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Trends in surgical management of urachal anomalies
Journal of Pediatric Surgery 50 (2015) 1334–1337
Contents lists available at ScienceDirect
Journal of Pediatric Surgery journal homepage: www.elsevier.com/locate/jpedsurg
Trends in surgical management of urachal anomalies☆,☆☆ Joshua K. Stopak a,⁎, Kenneth S. Azarow b, Shahab F. Abdessalam c, Stephen C. Raynor c, Deborah A. Perry d, Robert A. Cusick c a
Department of Anesthesiology, University of Vermont Medical Center, Burlington, VT, 05401, USA Department of Surgery, Oregon Health and Science University, Portland, OR, 97239, USA Department of Pediatric Surgery, Children’s Hospital and Medical Center, Omaha, NE, 68114-4113, USA d Department of Pathology, Children’s Hospital & Medical Center, Omaha, NE, 68114, USA b c
a r t i c l e
i n f o
Article history: Received 11 April 2014 Received in revised form 26 April 2015 Accepted 30 April 2015 Key words: Urachus Urachal anomalies Infection Non-operative management
a b s t r a c t Purpose: We have noted an increasing frequency of diagnosed urachal anomalies. The purpose of this study is to evaluate this increase, as well as the outcomes of management at our institution over 10 years. Methods: A retrospective analysis of urachal anomalies at our institution was performed. Inclusion criteria were Anomalies of Urachus (ICD 753.7) or Urinary Anomaly NOS (ICD 753.9) between January 2000 and December 2010. Exclusion criteria were having an asymptomatic urachal remnant incidentally excised. Results: Eighty-five patients (49 male, 36 female) presented between 0 and 17 years of age (mean 1.5 years). Diagnoses increased from 0 in 2000 to 21 in 2010. Zero was surgically managed in 2000 while 21 were managed in 2010 (p = 0.0145). Fifteen patients (17.6%) were observed with 13 (13/15, or 15.3%) resolving without complication while 2 were operated on. Average time to resolution (clinical or radiologic) was 4.9 months (Range: 0.4–12.6). A total of seventy-two patients (84.7%) underwent excision. Thirty-nine (54%) surgical cases were outpatient while 33 (46%) were admitted. Thirteen (18%) had post-operative complications. Ten (77%) of the complications were wound infections. Patients under 6 months of age accounted for 60% (6 of 10) of all wound infections and 52% (17 of 33) of hospitalizations. Conclusions: Our experience and review of the literature suggest a high complication rate with surgical management in young patients, mostly from infections and support non-operative management of all non-infected urachal remnants in children. © 2015 Elsevier Inc. All rights reserved.
The urachus is an embryonic connection between the urinary bladder and the allantois, which obliterates to form the median umbilical ligament in utero [1]. Failure to obliterate at any point can lead to urachal anomalies (UAs). Due to the risk of infection and malignant degeneration later in life, surgical excision has been the standard of care [2–8]. Conservative management of UAs has been increasingly recommended, especially in younger children [9–12]. At our institution, we have noted an increasing frequency of urachal anomalies diagnosed. The purpose of this study was to review our 10-year experience with urachal anomaly management at Children’s Hospital and Medical Center of Omaha, Nebraska and the current diagnostic and treatment modalities. We further analyzed children under 6 months of age in order to determine their outcomes, given that some have recommended conservative therapy for this age group [13].
☆ Level of Evidence: Level 3 ☆☆ Disclosure: The authors have no conflicts of interests to disclose. ⁎ Corresponding author. Tel.: +1 402 980 6917; fax: +1 402 955 7405. E-mail address: [email protected] (J.K. Stopak). http://dx.doi.org/10.1016/j.jpedsurg.2015.04.020 0022-3468/© 2015 Elsevier Inc. All rights reserved.
1. Methods A retrospective case-series was performed with patients from Omaha Children’s Hospital and Medical Center. All charts between January 2000 and December 2010 with a diagnosis of Anomalies of Urachus (ICD 753.7) or Urinary Anomaly NOS (ICD 753.9) were reviewed. 460 records were reduced to 369 after removal of duplicates. 278 cases were then excluded for having no actual history of an urachus, while 6 additional cases were removed because they were an incidental, asymptomatic urachal remnant excised at the time of another procedure. The remaining 85 cases were evaluated in this study. Fifteen patients were followed until radiographic or clinic resolution; however, 2 failed observation and went on to surgery. At the discretion of the individual surgeon, 72 total patients underwent surgical excision of an urachal anomaly. Cases were evaluated by sex, age at diagnosis, initial presentation, diagnostic modalities utilized, radiographic findings, infectious organisms isolated, outcomes of operative and non-operative care, complications, histological findings, and duration of hospitalization. Statistical analysis was performed using linear regression analysis and Fisher’s Exact Test. Linear regression examined the increase in frequency of the cases diagnosed and operated on during the testing period. Fisher’s Exact was used to evaluate the relationship between patient age, post-operative wound infections, and antibiotic usage. Approval
J.K. Stopak et al. / Journal of Pediatric Surgery 50 (2015) 1334–1337
for this study was received from the University of Nebraska Medical Center and Children's Hospital Institutional Review Board. 2. Results 2.1. Demographics (see Table 1) Eighty-five patients were identified with urachal anomalies with a male to female ratio of 1.36. Diagnoses increased from 0 to 21 during the study period (See Fig. 1). From 2000 to 2002 there were no patients diagnosed with urachal anomalies. Three patients were diagnosed in 2003. Two of those patients underwent surgical excision while 1 was observed, again at the discretion of the individual surgeon. These patients presented between January and November 2003. Linear regression analysis of cases diagnosed vs. time during the study period yielded a p-value b 0.0001 (R2 = 0.67 and t = 22.61). Linear regression analysis of cases operated on vs. time yielded a p-value b 0.0001 (R2 = 0.62 and t = 18.50). 2.2. Presentation These 85 patients presented in a variety of manners: forty-three patients (51%) with drainage, 20 (24%) with an umbilical polyp/ granulation, 16 (19%) with an infected urachus, 1 (1%) with an umbilical cord cyst, 1 (1%) with a patent urachal fistula, and 4 (5%) were found incidentally on radiography performed for other reasons (1 VCUG for neurogenic bladder, and 3 during screening US for multiple congenital anomalies). Of the 16 patients that presented with an infected urachus, Staphylococcus aureus was isolated in 9 (56%) cases, Enterococcus spp. in 1 (6%), and Escherichia coli in 1(6%) case. No organism was identified in 5 (31%) of the 16 cases. 2.3. Imaging Sixty patients underwent ultrasonography, 17 had a voiding cystourethrogram (VCUG), 7 underwent computed tomography (CT), and 1 patient had a sinogram performed. Some patients underwent more than one imaging study. 24 patients had no diagnostic imaging performed and were operated on based on history and physical exam. The single patient with a patent fistula had a sonogram to confirm the diagnosis. Sensitivities for US, VCUG, and CT were found to be 95%, 5.9%, and 85.7% respectively.
Table 1 Presenting demographics. N = 85 (%) Sex Male Female M:F Age (months) at diagnosis Mean
49 (58) 36 (42) 1.36
1st Quartile 2nd Quartile 3rd Quartile 4th Quartile Median Primary Presenting Symptom Drainage Umbilical Polyp/Granulation Infection Fistula Umbilical Cord Cysts Incidental Radiographic Finding
17.7 0.7 1.6 8.3 215.7 1.6 43 (51) 20 (24) 16 (19) 1 (1) 1 (1) 4 (5)
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2.4. Pathology Pathology specimens were available for review for 70 of the 72 surgical patients. Two of the patients did not have pathology slides available for review in our system. Gross examination revealed a patent tubular structure in 2 of the specimens confirmed under microscopic examination. A tubular structure/remnant without a patent lumen on gross examination was present in an additional 39 specimens. Microscopic examination confirmed microscopic tubular elements, or epithelial remnants, in these 39 specimens. An inflamed tract was present in 10 of the specimens. No dysplastic change or malignancy was identified. 2.5. Outcomes Fifteen patients (17.6%) with urachal remnants were initially treated with a conservative approach of observation. Two patients failed this conservative approach and eventually required excision for persistence of umbilical drainage and irritation. There were no adverse outcomes in this group. The remaining 13 patients in the conservative group were followed to resolution by ultrasonography (n = 6) or clinical criteria (n = 7). Clinical criteria were defined as resolution of drainage and local irritation. Thus the success rate for conservative management via observation is 87% and the failure rate 13%. Mean follow-up time for the 7 cases that resolved by clinical criteria was 6.2 months, while mean follow-up time for the 6 that resolved by radiographic findings was 3.4 months (range 0.4–12.6 months). Seventy-two patients with urachal remnants, including the 2 who failed observation, underwent operative management (Fig. 2). Thirtynine (54%) surgical cases were performed as outpatient, while 33 (46%) were admitted. Seventeen (24%) patients were hospitalized overnight due to a low post-conceptual age, while 16 (22%) were kept overnight for other reasons: requiring antibiotics for infection (n = 10), tracheomalacia (n = 1), concurrent surgical procedures (n = 2), and unknown (n = 3). A total of 38 (53%) surgical patients received preoperative antibiotics, leaving 34 (47%) that did not. There were 13 (18%) surgical patients with post-operative complications, of which 10 were wound infections, 2 were persistent drainage, while one was a persistent granuloma and stitch abscess. Twenty-three percent (3/13) of patients with a complication required a second surgery to resolve their complication. Sixty percent of wound infections (6/10) occurred in patients who did not receive peri-operative antibiotics. 2.6. Age b 6 months There were 61 (72%) of all patients who were less than 6 months of age. These patients comprised 60% (6/10) of wound infections and 52% (17/33) of overnight hospitalizations. One patient less than 6 months of age also required a second trip to the OR to remove a granuloma resistant to conservative therapy. Of those 7 patients less than 6 months of age who developed a complication, 3 (43%) received pre-operative antibiotics, while 4 (57%) did not. Patients less than 6 months of age also comprised 92% (12/15) of patients whose UA resolved with observation alone. 3. Discussion The urachus begins to elongate during the 4th and 5th gestational months in utero as the embryonic bladder descends into the pelvis and eventually obliterates into a fibrous remnant. The time that it actually begins to obliterate remains quite controversial. This structure lies in the space of Retzius between transversalis fascia and preperitoneum [5,11,13,14]. Persistence of the urachus after birth can occur at any point along the tract extending from the dome of the bladder to the umbilicus [10,11,15, 6]. Types of urachal remnants include a cyst, sinus, patent urachus, and bladder diverticulum (Fig. 2). Cysts are the most commonly reported anomaly, while a sinus is second in frequency followed by a patent urachus. [5,12,13,17–19].
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Fig. 1. Frequency of urachal anomaly diagnosis and management.
Urachal anomalies have been historically considered to be a rare occurrence; however, a wide range is reported in the literature: 1:5000 to 1:3 adults at autopsy. Pediatric reports are also varied, ranging from 3:1,168,760 up to 1.6% of all children who underwent screening ultrasound [11,20–23]. More recently, with improved ultrasonography, it has been suggested that urachal remnants in children is physiologically normal and usually resolves with age [11,24,25]. Our hospital saw a dramatic increase in urachal anomalies during the study period. During the study time period, our hospital saw a 28.9% increase in surgical cases from 6571 cases in 2000 to 8467 in 2010. Additionally, the pediatric population (ages 0–17 years) increased in the state by 2.0%, rising from 450,242 in 2000 to 459,221 in 2010. The increase in the number of urachuses diagnosed in the ten-year study period was much greater than the increase in the pediatric population of 2.0%. During this time period there were several upgrades in ultrasound equipment, which led to greater visualization of urachal remnants. Therefore, the increase in the diagnosis in our series over the ten-year period is likely due to increased awareness in community pediatricians and an increased detection with improved ultrasonography, rather than an increase in operative volume. Symptomatic urachal remnants can present in several different ways. Umbilical drainage is the most common, followed by abdominal pain, umbilical mass, omphalitis, abscess, or dysuria [5,12,13]. In our series, umbilical drainage was the most common chief complaint. The most common reported organism in patients with omphalitis has been reported to be S. aureus, followed by E. coli [5,13,16,18]. Our series supports current literature as S. aureus accounted for 56% of all cultured organisms of the 16 patients who presented with an infected urachus. The next most common organisms were E. coli and Enterococcus spp., which accounted for 6% of cultured organisms, each. Therefore, antibiotic usage should provide adequate coverage for S. aureus. Diagnostic imaging studies are often used to identify urachal anomalies. Ultrasonography is currently the imaging study of choice and has been reported to have a sensitivity of 79%–91%, while other studies such as VCUG, CT, and sinogram have been shown to have sensitivities of 33%–50%, 75%, and 100% respectively [5,12,19]. The usefulness of VCUG has been questioned in the literature and is no longer considered part of the standard evaluation of urachal anomalies [16,26,27]. VCUG was determined to have a sensitivity of 5.9% in our report. Given the low sensitivity in our series, and the invasiveness of the procedure, we would also support that VCUG should not be part of the standard
evaluation of urachal anomalies. If other urologic abnormalities are suspected, a VCUG may be indicated. Computed tomography has been used when US findings are negative or questionable, as was the case in our series. Given the increased lifetime cancer risk, and limited additional information gained, CT should be reserved for ambiguous ultrasound results [28]. Surgical management has remained the standard of care, in order to avoid infection, as well as to prevent malignant degeneration later in life [29]. No causal link between a childhood urachal remnant and development of an urachal adenocarcinoma later in life has been established [13]. Furthermore, urachal adenocarcinoma is exceedingly rare, especially when one considers that up to 62% of children under 16 years of age may have an urachal remnant, and that urachal neoplasms comprise, at most, only 0.34% of all bladder cancers [11,19,25,30]. There were no pathology specimens from the 70 available that showed dysplastic change on pathologic examination. Review of the literature has also not yielded an absolute risk of malignancy of an untreated UR. Additionally, surgery is not without risk. Reported post-operative complication rates range from 3% to 14.7% [5,12,31]. Comparatively, we report a complication rate of 18%. This may be due to our broad
Fig. 2. Urachal remnant mobilized after division of umbilical arteries and umbilical veins.
J.K. Stopak et al. / Journal of Pediatric Surgery 50 (2015) 1334–1337
definition of “complication.” Also, urachal excisions were treated as “clean” cases in many instances at our institution, receiving preoperative antibiotics only 53% (38/72) of the time, at the discretion of the surgeon. The infection rate observed in our series (14%) is within the upper limits of the literature range of 3%–14.7%. Given this infection rate, routine antibiotic usage should be considered [5,12,32]. Conservative management of urachal remnants is reported in the literature in case reports, as well as a few small series [9–11,13,25,31,33]. Additionally, our data suggest that the natural course of many of these urachal remnants is spontaneous resolution, with 87% of patients in the observation group resolving without complication within about 1 year of diagnosis. Initial observation may also be safe, as we had no significant cases of omphalitis resulting from a UA at presentation or from conservative management. Some in the literature recommend withholding surgical management until 6–12 months of age, even for patients who present with infection responsive to antibiotics [9–11,13,33]. With these recommendations in mind, we noted that 68% of surgical patients in our series were under 6 months of age and that those patients accounted for 25% of overnight hospitalizations and 60% of wound infections. If presentation is simply drainage and local irritation, we recommend observation. If symptoms return, reevaluation is indicated. This might include simply an exam or a repeat ultrasound. There are several limitations to our study. The sample size of the patients with urachal remnants that were observed and did not undergo surgery was quite small. With more widespread acceptance of conservative management more complications might occur (recurrent infections). Second, given the retrospective nature of the study and the individual surgeons deciding which patients were observed it is difficult to determine which patients may be safely observed. Finally, it was difficult to determine the primary etiology for the high infection rate we observed. It might be the lack of preoperative antibiotics given in many patients, the young age at intervention, or simply the nature of disease. In conclusion, at our institution, we have seen the number of urachal anomalies dramatically increase over the past 10 years. Ultrasonography should be used for the initial evaluation of a suspected UA. Due to the complication rate in young patients, coupled with the chance of spontaneous resolution, and weighed against the need for overnight hospitalization, most UAs can be managed non-operatively for the first 6–12 months of life. Early intervention (b6 months) should be reserved for patient with documented urine draining from the urachus or a documented abscess. Additionally, should patients require excision of a UA, pre-operative antibiotics should be considered given the high rate of post-operative infections.
References [1] Razvi S, Murphy R, Shlasko E, et al. Delayed separation of the umbilical cord attributable to urachal anomalies. Pediatrics 2001;108:493–4.
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[2] Rich RH, Hardy BE, Filler RM. Surgery for the anomalies of the urachus. J Pediatr Surg 1983;18:370–2. [3] Agatstein EH, Stabile BE. Peritonitis due to intraperitoneal perforation of infected urachal cyst. Arch Surg 1984;119:269–1273. [4] Horgan PG, Johnson S, Courtney D. Intraperitoneal rupture of an infected urachus. Br J Urol 1997;73:216. [5] McCollum MO, Macneily AE, Blair GK. Surgical implications of urachal remnants: presentation and management. J Pediatr Surg 2003;38(5):798–803. [6] Bourne CW, May JE. Urachal remnants: benign or malignant? J Urol 1977;118: 743–7. [7] Sheldon CA, Clayman RV, Gonzalez R, et al. Malignant urachal lesions. J Urol 1984; 131:1–8. [8] Rubin JP, Kasznica JM, Davis CA, et al. Transitional cell carcinoma in a urachal cyst. J Urol 1999;162:1687–8. [9] Cuda SP, Vanasupa BP, Sutherland RS. Nonoperative management of a patent urachus. Urology 2005;66(6):1320e7–9. [10] Lipskar AM, Glick RD, Rosen NG, et al. Nonoperative management of symptomatic urachal anomalies. J Pediatr Surg 2010;45:1016–9. [11] Ueno T, Hashimoto H, Yokoyama H, et al. Urachal anomalies: ultrasonography and management. J Pediatr Surg 2003;38:1203–7. [12] Yiee JH, Garcia N, Baker LA, et al. A diagnostic algorithm for urachal anomalies. J Pediatr Urol 2007;3:500–4. [13] Galati V, Donovan B, Ramji F, et al. Management of urachal remnants in early childhood. J Urol 2008;180:1824–7. [14] Baier R, Rumstadt B. Laparoscopic resection of urachal fistula. Surg Laparosc Endosc Percutan Tech 2001;21(4):295–6. [15] Begg RC. The urachus: its anatomy, histology and development. J Anat 1930;67: 170–83. [16] Little DC, Shah SER, St Peter SD, et al. Urachal anomalies in children: the vanishing relevance of the preoperative voiding cystourethrogram. J Pediatr Surg 2005;40:1874–6. [17] Blichert-Toft M, Nielsen OV. Congenital patent urachus and acquired variants. Diagnosis and treatment. Review of the literature and report of 5 cases. Acta Chir Scand 1971;137:807–14. [18] Mesrobian HG, Zacharias A, Balcom AH, et al. Ten years of experience with isolated urachal anomalies in children. J Urol 1997;158:1316–8. [19] Widni EE, Hollwarth ME, Haxhija EQ. The impact of preoperative ultrasound on correct diagnosis of urachal remnants in children. J Pediatr Surg 2010;45:1433–7. [20] Bermann SM, Tolia BM, Laor E, et al. Urachal remnants in adults. Urology 1988;31: 17–21. [21] Schubert GE, Pavkovic MB, Bethke-Bedurftig BA. Tubular urachal remnants in adult bladders. J Urol 1982;127(1):40–2. [22] Rubin A. A handbook of congenital malformations. Philadelphia, PA: Saunders; 1967. [23] Nix JT, Menville JG, Albert M, et al. Congenital patent urachus. J Urol 1958;79(2): 264–73. [24] Zieger B, Sokol B, Rohrschneider WK, et al. Sonomorphology and involution of the normal urachus in asymptomatic newborns. Pediatr Radiol 1998;28(3):156–66. [25] Robert Y, Henne quin-Delerue C, Chaillet D, et al. Urachal remnants: sonographic assessment. J Clin Ultrasound 1996;24(7):339–44. [26] Walsh PC, Retik AB, Vaughan ED, et al. Campbell’s urology. 7th ed. Philadelphia: WB Saunders; 1998 1984–7. [27] Cilento Jr BG, Bauer SB, Retik AB, et al. Urachal anomalies: defining the best diagnostic modality. Urology 1998;52:120–2. [28] Miglioretti DL, Johnson E, Williams A, et al. The use of computed tomography in pediatrics and the associated radiation exposure and estimated cancer risk. JAMA Pediatr 2013;10:1–8. http://dx.doi.org/10.1001/jamapediatrics.2013.311 [Epub ahead of print]. [29] Ashley RA, Inman BA, Routh JC, et al. Urachal anomalies: a longitudinal study of urachal remnants in children and adults. J Urol 2007;178:1615–8. [30] Yu HH, Leong CH. Carcinoma of the urachus: report of one case and review of literature. Surgery 1975;77(5):726–9. [31] Naiditch JA, Radhakrishnan J, Chin AC. Current diagnosis and management of urachal remnants. J Pediatr Surg 2013;48:2148–52. [32] Ortega G, Rhee DS, Papandria DJ, et al. An evaluation of surgical site infections by wound classification system using the ACS-NSQIP. J Surg Res 2012;174(1):33–8. [33] Yohannes P, Bruno T, Pathan M, et al. Laparoscopic radical excision of urachal sinus. J Endourol 2003;17(7):475–9.
Contents lists available at ScienceDirect
Journal of Pediatric Surgery journal homepage: www.elsevier.com/locate/jpedsurg
Trends in surgical management of urachal anomalies☆,☆☆ Joshua K. Stopak a,⁎, Kenneth S. Azarow b, Shahab F. Abdessalam c, Stephen C. Raynor c, Deborah A. Perry d, Robert A. Cusick c a
Department of Anesthesiology, University of Vermont Medical Center, Burlington, VT, 05401, USA Department of Surgery, Oregon Health and Science University, Portland, OR, 97239, USA Department of Pediatric Surgery, Children’s Hospital and Medical Center, Omaha, NE, 68114-4113, USA d Department of Pathology, Children’s Hospital & Medical Center, Omaha, NE, 68114, USA b c
a r t i c l e
i n f o
Article history: Received 11 April 2014 Received in revised form 26 April 2015 Accepted 30 April 2015 Key words: Urachus Urachal anomalies Infection Non-operative management
a b s t r a c t Purpose: We have noted an increasing frequency of diagnosed urachal anomalies. The purpose of this study is to evaluate this increase, as well as the outcomes of management at our institution over 10 years. Methods: A retrospective analysis of urachal anomalies at our institution was performed. Inclusion criteria were Anomalies of Urachus (ICD 753.7) or Urinary Anomaly NOS (ICD 753.9) between January 2000 and December 2010. Exclusion criteria were having an asymptomatic urachal remnant incidentally excised. Results: Eighty-five patients (49 male, 36 female) presented between 0 and 17 years of age (mean 1.5 years). Diagnoses increased from 0 in 2000 to 21 in 2010. Zero was surgically managed in 2000 while 21 were managed in 2010 (p = 0.0145). Fifteen patients (17.6%) were observed with 13 (13/15, or 15.3%) resolving without complication while 2 were operated on. Average time to resolution (clinical or radiologic) was 4.9 months (Range: 0.4–12.6). A total of seventy-two patients (84.7%) underwent excision. Thirty-nine (54%) surgical cases were outpatient while 33 (46%) were admitted. Thirteen (18%) had post-operative complications. Ten (77%) of the complications were wound infections. Patients under 6 months of age accounted for 60% (6 of 10) of all wound infections and 52% (17 of 33) of hospitalizations. Conclusions: Our experience and review of the literature suggest a high complication rate with surgical management in young patients, mostly from infections and support non-operative management of all non-infected urachal remnants in children. © 2015 Elsevier Inc. All rights reserved.
The urachus is an embryonic connection between the urinary bladder and the allantois, which obliterates to form the median umbilical ligament in utero [1]. Failure to obliterate at any point can lead to urachal anomalies (UAs). Due to the risk of infection and malignant degeneration later in life, surgical excision has been the standard of care [2–8]. Conservative management of UAs has been increasingly recommended, especially in younger children [9–12]. At our institution, we have noted an increasing frequency of urachal anomalies diagnosed. The purpose of this study was to review our 10-year experience with urachal anomaly management at Children’s Hospital and Medical Center of Omaha, Nebraska and the current diagnostic and treatment modalities. We further analyzed children under 6 months of age in order to determine their outcomes, given that some have recommended conservative therapy for this age group [13].
☆ Level of Evidence: Level 3 ☆☆ Disclosure: The authors have no conflicts of interests to disclose. ⁎ Corresponding author. Tel.: +1 402 980 6917; fax: +1 402 955 7405. E-mail address: [email protected] (J.K. Stopak). http://dx.doi.org/10.1016/j.jpedsurg.2015.04.020 0022-3468/© 2015 Elsevier Inc. All rights reserved.
1. Methods A retrospective case-series was performed with patients from Omaha Children’s Hospital and Medical Center. All charts between January 2000 and December 2010 with a diagnosis of Anomalies of Urachus (ICD 753.7) or Urinary Anomaly NOS (ICD 753.9) were reviewed. 460 records were reduced to 369 after removal of duplicates. 278 cases were then excluded for having no actual history of an urachus, while 6 additional cases were removed because they were an incidental, asymptomatic urachal remnant excised at the time of another procedure. The remaining 85 cases were evaluated in this study. Fifteen patients were followed until radiographic or clinic resolution; however, 2 failed observation and went on to surgery. At the discretion of the individual surgeon, 72 total patients underwent surgical excision of an urachal anomaly. Cases were evaluated by sex, age at diagnosis, initial presentation, diagnostic modalities utilized, radiographic findings, infectious organisms isolated, outcomes of operative and non-operative care, complications, histological findings, and duration of hospitalization. Statistical analysis was performed using linear regression analysis and Fisher’s Exact Test. Linear regression examined the increase in frequency of the cases diagnosed and operated on during the testing period. Fisher’s Exact was used to evaluate the relationship between patient age, post-operative wound infections, and antibiotic usage. Approval
J.K. Stopak et al. / Journal of Pediatric Surgery 50 (2015) 1334–1337
for this study was received from the University of Nebraska Medical Center and Children's Hospital Institutional Review Board. 2. Results 2.1. Demographics (see Table 1) Eighty-five patients were identified with urachal anomalies with a male to female ratio of 1.36. Diagnoses increased from 0 to 21 during the study period (See Fig. 1). From 2000 to 2002 there were no patients diagnosed with urachal anomalies. Three patients were diagnosed in 2003. Two of those patients underwent surgical excision while 1 was observed, again at the discretion of the individual surgeon. These patients presented between January and November 2003. Linear regression analysis of cases diagnosed vs. time during the study period yielded a p-value b 0.0001 (R2 = 0.67 and t = 22.61). Linear regression analysis of cases operated on vs. time yielded a p-value b 0.0001 (R2 = 0.62 and t = 18.50). 2.2. Presentation These 85 patients presented in a variety of manners: forty-three patients (51%) with drainage, 20 (24%) with an umbilical polyp/ granulation, 16 (19%) with an infected urachus, 1 (1%) with an umbilical cord cyst, 1 (1%) with a patent urachal fistula, and 4 (5%) were found incidentally on radiography performed for other reasons (1 VCUG for neurogenic bladder, and 3 during screening US for multiple congenital anomalies). Of the 16 patients that presented with an infected urachus, Staphylococcus aureus was isolated in 9 (56%) cases, Enterococcus spp. in 1 (6%), and Escherichia coli in 1(6%) case. No organism was identified in 5 (31%) of the 16 cases. 2.3. Imaging Sixty patients underwent ultrasonography, 17 had a voiding cystourethrogram (VCUG), 7 underwent computed tomography (CT), and 1 patient had a sinogram performed. Some patients underwent more than one imaging study. 24 patients had no diagnostic imaging performed and were operated on based on history and physical exam. The single patient with a patent fistula had a sonogram to confirm the diagnosis. Sensitivities for US, VCUG, and CT were found to be 95%, 5.9%, and 85.7% respectively.
Table 1 Presenting demographics. N = 85 (%) Sex Male Female M:F Age (months) at diagnosis Mean
49 (58) 36 (42) 1.36
1st Quartile 2nd Quartile 3rd Quartile 4th Quartile Median Primary Presenting Symptom Drainage Umbilical Polyp/Granulation Infection Fistula Umbilical Cord Cysts Incidental Radiographic Finding
17.7 0.7 1.6 8.3 215.7 1.6 43 (51) 20 (24) 16 (19) 1 (1) 1 (1) 4 (5)
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2.4. Pathology Pathology specimens were available for review for 70 of the 72 surgical patients. Two of the patients did not have pathology slides available for review in our system. Gross examination revealed a patent tubular structure in 2 of the specimens confirmed under microscopic examination. A tubular structure/remnant without a patent lumen on gross examination was present in an additional 39 specimens. Microscopic examination confirmed microscopic tubular elements, or epithelial remnants, in these 39 specimens. An inflamed tract was present in 10 of the specimens. No dysplastic change or malignancy was identified. 2.5. Outcomes Fifteen patients (17.6%) with urachal remnants were initially treated with a conservative approach of observation. Two patients failed this conservative approach and eventually required excision for persistence of umbilical drainage and irritation. There were no adverse outcomes in this group. The remaining 13 patients in the conservative group were followed to resolution by ultrasonography (n = 6) or clinical criteria (n = 7). Clinical criteria were defined as resolution of drainage and local irritation. Thus the success rate for conservative management via observation is 87% and the failure rate 13%. Mean follow-up time for the 7 cases that resolved by clinical criteria was 6.2 months, while mean follow-up time for the 6 that resolved by radiographic findings was 3.4 months (range 0.4–12.6 months). Seventy-two patients with urachal remnants, including the 2 who failed observation, underwent operative management (Fig. 2). Thirtynine (54%) surgical cases were performed as outpatient, while 33 (46%) were admitted. Seventeen (24%) patients were hospitalized overnight due to a low post-conceptual age, while 16 (22%) were kept overnight for other reasons: requiring antibiotics for infection (n = 10), tracheomalacia (n = 1), concurrent surgical procedures (n = 2), and unknown (n = 3). A total of 38 (53%) surgical patients received preoperative antibiotics, leaving 34 (47%) that did not. There were 13 (18%) surgical patients with post-operative complications, of which 10 were wound infections, 2 were persistent drainage, while one was a persistent granuloma and stitch abscess. Twenty-three percent (3/13) of patients with a complication required a second surgery to resolve their complication. Sixty percent of wound infections (6/10) occurred in patients who did not receive peri-operative antibiotics. 2.6. Age b 6 months There were 61 (72%) of all patients who were less than 6 months of age. These patients comprised 60% (6/10) of wound infections and 52% (17/33) of overnight hospitalizations. One patient less than 6 months of age also required a second trip to the OR to remove a granuloma resistant to conservative therapy. Of those 7 patients less than 6 months of age who developed a complication, 3 (43%) received pre-operative antibiotics, while 4 (57%) did not. Patients less than 6 months of age also comprised 92% (12/15) of patients whose UA resolved with observation alone. 3. Discussion The urachus begins to elongate during the 4th and 5th gestational months in utero as the embryonic bladder descends into the pelvis and eventually obliterates into a fibrous remnant. The time that it actually begins to obliterate remains quite controversial. This structure lies in the space of Retzius between transversalis fascia and preperitoneum [5,11,13,14]. Persistence of the urachus after birth can occur at any point along the tract extending from the dome of the bladder to the umbilicus [10,11,15, 6]. Types of urachal remnants include a cyst, sinus, patent urachus, and bladder diverticulum (Fig. 2). Cysts are the most commonly reported anomaly, while a sinus is second in frequency followed by a patent urachus. [5,12,13,17–19].
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Fig. 1. Frequency of urachal anomaly diagnosis and management.
Urachal anomalies have been historically considered to be a rare occurrence; however, a wide range is reported in the literature: 1:5000 to 1:3 adults at autopsy. Pediatric reports are also varied, ranging from 3:1,168,760 up to 1.6% of all children who underwent screening ultrasound [11,20–23]. More recently, with improved ultrasonography, it has been suggested that urachal remnants in children is physiologically normal and usually resolves with age [11,24,25]. Our hospital saw a dramatic increase in urachal anomalies during the study period. During the study time period, our hospital saw a 28.9% increase in surgical cases from 6571 cases in 2000 to 8467 in 2010. Additionally, the pediatric population (ages 0–17 years) increased in the state by 2.0%, rising from 450,242 in 2000 to 459,221 in 2010. The increase in the number of urachuses diagnosed in the ten-year study period was much greater than the increase in the pediatric population of 2.0%. During this time period there were several upgrades in ultrasound equipment, which led to greater visualization of urachal remnants. Therefore, the increase in the diagnosis in our series over the ten-year period is likely due to increased awareness in community pediatricians and an increased detection with improved ultrasonography, rather than an increase in operative volume. Symptomatic urachal remnants can present in several different ways. Umbilical drainage is the most common, followed by abdominal pain, umbilical mass, omphalitis, abscess, or dysuria [5,12,13]. In our series, umbilical drainage was the most common chief complaint. The most common reported organism in patients with omphalitis has been reported to be S. aureus, followed by E. coli [5,13,16,18]. Our series supports current literature as S. aureus accounted for 56% of all cultured organisms of the 16 patients who presented with an infected urachus. The next most common organisms were E. coli and Enterococcus spp., which accounted for 6% of cultured organisms, each. Therefore, antibiotic usage should provide adequate coverage for S. aureus. Diagnostic imaging studies are often used to identify urachal anomalies. Ultrasonography is currently the imaging study of choice and has been reported to have a sensitivity of 79%–91%, while other studies such as VCUG, CT, and sinogram have been shown to have sensitivities of 33%–50%, 75%, and 100% respectively [5,12,19]. The usefulness of VCUG has been questioned in the literature and is no longer considered part of the standard evaluation of urachal anomalies [16,26,27]. VCUG was determined to have a sensitivity of 5.9% in our report. Given the low sensitivity in our series, and the invasiveness of the procedure, we would also support that VCUG should not be part of the standard
evaluation of urachal anomalies. If other urologic abnormalities are suspected, a VCUG may be indicated. Computed tomography has been used when US findings are negative or questionable, as was the case in our series. Given the increased lifetime cancer risk, and limited additional information gained, CT should be reserved for ambiguous ultrasound results [28]. Surgical management has remained the standard of care, in order to avoid infection, as well as to prevent malignant degeneration later in life [29]. No causal link between a childhood urachal remnant and development of an urachal adenocarcinoma later in life has been established [13]. Furthermore, urachal adenocarcinoma is exceedingly rare, especially when one considers that up to 62% of children under 16 years of age may have an urachal remnant, and that urachal neoplasms comprise, at most, only 0.34% of all bladder cancers [11,19,25,30]. There were no pathology specimens from the 70 available that showed dysplastic change on pathologic examination. Review of the literature has also not yielded an absolute risk of malignancy of an untreated UR. Additionally, surgery is not without risk. Reported post-operative complication rates range from 3% to 14.7% [5,12,31]. Comparatively, we report a complication rate of 18%. This may be due to our broad
Fig. 2. Urachal remnant mobilized after division of umbilical arteries and umbilical veins.
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definition of “complication.” Also, urachal excisions were treated as “clean” cases in many instances at our institution, receiving preoperative antibiotics only 53% (38/72) of the time, at the discretion of the surgeon. The infection rate observed in our series (14%) is within the upper limits of the literature range of 3%–14.7%. Given this infection rate, routine antibiotic usage should be considered [5,12,32]. Conservative management of urachal remnants is reported in the literature in case reports, as well as a few small series [9–11,13,25,31,33]. Additionally, our data suggest that the natural course of many of these urachal remnants is spontaneous resolution, with 87% of patients in the observation group resolving without complication within about 1 year of diagnosis. Initial observation may also be safe, as we had no significant cases of omphalitis resulting from a UA at presentation or from conservative management. Some in the literature recommend withholding surgical management until 6–12 months of age, even for patients who present with infection responsive to antibiotics [9–11,13,33]. With these recommendations in mind, we noted that 68% of surgical patients in our series were under 6 months of age and that those patients accounted for 25% of overnight hospitalizations and 60% of wound infections. If presentation is simply drainage and local irritation, we recommend observation. If symptoms return, reevaluation is indicated. This might include simply an exam or a repeat ultrasound. There are several limitations to our study. The sample size of the patients with urachal remnants that were observed and did not undergo surgery was quite small. With more widespread acceptance of conservative management more complications might occur (recurrent infections). Second, given the retrospective nature of the study and the individual surgeons deciding which patients were observed it is difficult to determine which patients may be safely observed. Finally, it was difficult to determine the primary etiology for the high infection rate we observed. It might be the lack of preoperative antibiotics given in many patients, the young age at intervention, or simply the nature of disease. In conclusion, at our institution, we have seen the number of urachal anomalies dramatically increase over the past 10 years. Ultrasonography should be used for the initial evaluation of a suspected UA. Due to the complication rate in young patients, coupled with the chance of spontaneous resolution, and weighed against the need for overnight hospitalization, most UAs can be managed non-operatively for the first 6–12 months of life. Early intervention (b6 months) should be reserved for patient with documented urine draining from the urachus or a documented abscess. Additionally, should patients require excision of a UA, pre-operative antibiotics should be considered given the high rate of post-operative infections.
References [1] Razvi S, Murphy R, Shlasko E, et al. Delayed separation of the umbilical cord attributable to urachal anomalies. Pediatrics 2001;108:493–4.
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[2] Rich RH, Hardy BE, Filler RM. Surgery for the anomalies of the urachus. J Pediatr Surg 1983;18:370–2. [3] Agatstein EH, Stabile BE. Peritonitis due to intraperitoneal perforation of infected urachal cyst. Arch Surg 1984;119:269–1273. [4] Horgan PG, Johnson S, Courtney D. Intraperitoneal rupture of an infected urachus. Br J Urol 1997;73:216. [5] McCollum MO, Macneily AE, Blair GK. Surgical implications of urachal remnants: presentation and management. J Pediatr Surg 2003;38(5):798–803. [6] Bourne CW, May JE. Urachal remnants: benign or malignant? J Urol 1977;118: 743–7. [7] Sheldon CA, Clayman RV, Gonzalez R, et al. Malignant urachal lesions. J Urol 1984; 131:1–8. [8] Rubin JP, Kasznica JM, Davis CA, et al. Transitional cell carcinoma in a urachal cyst. J Urol 1999;162:1687–8. [9] Cuda SP, Vanasupa BP, Sutherland RS. Nonoperative management of a patent urachus. Urology 2005;66(6):1320e7–9. [10] Lipskar AM, Glick RD, Rosen NG, et al. Nonoperative management of symptomatic urachal anomalies. J Pediatr Surg 2010;45:1016–9. [11] Ueno T, Hashimoto H, Yokoyama H, et al. Urachal anomalies: ultrasonography and management. J Pediatr Surg 2003;38:1203–7. [12] Yiee JH, Garcia N, Baker LA, et al. A diagnostic algorithm for urachal anomalies. J Pediatr Urol 2007;3:500–4. [13] Galati V, Donovan B, Ramji F, et al. Management of urachal remnants in early childhood. J Urol 2008;180:1824–7. [14] Baier R, Rumstadt B. Laparoscopic resection of urachal fistula. Surg Laparosc Endosc Percutan Tech 2001;21(4):295–6. [15] Begg RC. The urachus: its anatomy, histology and development. J Anat 1930;67: 170–83. [16] Little DC, Shah SER, St Peter SD, et al. Urachal anomalies in children: the vanishing relevance of the preoperative voiding cystourethrogram. J Pediatr Surg 2005;40:1874–6. [17] Blichert-Toft M, Nielsen OV. Congenital patent urachus and acquired variants. Diagnosis and treatment. Review of the literature and report of 5 cases. Acta Chir Scand 1971;137:807–14. [18] Mesrobian HG, Zacharias A, Balcom AH, et al. Ten years of experience with isolated urachal anomalies in children. J Urol 1997;158:1316–8. [19] Widni EE, Hollwarth ME, Haxhija EQ. The impact of preoperative ultrasound on correct diagnosis of urachal remnants in children. J Pediatr Surg 2010;45:1433–7. [20] Bermann SM, Tolia BM, Laor E, et al. Urachal remnants in adults. Urology 1988;31: 17–21. [21] Schubert GE, Pavkovic MB, Bethke-Bedurftig BA. Tubular urachal remnants in adult bladders. J Urol 1982;127(1):40–2. [22] Rubin A. A handbook of congenital malformations. Philadelphia, PA: Saunders; 1967. [23] Nix JT, Menville JG, Albert M, et al. Congenital patent urachus. J Urol 1958;79(2): 264–73. [24] Zieger B, Sokol B, Rohrschneider WK, et al. Sonomorphology and involution of the normal urachus in asymptomatic newborns. Pediatr Radiol 1998;28(3):156–66. [25] Robert Y, Henne quin-Delerue C, Chaillet D, et al. Urachal remnants: sonographic assessment. J Clin Ultrasound 1996;24(7):339–44. [26] Walsh PC, Retik AB, Vaughan ED, et al. Campbell’s urology. 7th ed. Philadelphia: WB Saunders; 1998 1984–7. [27] Cilento Jr BG, Bauer SB, Retik AB, et al. Urachal anomalies: defining the best diagnostic modality. Urology 1998;52:120–2. [28] Miglioretti DL, Johnson E, Williams A, et al. The use of computed tomography in pediatrics and the associated radiation exposure and estimated cancer risk. JAMA Pediatr 2013;10:1–8. http://dx.doi.org/10.1001/jamapediatrics.2013.311 [Epub ahead of print]. [29] Ashley RA, Inman BA, Routh JC, et al. Urachal anomalies: a longitudinal study of urachal remnants in children and adults. J Urol 2007;178:1615–8. [30] Yu HH, Leong CH. Carcinoma of the urachus: report of one case and review of literature. Surgery 1975;77(5):726–9. [31] Naiditch JA, Radhakrishnan J, Chin AC. Current diagnosis and management of urachal remnants. J Pediatr Surg 2013;48:2148–52. [32] Ortega G, Rhee DS, Papandria DJ, et al. An evaluation of surgical site infections by wound classification system using the ACS-NSQIP. J Surg Res 2012;174(1):33–8. [33] Yohannes P, Bruno T, Pathan M, et al. Laparoscopic radical excision of urachal sinus. J Endourol 2003;17(7):475–9.