BACKGROUNDGranulomatosis with polyangiitis (GPA) is an anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis with low prevalence and incidence. Approximately 25% of patients have mild manifestations such as nasal crusts, polyarthralgia, or other nonlife-threatening findings. Involvement of organs such as the lungs, gastrointestinal tract, and central nervous system (CNS) is rare, so alternative diagnoses should be considered. We report a case of a patient with GPA with disease activity in the lungs and liver, initially diagnosed with cancer.
CASE REPORTA 65-year-old white woman was diagnosed in 2018 with localized GPA, ANCA positive, involving mucous membranes (hard palate perforation with oroantral communication), and was in follow-up with Dermatology, using methotrexate 20 mg/week and prednisone 10 mg/day until March 2022, when, due to mucosal signs of activity and weight loss, prednisone was modified to 60 mg/day. One month later, she presented with subacute behavioral changes, mental confusion, psychomotor agitation and persecutory delusions. The patient was hospitalized for investigation. In search of infection, chest tomography showed the presence of multiple solid pulmonary nodules, bilateral, with predominantly peripheral distribution, some minimally cavitated, that did not exist previously; sparse hypovascularized formations were also seen in the liver parenchyma, measuring up to 3 cm, suggestive of neoplastic involvement. CNS was investigated using magnetic resonance imaging, which showed only cavernomas (venous malformations); however, lumbar puncture detected cytomegalovirus infection with a viral load of 12,983 IU/mL, which was confirmed in peripheral blood (4,349,719 IU/mL). Amid treatment with ganciclovir, methotrexate was discontinued and prednisone 60 mg/day was maintained. After two weeks of hospitalization, a lung biopsy was requested, but was not performed because the nodules had disappeared. The liver was biopsied, showing extensive necrotic coagulative areas, associated histiocytic reaction (granulomatous outlines) with epithelioid cells and macrophages, in addition to peripheral inflammation and microthrombosis of the microvascular fiber, confirming disease activity. Methylprednisolone pulse therapy was not prescribed because of the infectious context, and, after treatment, mycophenolate mofetil was initiated considering methotrexate failure and lymphopenia as a contraindication for azathioprine. The patient was discharged with improvement in neurological symptoms, mucosal signs of activity, and inflammatory markers; liver imaging was repeated afterwards.
CONCLUSIONPatients with GPA with nonsevere manifestations are often classified as having nonsevere or limited disease. However, this case report shows that cases initially diagnosed with limited GPA may develop severe organic involvement, requiring a detailed and systematic investigation.
