An unusual cause of gross hematuria and renal dysfunction in a young male
A 31-year-old male presented with 1 week history of anorexia, headache, and gross hematuria. He did not have history of fever, urinary tract infection, stone disease, rash, arthralgia, night sweats, and weight loss, nor was there any significant past history. He was a non-smoker and non-alcoholic, and family history was not contributory. On examination, his blood pressure was 180/100 mmHg, heart rate was 100/min and he had mild pallor. Systemic examination was normal and fundus examination did not reveal any changes of hypertensive retinopathy.\nInvestigations revealed normal hemoglobin (11.5 g/l), total leukocyte count (9500/dl) and platelet count (2.4 × 106/dl), but increased serum creatinine (4.8 mg/dl). Urine examination revealed proteinuria (4+) and dysmorphic RBCs (>80% of RBCs), and his 24-h urine protein excretion was 3.8 g. For evaluation of gross hematuria, he underwent cystoscopic examination, ultrasonography and non-contrast computerized tomography of the genitourinary tract, which were normal. Anti-nuclear antibodies, anti-neutrophil cytoplasmic antibodies, anti-glomerular basement membrane antibodies and serum cryoglobulins were negative, so were hepatitis B surface antigen, anti-hepatitis C antibody and human immunodeficiency virus. His renal function further deteriorated, requiring initiation of hemodialysis, and subsequently, a kidney biopsy was performed. The kidney biopsy specimen contained nine glomeruli, and consisted of both cortex and medulla. Light microscopy examination of the biopsy revealed that all the glomeruli showed mesangial expansion, hypercellularity and mesangial nodules. Cellular crescents were present in two glomeruli along with focal glomerular basement membrane thickening. The tubulointerstitial compartment showed fibrosis and atrophy involving <30% of the biopsy area, while the blood vessels were normal []. The mesangial nodules were periodic acid-schiff (PAS) positive but Congo red negative. Immunofluorescence examination revealed 2+ to 3+ diffuse linear staining for kappa light chains in mesangium and tubular basement membrane []. Electron microscopy examination showed powdery electron-dense material in the lamina rara interna of the glomerular basement membrane as well as on the outer aspect of the tubular basement membrane [ and ]. With these findings, a diagnosis of LCDD was made and he was investigated further.\nSerum electrophoresis was performed, which revealed a monoclonal band in the gamma region that, on immunofixation, was confined to the kappa and IgG regions. Serum kappa free light chain level was elevated and bone marrow examination revealed 8% plasma cells. Thus, the LCDD was thought to be non-myeloma related. He was started on bortezomib, thalidomide and dexamethasone regimen. After four cycles, his hematuria settled; however, renal functions did not improve. Repeat serum immunofixation was negative. He was initiated on maintenance hemodialysis on which he is doing well since the last 3.5 years and is planned for deceased donor renal transplantation.