Båverud V, Franklin A, Gunnarsson A, Gustafsson A, Hellander-Edman A
The National Veterinary Institute, SVA, Uppsala, Sweden.
Equine Vet J. 1998 Nov;30(6):482-8. doi: 10.1111/j.2042-3306.1998.tb04523.x.
In Sweden, mares sometimes develop acute, often fatal, colitis when their foals are treated orally with erythromycin and rifampicin for Rhodococcus (R.) equi infection. Clostridium (C.) difficile, or its cytotoxin, was demonstrated in faecal samples from 5 of 11 (45%) mares with diarrhoea. By contrast C. difficile was not found in the faecal flora of 12 healthy mares with foals treated for R. equi infection or in 56 healthy mares with healthy untreated foals. No other enteric pathogen was isolated from any diarrhoeic mare. Of 7 investigated treated foals, 4 had a high (1651.0, 1468.3, 273.0 and 88.8 microg/g) faecal concentration of erythromycin. The dams of those 4 foals developed acute colitis, whereas the dams of 3 foals with a lower (26.3, 4.6 and 3.7 microg/g) faecal erythromycin concentration remained healthy, indicating that there might have been an accidental intake of erythromycin by mares. The foals treated with antibiotics were regarded as asymptomatic carriers and potential reservoirs, as C. difficile was found in 7 of 16 foals investigated, while 56 untreated foals proved negative. The isolated C. difficile strains proved resistant to both erythromycin (MIC>256 mg/l) and rifampicin (MIC>32 mg/l), a fact that may have favoured the growth of C. difficile in the foal intestine. All mares found positive for C. difficile were, or had recently been, hospitalised together with their foals, indicating that C. difficile may be a nosocomial infection, in horses. The results emphasise that routine testing for C. difficile and its cytotoxin is recommended when acute colitis occurs in mares when their foals are treated with erythromycin and rifampicin. Preventive measures in order to avoid accidental ingestion of erythromycin by mares from the treatment of their foals are suggested.
在瑞典，当母马的幼驹口服红霉素和利福平治疗马红球菌（R. equi）感染时，母马有时会患上急性、通常致命的结肠炎。在11匹腹泻母马中的5匹（45%）粪便样本中检测到艰难梭菌（C. difficile）或其细胞毒素。相比之下，在12匹接受过马红球菌感染治疗的健康母马及其幼驹，以及56匹幼驹未接受治疗的健康母马的粪便菌群中未发现艰难梭菌。从任何腹泻母马中均未分离出其他肠道病原体。在7匹接受调查的接受治疗的幼驹中，4匹粪便中红霉素浓度较高（分别为1651.0、1468.3、273.0和88.8微克/克）。这4匹幼驹的母马患上了急性结肠炎，而3匹粪便中红霉素浓度较低（分别为26.3、4.6和3.7微克/克）的幼驹的母马保持健康，这表明母马可能意外摄入了红霉素。接受抗生素治疗的幼驹被视为无症状携带者和潜在储存宿主，因为在16匹接受调查的幼驹中有7匹检测到艰难梭菌，而56匹未接受治疗的幼驹检测结果为阴性。分离出的艰难梭菌菌株对红霉素（MIC>256毫克/升）和利福平（MIC>32毫克/升）均耐药，这一事实可能有利于艰难梭菌在幼驹肠道内生长。所有检测出艰难梭菌呈阳性的母马都曾或最近与其幼驹一起住院，这表明艰难梭菌在马中可能是一种医院感染。结果强调，当母马在其幼驹接受红霉素和利福平治疗时发生急性结肠炎时，建议对艰难梭菌及其细胞毒素进行常规检测。建议采取预防措施，以避免母马在治疗幼驹时意外摄入红霉素。
