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CaseIsolation Report of fortuitum from BACTEC 9240 System

Isolation of from BACTEC 9240 Blood Culture System: A Case Report

Fang-Lan Yu1, Jau-Ching Lee1, Tsung-Han Wu2, Yi-Lin Liang1, Chia-Wen Lin1, Tzu-Ting Chen1, Giueng-Chueng Wang1 1Department of Laboratory Medicine 2Tuberculosis center Taipei Medical University-Wan Fang Hospital

We describe an 89-year-old male patient who admitted due to pneumonia documented bacteremia by isolating Mycobacterium fortuitum (M.fortuitum) from BACTEC 9240 blood culture system in April 2009. During his admission, two sets of blood culture were reported as positive. Microscopic examination revealed atypical gram-positive bacilli and acid-fast organism. This organism was subsequently identified as M. fortuitum. Concerning that M. fortuitum could be cultured and iso- lated in this case, not only owing to it is a rapidly growing mycobacteria, but also the professional- ism that the experienced technicians have. Laboratory staff should have awareness of performing mycobacteria culture when encountering an atypical gram-positive accompanying with delayed aerobic culture result. Key words: Rapidly growing mycobacteria, Mycobacterium fortuitum, BACTEC 9240 Blood Culture System

M. fortuitum is a gram-positive and acid-fast bacilli. It is also a saprophyte whose natural habitat includes Introduction , water and dust. Nowadays M. fortuitum is increas- ingly recognized as an opportunistic pathogen causing Runyon described the four groups of non-tuberculous disseminated [3-5]. Clinical presentation of M. mycobacteria (NTM), a grouping that encompasses all fortuitum includes mainly cutaneous and soft tissue in- mycobacteria outside of the Mycobacterium fections, localized posttraumatic wound , sur- complex, according to pigment production and rate of gical wound infections and keratitis [6-8]. In general, growth in 1959 [1]. These are Runyon Group I: the immunocompetent patients tend to experience limited photochromogens, Runyon Group II: the scotochro- infections associated with low mortality. mogens, Runyon Group III: the nonchromogens, which Bacteremia is a serious clinical condition which can are classified as slowly growing mycobacteria, and Runyon lead to death, and consequently a rapid and accurate de- Group IV: the rapid growers, which may be photochro- tection and identification of the pathogen plays the cru- mogenic, , or more usually nonchro- cial role in effective treatment. More than one blood mogenic, are defined as visible growth on Löwen- sample are collected and examined to detect the micro- stein-Jensen slant medium (Becton Dickinson) within organism exists and, to identify its , and to deter- seven days on subculture [2]. Mycobacterium fortuitum mine its drug susceptibility. (M.fortuitum) is a member of the rapidly growing It goes without saying that shortening the turn- Runyon Group IV NTM. Besides M. fortuitum, the around time of microbiological analyses is fairly sig- common organisms of Runyon group IV are Mycobacte- nificant and is closely related to declining patients’ mor- rium peregrinum, Mycobacterium senegalense, Myco- bidity and mortality [9-10]. In clinical laboratories, the bacterium abscessus and [1]. BACTEC 9240 blood culture system (Becton Dickinson Received: September 21, 2009 Revised: March 8, 2010 Accepted: April 7, 2010 Address for correspondence: Giueng-Chueng Wang, Department of Laboratory Medicine, Taipei Medical University-Wan Fang Hospital, No. 111, Section 3, Hsing-Long Road, Taipei, Taiwan, R.O.C. TEL:0968-745941 E-mail: [email protected] 70 J Biomed Lab Sci 2010 Vol 22 No 2

Diagnostic Instrument Systems, Sparks, Md.) is one of following microbiological and biochemical reactions the automated, continuous-monitoring and widely ex- were applied. There was growth at 3 days on Löwen- ploited systems [10]. It uses noninvasive fluorescent stein-Jensen slant medium, individual colonies were patented technology to detect increases in CO2 produced smooth and buff colored in the dark and after exposure by microbial growth. Each bottle contains a fluorescent to light. The isolate was positive for arylsulfatase, ni-

CO2 sensor which is monitored every ten minutes for trate, 5% NaCl and urease and negative for niacin and increases in fluorescent appearance. Computer algo- Tween 80 hydrolysis. rithms determine whether sustained linear increases or increasing rates of change in fluorescent indicate micro- bial growth. Commercial bottles are available for every variety of clinical use. For instance, BD BACTEC Plus Aerobic/F and Plus Anaerobic/F media are used in a qualitative procedure for the aerobic and anaerobic cul- ture respectively. Generally speaking, when blood cul- ture bottles were positive, removed them from the BACTEC instrument, the contents were gently mixed, direct Gram staining of the blood culture fluid, and some of the fluid was inoculated onto a combination of agar plates, suited for culturing aerobic, anaerobic, and fas- tidious microorganisms. In this case report, subsequently Fig. 1. Mycobacterium fortuitum ( 1000x) revealed mycobacteria culture should be considerated whenever gram-positive rods suspicion of mycobacterial infection. Finally, identifica- tion of the microorganism and determination of its sus- ceptibility pattern.

Case Report

We describe a case of an 89-year-old male patient with poor-controlled diabetes who was bedridden and under- went a long-term and therapy docu- mented M. fortuitum bacteremia in April 2009. This pa- tient had a prolonged hospitalization for two years be- cause of repeated episodes of pulmonary edema and nosocomial pneumonia. Two sets of blood culture were Fig. 2. Mycobacterium fortuitum ( Ziehl-Neelsen stain1000x) collected appropriately, incubated in BACTEC 9240 showed acid-fast bacilli blood culture system and were positive after 48 hours of incubation. Gram stain of these positive blood culture specimens revealed Gram-positive rods (Figure 1), which were preferred forming bacilli than cocci. Due to no microbial growth on aerobic agar plates in the first two days, we tried to perform Ziehl-Neelsen stain and unexpectedly found the acid-fast bacilli (Figure 2). For further identification, mycobacteria culture was fol- lowed by submitting the positive culture broth to Löwen- stein-Jensen slant medium. The individual colonies dis- played smooth and buff-color appearance both on aero- bic agar plates (Figure 3) and Löwenstein-Jensen slant medium (Figure 4) in the following two and three days. The microorganism was subsequently identified as M. Fig. 3. Smooth and buff-color appearance of Mycobacterium fortuitum by traditional biochemical method [11]. The fortuitum colonies grew on aerobic sheet blood agar plates

J Biomed Lab Sci 2010 Vol 22 No 2 71

Isolation of Mycobacterium fortuitum from BACTEC 9240 Blood Culture System

In view of the predilection groups of mycobacteria infection, it is essential to administer appropriate medi- cal treatment, and therefore the susceptibility testing for mycobacteria is extremely recommended.

References

1. Brown-Elliott, B. A., and R. J. Wallace, Jr.: Clinical and taxonomic status of pathogenic nonpigmented or late-pigmenting rapidly growing mycobacteria. Clin. Mi- crobiol. Rev 2002; 15: 716–746. Fig. 4. The individual colonies of Mycobacterium fortuitum were 2. Wallace, R. J., Jr., B. A. Brown-Elliott, and C. Turenne: smooth and buff colored on Löwenstein-Jensen medium Clinical and laboratory features of Mycobacterium por- cinum. J. Clin. Microbiol 2004; 42: 5689–5697. 3. Corrado Serra, Giovanni Loi, Barbara Saddi, Marisa Pautasso, and Aldo Manzin: Unusual Clinical Presenta- Discussion tion of Mycobacterium fortuitum Infection in an Im- munocompetent Woman. J. Clin. Microbiol 2007; 45: 1663–1665. This is the first case of M. fortuitum isolation from 4. Toı¨di Ade´kambi, Andre´as Stein, Joseph Carvajal, positive blood culture bottle in the laboratory of Taipei Didier Raoult, and Michel Drancourt: Description of My- Medical University- Wan Fang Hospital. According to cobacterium conceptionense sp. nov., a Mycobacterium the manufacturer’s instructions, samples of blood culture fortuitum Group Organism Isolated from a Posttraumatic bottle are going to be asserted negative if BACTEC Osteitis Inflammation. J. Clin. Microbiol 2006; 44: 9240 does not detect the appearance of fluorescence in 1268–1273. 5. M P A Lessing, M M Walker: Fatal pulmonary infection culture bottles within six days. M. fortuitum, a member due to Mycobacterium fortuitum. J Clin Pathol 1993; 46: of rapidly growing Runyon IV NTM, has the property to 271-272. grow on standard mycobacterial media within seven 6. Hsin-Hung Wu, Rong-Luh Lin, Chao-Hsien Lee, days and this property may contribute to the primary Ming-Jen Peng, Chien-Liang Wu: Mycobacterium For- positive culture in blood sample culture system in this tuitum Bacteremia and Pulmonary Disease in a Hemo- case. dialysis Patient. Thorac Med 2007; 22: 332-337. This finding has highlighted that M. fortuitum is not 7. Zainal Muttakin A R, Tan A M: Mycobacterium fortuitum only a well-known acid-fast , but can also forms catheter-related sepsis in acute leukaemia. Singapore Med J 2006; 47: 543-545. diphtheroids, Gram positive rods appearance, under 8. Samuel C M Huang, H Kaz Soong, Jen-Shiang Chang, Gram stain microscopy [1]. Consequently, clinical tech- Yu-Sung Liang: Non-tuberculous mycobacterial keratitis: nicians should show considerable regard for Gram posi- a study of 22 cases. British Journal of Ophthalmology tive diphtheroids, beads or rods from the blood culture 1996; 80: 962-968. sample and should proceed with mycobacteria identifi- 9. Guido Funke and Pascale Funke-Kissling: Use of the BD cation rather than ignore it as contaminants. PHOENIX Automated System for Direct M. fortuitum is ubiquitous in nature and is consid- Identification and Susceptibility Testing of Gram Nega- tive Rods from Positive Blood Cultures in a Three-Phase ered as a non-pathogen to normal people, while it may Trial. J. Clin. Microbiol 2004; 42: 1466–1470. cause opportunistic infection for immunocompromised 10. Marjan J. Bruins, Peter Bloembergen, Gijs J. H. M. Ruijs, patients. In fact, cases of cervical lymphadenitis and and Maurice J. H. M. Wolfhagen: Identification and arisen from M. fortuitum infection in patients Susceptibility Testing of Enterobacteriaceae and Pseu- with immunosuppression, the acquired immunodefi- domonas aeruginosa by Direct Inoculation from Positive ciency syndrome patients for example, have also been BACTEC Blood Culture Bottles into Vitek 2. J. Clin. Mi- reported [3]. Nevertheless, even though bacteremia re- crobiol 2004; 42: 7–11. sulting from M. fortuitum is relatively rare, the incidence 11. Laboratory Manual of Mycobacteria, Taipei: Taiwan CDC, 2004. of such mycobacterium infections is gently growing, and probably becoming common in the future.

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案例報告

自 BACTEC 9240 血液培養系統分離出 Mycobacterium Fortuitum－案例報告

余芳蘭 1 李兆清 1 吳宗翰 2 梁憶林 1 林嘉玟 1 陳姿婷 1 王炯中 1

台北醫學大學‧市立萬芳醫院 1 實驗診斷科 2 結核病中心

我們描述一位89歲的男性病人因為肺炎住院治療，病歷記錄由Mycobacterium fortuitum (M. for- tuitum)引起的菌血症。於住院期間做了兩套血液培養且呈現陽性結果。革蘭氏染色見到不典型陽 性桿菌，推測可能是分枝桿菌，操作抗酸菌染色並呈現陽性結果。經過分枝桿菌培養鑑定出M. fortuitum。此案例的血液培養分離出M. fortuitum，不僅是因為此菌屬於快速生長分枝桿菌，也由 於俱經驗醫檢師的判斷及專業。醫檢師如遇到不典型革蘭氏陽性病原菌且培養需時較長的個案， 應考慮操作分枝桿菌培養。

關鍵詞：快速生長分枝桿菌、Mycobacterium fortuitum、BACTEC 9240 血液培養系統

收稿日期：98 年 9 月 21 日 修稿日期：99 年 3 月 8 日 接受日期：99 年 4 月 7 日 通訊作者：王炯中，台北醫學大學‧市立萬芳醫院 實驗診斷科，台北市興隆路三段 111 號 電話：0968-745941 電子郵件：[email protected]

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