[Pulmonary malacoplakia caused by Rhodococcus equi in AIDS: a case report]

We describe the observation of a right upper lobe consolidation with cavitation produced by Rhodococcus equi in a patient suffering from AIDS. The inefficacy of a prolonged antimicrobial therapy adapted against R. equi led to a right upper lobectomy. The histopathology showed a pseudotumoral mass, with dense infiltration of macrophages containing Michaelis-Gutmann bodies, which was positive for the culture of R. equi. Pulmonary malacoplakia with Rhodococcus equi was diagnosed. This pathology should be evoked when a R. equi pneumonia persists despite a right management of treatment for several months. The features of pneumonia with Rhodococcus equi and of pulmonary malacoplakia are taken from a literature review.