S GLEESON1, A SALMON2
1Middlemore Hospital, Auckland, New Zealand; 2Waitemata District Health Board, Auckland, New Zealand
Background: Methamphetamine use is increasing worldwide and clinicians should be aware of its multitude of adverse effects. Our case describes a previously unrecognised form of methamphetamine-related kidney disease.
Case Report: A 22 year-old caucasian man presented with left hand trauma; high creatinine was incidentally noted. He reported ankle oedema, frothy urine and chronic (but exclusive) methamphetamine use. He was hypertensive (150/90mmHg) and oedematous. Investigations showed creatinine 247umol/L (60-105), calcium 2.00mmol/L (2.10–2.55), haemoglobin 116g/L (130–175), low complement (C3 0.8g/L [0.8–1.8], C4 0.1g/L [0.2–0.6]), active urine sediment (210 erythrocytes/hpf) and nephrotic-range proteinuria (protein-creatinine ratio 644mg/mmol). Autoimmune, vasculitic, metabolic, toxicology and infective screens were negative. Renal biopsy showed an immune complex glomerulonephritis with intense interstitial nephritis: the glomerular abnormality did not correspond to any recognisable form of immune complex glomerulonephritis. Despite methamphetamine cessation and a therapeutic trial of oral prednisone 0.5mg/kg/day, proteinuria failed to improve and eGFR continues to decline.
Conclusions: Methamphetamine use is growing worldwide. Renal adverse effects of methamphetamine include rhabdomyolysis, acute tubular necrosis and acute renal failure from acute intoxication, and an accelerated decline in renal function with chronic use. Renal outcomes vary, from spontaneous recovery after stopping methamphetamine use to end-stage renal failure in over half of patients.
A recent renal biopsy series of methamphetamine users demonstrated high rates of hypertension and chronic kidney disease. Of those that underwent biopsy, half showed a mesangiocapillary glomerulonephritis type 1, with IgM/C3 deposition. Other biopsies demonstrated necrotising vasculopathy and pseudovasculitis. This represents a novel methamphetamine-related immune complex glomerulonephritis coupled with intense interstitial inflammation.