Rhodococcus equi pneumonia in a renal transplant patient: a case report and review of literature

Abstract

Immunocompromised patients are susceptible to many pathogens, including those that are predominantly problems in veterinary medicine. We report a case of a 42-yr-old white male who presented 19 months post-cadaveric renal transplant (for IgA nephropathy) with a 5 d history of nausea, vomiting, abdominal cramping and diarrhea. Admission chest X-ray revealed a suspicious mass lesion in the left lower lobe. Computed tomography (CT) guided biopsy of the lesion showed a large zone of CD68 +ve histiocytes in a non-caseating granuloma. Gram stain revealed multiple gram-positive rods within the histiocytes, which were eventually identified as R. equi. After 4 months of therapy with fluoroquinolones (Avelox) and Azithromycin a repeat CT showed complete resolution of the lesion. We reviewed the literature with special focus on the clinical features, challenges in diagnosis, and treatment of this rare infection (especially in the transplant patients who are also on immunosuppressive therapy).

Internally Controlled Real-Time PCR Method for Quantitative Species-Specific Detection and vapA Genotyping of Rhodococcus equi

“…In recent years R. equi has emerged as an opportunistic human pathogen, especially in individuals infected with human immunodeficiency virus. In the human host the infection presents usually as tuberculosis-like cavitary pneumonia or bacteremia (2,36). R. equi is also being increasingly reported in other animal species, mainly associated with extrapulmonary, purulent, caseating infections (5,33).…”

Daptomycin Susceptibility of Unusual Gram-Positive Bacteria: Comparison of Results Obtained by the Etest and the Broth Microdilution Method

“…However, data about its in vitro activity against unusual yet clinically relevant gram-positive microbes with reduced susceptibility to vancomycin, including Listeria monocytogenes and Pediococcus, Leuconostoc, Rhodococcus, and Nocardia spp., remain scarce (3,11,13,14,18). All of these pathogens can cause invasive diseases, including bacteremia, pulmonary infections, and soft tissue infections, which usually occur in immunocompromised but occasionally in immunocompetent hosts (1,3,9,13,17).…”

Impacts of Rhodococcus equi on Acquired Immunodeficiency Syndrome: A Review

“…In another case of a 63-year-old non-transplant recipient, non-HIV infected Caucasian woman with endometrial carcinoma who developed recurrent bloodstream infections and septic shock due to R. equi and ultimately required the removal of her port catheter, a subcutaneous implantable central venous catheter [5][6][7]. In this subpopulation of patients, such infections portend high mortality rates and usually require prolonged treatment with multiple antibiotics [8][9][10][11][12][13][14][15][16][17]. Similar patient was a 29-year-old man with autoimmune hepatitis who was undergoing treatment with prednisone and 6-mercaptopurine and presented with fever and cavitary pneumonia and cultures of samples from the lung abscess yielded pleomorphic, gram-positive coccobacilli that were identified as R. equi.…”