Granulomatous Disorder With Pulmonary and Renal Involvement: A Diagnostic and Therapeutic Dilemma

Abstract

Granulomatosis with polyangiitis (GPA) can present with a wide array of clinical signs and symptoms; therefore, it should be differentiated from other mimicking clinicopathological entities. We report a case of a 66-year-old gentleman who was found to have a mediastinal mass and histopathological examination showed chronic necrotizing granulomatous inflammation. The patient was managed on lines of pulmonary tuberculosis for 12 months and remained in remission for two years. Later, workup showed cytoplasmic antineutrophil cytoplasmic antibodies (c-ANCA)-associated granuloma with marked renal impairment, which responded to immunosuppression. From this, we suggest that in a patient with radiological evidence of mediastinal mass, the remote possibility of GPA must be kept in mind.

Keywords: anca vasculitis; anti-tuberculous therapy; granulomatosis with polyangiitis; mycophenolate mofetil; tuberculosis.

Figure 1. Hematoxylin and eosin-stained light microscopic images.

A (x10); B and C (x40). Non-caseating granuloma (red arrow), necrosis (orange arrow), and epithelioid histiocytes (blue arrow).

Figure 2. Chest X-ray images.

A: Round ill-defined opacity in the mediastinum (red arrow) and reduced opacity size post-anti-tuberculous therapy initiation (green arrow). B: Recurrence of mediastinal opacity two years later (red arrow) and resolution of opacity post-mycophenolate mofetil (MMF) initiation (green arrow). C: Resolved opacity immediately post-MMF initiation (green arrow) and sustained resolution till now (green arrow).