Abstract
Background: It is estimated that around 120 million people in tropical and subtropical areas of the world are infected by filariasis. In the Southeast and South Asian regions, Wuchereria bancrofti is the most prevalent parasite,causing filariasis in 99.4% of cases. We report a rare case of amyloidosis kidney with an incidental finding of microfilariae.
Case report: An 85 year old male presented with complaints of gradually progressive anasarca and loss of weight for 2 months as well as vomiting and decreased urine output for a week. On clinical examination, aside from mild pallor, there was evidence of bilateral pitting pedal edema and free fluid in the abdomen. Sonography revealed the presence of bilateral renal parenchymal disease and bilateral hydrocele with thickened spermatic cord. Lower lobe consolidation was the only significant finding on the chest skiagram. The patient was rigorously worked up to identify pathology in other systems, but all the data were within normal limits. Histopathological examination of the renal biopsy specimen revealed complete to partial replacement of most of the glomeruli by pink, hyaline eosinophilic material and microfilariae of Wuchereria bancrofti were seen incidentally. Blood vessels showed pink hyaline material in their walls. Tubules and interstitium were unremarkable. The provisional diagnosis of amyloidosis kidney was confirmed by positivity on methyl violet staining.
Conclusion: In the present case, the clinical picture did not provide any clue regarding the association of amyloidosis kidney with filariasis except for mild peripheral eosinophilia. However, renal biopsy revealed amyloidosis with microfilariae of Wuchereria Bancrofti. It is presumed that, in this case, microfilariae entered the glomerular capillaries after breaching the blood renal barrier. This is the first case in which renal amyloidosis was shown to be associated with microfilariae of Wuchereria bancrofti. The possibility of the latter condition, resulting in the genesis or development of the former, needs to be further investigated and discussed.
