#6949 MPO ANCA-ASSOCIATED VASCULITIS IN A PATIENT WITH A HISTORY OF METHAMPHETAMINE ABUSE

Abstract

Abstract Background and Aims Methamphetamines cause kidney damage by different mechanisms. The most common is the tubular lesion associated with myoglobinuria secondary to rhabdomyolysis. Other renal effects include prerenal azotemia, acute tubular necrosis, malignant hypertension, and necrotizing vasculitis have been reported. It is important to consider this drug as a possible cause of glomerulonephritis. Method We present the case report of a patient with suspected MPO ANCA-associated vasculitis from methamphetamines. Results A 24-year-old male, he was admitted to nephrology due to hematuria and proteinuria accompanied by serum creatinine elevation (2.5 mg/dl). He reported inhaled methamphetamine abuse since the age of 14, smoking and occasional ethylism. His symptoms began in October 2022 with asthenia and adinamia, accompanied by generalized pallor and edema in both malleoli. At admission with normal blood pressure (112/70 mmHg). Laboratory tests revealed: leukocytes 6.35 thousand/UL, hemoglobin 7.7 g/dl, platelets 698,000 thousand/UL, urea 70.81 mg/dl, sodium 137 mmol/L, potassium 4.72 mmol/L, albumin 3.85 g/dl, urine test with proteinuria 25 mg/dl, hemoglobinuria 250 eri/microL, leukocytes 15-20 field and countless erythrocytes, albuminuria 450.87 mg/day, globular sedimentation rate 18 mm/hr, reactive protein C 37 mg/L. Complement levels were normal, negative serologies for hepatitis B, C, human immunodeficiency viruses, antinuclear antibodies, double-stranded anti DNA and anti-proteinase 3, but was positive for IgG anti myeloperoxidase (anti-MPO) 33.6 U/ml. Urinary sediment showed the presence of dysmorphic erythrocytes, as well as abundant erythrocyte and granular casts. Ultrasound-guided renal biopsy was performed; light microscopy reported 21 glomeruli, 6 globally sclerosed, 4 with irregular segmental sclerosis, 4 with destruction and granuloma formation. Immunofluorescence showed traces of mesangial IgM, the rest negative for IgG, IgA, C3, C1q, fibrinogen, kappa and lambda. The patient received 3 pulses of methylprednisolone 500 mg followed by oral prednisone and rituximab. Baseline creatinine decreased to 1.88 mg/dl. Conclusion Inhaled methamphetamine is commonly used in young people, it is important to consider this drug as a possible cause of crescentic and necrotizing glomerulonephritis.