Clinical characteristics of anti-GBM disease with thrombotic microangiopathy: a case report and literature review

The coexistence of anti-glomerular basement membrane (anti-GBM) disease with thrombotic microangiopathy (TMA) is rarely encountered, and the clinical characteristics of this phenomenon are not well known. A 76-year-old Japanese woman with a history of idiopathic pulmonary disease was diagnosed with anti-GBM disease due to rapidly progressive glomerulonephritis and a positive anti-GBM antibody test result. We treated the patient with hemodialysis, glucocorticoids, and plasmapheresis. During treatment, the patient suddenly became comatose. TMA was then diagnosed because of thrombocytopenia and microangiopathic hemolytic anemia. The activity of a disintegrin-like and metalloproteinase with thrombospondin type 1 motif 13 (ADAMTS-13) was retained at 48%. Although we continued the treatment, the patient died of respiratory failure. An autopsy revealed the cause of respiratory failure to be an acute exacerbation of interstitial pneumonia. The clinical findings of the renal specimen indicated anti-GBM disease; however, there were no lesions suggestive of TMA. A genetic test did not reveal an apparent genetic mutation of the atypical hemolytic uremic syndrome. We conducted a literature review of past case reports of anti-GBM disease with TMA. The following clinical characteristics were obtained. First, 75% of the cases were reported in Asia. Second, TMA tended to appear during the treatment course for anti-GBM disease and usually resolved within 12 weeks. Third, ADAMTS-13 activity was retained above 10% in 90% of the cases. Fourth, central nervous system manifestations occurred in more than half of the patients. Fifth, the renal outcome was very poor. Further studies are required to understand the pathophysiology of this phenomenon.