#IDBR
35M cystic fibrosis / recurrent lung infection
After Caribbean trip: one-month history of pain in forearm. Imaging / PE: flexor tenosynovitis.
During trip: fishing, kayaking, swimming; had a tattoo in arm.
Work up: HIV (-); Quantiferon-TB +
Culture of tissue biopsy:

2/
Diagnosis: #Mycobacterium #marinum #tenosynovitis
Clues: water exposure, subacute clinical presentation, false-positive Quantiferon-TB test

3/
#IDBR associations
M #avium is a common colonizer and may cause infection in patients with cystic fibrosis
M #fortuitum (rapid grower AFB) have complicated tattoo procedures
M #gordonae is rarely associated with clinical illness; often a contaminant from environment

4/
#Quantiferon-TB IGRA is known to be cross-reactive with the following NTMs:
M #marinum
M #kansasii
M #szulgai
Other NTMs sporadically reported to cross-react:
M fortuitum
M gordonae
M porcinum