Probable leprosy-associated systemic AA amyloidosis presenting as end-stage kidney disease in an adolescent: diagnostic and therapeutic challenges in a resource-limited endemic setting

AA amyloidosis is a systemic complication of chronic inflammatory and infectious diseases. Although renal involvement is a major determinant of prognosis, leprosy-associated renal amyloidosis is now rarely reported in contemporary nephrology literature. We report an 18-year-old male with relapsed multibacillary Hansen disease, suspected erythema nodosum leprosum, and previous treatment interruption who developed massive proteinuria, severe hypoalbuminemia, progressive kidney dysfunction, and end-stage kidney disease requiring chronic hemodialysis. The patient had also been treated for presumed intestinal tuberculosis during evaluation for chronic diarrhea; however, subsequent gastrointestinal biopsies demonstrated amyloid deposition involving the esophagus, stomach, duodenum, ileum, and colon, suggesting that gastrointestinal symptoms may have been partly or predominantly attributable to systemic amyloidosis. Kidney biopsy showed extensive amorphous extracellular deposits involving renal tissue, with Congo red positivity, consistent with renal amyloidosis. Immunofluorescence showed moderate IgM staining only, without specific IgG, IgA, C3, or C1q deposits. The combined renal and gastrointestinal findings established Congo red-positive systemic amyloidosis clinically most consistent with probable leprosy-associated AA amyloidosis. Serum amyloid A immunohistochemistry, mass spectrometry-based amyloid typing, serum amyloid A measurement, and serial inflammatory marker monitoring were not available; therefore, AA amyloidosis could not be pathologically confirmed and normalization of inflammatory activity after treatment could not be assessed. This case highlights a preventable but severe pathway from uncontrolled chronic infectious inflammation to kidney failure and illustrates diagnostic and therapeutic constraints in resource-limited endemic settings.