MON-030 AUTO-IMMUNE PHENOMENA IN TREATED HIV - A RARE CASE OF ANCA VASCULITIS

Abstract

Anti-neutrophil cytoplasmic antibody (ANCA) positivity has been reported in up to 8% of people living with the human immune-deficiency virus (HIV) (PLHIV). Despite the prevalence of serologic ANCA positivity, it is rarely associated with vasculitis and organ-specific disease in this population. Here we present a rare case of ANCA positivity with a clinical syndrome of rapidly progressive glomerulonephritis (RPGN) and histology proven pauci-immune necrotizing glomerulonephritis (GN). Here we present a rare case of ANCA-associated vasculitis and RPGN in a patient with longstanding, treated HIV. A 69-year-old male presented to a local teaching hospital with 4 weeks of dry cough, dyspnoea and coryzal symptoms. HIV infection had been diagnosed 11 years prior. His most recent bloods showed a normal CD4 count and a sustained undetectable viral load on long-term highly active anti-retroviral therapy (HAART). In February 2017 his creatinine was 86umol/L. At presentation in March 2018, his CD4 count was 0.14 x 10^9/L (0.56 - 1.58) with an undetectable viral load. He was hypoxic with bilateral crackles and had a creatinine of 441umol/L, pANCA + with MPO titre >740 CU (<20) and diffuse bilateral infiltrates on CXR consistent with pulmonary haemorrhage. Renal ultrasound showed normal sized kidneys with no evidence of obstruction or chronic kidney disease. Renal biopsy confirmed pauci-immune necrotizing GN with 10% cellular crescents and no evidence of chronic renal disease. Immunofluorescence demonstrated focal mesangial positivity for C3 in the glomeruli. The diagnosis of MPO-ANCA-associated microscopic polyangiitis was made. The patient was treated with haemodialysis, plasma exchange, steroids and cyclophosphamide with azathioprine maintenance. After 3 months, he showed evidence of renal recovery and ceased dialysis. His creatinine at 7 months was 218umol/L with MPO-ANCA titre in the normal range. Disease remission was demonstrated with standard immuno-suppressive therapy and at 7 months follow-up he remained free from infective complications and had not compromised control of his HIV. Other authors have described auto-immune disease (AD) occurring in PLHIV and have successfully treated these patients with standard immuno-suppressive therapy. Yen et al. (2017) found PLHIV being treated with HAART demonstrated an increased risk of psoriasis, auto-immune haemolytic anaemia and uveitis. Evans et al. (2014) reported a case of ANCA-associated vasculitis and pauci-immune GN in HIV which responded to immuno-suppressive therapy without infective complications or flare of HIV. ANCA associated vasculitis and RPGN presentations are rare in PLHIV. Improved therapies and follow-up for PLHIV may contribute to increasing numbers of patients living with well-controlled HIV who remain at risk of AD in the setting of chronic immune dysregulation.