Document Type

Case Report


Higher Education | Infectious Disease | Medicine and Health Sciences


Background: Nontuberculous mycobacteria (NTM) infections are commonly caused by Mycobacterium marinum and fortuitum with M. marinum more likely to cause skin infections. Aquatic environments are a potential source of contact with M. marinum and fortuitum. Patients with NTM infections may present with positive tuberculin purified protein derivative (PPD) and/or gold QuantiFERON tests. However, PPD cannot differentiate between NTM infection and other tuberculous infections caused by different mycobacterial strains. We present a patient a marine biologist who was asymptomatic and presented for further evaluation as she has a h/o positive PPD and gold QuantiFERON test.

Methods: Patient informed consent was obtained for this case report.

Results: A 31 years old, healthy, female marine biologist employed in an aquatic environment presented to the clinic with a positive PPD and a positive gold QuantiFERON test. Her job exposes her to sea creatures that maybe infected with Mycobacterium marinum and fortuitum. She denied any history that was suggestive of tuberculous infection. A referral was made to specialist service for further evaluation at which time a repeat gold QuantiFERON test was performed and was noted to be positive. Following this work up, the patient preferred to follow a conservative treatment approach to monitor for any symptoms of active tuberculosis and seek follow up as needed.

Conclusion: Clinicians should not downplay the importance of aquatic occupations and hobbies in patients who exhibit positive PPD and gold QuantiFERON test. Healthcare providers should consider NTM infection in their differential diagnosis when examining patient populations exposed to aquarium water, saltwater, and freshwater environments. Preventative apparel like waterproof gloves can protect the exposed skin from infection. Clinicians can prevent NTM infections by increasing awareness and promoting prevention measures in at-risk populations, particularly since infection can be prevented from appropriate protective attire.




Mycobacterium marinum, Mycobacterium fortuitum, PPD test, Gold QuantiFERON test, Aquatics, NTM (non-tuberculous mycobacterium), Granuloma.

Creative Commons License

Creative Commons Attribution-Noncommercial-No Derivative Works 4.0 License
This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 4.0 License.



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