Çelebi Bekir, Yeşilyurt Murat, Kılıç Selçuk
Ministry of Health, General Directorate of Public Health, Department of Zoonotic and Vector Disease, Ankara, Turkey.
Ministry of Health, Tekirdağ State Hospital, Infectious Diseases Clinic, Tekirdag, Turkey.
Mikrobiyol Bul. 2018 Oct;52(4):431-438. doi: 10.5578/mb.67139.
Rickettsia species are gram-negative intracellular, small pleomorphic coccobacilli in the Rickettsiaceae family. This genus is serologically and genotypically divided into four groups as spotted fever group, typhus group, Rickettsia belli and Rickettsia canadensis. Rickettsia conorii (R.conorii subsp. conorii) in the spotted fever group was reported to cause mediterranean spotted fever in Europe, especially in mediterranean countries including Turkey. The major vectors of Rickettsia species are ticks, and in some species fleas or mites. In this report a case with R.conorii infection was presented. A 46-year-old female patient, who had anorexia, fatigue, muscle aches, chills and high fever was admitted to a health institution. The patient was diagnosed as influenza. There was no regression in the patient's complaints with the recommended treatment. The patient was examined in our infectious diseases clinic and had several symptoms like severe muscle and joint pain with significant headache, and rashes at her body including hands and feet. The patient had a single eschar in the upper midline of the belly that matched tick biting and pink small maculopapular scars on the trunk, arms, legs, feet, and hands. Considering a Rickettsia pre-diagnosis, liquid electrolyte and doxycycline 2 x 100 mg oral treatment was started. On the third day of treatment, high fever, muscle and joint pain were decreased. On the fifth day, active skin lesions were started to fade. R.conorii IgM and IgG were negative in the first serum sample of the patient. In the biopsy sample taken from eschar tissue, Rickettsia spp. was detected as positive with rt-PCR. PCR was used by using the specific regions of the genetically specific gltA and ompA genes in the biopsy specimens and then the PCR products were determined by DNA sequence analysis. The DNA sequence results were compA red with Genbank data and determined that the gltA sequence was 99%, similar to R.conorii with accession number JN182786 and the ompA sequence was 99%, similar to R.conorii with accession number KR401144. When the phylogenetic tree was created, it was observed that the etiological agent was R.conorii. A week after the treatment, in the second serum sample R.conorii IFA IgM 1/192 titer and IgG 1/320 titer were detected as positive. In this case report, we have presented a Rickettsia case, clinically diagnosed as Rickettsia, serologically negative in the acute phase, PCR positive, with post-treatment seroconversion and etiologic agent determined as R.conorii.
立克次体属细菌是革兰氏阴性的细胞内寄生菌，是立克次体科中形态多样的小型球杆菌。该属在血清学和基因分型上分为四组，即斑点热群、斑疹伤寒群、贝氏立克次体和加拿大立克次体。斑点热群中的康氏立克次体（康氏立克次体亚种康氏立克次体）据报道在欧洲可引起地中海斑点热，尤其是在包括土耳其在内的地中海国家。立克次体属细菌的主要传播媒介是蜱，在某些种类中是跳蚤或螨。在本报告中，介绍了一例康氏立克次体感染病例。一名46岁女性患者，出现厌食、疲劳、肌肉疼痛、寒战和高热，入住一家医疗机构。该患者被诊断为流感。按照推荐治疗后患者的症状并无缓解。该患者在我们的传染病诊所接受检查，出现了多种症状，如严重的肌肉和关节疼痛、剧烈头痛，以及包括手脚在内的全身皮疹。患者腹部上中线处有一个单一的焦痂，与蜱叮咬相符，躯干、手臂、腿部、脚部和手部有粉红色的小斑丘疹疤痕。考虑到立克次体的初步诊断，开始进行液体电解质补充及口服2×100mg强力霉素治疗。治疗第三天，高热、肌肉和关节疼痛减轻。第五天，活动性皮肤病变开始消退。患者的第一份血清样本中康氏立克次体IgM和IgG均为阴性。在从焦痂组织采集的活检样本中，通过逆转录聚合酶链反应（rt-PCR）检测到立克次体属细菌呈阳性。在活检标本中使用遗传特异性的柠檬酸合酶（gltA）基因和外膜蛋白A（ompA）基因的特定区域进行聚合酶链反应（PCR），然后通过DNA序列分析确定PCR产物。将DNA序列结果与基因库数据进行比较，确定gltA序列与登录号为JN182786的康氏立克次体相似度为99%，ompA序列与登录号为KR401144的康氏立克次体相似度为99%。构建系统发育树时，观察到病原体为康氏立克次体。治疗一周后，在第二份血清样本中检测到康氏立克次体间接免疫荧光抗体试验（IFA）IgM滴度为1/192、IgG滴度为1/320呈阳性。在本病例报告中，我们呈现了一例立克次体病例，临床诊断为立克次体感染，急性期血清学阴性，PCR阳性，治疗后血清转化，病原体确定为康氏立克次体。
