A case of an acute onset IgA nephropathy presenting with macroscopic hematuria and nephrotic syndrome: Clinicopathological view

Abstract

  IgA nephropathy is characterized by prominent and diffuse IgA deposits in the glomerular mesangium on immunofluorescent microscopy. Clinical manifestation of IgA nephropathy varies and ranges from asymptomatic urinary abnormalities to acute renal failure. Most of the patients show microscopic hematuria and/or asymptomatic proteinuria and some of the patients present with an acute nephritic syndrome and/or nephrotic syndrome.
  We describe a 5-year-old girl with an acute onset IgA nephropathy with nephrotic syndrome and macrohematuria. She was initially treated with steroid, anticoagulant and thrombolytic agents and her proteinuria was decreased. However. her proteinuria was not decreased to less than 1.0 g/day. Then she was additionally treated with angiotensin converting enzyme inhibitor (ACEI) and her proteinuria was completely disappeared in 4 months. The renal specimens obtained at her acute phase revealed thin and irregular segments of the glomerular basement membrane (glomerular membranolysis), and IgA deposits in the mesangial region and in the glomerular capillary wall. Repeat biopsy after 1 year remission showed an improvement of those pathological changes. Administration of ACEI is considered to induce alteration in glomerular circulatory dynamics leading to improve the damage of size selectivity and charged barrier of the basement membrane. Most of the patients with an acute onset IgA nephropathy have favourable prognosis, however a part of the patients have poor prognosis and its characteristic pathologic feature of membaranolysis is one of the indicators of poor outcome in IgA nephropathy. Considering a pathognomonic change in IgA nephropathy and the pharmacological effects of ACEI, ACEI therapy would be recommended to prevent and/or improve the basement membrane damage in the patients with an acute onset IgA nephropathy.