INTRODUCTION:Chylous ascites, an uncommon disorder of infancy and childhood, is usually caused by neoplasms, particularly lymphomas, liver cirrhosis, superior vena cava thrombosis, nephrotic syndrome, dilated cardiomyopathy and right heart failure.
CASE PRESENTATION:The patient is a 2.5 month old male who presented to the emergency room in respiratory failure and hyponatremic dehydration. He was diagnosed three days earlier with RSV by rapid ELISA at an outside institution. He was born at 30 weeks gestation; intubated for 2 days and remained in the NICU for 3 weeks. Discharged home on room air, he gained weight well on Neosure. On the day of admission he had decreased oral intake, fewer wet diapers and increased sleepiness. On evaluation his SaO2= 70%, with lethargy, hypotonia and poor respiratory effort and perfusion. He was intubated and admitted to the PICU. (Figure1) On PRVC his oxygenation index was 33 and improved to 25 with nitric oxide. High frequency oscillation was utilized following fluid resuscitation and cardiovascular support with dopamine and norepinephrine. Echocardiogram was normal. Laboratories on admission were notable for: Na =127; K=6.4; Cl =86; HCO3=26, BUN=23 Creat=1.2; Albumin=2.8; WBC= 2.9 (Diff- 10 PMN/ 74 Lymph/ 12 Mono); Hgb=13.5. Infectious evaluation yielded a respiratory culture with E. coli and H. influenza. BUN and creatinine improved and once hemodynamically stable, was started on continuous Neosure feeds via nasoduodenal access. His weight increased significantly with generalized thick non-pitting edema. The hypoalbumenemia persisted despite albumin and diuretic infusions; his BUN/creat rose to 57/0.9. Following an abdominal ultrasound showing ascites, a temporary peritoneal catheter was placed for dialysis(PD) facilitating fluid balance. Upon placement, chylous fluid was drained. (97% lymphs, peripheral 5%)(Figure2). Pancreatitis and hypothyroidism were ruled out. Bilateral small pleural fluid collections were drained and revealed chylous characteristics. Portagen was begun and within two days the triglycerides in the peritoneal fluid plummeted from 2200 to 30 mg/dl and peripheral lymphocyte count began to rise. The BUN/creat and edema responded appropriately to continuous PD. Upon cessation, his lymphocyte count returned to normal .He was extubated on HD#27 and off oxygen on HD#31. Hospital course complicated by Klebsiella pneumoniae line sepsis. Discharged to complete a six-week course of Portagen feeds. Lymphocyte count, albumin and abdominal girth remained normal. He is thriving and gaining weight appropriately. Abdominal ultrasound and CT scan of the abdomen, pelvis and thorax prior to discharge showed no evidence of lymphadenopathy, ascites or intestinal or vascular obstruction. Since well on normal formula, mother didn’t consent for lymphscintography.
DISCUSSIONS:Chylous effusions are uncommon in children. Congenital malformations of lymphatic system like congenital lymphangiomatosis, chylous cysts and atresia of the lymphatic ducts are responsible for 39% of cases. Idiopathic causes account for 30% of cases and patients present with leaky lymphatics, apparently caused by delayed maturation or hypoplasia of lacteals allowing chyle to leak into cavities. Lymphangiectasia can result in chylous ascites or chylothorax. Secondary causes of chylous ascites are due to inflammation, neoplasia, trauma, mechanical obstruction . The most common causes of chylothorax are cancer and trauma but subclavian vein cannulation, with or without thrombosis, is well-described. In infants, imaging is often unrevealing including CT scan, lymphangioscintography,and MR lymphangiography.
CONCLUSION:The etiology of our patient’s chylous ascites remains a question. The chylous ascites resolved with medium chain triglycerides formula. Following a six-week period of rest for the abdominal lymphatics, he tolerated reintroduction of long chain fats. Causes may have been high peak airway pressures or placement of an internal jugular venous catheter which can cause thoracic duct obstruction. There was no evidence of this and the chylothorax was minor relative to the chylous ascites.
DISCLOSURE:Denise Nunez, None.