Mesangial proliferative glomerulonephritis with acute tubule interstitial nephritis leading to acute kidney injury in influenza A (H1N1) infection
A 52-year-old female patient was admitted in March 2012 with fever, cough, breathlessness and progressive dyspnea with respiratory distress and decrease urine output of 10 days duration. There was no history of abdominal pain, dysuria or trauma and no recent use of non-steroidal anti-inflammatory medication.\nOn examination, she was breathless with blood pressure of 150/90 mmHg, temperature 40°C, respiratory rate of 30 breaths/min, heart rate of 100 bpm. Laboratory investigations revealed hemoglobin, 10.3 g/l; total white cell count, 9.88 × 103/μl (differential count: 74% neutrophils, 20% lymphocytes, 4% monocytes and 2% eosinophils); platelet count, 211 × 103/μl; serum creatinine (SCr), 10.8 mg/dl sodium, 138 mEq/l; potassium, 5.3 mEq/l; blood urea, 76 mg/dl; and blood glucose, 72 mg/dl.\nRenal ultrasound showed normal sized kidneys with hyper reflective cortex. Serological tests for malaria, leptospirosis, dengue and viral hepatitis were negative. The initial blood, urine and sputum cultures were sterile. Urinalysis showed proteinuria, hematuria and two to five fine granular casts. SCr phosphokinase levels and liver function test chest radiograph were unremarkable while tests for antinuclear antibody, anti-double-stranded deoxyribonucleic acid, anti-neutrophil cytoplasmic antibody, anti-glomerular basement membrane antibody, coombs’ test, cryoglobulins and C-reactive protein were all negative and complement components (C3 and C4) were low. Enzyme-linked immunosorbent assays test for human immunodeficiency virus (HIV), hepatitis B surface antigen and hepatitis C virus were negative. Patients had influenza H1N1 virus subtype specific ribonucleic acid detected in a nasopharyngeal swab using reverse transcriptase-polymerase chain reaction. She had a history of exposure to swine flu positive patient and was managed using oseltamivir, antibiotic, fluid replacement and dialysis. Patients received oseltamivir, 75 mg within 48 h of presumed diagnosis for 5 days and supportive measures as needed. Initially, she was treated with peritoneal dialysis and she remained oliguric and required intermittent hemodialysis for a total of 5 times through temporary jugular dialysis catheter for 4 h each.\nRenal biopsy [] revealed two fragment of renal tissue containing 11 glomeruli with associated tubules and vessels. All the glomeruli show uniform mesangial prominence. Capillary lumina were open, and membranes were of normal thickness. Tubules showed mild to moderate degeneration. Interstitium was mildly prominent for uniform edema and diffuse infiltration with leucocytes. Immunofluorescence microscopy did not reveal staining with anti-human sera tested (IgG, IgM, IgA and C1q). Influenza nucleoprotein (InfA-NP) antigen-positive cells were not detected in kidney tissue. A diagnosis of mesangial proliferative glomerulonephritis with acute tubule interstitial nephritis was made. The patient was treated with methyl prednisolone 500 mg for 3 days followed by oral prednisolone 1 mg/kg/day. Her condition also improved rapidly and she was discharged with SCr of 1.5 mg/dl. Her SCr was 1 mg/dl at 1 month follow-up.