A man with skin rash and respiratory failure

Abstract

A 51-year-old man, a non-smoker and non-drinker, with history of pulmonary tuberculosis (TB), hypertension, hyperlipidemia and gout, was admitted for rash over his bilateral lower limbs for a few days (Figure 1). The rash was neither itchy nor tender. His complete blood picture including eosinophilic count, renal and function tests were grossly normal, but both ESR and CRP were elevated with 63mm/h (<20mm/h) and 30.9mg/L (<=8.2mg/L) respectively. Anti-nuclear Antibody (ANA) was negative and C3 and C4 level were normal. Anti-myeloperoxidase anti-neutrophilic cytoplasmic antibody (Anti-MPO ANCA) was positive with a level of 53 unit (<= 20 units). Urine protein creatinine ratio was 29 (<= 11mg/mmol Cr) and there was no dysmorphic red blood cell detected. His Chest X-ray (CXR) was completely clear. Skin biopsy showed that the small vessels were infiltrated by neutrophils with fibrinoid necrosis, nuclear dusts and extravasated red blood cells. Scanty eosinophils were also seen. The larger vessels were not involved. Immunofluorescence studies with IgA, IgG, IgM, C3 and fibrinogen were all negative with no deposits in the vessels wall. The overall feature was compatible with leukocytoclastic vasculitis. A low dose of oral prednisolone 15 mg daily was started for the cutaneous small vessel vasculitis. However, he had mild bloodstained sputum 3 days later. He was given Augmentin and intravenous hydrocortisone empirically. His serial CXR remained clear (Figure 2). However, he developed respiratory failure 3 days later and his new CXR reviewed extensive infiltrates bilaterally (Figure 3). He was intubated and transferred to the intensive care unit. Urgent computed tomography (CT) scan of the thorax showed diffuse airspace consolidations in both the lungs with batwings distribution (Figure 4). His hemoglobin level was dropped from 10.6 to 7.5 g/dL (13.5-17.3g/dL) at that time.