PT - JOURNAL ARTICLE AU - Qurratulain Qurratulain AU - Azeem Ahmed AU - Quentin Jones TI - Lesson of the month: Severe granulomatosis with polyangiitis (GPA): a diagnostic challenge during the COVID-19 pandemic AID - 10.7861/clinmed.2020-0793 DP - 2021 Jan 01 TA - Clinical Medicine PG - 79--80 VI - 21 IP - 1 4099 - http://www.rcpjournals.org/content/21/1/79.short 4100 - http://www.rcpjournals.org/content/21/1/79.full SO - Clin Med2021 Jan 01; 21 AB - We present the case of a 71-year-old woman with bilateral pneumonia who continued to deteriorate despite multiple courses of antibiotics. When dexamethasone was added to cover the possibility of COVID-19 pneumonia, she rapidly improved. Subsequently, she was found to have a strongly positive PR3 anti-nuclear cytoplasmic antibody (ANCA) and clinical features consistent with granulomatosis with polyangiitis (GPA) with upper respiratory tract and renal involvement. The case highlights how the COVID-19 pandemic can create new challenges in the diagnosis of GPA.