Berent L M, Messick J B, Cooper S K
Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Illinois, Urbana 61802, USA.
Am J Vet Res. 1998 Oct;59(10):1215-20.
To develop a test for detection of Haemobartonella felis, using a polymerase chain reaction (PCR) assay.
4 adult cats seronegative for FeLV and feline immunodeficiency virus.
Cats were infected with H felis by i.v. administration of 1 ml of blood obtained from an infected cat. Rectal temperature, PCV, and microscopic examination of blood smears for organisms were monitored daily. At peak of infection, doxycycline treatment was initiated for 21 days. Blood samples were collected at weekly intervals. Six months after treatment, 2 cats were given methylprednisolone (14 mg/kg of body weight, i.m.). Daily blood samples were collected for CBC, detection of organisms, and PCR evaluation. On the basis of the 16S rRNA gene sequence of H felis, specific PCR primers were created for a 393-basepair internal fragment.
The 393-basepair product was consistently amplified from blood samples obtained during peak parasitemia but not during the last week of or immediately after completion of doxycycline treatment. After treatment, PCV returned to the reference range, and organisms were not observed in blood samples; however, the PCR product could be consistently amplified. After administration of methylprednisolone, organisms were only rarely observed in blood smears but were consistently detected by PCR analysis.
Using PCR analysis, it was possible to detect H felis in blood samples obtained from cats during peak parasitemia, during most of the carrier phase, and after challenge with immunosuppressive drugs. During and immediately after antibiotic treatment, this test may fail to detect the organisms.
采用聚合酶链反应（PCR）分析法开发一种检测猫血巴尔通氏体的试验。
4只对猫白血病病毒（FeLV）和猫免疫缺陷病毒血清学阴性的成年猫。
通过静脉注射1毫升从感染猫获得的血液，使猫感染猫血巴尔通氏体。每天监测直肠温度、红细胞压积，并对血涂片进行显微镜检查以查找病原体。在感染高峰期，开始用强力霉素治疗21天。每周采集血样。治疗6个月后，给2只猫注射甲基强的松龙（14毫克/千克体重，肌肉注射）。每天采集血样进行全血细胞计数、病原体检测和PCR评估。根据猫血巴尔通氏体的16S rRNA基因序列，设计针对一个393碱基对内部片段的特异性PCR引物。
在寄生虫血症高峰期采集的血样中始终能扩增出393碱基对的产物，但在强力霉素治疗最后一周或治疗刚结束后则不能。治疗后，红细胞压积恢复到参考范围，血样中未观察到病原体；然而，PCR产物仍能持续扩增。注射甲基强的松龙后，血涂片仅偶尔观察到病原体，但PCR分析始终能检测到。
通过PCR分析，能够在寄生虫血症高峰期、大多数携带期以及用免疫抑制药物激发后，从猫的血样中检测到猫血巴尔通氏体。在抗生素治疗期间及刚结束后，该试验可能无法检测到病原体。
