Sterile abscesses complicating monoclonal gammopathy of undetermined significance.

A 47-year-old man presented with cough, fever and chest pain. A chest CT scan showed multiple nodules with air cavities in some, and IgGj monoclonal gammopathy of undetermined significance (MGUS) was detected. Blood, sputum and bronchoalveolar lavage cultures were negative for common and acid-fast bacteria or fungi. Antineutrophil cytoplasmic antibodies were negative. Empirical broad-spectrum antibiotic therapy was unsuccessful, while steroid therapy (prednisone 50 mg? d) was followed by rapid clinical and radiological improvement. After steroid withdrawal fever recurred and novel pulmonary nodules developed. An open lung biopsy revealed abscesses with acute and chronic inflammatory areas containing neutrophlis and eosinophils, surrounded by giant epitheloid cells and interstitial fibrosis (Fig. 1A). As steroid therapy was resumed, fever disappeared and nodules regressed. The patient remained well on maintenance steroid therapy for 6 months, but shortly after treatment withdrawal fever relapsed and multiple lung, mesenteric, hepatic and splenic abscesses developed (Fig. 1B). As a predominantly eosinophilic abscess was revealed by liver biopsy, visceral larva migrans was suspected and albendazole was given without success. Based on the absence of microorganisms in the lesions, the failure of antimicrobial therapy, and the efficacy of steroid therapy we diagnosed an ‘aseptic abscesses syndrome,’ a rare condition commonly associated with chronic inflammatory bowel disease or MGUS