Diagnosis and management of pulmonary infection due to Rhodococcus equi.

BACKGROUND: Rhodococcus equi is a recognized cause of disease in humans, especially in individuals who are immunocompromised. Because diphtheroids are regarded as part of normal respiratory flora, the importance of R. equi as a pulmonary pathogen may not be fully appreciated and its prevalence may be underestimated. Most treatment recommendations for R. equi infection were established before antiretroviral drugs became available for human immunodeficiency virus/AIDS therapy, and therapeutic strategies may need to be updated. OBJECTIVES: To review the role of R. equi as a cause of pulmonary infection; to highlight its importance for clinicians and microbiologists; and to challenge current approaches to treatment, whether in immunodeficient or immunocompetent individuals. SOURCES: A PubMed search using combinations of the following terms: 'Rhodococcus (automatically including Corynebacterium) equi' AND 'pneumonia' OR 'pulmonary' infection, then cross-checking references in the resulting cases, case series and reviews. CONTENT: We provide a review that details the challenges in the diagnosis, microbiology and pathogenesis of pulmonary infection caused by R. equi and the options for treatment. IMPLICATIONS: Ten to 14 days of treatment may be effective for pneumonia due to R. equi. Our review suggests that longer courses of therapy are needed for cavitary lesions and lung masses. However, recommendations for excessively prolonged treatment of all pulmonary infections arose during a time when many cases occurred in individuals with AIDS and before effective antiretroviral therapy was available. We suggest that the rationale for prolonged therapy with multiple antibiotics needs to be re-evaluated.

Scleritis, keratitis, and orbital cellulitis: isolated ocular manifestation of systemic lupus erythematosus.

Systemic autoimmune diseases are associated with ocular inflammatory conditions such as episcleritis, scleritis, keratitis, and uveitis. However, ocular manifestations have been reported to correlate with the extent of systemic disease. We present a patient with scleritis, keratitis, and orbital cellulitis, as the isolated manifestation of systemic lupus erythematosus (SLE). No microbial etiology was identified and antibiotics did not produce clinical improvement. The patient improved significantly with steroids and disease-modifying antirheumatic drugs. Although ocular inflammation has been previously remarked in SLE of systemic severity, in this case there were no other organs with SLE involvement. We briefly discuss the ocular manifestations of SLE, which can involve all segments of the eye, including cornea, sclera, retina, uvea, optic nerve, and orbit.