Dr Ning Zhang1,2, Dr Jane Rigg3, Dr Craig Peter Coorey1,2,4, Dr William James1
1Department of Nephrology, Lismore Base Hospital, Lismore, Australia, 2Sydney Medical School, University of Sydney, Sydney, Australia, 3Department of General Medicine, Lismore Base Hospital, Lismore, Australia , 4School of Medicine, University of Western Sydney, Campbelltown, Australia
Biography:
Dr Ning Zhang is a Basic Physician Trainee with the Northern Sydney Coastal Network, having worked at Lismore Base Hospital, Royal North Shore Hospital and Gosford Hospital. She has previous experience working in Obstetrics and Gynaecology as an SRMO and has interests in Obstetric Medicine.
Abstract:
Background: New onset nephrotic-range proteinuria in pregnancy prompts investigation for pre-eclampsia and underlying glomerulopathies. Non-parasitic chyluria is a rare cause of nephrotic range proteinuria and not often considered. We report an interesting case of a pregnant patient with episodes of nephrotic-range proteinuria and chyluria on a background of minimal change disease.
Case Report: A 26-year-old woman, gravid 0, para 0, 19+1 weeks gestation, presented to the Emergency Department following a pre-syncopal episode and described having 4 weeks of cloudy urine. She had a background medical history of biopsy-proven minimal change disease. Her only medications were multivitamins. She had no history of overseas travel.
Her examination was unremarkable with no signs of volume overload. Her investigations revealed normal renal function with nephrotic-range proteinuria (protein/creatinine ratio 1325 mg/mmol). She was positive for COVID-19. The following day a repeat urine had a normalised protein/creatinine ratio. The possibility of chyluria was considered given the milky colour of her urine and confirmed by the presence of triglycerides and chylomicrons.
At 33 weeks gestation, her proteinuria increased, serum albumin declined and began to experience pre-syncopal symptoms. Her management included dietary modifications and venous thromboembolism prophylaxis was commenced to continue to 6 weeks postpartum. Close fetal monitoring with weekly CTG and fortnightly growth scans were arranged. An MRI of the abdomen/pelvis did not identify any communication between the lymphatic and urinary system. Following recurrent episodes of decreased fetal movements, she was induced at 37+1 weeks and had a successful vaginal delivery with a healthy baby.
Conclusion: The presence of nephrotic-range proteinuria and chyluria together presents unique diagnostic and management considerations. We suspect lymphatic-urinary fistula secondary to increased intra-abdominal pressure but cannot exclude relapsed minimal change disease or a complication of COVID-19. Clinicians should be aware of chyluria as a rare cause for nephrotic-range proteinuria.
Keywords
proteinuria, nephrology, obstetric
References
Onyeije, C. I., Sherer, D. M., & Trampert, J. (1997). Nonfilarial chyluria during pregnancy. Obstetrics & Gynecology, 90(4 Part 2), 699-700.
Svetitsky, S., Lightstone, L., & Wiles, K. (2023). Pregnancy in women with nephrotic-range proteinuria: A retrospective cohort study. Obstetric Medicine, 1753495X231201896.