TY - JOUR AU - Linder, Regina T1 - Rhodococcus equi and Arcanobacterium haemolyticum: Two "Coryneform" Bacteria Increasingly Recognized as Agents of Human Infection T2 - Emerging Infectious Disease journal PY - 1997 VL - 3 IS - 2 SP - 145 SN - 1080-6059 AB - Rhodococcus equi and Arcanobacterium haemolyticum, formerly classified in the genus Corynebacterium, are members of the loosely defined taxon "coryneform" bacteria. Although they are the etiologic agents of distinct human infections, both organisms are frequently overlooked, which results in missed or delayed diagnoses. R. equi, long known as an important pathogen of immature horses, has become in the past three decades an opportunistic pathogen of severely immunosuppressed humans. Most cases are secondary to HIV infection. When specifically sought in throat swab cultures, A. haemolyticum is found responsible for 0.5% to 2.5% of bacterial pharyngitis, especially among adolescents. These two microorganisms represent a spectrum of disease in humans: from a mild, common illness to a rare life-threatening infection. Each organism elaborates lipid hydrolyzing enzymes (cholesterol oxidase by R. equi and sphingomyelinase D by A. haemolyticum) that are toxic to animals and humans and damaging to mammalian cell membranes. The participation of the cytotoxins in pathogenicity is discussed. Greater awareness of the properties of these two bacteria may promote faster, more accurate diagnoses and better clinical management. KW - KW - United States DO - 10.3201/eid0302.970207 UR - https://wwwnc.cdc.gov/eid/article/3/2/97-0207_article ER - End of Reference