%) Calf pain (%) Edema (%) Vital Signs

SBP (mmHg) DBP (mmHg) HR (/min) RR (/min)

SBP systolic blood pressure, DBP diastolic blood pressure, HR Heart Rate, RR Respiratory Rate. Analysis of variance (ANOVA). Values expressed as mean ± SD and percentage. P values ≤ 0.05 were considered statistically significant.

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Table 3. Comparison of laboratory data between patients from groups I, II and III Parameters Creatinine (mg/dL) Urea (mg/dL) Potassium (mEq/L) Sodium(mEq/L) AST (UI/L) ALT (UI/L) LDH (UI/L) CPK (UI/L) Direct bilirubin (mg/dL) Indirect bilirubin (mg/dL) Hematocrit (%) Hemoglobin (g/dL) WBC (103/mm3) Platelets (103/mm3) Serum pH Bicarbonate (mEq/L) SaO2 (%)

1985 – 1995 (N = 86) 5.8±2.9 190.1±92.7 4.0±1.0 75.5±54.5 51.9±33.5 595.7 ± 249.0 289.5±395.6 15.1±10.1 5.6±4.4 32.3±5.9 10.3±1.9 16.34±10.84 7.37±0.11 18.8±6.6 -

1996 – 2005 (N = 187) 3.8±2.6 135.3±79.5 3.6±1.1 132.3±6.3 141.1±145.3 102.4 ±122.9 719.7 ± 482.4 1358.5±3550 11.7 ±8.4 5.3±5.2 32.0±6.2 10.8±2.0 12.96±6.4 94.75 ± 82.73 7.36±0.08 18.8±4.4 93.0±8.9

2006 – 2015 (N = 234) 3.0±2.5 95.6±73.3 3.9±1.9 133.2±14.5 169.9±259.2 116.0 ±196.0 890.7 ± 634.8 1799±4163.7 5.5±6.3 2.56±4.0 34.2±21.8 11.5±2.1 13.6±14.2 123.048 ± 115.493 7.37±0.08 18.3±4.7 93.1±8.9

p <0.0001 <0.0001 0.019 0.583 0.006 0.019 0.048 0.164 <0.0001 <0.0001 0.376 <0.0001 0.110 0.021 0.747 0.668 0.944

AST - aspartate aminotransferase, ALT - alanine aminotransferase, LDH - lactate dehydrogenase, CPK – creatine phosphokinase, WBC - white blood cells, SaO2 - O2 saturation. Analysis of variance (ANOVA). Values expressed as mean ± SD. P values ≤ 0.05 were considered statistically significant.

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Table 4. Comparison of treatment instituted for patients with severe leptospirosis between groups I, II and III

Vasoconstrictors (%) Ceftriaxone (%) Penicillin (%) Diuretics (%) Need for dialysis (%) Hemodialysis (%) Peritoneal dialysis (%)

1985 – 1995 (N = 86)

1996 – 2005 (N = 187)

2006 – 2015 (N = 234)

P

1 (4.0) 9 (64.3) 7 (22.6) 3 (11.5) 65 (75.6 3 (4.6) 62 (95.4)

9 (31.0) 0 (0) 114 (82.6) 10 (34.5) 54 (29.5) 53 (98.1) 1 (1.9)

31 (16.1) 125 (67.9) 64 (28.4) 42 (21.8) 74 (31.6) 67 (90,5) 7 (9.5)

0.026 0.046 <0.0001 0.118 <0.0001 <0.0001 <0.0001

Analysis of variance (ANOVA). Values expressed as percentage. P values ≤ 0.05 were considered statistically significant.

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100%

p <0.001

90% 80% 70% 60% 50% 40%

KDIGO 1

30%

KDIGO 2

20%

KDIGO 3

10% 0% 1985 - 1995

1996 - 2005

2006 - 2015

Figure 1. AKI stages, according to KDIGO criteria, in patients with leptospirosis in three different decades.

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Figure 2. Mortality decrease in leptospirosis cases along the three-decade period.

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