Dr Ben Tomlinson, Dr Vino Kavarthapol Jayaraman
1Fiona Stanley Hospital, Perth, Australia
Biography:
bio to come
Background:
IgA nephropathy (IgAN) is the most common primary glomerulonephritis. Secondary causes of IgAN include inflammatory, infectious, malignant, and autoimmune disorders and their treatments. Deposition of galactose-deficient IgA1 with complement activation and immune complex deposition is seen in primary and secondary IgAN. It is unclear whether this is a manifestation of a common triggering pathway or different processes leading to similar pathologic lesions. Ustekinumab is an interleukin (IL)-12/IL-23 blocking monoclonal antibody used in management of psoriasis infrequently associated with IgAN. We describe the first case of Ustekinumab induced IgAN in Australia.
Case Report:
A 57yo man was referred for evaluation of declining renal function following initiation of Ustekinumab 18months earlier for psoriasis. He had psoriasis for 24 years, previously inadequately controlled but improved with Ustekinumab 90mg subcutaneously 3 monthly. Other past medical history included hypertension of 6 years duration on olmesartan 20mg daily, and obesity (BMI 31.4). Baseline renal function was normal but following initiation of Ustekinumab showed progressive deterioration with a creatinine peak of 143mmol/L and new haemoproteinuria (urine Albumin/Creatinine ratio 128.1). He remained asymptomatic. Serum ANA was positive (15IU/mL) in a homogenous nucleolar pattern, other autoimmune markers and viral serologies were negative. Renal biopsy showed glomerulomegaly with mild mesangial hypercellularity and deposits. Immunofluorescence demonstrated glomerular mesangial deposits of IgA and C3c in keeping with a diagnosis of IgAN.
Conclusions:
This case represents the first reported case of Ustekinumab induced IgAN in Australia. Whilst rare, it is an important adverse effect to acknowledge as treatment prevents long-term renal consequences of progressive IgAN. Treatment involves Ustekinumab cessation, consideration of short course steroid therapy, and exploration of alternative management options for psoriasis.