Late-onset postoperative Mycobacterium haemophilum endophthalmitis masquerading as inflammatory uveitis: a case report

BACKGROUND: Although atypical mycobacteria had been increasingly found in various ocular infections in the past decades, a slow-growing Mycobacterium haemophilum (M. haemophilum) was scarcely reported. Similar to tuberculous infection, the presentation can masquerade as low-grade granulomatous intraocular inflammation with partial response to corticosteroids. Besides, the special requirements for culture make this pathogen difficult to diagnose. The study aims to report the clinical presentation and notify the awareness of NTM endophthalmitis among clinicians. This is the first case report of late-onset, postoperative M. haemophilum endophthalmitis in the literature. CASE PRESENTATION: A 66-year-old man with non-insulin-dependent diabetes mellitus (NIDDM) manifested chronic granulomatous inflammation in the left eye after multiple glaucoma surgeries. With a diagnosis of noninfectious panuveitis, he was treated with systemic corticosteroids. The inflammation initially responded to therapy although it subsequently worsened and became purulent endophthalmitis. The vitreous cultures grew M. haemophilum. Intraocular and systemic antimicrobial treatments were administered early, but the patient eventually turned blind. CONCLUSIONS: M. haemophilum endophthalmitis is a rare but serious intraocular complication leading to loss of vision or eyeball. Awareness of atypical mycobacterial infections is necessary especially in patients with impaired immune function, previous intraocular surgery, and corticosteroid resistance. Proper laboratory investigations and treatments should be performed. However, due to the rarity of the disease, the development of guidelines for its investigation and therapy is still challenging.