Home Ahead of print Instructions Contacts
About us Current issue Submit article Advertise  
Editorial board Archives Subscribe Login   

 Table of Contents  
Year : 2011  |  Volume : 17  |  Issue : 2  |  Page : 86-88

Otomastoiditis by Mycobacterium fortuitum: A rare case

Department of Microbiology, Smt. Kashibai Navale Medical College and Hospital, Pune, Maharashtra, India

Date of Web Publication20-Dec-2011

Correspondence Address:
Archana Wankhade
Department of Microbiology, Smt. Kashibai Navale Medical College and Hospital, Pune, Maharashtra
Login to access the Email id

Source of Support: None, Conflict of Interest: None

DOI: 10.4103/0971-7749.91046

Rights and Permissions

We report a case of a 26-year-old female patient diagnosed with chronic otomastoiditis caused due to Mycobacterium fortuitum. Definitive identification of pathogen was done on the basis of growth characteristics and biochemical reaction. M. fortuitum was isolated from the lesion. M. fortuitum is a rarely reported cause of otitis media and mastoiditis. The isolate showed resistance to antitubercular drugs and sensitivity to amikacin, ciprofloxacin and imipenem.

Keywords: Mycobacterium fortuitum, Nontuberculous mycobacteria, Otomastoiditis

How to cite this article:
Wankhade A, Ghadage D, Mali R, Bhore A. Otomastoiditis by Mycobacterium fortuitum: A rare case. Indian J Otol 2011;17:86-8

How to cite this URL:
Wankhade A, Ghadage D, Mali R, Bhore A. Otomastoiditis by Mycobacterium fortuitum: A rare case. Indian J Otol [serial online] 2011 [cited 2023 Mar 22];17:86-8. Available from: https://www.indianjotol.org/text.asp?2011/17/2/86/91046

  Introduction Top

Infection of middle ear is a common problem. The usual pathogens causing middle ear infection are the bacteria. It is not well appreciated, however, that Mycobacterium is occasionally associated with middle ear infection. Cases of otitis media and mastoiditis due to nontuberculous mycobacteria (NTM) are very rare. NTM which include Mycobacterium fortuitum, Mycobacterium chelonae, Mycobacterium abcessus are rapidly growing mycobacteria and widely distributed in nature. [1] Identification and isolation of NTM is helpful for the management of patients as the treatment for M. tuberculosis and NTM varies. [2] A case of otomastoiditis due to M. fortuitum is reported in this study. M. fortuitum causes variety of cutaneous diseases, but rarely disseminated infection.

  Case Report Top

A 26-year-old female presented with pain and discharge from the right ear since 3 months. The patient had symptoms of giddiness and severe headache. She had fever for 2 months, associated with giddiness, loss of appetite and loss of weight. On examination, the patient was febrile, without any significant local or regional lymphadenopathy. Clinically, it was diagnosed as chronic suppurative otitis media. X-ray examination showed the inflammatory signs in mastoid area. Chest X-ray was normal. Results of laboratory investigations were all normal including WBC count and erythrocyte sedimentation rate. Serostatus of the patient was normal.

Debridement of mastoid was done. Pus was aspirated from the mastoid under all aseptic precautions and was sent for culture and Ziehl-Neelsen (Z-N) staining in microbiology laboratory. Pus was yellowish in color and thick in consistency. Gram stain examination revealed plenty of pus cells with no organism. Z-N stain revealed acid-fast bacilli [Figure 1]. No growth was observed in routine culture for aerobic and anaerobic organisms. Sample was inoculated in duplicate on Lowenstein-Jenson's slopes (LJ slopes). LJ showed growth which was observed within 5 days [Figure 2]. Colonies were smooth white, creamy and easily emulsifable with no pigmentation. Z-N stain of the colony showed acid-fast bacilli. Gram stain of the colony showed no organism. The organism was presumptively identified as rapid grower, NTM. Further identification of the isolate was done on the basis of rate of growth, and colony morphology and biochemical test.
Figure 1: Z-N staining of pus showing acid fast bacilli with pus cells

Click here to view
Figure 2: L-J medium showing smooth white creamy colonies

Click here to view

Subculture of the colony on LJ medium was done and incubated at 25°C and 45°C. Photochromic and scotochromic character was also observed by incubation in light and dark, respectively. There was growth at 25°C and 45°C. Pink-colored colonies were seen on subculture in MacConkey medium after 3 days of incubation at 37°C. Semi-quantitative catalase test was strongly positive; heat-stable catalase test and nitrate reductase test were also positive. In addition, iron uptake test, urease test and 5% salt tolerance test were positive, and niacin test was negative. These results confirmed the identification of organism to be M. fortuitum. Sensitivity was tested on Muller Hinton agar by Kirby Bauer disc diffusion method. [3] It was sensitive to ciprofloxacin (5 μg), amikacin (30 μg) and imipenem (10 μg), and was resistant to tetracycline (30 μg), linezolid (30 μg), and cefoxitin (30 μg), chloramphenicol (10 μg) and erythromycin (15 μg).

Consecutive samples taken at an interval of 1 week showed growth of M. fortuitum in culture. Repeated isolation confirmed the diagnosis of M. fortuitum. The patient was treated with amikacin and cefoxitin. No duration of therapy or outcome was reported.

  Discussion Top

In a developing country, the incidence of infection due to NTM is still increasing, while in developing countries like India tuberculosis is still a major health problem. [4] Mycobacterium tuberculosis, Mycobacterium bovis and Mycobacterium leprae are the established pathogens. [5] Predominating human mycobacterial infections, NTM are increasingly being reported as etiological agents for human infections but rarely as the cause of otomasoiditis. [6]

Acute otomastoiditis is an inflammation process in the mastoid region, frequently complicated by acute or subacute otitis media. Cervical lymph node is the frequently invaded site of otolaryngological field by NTM, while middle ear space is rarely involved. [7]

Otomastoiditis due to NTM has been reported from patients of all age groups. [2] Conventional methods have been used for identification of the pathogen. Z-N stain cannot differentiate between M. tuberculosis and NTM. Culture is necessary for identification of NTM. Even if automated systems and molecular methods are available for the identification of NTM, in resource-limited centers, phenotypic methods are helpful for their identification and speciation.

Pseudomonas aeruginosa, Streptococcus pneumoniae, Streptococcus pyogenes and methicillin-resistant Staphylococcus aureus have been proved as the common pathogens causing otomasoiditis. [8] In our study, M. fortuitum was isolated from the specimen. Distribution of NTM and incidence of disease caused by them is not fully understood. M. fortuitum has been commonly reported to cause skin and soft tissue infections and wound infections and injection abscess. [4],[8] Otomastoiditis due to M. tuberculosis has been reported. [9]

Even as the presence of acid-fast bacilli was reported on smear examination, a high degree of suspicion is needed to specifically identify whether the pathogen is M tuberculosis or NTM. NTM are resistant to antitubercular drugs like para-aminosalicylic acid, streptomycin and isoniazid. They are susceptible to amikacin, cefotaxin and often to tetracycline, but prolonged treatment for 5-6 months is essential to eradicate the infectious foci. The isolated M. fortuitum was resistant to tetracycline, linezolid, and cefoxitin, chloramphenicol and erythromycin, and was sensitive to ciprofloxacin, amikacin, and imipenem.

Our aim is to focus the attention of ENT specialists toward this pathological agent causing otomasoiditis. Efforts should be made to isolate and speciate NTM, as treatment is not same for all mycobacterial species. This case report illustrates the importance of microbiologic examination and culture.

  References Top

1.Kazda JF. The principle of ecology of Mycobacteria. In: Stanford JL, Ratledge C, editors. Biology of mycobacteria. Vol 1. Massachusetts: Academic Press; 1983. p. 323-42  Back to cited text no. 1
2.Plemmons RM, McAllister CK, Liening DA, Garces MC. Otitis media and mastoiditis due to Mycobacterium fortuitum: Case report, review of four cases, and a cautionary note. Clin Infect Dis 1996;22:1105-6.  Back to cited text no. 2
3.Wallace RJ Jr, Davasio JR, Pankey GA. Disk diffusion testing of susceptibility of Mycobacterium fortuitum and Mycobacterium chelonei to antibacterial agents. Antimicrob Agents Chemother 1979;16:611-4.  Back to cited text no. 3
4.Jesudesan MV, Gladstone P. Non tuberculous mycobacteria isolated from clinical specimens at a tertiary care hospital in South India. Indian J Med Microbiol 2005;23:172-5.  Back to cited text no. 4
5.Ferreira RM, Saad MH, Silva MG, Fonseca Lde S. Nontuberculous mycobacteria I: One year clinical isolates identification in Tertiary Hospital Aids Reference Center, Rio de Janeiro, Brazil, in pre highly active antiretroviral therapy era. Mem Inst Oswaldo Cruz 2002;97:725-9.  Back to cited text no. 5
6.Ingen J, Looijmans F, Mirck P, Dekhuijzen R, Boeree M, van Soolingen D. Otomastoiditis caused by Mycobacterium abscessus, the Netherlands. Emerg Infect Dis 2010;16:166-8.  Back to cited text no. 6
7.Lowry PW, Jarvis WR, Oberle AD, Bland LA, Siberman R, Bocchini JA, et al. Mycobacterium chelonae causing otitis media in an ear nose and throat practice. N Engl J Med 1988;319:978-82.  Back to cited text no. 7
8.Devi DR, Indumati VA, Indira S, Babu PR, Sridharan D, Belwadi MR. Injection site abscess due to Mycobacterium fortuitum: A case report. Indian J Med Microbiol 2003;21:133-4.  Back to cited text no. 8
[PUBMED]  Medknow Journal  
9.Mahajan M, Agarwal DS, Singh NP, Gadre DJ. Tuberculosis of the middle ear - a case report Indian J Tub 1995;42:55.  Back to cited text no. 9


  [Figure 1], [Figure 2]


    Similar in PUBMED
   Search Pubmed for
   Search in Google Scholar for
 Related articles
    Access Statistics
    Email Alert *
    Add to My List *
* Registration required (free)  

  In this article
Case Report
Article Figures

 Article Access Statistics
    PDF Downloaded346    
    Comments [Add]    

Recommend this journal