Chyluria: a mimicker of nephrotic syndrome

BACKGROUND AND OBJECTIVE: Chyluria can be confused with nephrotic syndrome when massive proteinuria is present on urine examination during evaluation of a milky/white urine. Our objective was to attempt to resolve diagnosis in the case of nephrotic range proteinuria when there is no clear evidence of a significant kidney lesion. DESIGN AND SETTING: Retrospective review of the medical records of all patients referred the nephrology department at a single institution. PATIENTS AND METHODS: We identified a subgroup of patients misdiagnosed with nephrotic syndrome and treated aggressively with immunosupression with no benefit and who were later diagnosed as having chyluria. RESULTS: Twelve patients were identified (8 men, 4 women) with a median age of 34.5 years. Chyle was positive in the urine in eight while chyle was positive on oral ingestion of butterfat in another 4. Six had undergone kidney biopsy and were treated as having minimal change disease. Eight had massive proteinuria and a history of treatment with prednisone, but none of these patients had shown improvement in their clinical presentation. Two patients showed excellent results with diethylcarbamazine with angiotensin-converting enzyme inhibitors in while eight required betadine instillation in the fistulous connection with success in six. Surgical correction was successfully tried in two of these resistant cases. CONCLUSION: In individuals with nephrotic range proteinuria with a normal or low lipid profile status along with normal serum albumin levels, urine color and nature, frequency, and checking the urine for chyle can help identify the large subgroup who unnecessarily have to undergo kidney biopsy and at times are treated with immunosuppression, which is not only life threatening but useless in these patients.