ORIGINAL ARTICLE Miserachs et al. Diagnosis, Outcome, and Management of Chylous Ascites Following Pediatric Liver Transplantation Mar Miserachs ,1,2,5 Eberhard Lurz,1,6 Aviva Levman,1 Anand Ghanekar,3,4 Mark Cattral,3,4 Vicky Ng,1,2 David Grant,3,4 and Yaron Avitzur1,2 1 Transplant and Regenerative Medicine Centre and 2 Division of Pediatric Gastroenterology, Hepatology and Nutrition, Hospital for Sick Children, 3 Multi-Organ Transplant Program, University Health Network, and 4 Department of Surgery, University of Toronto, Toronto, Ontario, Canada; 5 Universitat Autònoma de Barcelona, Bellaterra, Spain; and 6 Division of Pediatric Gastroenterology, Hepatology and Nutrition, von Haunersches Kinderspitak, Ludwig Maximillians University Munich, Munich, Germany Data on postoperative chylous ascites (CA) after pediatric liver transplantation (LT) are scarce. This retrospective study was conducted to identify the incidence, risk factors, management, and outcomes of postoperative CA in a large single-center pediatric LT cohort (2000-2016). The study cohort comprised 317 LTs (153 living donors and 164 deceased donors) in 310 re- cipients with a median age of 2.7 years. The incidence of CA was 5.4% (n = 17), diagnosed after a median time of 10 days after LT. Compared with chylomicron detection in peritoneal fluid (the gold standard), a triglyceride cutoff value of 187 mg/dL in peritoneal fluid showed insufficient sensitivity (31%) for CA diagnosis. In univariate logistic regression analyses, ascites before LT, younger age, and lower weight, height, and height-for-age z score at LT were associated with CA. Symptomatic management of CA included peritoneal drain (100%) and diuretics (76%). Therapeutic interventions included very low-fat or medium-chain triglyceride–rich diets (94%) and intravenous octreotide (6%), leading to CA resolution in all patients. CA was associated with prolonged hospital length of stay (LOS; 40 days in the CA group versus 24 days in the non-CA group; P = 0.001) but not with reduced patient or graft survival rates after a median follow-up time of 14 years. In conclusion, CA in the pediatric LT recipient is a relatively uncommon complication associated with increased hospital LOS and morbidity. Measurement of chylomicrons is recommended in patients with ascites that is more severe or persistent than expected. Dietary interventions are effective in most patients. Liver Transplantation 25 1387‒1396 2019 AASLD. Received April 1, 2019; accepted June 25, 2019. Liver transplantation (LT) is an established curative disorders. Prevention of postoperative morbidity and treatment for children suffering from end-stage liver early directed therapy of immediate posttransplant disease, liver malignancies, and selected metabolic complications improves patient outcomes and sur- vival. Postoperative chylous ascites (CA), defined as the accumulation of lipid-rich lymph (chyle) in the peritoneal cavity, has rarely been studied in pediatric Abbreviations: A1AT, alpha-1-antitrypsin deficiency; CA, chylous LT recipients.(1-3) Continuous leakage of chyle into the ascites; CI, confidence interval; CMV, cytomegalovirus; EFA, essential fatty acid; IQR, interquartile range; LOS, length of stay; peritoneal cavity can lead to the loss of lymphocytes, LT, liver transplantation; MCT, medium-chain triglyceride; NPO, essential proteins, lipids, vitamins, electrolytes, and nil per os; OR, odds ratio; PFIC, progressive familial intrahepatic water.(4) The resultant clinical consequences beyond cholestasis; POD, postoperative day; TPN, total parenteral nutrition; the physical accumulation of ascites include dehydra- VAC, vacuum-assisted closure. tion, electrolyte imbalance, malnutrition, lymphope- Address reprint requests to Yaron Avitzur, M.D., Division of nia, and increased susceptibility to infection.(4,5) Pediatric Gastroenterology, Hepatology and Nutrition, Hospital for Sick Children, University of Toronto, 555 University Avenue, The diagnosis of postoperative CA in the pediat- Toronto, Ontario M5G 1X8, Canada. Telephone: 416-813-6176; ric LT recipient can be challenging. First, its clinical E-mail: yaron.avitzur@sickkids.ca presentation may mimic other posttransplant com- plications, such as hepatic arterial and portal venous Original Article | 1387 Miserachs et al. Liver Transplantation, September 2019 abnormalities, hepatic venous outflow obstruction, 2000 and December 2016. Infants and children receiv- small-for-size syndrome, and abdominal infection.(3,6) ing any organ in addition to liver, those transplanted at Second, diagnostic criteria for CA are not well estab- an outside institution, and those with CA diagnosed lished. Detection of chylomicrons by lipoprotein elec- prior to LT were excluded. LT recipients experiencing trophoresis in peritoneal fluid is considered the gold graft loss or death within 30 days following LT were standard diagnostic test.(7) When not available, a tri- also excluded. glyceride cutoff of 110 mg/dL (1.25 mmol/L) in peri- Data were retrieved from a prospectively populated toneal fluid was recommended in the pediatric LT electronic database and retrospective chart review. Data literature.(8) The latter recommendations were not sup- captured for all patients for risk analysis and outcome ported by high-quality evidence, and it is recognized reporting included demographics; primary diagnosis; that triglyceride quantification in peritoneal fluid may pretransplant comorbidities; surgical data; periopera- not be a reliable diagnostic criterion for CA in fast- tive morbidity, such as vascular thrombosis and biliary ing patients, particularly in the postoperative state.(9) complications; longterm outcomes, such as retrans- Recently, these gaps in the literature were addressed, plantation; and death. Height and weight z scores and it is now accepted that a triglyceride cutoff value were calculated using the World Health Organization of 187 mg/dL (2.13 mmol/L) establishes the diagnosis growth standards.(12) Additional data were collected of CA.(10) for all patients with CA and included information The optimal management of postoperative CA is regarding diagnosis, management, and outcome of unclear. One study in pediatric LT recipients reported CA. All study patients followed institutional protocols that dietary therapy is effective(11); another advo- for immunosuppression and received either standard cated for the use of pharmacologic therapy as a first- induction with corticosteroids and a calcineurin inhib- line therapy in high-volume output chylous leakage itor (tacrolimus) or a renal/neurotoxic-sparing protocol (>20 mL/kg/day).(8) Our study aimed to determine with corticosteroids and either antithymocyte globulin the incidence, risk factors, treatment, and outcomes of or 2 doses of basiliximab (Simulect; Novartis, Basel, postoperative CA in a large pediatric LT cohort using Switzerland) with a delayed introduction of calcineurin the detection of chylomicrons as the gold standard inhibitor agents.(13) The study received approval from diagnostic test and the newly established triglyceride the institutional research ethics board at the Hospital cutoff.(10) for Sick Children. DEFINITIONS AND OUTCOME Patients and Methods MEASURES STUDY POPULATION Ascites prior to LT was defined as the presence of a moderate-to-large amount of peritoneal fluid on The patient population in this case-control study abdominal ultrasound or history of diuretic use for the included all children younger than 18 years old who treatment of ascites prior to LT. Posttransplant CA was underwent LT surgery at the Hospital for Sick defined as the presence of chylomicrons or a triglycer- Children, Toronto, Ontario, Canada, between January ide value ≥187 mg/dL (≥2.13 mmol/L)(10) in the peri- toneal fluid within 60 days from LT in the absence of a positive peritoneal fluid culture. Triglyceride values of ≥148 and <187 mg/dL (≥1.69 and <2.13 mmol/L) This study was supported by the Transplant and Regenerative in the peritoneal fluid were considered equivocal for Medicine Centre, Hospital for Sick Children, University of Toronto, the diagnosis of CA.(10) Posttransplantation hospi- Toronto, Ontario, Canada. tal length of stay (LOS) was defined as the interval Copyright © 2019 by the American Association for the Study of Liver between the day of transplantation and the day of first Diseases. discharge from the hospital. View this article online at wileyonlinelibrary.com. DOI 10.1002/lt.25604 STATISTICAL ANALYSIS Potential conflict of interest: Nothing to report. Data were expressed as means and standard devi- ation or as median and interquartile range (IQR) 1388 | Original Article Liver Transplantation, Vol. 25, No. 9, 2019 Miserachs et al. when a nonnormal distribution of data was identi- INCIDENCE OF CA AND RISK fied. Student t test was used for continuous variables. ANALYSES A nonparametric test (Mann-Whitney U test) was used for continuous variables when an abnormal dis- A total of 17 patients with postoperative CA were tribution was identified. A chi-square test or Fisher’s identified, giving an incidence of 5.4% (95% CI, exact test was employed for categorical variables. The 2.9%-7.9%). Table 1 summarizes the demographic incidence of CA was calculated together with 95% and disease-specific data of the LT recipients with confidence interval (CI) limits. Patient survival rates and without CA. Age, weight, and height at LT were estimated with the Kaplan-Meier method and were significantly lower in LT recipients with CA compared with the log-rank test. Logistic regression compared with the non-CA group (P < 0.005). The univariate analyses were performed to explore the groups were comparable with respect to sex, under- association between CA and variables with clinical lying diagnosis, and liver graft type. Pediatric LT significance. Statistical analyses were performed recipients with CA had a significantly longer hospi- with SPSS, version 20.0 (SPSS Inc., Chicago, IL). tal LOS (CA group versus non-CA group; median A P value of <0.05 was considered statistically [IQR], 40.0 [28.8-51.2] versus 24.0 [16.0-38.8] days; significant. P = 0.001). The incidence of postoperative hepatic artery thrombosis and portal vein thrombosis within the first Results 3 months after LT showed no statistical difference between the CA and the non-CA group. Two cases of bile leak were diagnosed and treated through laparot- PATIENT CHARACTERISTICS omy prior to CA diagnosis. Although a trend toward The study cohort assembly is summarized in Fig. 1. higher bile leaks was noted in the CA group, this did The final study cohort comprised 317 isolated LTs not reach statistical significance (CA group versus performed in 310 pediatric patients with a median age non-CA group; 11.8% versus 3.3%; P = 0.20). The at LT of 2.8 years (IQR, 0.8-10.3 years) and a median incidence of CA per each of the 5 surgeons operating weight at LT of 13.8 kg (IQR, 8.0-29.8 kg). The me- during the study period was similar (P = 0.55). dian follow-up time of the whole cohort was 14.0 years The 1-, 3-, and 5-year actuarial patient survival for (IQR, 11.0-15.0 years). There were 48.3% living patients without CA was 99%, 94%, and 93%, respec- donor and 51.7% deceased donor (24.6% whole liver, tively, compared with 93%, 84%, and 84%, respectively, 14.2% reduced, and 12.9% split) grafts. Indications for patients with CA (P = 0.26; Fig. 2A). The 1-, 3-, for LT included biliary atresia (38.2%), Alagille syn- and 5-year actuarial graft survival (Fig. 2B) for patients drome (4.7%), other cholestatic liver diseases (10.4%), without CA was 98%, 93%, and 91%, respectively, metabolic diseases (17.4%), acute liver failure (14.5%), compared with 93%, 84%, and 84%, respectively, for malignancy (7.3%), and other (7.6%). patients with CA (P = 0.56). LT performed between January 1, 2000 and December 31, 2016 (ages 0-18 years at LT) n = 337 Excluded (n = 20): Insufficient data, n = 3 CA prior to LT, n = 4 LT included in the study Death within 30 days after LT, n = 6 n = 317 (310 patients) Graft loss within 30 days after LT, n = 7 LT with postoperative CA LT without postoperative CA n = 17 n = 300 FIG. 1. A flowchart of the study cohort assembly. Original Article | 1389 Miserachs et al. Liver Transplantation, September 2019 TABLE 1. Patient Characteristics and Surgical Parameters as a surrogate marker of nutritional status) were also of Patients With and Without Postoperative CA associated with the development of CA (Table 2). Postoperative No Postoperative CA CA (n = 17) (n = 300) P Value CHARACTERISTICS OF CA Age at LT, years 0.8 (0.4-3.1) 2.9 (0.8-10.7) 0.002* Median time to diagnosis of CA was 10.0 days (IQR, Sex, male 58.8 50.3 0.49 8.0-16.5 days) after LT surgery and 5.0 days (IQR, Underlying 0.61 3.0-12.0 days) after postoperative start of enteral feed- diagnosis ing. There were 7/17 patients who did not have surgical Biliary atresia 29.4 38.7 drains in place at the time of diagnosis, and fluid test- Other cholestasis 23.5 14.7 ing results were obtained by paracentesis (n = 5) or a Acute liver failure 23.5 14.0 vacuum-assisted closure (VAC) device (n = 2). Also, 7 Metabolic disease 17.6 17.3 patients developed pleural effusion that required drain- Other 6.0 15.3 age, and 2 of the patients had chyle detected in pleural Weight at LT, kg 8.2 (6.0-10.4) 14.6 (8.2-31.9) 0.001* fluid. Table 3 provides details on the 17 patients who Weight-for-age z −1.4 ± 1.9 −0.6 ± 1.5 0.05 score at LT developed postoperative CA within 60 days after LT. Height at LT, cm 66.6 (60.2-77.5) 91.0 (70.0-134.6) 0.001* Diagnosis of CA was biochemically evident through Height-for-age z −1.7 ± 2.0 −0.7 ± 1.4 0.007* chylomicron detection in 11 patients, triglycerides score at LT ≥187 mg/dL (≥2.13 mmol/L) in 1 patient not tested for Platelets, ×1000/mm3 152.0 (59.5-190.5) 146.5 (81.2-242) 0.51 chylomicrons, and both chylomicron detection and tri- Ascites before LT 76.5 32.7 0.001* glycerides ≥187 mg/dL (≥2.13 mmol/L) in the remain- Esophageal varices 23.5 18.7 0.62 ing 5 patients. Triglyceride levels in peritoneal fluid and/or variceal bleeding before LT were measured in all 17 patients with CA. Triglyceride Abdominal surgery 29.4 40.7 0.36 values were above the diagnostic cutoff value in 6/17 before LT patients, within the equivocal range for CA diagno- Re-LT 0 6.0 0.29 sis in 4/17 patients, and below the equivocal range in Graft type 0.21 7/17 patients. White cell count in peritoneal fluid was Living donor 70.6 47.0 >500 cells/mm3 in 10 of 14 cases analyzed. Median cell Split 11.8 13.0 count was 740 cells/mm3 (IQR, 396-1507 cells/mm3), Reduced 11.8 14.3 all with lymphocyte predominance (lymphocyte per- Whole 5.8 25.7 centage >80%). All patients had negative peritoneal Aortic conduit 0 7.0 0.26 fluid cultures at the time of CA diagnosis. reconstruction Surgical drain in situ 70.6 59.3 0.36 after LT MANAGEMENT AND OUTCOME Abdominal wall 0.57 OF CA closure Closed 76.5 89.3 A peritoneal drain was used in all patients with CA Mesh placement 5.9 3.3 for symptomatic management of ascites. Median dura- VAC device 11.8 7.0 tion of CA from diagnosis to the time of drain removal was 15.0 days (IQR, 11.5-22.5 days), with 2 patients NOTE: Data are shown as mean ± standard deviation, median (IQR), or %. draining for 30 days or more. Drain reinsertion after *Significant P values. removal was not required in any of the patients. In total, 13/17 patients received diuretics. Dietary modifications were used in 15/17 children and In univariate analyses, ascites before transplantation included a very low-fat diet for 2 patients who were able was identified as a significant risk factor for the devel- to take solid food by mouth, low-fat formula (Tolerex) in opment of CA after LT with an odds ratio (OR) of 6.69. 1 patient, and medium-chain triglyceride (MCT)–rich Young age at transplantation (OR = 1.26 per year), formula (Portagen; Mead Johnson Nutrition, Evansville, lower weight at transplantation (OR = 1.10 per kg), USA) in 13 patients. Diet modifications were main- lower height at transplantation (OR = 1.04 per cm), tained for a median of 49.0 days (IQR, 27.0-72.0 days). and lower height-for-age z score at LT (OR = 1.59; Total parenteral nutrition (TPN) and nil per os (NPO) 1390 | Original Article Liver Transplantation, Vol. 25, No. 9, 2019 Miserachs et al. FIG. 2. The posttransplant survival outcomes. (A) Patient and (B) graft survival rates in patients with or without CA. TABLE 2. Summary of Univariate Logistic Regression in 4/17 patients within the first 90 postoperative days Models Evaluating the Effect of Independent Variables on (PODs). Severe lymphopenia (<0.5 × 109/L) was noted the Development of CA in 7/17 LT recipients with CA within 3 months after OR 95% CI P Value LT. Lymphopenia resolved in all patients except in 1 patient, for whom resolution could not be confirmed Age (younger) at LT because of the transfer to another institution and death. Overall (per year) 1.26 1.04-1.54 0.02* There were 4/17 children with postoperative CA who ≤1 year 2.90 1.07-7.84 0.04* received treatment for 5 documented infections follow- Weight (lower) at LT ing the diagnosis of CA and within 3 months after LT: Overall (per kg) 1.10 1.01-1.19 0.02* cytomegalovirus (CMV) viremia (n = 1), urinary tract ≤10 kg 6.04 1.92-18.97 0.002* infection (Enterococcus spp.; n = 1), peritonitis while Weight-for-age z score 1.38 0.99-1.91 0.05 (lower) at LT the peritoneal drain remained in situ (Enterobacter spp.; Height (lower) at LT (per cm) 1.04 1.01-1.06 0.01* n = 1), upper respiratory tract infection (parainfluenza Height-for-age z score 1.59 1.13-2.24 0.01* type 3; n = 1), and pneumonia (coronavirus; n = 1). (lower) at LT All children in the CA group except 1, who was Platelet count (lower) at LT 1.00 1.00-1.01 0.37 transferred to another institution to receive palliative (per platelets x1000/mm3) care, were discharged home after a median of 40.0 days Ascites before LT 6.69 2.12-21.07 0.001* (IQR, 28.8-51.2 days). Within 30 days of discharge, Surgical drain in situ after LT 1.63 0.56-4.74 0.37 2/16 patients were rehospitalized: 1 for pneumonia *Significant P values. and 1 for biopsy-proven liver allograft acute cellular rejection. Also, 2 deaths occurred in the CA group was used in 4 patients for a median of 7.5 days (IQR, 4.5- due to posttransplant recurrence of hepatoblastoma 9.8 days). Octreotide for 8 days at a maximum dose of and hemophagocytic lymphohistiocytosis at 4 and 4 µg/kg/hour was added to the low-fat formula (Tolerex; 6 months after LT, respectively. Société des Produits Nestlé S.A., Vevey, Switzerland) in 1 patient for whom nutritional therapy failed to reduce chylous leakage volumes (Table 3). Biopsy-proven liver allograft acute cellular rejec- Discussion tion, defined as the rejection activity index according The findings of this large pediatric cohort reveal that to the Banff schema ≥3 (range, 0-9), was diagnosed postoperative CA is an uncommon complication in Original Article | 1391 TABLE 3. Clinical Course of Children With CA After LT 1392 Demographics at LT Diagnosis of CA Management Outcomes <3 Months After LT | Peritoneal Fluid Findings Time of Peritoneal Patient Age and Primary Diagnosis After Chylomicron Triglyceride, Drain Duration, Postoperative Number Sex Weight Diagnosis LT, days Detection mmol/L days Treatment Diuretics Complications Infection LOS, days Miserachs et al. 1 Male 0.2 years Neonatal liver 12 + 7.73 20 Portagen, + Bile leak and 33 6.4 kg failure 11 days relaparotomy POD 4 2 Female 3 years Hepatoblastoma 8 Not tested 3.34 13 NPO/TPN, + * 23.2 kg 4 days 3 Male 7 years Acute liver 15 + 1.79 16 NPO/TPN, + Bile leak and 46 27.4 kg failure 2 days relaparotomy Low-fat diet, POD 4 Original Article 27 days 4 Female 1 year Biliary atresia 19 + 2.77 13 Portagen, − 31 8.9 kg 12 days 5 Male 0.7 years Acute liver 10 + 2.14 5 Portagen, − 123 6.5 kg failure 90 days 6 Female 0.4 years Biliary atresia 7 + 0.86 15 + 28 6.2 kg 7 Male 3 years Alagille 13 + 0.90 16 Portagen, − 25 11.8 kg syndrome 29 days 8 Male 0.2 years Neonatal liver 21 + 1.08 25 Portagen, + CMV viremia and uri- 53 4.5 kg failure 121 days nary tract infection (Enterococcus spp.) 9 Male 1 year PFIC 1 18 + 1.10 35 Portagen, + Peritonitis 87 8.2 kg 61 days (Enterobacter spp.) 10 Male 0.3 years Biliary atresia 8 + 1.40 15 Portagen, + Upper respiratory tract 27 5.5 kg 86 days infection (parainfluenza type 3) 11 Female 0.4 years Biliary atresia 8 + 0.63 26 NPO/TPN, + 43 5.8 kg 9 days Portagen, 13 days 12 Male 0.8 years Biliary atresia 7 + 2.02 3 NPO/TPN, − 28 8.4 kg 6 days Portagen, 40 days Liver Transplantation, September 2019 TABLE 3. Continued Demographics at LT Diagnosis of CA Management Outcomes <3 Months After LT Peritoneal Fluid Findings Time of Peritoneal Patient Age and Primary Diagnosis After Chylomicron Triglyceride, Drain Duration, Postoperative Number Sex Weight Diagnosis LT, days Detection mmol/L days Treatment Diuretics Complications Infection LOS, days 13 Female 2 years PFIC 1 8 + 3.51 45 NPO/TPN, + 63 8.9 kg 10 days Portagen, 11 days Tolerex, 38 days Octreotide, 8 days (added to Liver Transplantation, Vol. 25, No. 9, 2019 Tolerex) 14 Female 5 years A1AT 23 + 1.77 12 Low-fat diet, + 37 20.9 kg 56 days 15 Male 0.7 years A1AT 8 + 3.14 13 Portagen, + 36 6.2 kg 67 days 16 Female 0.2 years Neonatal liver 12 + 1.94 11 Portagen, + Viral pneumonia 45 4 kg failure 37 days (coronavirus) 17 Male 0.9 years Alagille 8 + 1.42 7 Portagen, + 46 8.5 kg syndrome 72 days *Patient 2 was transferred to another institution for palliative care after primary disease recurrence (death occurred 4 months after LT). Original Article | 1393 Miserachs et al. Miserachs et al. Liver Transplantation, September 2019 children after LT, leads to a prolonged hospital LOS and lymphatic structures in younger children, putting and immediate postoperative morbidity, but does not small children at a greater risk for traumatic injury of impact longterm graft and patient survival. In all of the lymphatic vessels during surgery. Similarly, a lower our cases, early recognition of CA and symptomatic height-for-age z score at LT, which generally implies management of ascites using a peritoneal drain and failure to thrive and malnutrition, was also signifi- dietary interventions (MCT-rich formula/very low-fat cantly associated with a higher risk of postoperative diet/NPO and TPN if there is no response to formula) CA. These results support reports describing pretrans- led to the resolution of CA, with only 1 patient receiv- plant malnutrition in children as a risk factor for post- ing pharmacologic therapy. transplant morbidity.(17) Given that the weight-for-age The incidence of CA in our study population (5.4%) z score may underestimate the degree of undernutri- is similar to values reported in other mixed pediatric tion in children with chronic liver disease because of and adult studies (6.3%) and adult studies (4.7%).(8,14) the effects of organomegaly and/or ascites, it is not sur- Yet, a recent study describing a series of 120 pediat- prising that no association was found between weight- ric LTs reported a CA incidence of 24%.(3) The reason for-age z score at LT and postoperative CA. for the incidence discrepancy is unclear and proba- Concurrent with the initiation of enteral feeding, bly relates to different practices around surgical drain postoperative CA manifests primarily with persistent insertion and peritoneal fluid testing. The rate of sur- ascites or milky drainage through surgical drains in gical drain insertion was lower in our study (60.1%) situ, often in the setting of otherwise adequate graft compared with that reported by Marseglia et al.(3) function. CA should be an integral part of the dif- (87.5%). In addition, only 15% of our study patients ferential diagnosis of early ascites after transplant were investigated for chylomicrons in the peritoneal in addition to other common postoperative compli- fluid, raising the possibility that only symptomatic CA cations, such as hepatic arterial and portal venous was diagnosed in our and other cohorts with similar abnormalities, hepatic venous outflow obstruction, incidence. small-for-size syndrome, and abdominal infec- In our cohort, the development of ascites prior to tion.(3,6) Suspicion of CA should prompt further transplantation, a sign of decompensated cirrhosis, investigation to confirm the diagnosis. Detection was associated with a higher risk for the development of chylomicrons in peritoneal fluid, obtained either of CA. Lymphangiogenesis has been described in the through the peritoneal drain or through paracentesis, context of cirrhosis, and it has been speculated that it is considered the gold standard test for the diagnosis may help accommodate increased lymphatic flows and of CA. elevated portal pressures.(15,16) It is possible that the Recently, a triglyceride cutoff of ≥187 mg/dL increased lymphatic circulation in patients with cir- (≥2.13 mmol/L) in peritoneal fluid was suggested rhosis contributes to an increased risk of traumatic CA as an additional diagnostic tool for CA.(10) In our during LT; however, evidence supporting this hypoth- study, 16/17 and 30/300 LT recipients in the CA and esis is lacking. Our findings are in keeping with those non-CA groups, respectively, were investigated for reported by Yilmaz et al.,(14) who also identified devel- both chylomicrons and triglycerides in the perito- opment of ascites prior to LT as an independent risk neal fluid. We found the recently proposed triglycer- factor for CA. Nonetheless, a smaller study reported ide cutoff to be insufficiently sensitive (31.25%) as that children and young adult LT recipients with post- a diagnostic tool. These findings suggest that the operative CA had similar rates of ascites on pretrans- triglyceride cutoff may not be a reliable criterion to plant radiological imaging as those without CA.(8) The exclude the diagnosis of CA in fasting or partially fed main difference between this study and ours lies in the pediatric LT recipients. Maldonado et al. reported timing of the identification of ascites (anytime preop- similar findings when determining the biochemical eratively in the latter), without being clear whether LT parameters of chylous pleural fluid in patients with recipients in the first study had previously developed chylothorax, particularly in those fasting in the post- ascites. operative state.(9) Peritoneal fluid should also be sent Our analysis yielded additional risk factors for the for cell count (lymphocyte predominance) and cul- development of postoperative CA, namely, age ≤1 year ture (negative). and weight ≤10 kg at time of transplantation. These There is a lack of consensus regarding the opti- findings may be related to the smaller caliber of vascular mal management of postoperative CA, and treatment 1394 | Original Article Liver Transplantation, Vol. 25, No. 9, 2019 Miserachs et al. options range from nutritional interventions to pharma- should be sought in children with increased perito- cologic treatments and surgical procedures.(1,8,11,18-20) neal drain losses or ascites after LT, particularly in In contrast to what other groups have reported, in the younger population with a history of ascites and/ our series, we relied on symptomatic management of or malnutrition before LT. Chylomicron detection the ascites with diuretics and/or insertion of a peri- in peritoneal fluid appears to be a more sensitive test toneal drain and nutritional interventions to manage that overran arbitrary triglyceride cutoff values in chil- CA.(1,8,18) Large peritoneal drain losses were generally dren undergoing LT. Symptomatic management of replaced with 5% intravenous albumin (ratio of 1:1 CA with peritoneal drains and dietary interventions or less), and drains were clamped when fluid output are highly effective first-line treatment modalities in <5 mL/kg/day was reached. In our series, abdomi- the majority of patients. Routine use of octreotide is nal infection (bacterial peritonitis) occurred in only 1 not recommended or required. Early recognition and patient and was easily managed. treatment of this unusual complication will shorten Nutritional interventions were used in 16 patients hospital LOS and reduce the degree of postoperative and included dietary fat modifications in 11 children morbidity. and dietary fat modifications plus a period of fasting and parenteral nutrition in 5 patients for whom dietary REFERENCES fat modification failed to diminish peritoneal drain losses. 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