Development of microscopic polyangiitis following idiopathic pleuroparenchymal l fibroelastosis: A case report.

Idiopathic pleuroparenchymal fibroelastosis (PPFE) is a rare type of idiopathic interstitial pneumonia, which is characterised by pleural fibrosis and subjacent parenchymal fibroelastosis of the upper lobes. Herein, we present a case of microscopic polyangiitis (MPA) following PPFE. The patient had abnormal shadows on chest radiographs 15 years before the onset of MPA, and the patient was diagnosed with PPFE. Four years after the PPFE diagnosis, the patient was diagnosed with MPA based on persistent fever, purpura, mononeuritis multiplex, myeloperoxidase-antineutrophil cytoplasmic antibody positivity, and pathological findings of peritubular capillaritis on kidney biopsy. The patient was treated with glucocorticoids, including methylprednisolone pulse therapy and rituximab, followed by maintenance therapy with rituximab. One year after treatment, the PPFE had not worsened. PPFE occasionally occurs secondary to connective tissue disease, including MPA; however, to the best of our knowledge, this is the first report of PPFE preceding MPA. Our case suggests that PPFE, as other interstitial lung diseases, may be associated with MPA and precede the onset of MPA. The accumulation of more cases is needed to clarify the characteristics of MPA-associated PPFE.

A case of systemic lupus erythematosus having concurrent Evans syndrome and acquired thrombotic thrombocytopenic purpura.

An 18-year-old Japanese woman with systemic lupus erythematosus experienced dyspnoea, headache, tinnitus, and purpura for 2 weeks and was admitted to our hospital. The patient had been diagnosed with systemic lupus erythematosus and secondary immune thrombocytopenia 8 years before and treated with high-dose prednisolone and mycophenolate mofetil. Since the blood test on admission showed haemolytic anaemia with a positive direct Coombs test and anti-glycoprotein IIb/IIIa antibodies, the patient was initially diagnosed with Evans syndrome (ES). The patient was treated with pulse intravenous methylprednisolone followed by 45 mg/day prednisolone; however, the patient's platelet count did not normalise. Based on a low level of a disintegrin-like and metalloproteinase with thrombospondin type 1 motif 13 (ADAMTS-13) activity and a high level of ADAMTS-13 inhibitors, a diagnosis of acquired thrombotic thrombocytopenic purpura (TTP) was confirmed. After undergoing therapeutic plasma exchange for 6 consecutive days, the patient's platelet count recovered rapidly. Although concurrent acquired TTP and ES have not been reported previously, the findings from this case highlight the importance of measuring ADAMTS-13 activity and inhibitors to rule out acquired TTP, especially when ES is refractory to glucocorticoids.