Rare Manifestation of a Common Disease: Filariasis Presenting as Adult-onset Nephrotic Syndrome

An 18-year-old male, a resident of Eastern Uttar Pradesh, previously healthy, presented with insidious onset oliguria and anasarca over 2 weeks’ period, vitally stable on presentation with a blood pressure of 130/80 mmHg. He was found to have an elevated serum creatinine of 2.4 mg/dl and serum albumin of 1.9 g/dl. Urine examination showed 3+ proteinuria. 24-h urine protein was suggestive of nephrotic range proteinuria (4600 mg/day). Renal ultrasound was suggestive of bilateral kidneys of normal size and echotexture. He was diagnosed with adult-onset nephrotic syndrome. Kidney biopsy revealed a chronic endothelial injury with a membranoproliferative pattern (MPGN) [Figure 1] with occasional glomerular capillary lumen showing elongated parasitic structure with sheathed tails and multiple basophilic nuclei along the length of the tail suggestive of microfilariae [Figure 2]. Glomeruli revealed wrinkled capillaries and retraction of capillary tufts. Glomerular basement membrane remodeling in the form of membrane texture alteration and double contour formation was also noted. Tubular atrophy and interstitial fibrosis involved 10%–15% of the sampled cortex. Mild chronic interstitial inflammation was noted. The immunofluorescence was negative. The patient was started on antifilarial therapy with diethylcarbamazine in a standard dose of 6 mg/kg/day for 12 days, with subsequent remission of proteinuria within 3 weeks. Further follow-up details are not available as he was lost to follow-up.Figure 1: H and E, (×400), glomerulus exhibiting wrinkled/pseudo-thickened capillary basement membranes and double contour formation (Membranoproliferative Glomerulonephritis (MPGN) pattern injury)Figure 2: H and E, (×400), glomerulus showing intracapillary luminal parasitic structure (arrow) with sheathed tail and multiple nucleiFilariasis is a neglected disease, still commonly encountered in the low-socioeconomic status population. India harbors 40% of all cases of filariasis[1] in the world and is trying to reduce the burden actively through various community-based programs.[2] The most common presentation of this infection is asymptomatic microfilaremia, hydrocele, acute adenolymphangitis, or chronic lymphatic disease.[3] Kidney involvement may include microscopic hematuria and/or proteinuria (including nephrotic syndrome) and chyluria.[4] Kidney biopsy findings may include membranous nephropathy, MPGN pattern, or minimal change disease.[5] The treatment includes antifilarial therapy along with antiproteinuric medications.[5] Declaration of patient consent The authors certify that they have obtained all appropriate patient consent forms. In the form, the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed. Financial support and sponsorship Nil. Conflicts of interest There are no conflicts of interest.