Bafghi Mehdi Fatahi, Heidarieh Parvin, Soori Tahereh, Saber Sasan, Meysamie Alipasha, Gheitoli Khavar, Habibnia Shadi, Rasouli Nasab Masoumeh, Eshraghi Seyyed Saeed
PhD, Department of Pathobiology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.
PhD, Department of Bacteriology and Virology, School of Medicine, Alborz University of Medical Sciences, Karaj, Iran.
Germs. 2015 Mar 2;5(1):12-6. doi: 10.11599/germs.2015.1066. eCollection 2015 Mar.
The genus Nocardia is a cause of infection in the lungs, skin, brain, cerebrospinal fluid, eyes, joints and kidneys. Nocardia isolation from polymicrobial specimens is difficult due to its slow growth. Several methods have been reported for Nocardia isolation from clinical samples. In the current study, we used three methods: paraffin baiting technique, paraffin agar, and conventional media for Nocardia isolation from various clinical specimens from Iranian patients.
In this study, we examined 517 samples from various clinical specimens such as: sputum of patients with suspected tuberculosis, bronchoalveolar lavage, sputum of patients with cystic fibrosis, tracheal aspirate, cutaneous and subcutaneous abscesses, cerebrospinal fluid, dental abscess, mycetoma, wound, bone marrow biopsy, and gastric lavage. All collected specimens were cultured on carbon-free broth tubes (paraffin baiting technique), paraffin agar, Sabouraud dextrose agar, and Sabouraud dextrose agar with cycloheximide and were incubated at 35°C for one month.
Seven Nocardia spp. were isolated with paraffin baiting technique, compared with 5 positive results with the paraffin agar technique and 3 positive results with Sabouraud dextrose agar with and without cycloheximide. The prevalence of nocardial infections in our specimens was 5.28%.
In the present study, the use of the paraffin baiting technique appeared to be more effective than other methods for Nocardia isolation from various clinical specimens.
诺卡氏菌属可导致肺部、皮肤、大脑、脑脊液、眼睛、关节和肾脏感染。由于其生长缓慢，从多微生物标本中分离诺卡氏菌很困难。已有多种从临床样本中分离诺卡氏菌的方法被报道。在本研究中，我们使用了三种方法：石蜡诱饵技术、石蜡琼脂和常规培养基，从伊朗患者的各种临床标本中分离诺卡氏菌。
在本研究中，我们检查了517份来自各种临床标本的样本，如：疑似肺结核患者的痰液、支气管肺泡灌洗、囊性纤维化患者的痰液、气管吸出物、皮肤和皮下脓肿、脑脊液、牙脓肿、足菌肿、伤口、骨髓活检和洗胃样本。所有采集的标本均接种于无碳肉汤管（石蜡诱饵技术）、石蜡琼脂、沙氏葡萄糖琼脂以及含放线菌酮的沙氏葡萄糖琼脂上，并在35°C孵育1个月。
通过石蜡诱饵技术分离出7株诺卡氏菌属菌株，相比之下，石蜡琼脂技术有5个阳性结果，含和不含放线菌酮的沙氏葡萄糖琼脂分别有3个阳性结果。我们标本中诺卡氏菌感染的患病率为5.28%。
在本研究中，对于从各种临床标本中分离诺卡氏菌，石蜡诱饵技术似乎比其他方法更有效。
