72-year-old man with fever, skin lesions, and consolidation on chest radiograph.

A 72-year old man was admitted to the hospital with a fever as high as 39°C; mild dyspnea; and tender, erythematous, vesicular skin lesions on his lower legs, forearms, and neck (Fig 1). A chest radiograph showed patchy consolidation in the right upper, right lower, and left lower lobes. Medical history was remarkable for a 1-year history of myelodysplastic syndrome. On admission, his hemoglobin level was 8.5 g/dL, and WBC count was 6 3 10/L, with a differential of 52% segmented neutrophils, 20% lymphocytes, 26% monocytes, and 2% eosinophils. The platelet count was 80 3 10/L. Appropriate blood, sputum, urine, and skin cultures were obtained, and the patient was empirically started on IV ampicillin. Over the next 36 h, the skin lesions and dyspnea worsened. Culture results were negative. A skin biopsy revealed a sterile, diffuse, nodular infiltration of the dermis by mature neutrophils. BAL revealed a WBC count of 11.2 3 10/L, with a differential of 90% neutrophils, 3% eosinophils, and 7% macrophages. No pathogenic organisms or malignants cells were found. Transbronchial biopsy revealed interstitial infiltration by large numbers of neutrophils with occasional eosinophils and small numbers of lymphocytes. There was no evidence of granulomatous inflammation. At this point, which of the following is the correct treatment?