Vechi Hareton Teixeira, Oliveira Eduardo Teodoro Gurgel de, Freitas Marise Reis de, Rossi Flávia, Britto Maria Helena Marques Fonseca de, Alves Manoella do Monte
Universidade Federal do Rio Grande do Norte, Departamento de Infectologia, Natal, Rio Grande do Norte, Brazil.
Universidade de São Paulo, Faculdade de Medicina, Hospital das Clínicas, Divisão Laboratório Central, São Paulo, São Paulo, Brazil.
Rev Inst Med Trop Sao Paulo. 2018 Nov 14;60:e74. doi: 10.1590/S1678-9946201860074.
Rhodococcus equi is a facultative aerobic, intracellular, non-motile, non-spore-forming, Gram-positive, weakly acid-fast coccobacillus belonging to the group of nocardioform actinomycetes. R. equi infections are rare opportunistic illnesses in patients with Acquired Immunodeficiency Syndrome (AIDS), associated with a high mortality rate. The most common clinical presentation of R. equi infections is a chronic cavitary pneumonia. Due to its acid-fastness, R. equi can be mistaken for others acid-fast organisms, as Mycobacterium tuberculosis. In turn, R. equi is also a gram-positive pleomorphic bacteria and can be mistaken for diphtheroids or Micrococcus organisms, being accidentally disregarded as oral contaminants in sputum cultures. Therefore, in Brazil, a highly prevalent tuberculosis (TB) country, pulmonary infections caused by R. equi may mimic pulmonary TB and represent a diagnostic challenge. Here, we report on a case of chronic cavitary pneumonia by R. equi in a Human Immunodeficiency Virus (HIV)-infected patient, focusing on diagnostic aspects.
马红球菌是一种兼性需氧、细胞内寄生、无运动性、不形成芽孢、革兰氏阳性、弱抗酸的球杆菌，属于诺卡氏菌样放线菌属。马红球菌感染在获得性免疫缺陷综合征（AIDS）患者中是罕见的机会性疾病，死亡率很高。马红球菌感染最常见的临床表现是慢性空洞性肺炎。由于其抗酸性，马红球菌可能会被误认为是其他抗酸菌，如结核分枝杆菌。反过来，马红球菌也是一种革兰氏阳性多形性细菌，可能会被误认为是类白喉杆菌或微球菌属细菌，在痰培养中被意外地当作口腔污染物而被忽视。因此，在结核病（TB）高度流行的巴西，马红球菌引起的肺部感染可能会模仿肺结核，构成诊断挑战。在此，我们报告一例人类免疫缺陷病毒（HIV）感染患者发生的马红球菌所致慢性空洞性肺炎病例，重点关注诊断方面。
