Multiple Intramuscular Abscesses Caused by <i>Nocardia abscessus</i> in a Patient with Chronic Obstructive Lung Disease: Clinical Microbiology Considerations

Nocardiosis is uncommon. Immunocompromising conditions predispose individuals to pulmonary and disseminated nocardiosis of the brain, skin, and subcutaneous tissues. The most common pathogens are <i>Nocardia cyriacigeorgica</i>, <i>Nocardia nova</i>, and <i>Nocardia farcinica</i>. The speciation of <i>Nocardia</i> to determine antimicrobial susceptibility is difficult using traditional biochemical methods. Here, we report the case of a 73-year-old man with chronic obstructive lung disease who developed a rapidly progressing intramuscular abscess around the left hip and thigh. Within 3 days, the lesions progressed to an epidural abscess at the L4 to S1 level. Although he was treated with broad-spectrum antibiotics and extensive incision and drainage, he died of rapidly progressive respiratory failure. <i>Nocardia abscessus</i> (<i>N. abscessus</i>) was identified in pus samples using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). This case shows that the diagnosis of an intramuscular abscess caused by <i>N. abscessus</i> is challenging and that using MALDI-TOF MS may facilitate the diagnosis and ensure appropriate treatment.