Baker T F, McEwen S A, Prescott J F, Meek A H
Department of Veterinary Microbiology and Immunology, Ontario Veterinary College, University of Guelph.
Can J Vet Res. 1989 Jul;53(3):290-4.
An abattoir survey was undertaken to determine the prevalence of leptospirosis and its association with lesions of multifocal interstitial nephritis (so-called "white spotted kidneys") in swine at slaughter. Both cross-sectional and case-control study designs were used. Of 197 kidneys from hogs randomly selected at slaughter, 11 (5.6%) had generalized grey-white foci typical of multifocal interstitial nephritis (MFIN). Antibody titers greater than or equal to 1:80 against Leptospira pomona were detected in nine (4.6%) hogs and against L. bratislava in 63 (32%) of these hogs. Leptospira pomona (kennewicki) was detected by immunofluorescence in 5/197 (2.5%) of randomly selected hogs. Leptospires identified as genotype kennewicki were isolated from six (9.8%) of 61 kidneys cultured. Leptospira bratislava was not detected by immunofluorescence or culture. There was a highly significant (p = 0.00) and strong association (odds ratio (OR) = 195) between high L. pomona titer (greater than or equal to 1:80) and the presence of leptospires in the kidneys, as detected by culture. There was also a significant (p = 0.046) and strong (OR = 8.10) association between multifocal interstitial nephritis and the presence of renal leptospires as detected by culture. The association between leptospiral titer and MFIN lesions in the prevalence survey group of animals was statistically significant (p = 0.031), but this association was not significant in the case-control study group (p = 0.071) The failure to identify L. bratislava despite serological evidence of infection suggests that some of these seropositive animals may have been transiently infected at an early age, that serological findings were falsely positive, or that immunofluorescence and isolation attempts failed to detect L. bratislava if they were indeed present in the kidneys.(ABSTRACT TRUNCATED AT 250 WORDS)
开展了一项屠宰场调查，以确定猪群中钩端螺旋体病的流行率及其与屠宰时多灶性间质性肾炎（所谓“白斑肾”）病变的关联。采用了横断面研究和病例对照研究设计。在屠宰时随机选取的197头猪的肾脏中，11个（5.6%）有典型的多灶性间质性肾炎（MFIN）的灰白色病灶。在9头（4.6%）猪中检测到抗波摩那钩端螺旋体的抗体效价大于或等于1:80，在其中63头（32%）猪中检测到抗布拉迪斯拉发钩端螺旋体的抗体效价。通过免疫荧光法在随机选取的197头猪中的5头（2.5%）检测到波摩那钩端螺旋体（肯尼维奇型）。从61个培养的肾脏中的6个（9.8%）分离出鉴定为肯尼维奇基因型的钩端螺旋体。未通过免疫荧光法或培养检测到布拉迪斯拉发钩端螺旋体。培养检测发现，高波摩那钩端螺旋体效价（大于或等于1:80）与肾脏中钩端螺旋体的存在之间存在高度显著（p = 0.00）且强关联（比值比（OR）= 195）。培养检测还发现，多灶性间质性肾炎与肾脏中钩端螺旋体的存在之间存在显著（p = 0.046）且强关联（OR = 8.10）。在动物流行率调查组中，钩端螺旋体效价与MFIN病变之间的关联具有统计学意义（p = 0.031），但在病例对照研究组中该关联不显著（p = 0.071）。尽管有感染的血清学证据，但未鉴定出布拉迪斯拉发钩端螺旋体，这表明这些血清学阳性动物中的一些可能在幼年时曾短暂感染，血清学结果为假阳性，或者如果肾脏中确实存在布拉迪斯拉发钩端螺旋体，免疫荧光法和分离尝试未能检测到它。（摘要截短于250字）
