T SOE1, S CHERIAN1,2, B PAWAR1, D FERNANDES1, S NAYAR1, P GEORGE1, S THOMAS1
1Department of Nephrology, Alice Springs Hospital, Alice Springs, Australia, 2Department of Nephrology, Royal Darwin Hospital, Darwin, Australia
Background: It has been known that there is an association between renal glomerular diseases and autoimmune thyroiditis. However, the coexistence of antineutrophil cytoplasmic antibody (ANCA)-associated glomerulonephritis and membranous nephropathy (MN) in such patients is rare.
Case report: A 61-year-old Caucasian man presented with microscopic haematuria and new onset renal impairment, which was preceded by a flu like illness. His past medical history included Hashimoto’s thyroiditis, renal calculi, hypertension and obesity. At presentation, his serum creatinine was 151 micromol/L and urine albumin creatinine ratio (ACR) was 200 mg/mmol. Serum ANCA was positive and myeloperoxidase titre was >80 AI (ref: <1 AI). Other glomerulonephritis serology including anti-glomerular basement membrane antibody and anti-dsDNA were negative. Thyroid stimulating hormone was 13.9 mU/L, with anti-thyroperoxidase antibody of 225 IU/mL and antithyroglobulin of 660kU/L. Renal biopsy showed focal segmental necrotising crescentic lesions in 36% of the glomeruli with minimal scarring in 10% of the interstitium. Immunofluorescence was strongly positive for granular pattern distribution of IgG. There were epimembranous deposits correlating with stage 1 membranous nephropathy in electron microscopy. Circulating anti-phospholipase A2 receptor (PLA2R) antibody and PLA2R staining on renal biopsy were negative. Malignancy as a secondary cause of MN was excluded by negative CT chest, abdomen and gastrointestinal endoscopy. He received induction therapy with methylprednisolone for 3 days followed by oral prednisolone and Rituximab 375mg/m2 weekly for 4 weeks. At the end of five months, his serum creatinine was 136 micromol/L. Urinalysis showed no haematuria and urine ACR was 56.4 mg/mmol.
Conclusion: To our knowledge, this is the first reported case of ANCA vasculitis with MN associated with Hashimoto’s thyroiditis, which was successfully treated with combination of steroid and Rituximab therapy.
Thwe is a nephrology advanced trainee currently working at Fiona Stanley Hospital. This presentation is for the case which she encountered during her time at Alice Springs Hospital. She has the interest in autoimmune related glomerulonephritis.