Clinical and microbiological profile of non-tuberculous mycobacterial endophthalmitis—experience in a tertiary eye care centre in Southern India

BACKGROUND Endophthalmitis caused by non-tuberculous mycobacteria (NTM) is a rare condition seen after surgery and trauma. This study reports a retrospective, consecutive, non-comparative case series of 5 patients referred to L. V. Prasad Eye Institute, Hyderabad, and diagnosed with culture-proven NTM endophthalmitis between January 2004 and April 2015. Data collected included demographic information, presenting features, microbiology investigation, treatment course, and final visual outcome. RESULTS Of 5555 clinically diagnosed infective endophthalmitis patients, vitreous samples were culture positive for bacteria in 1541 (27.7 %). The isolates from five (0.32 %) patients were identified as NTM. The clinical settings included post-cataract surgery (n = 3), post-vitrectomy (n = 1), and Descemet's stripping endothelial keratoplasty (n = 1). The species of NTM identified were Mycobacterium chelonae (n = 3), Mycobacterium manitobense (n = 1), and Mycobacterium fortuitum (n = 1). All isolates were sensitive to amikacin while three of the five isolates were sensitive to vancomycin. Initial treatment strategies included pars plana vitrectomy with intravitreal antibiotic (vancomycin and amikacin) injection (n = 3), additional intraocular lens explant (n = 1), and silicone oil removal in the patient with post-vitreo-retinal surgery. Intravitreal steroid along with antibiotics were given in three patients. Final outcome was favourable (20/200) in one patient, two eyes had unfavourable outcome with multiple recurrences, one was advised evisceration, and one resulted in phthisis bulbi. CONCLUSIONS This communication reports a series of five cases of NTM endophthalmitis. Poor outcome despite cultureguided therapy suggests virulent nature of the organisms and the need for better treatment strategies.