Ocular infections due to non-tuberculous mycobacteria

To investigate the types and causes of non-tuberculous ocular infections and study their response to topical antibiotic therapy.

A single center, retrospective review of 18 patients with non-tuberculous mycobacterial ocular infections, seen over a 3 year period was done. Laboratory diagnosis was established by growth on blood agar, LJ medium and Ziehl-Nielsen acid fast stain.

Out of 18 patients, six had post corneal graft infection, six had corneal ulcers, three had endogenous endophthalmitis, one had post operative endophthalmitis and two cases were of post surgical wound infection. History of trauma was reported in two cases and surgery in nine cases. M. chelonae was grown in blood agar for all patients. For corneal infections fortified genatmicin and fortified amikacin topical eye drops were given while the cases of endophthalmitis received intravitreal amikacin. Response to treatment was poor in 16 cases (88.9%). Only two cases of corneal ulcer improved after prolonged treatment. There was a misdiagnosis of Corynebacterium spp. on Gram stain in the initial cases. Majority of the isolates were sensitive to gentamicin (72.2%) followed by amikacin (44.4%).

Early clinical recognition and prompt laboratory diagnosis together with aggressive topical antibiotic therapy may shorten morbidity and improve the clinical outcome of non-tuberculous mycobacterial ocular infection.