An unusual case of spontaneous Mycobacterium chelonae corneal ulcer in a healthy middle-aged adult

BACKGROUND: To report a rare presentation of culture-positive Mycobacterium chelonae corneal ulcer and its management. FINDINGS: We report a rare case of a patient with a history of chronic pain and blurriness of vision. Examination revealed a chronic nonhealing paracentral corneal ulcer inferiorly at the 5–7 o’clock meridian with anterior chamber reaction unresponsive to routine antibiotic and antifungal medications with Mantoux test positivity in a middle-aged nondiabetic patient with no prior history of trauma, ocular surgery, and contact lens usage. Ziehl–Neelsen staining of the nonhealing ulcer revealed acid-fast bacilli typical of M. chelonae, with subsequent culture positivity in Löwenstein–Jensen medium. Subsequent treatment with topical fortified amikacin and tobramycin resulted in rapid healing of the corneal ulcer. CONCLUSION: M. chelonae presenting as a chronic nonhealing corneal ulcer spontaneously occurring in a healthy adult with no predisposing factor draws attention towards the need to have a good index of suspicion by performing a Ziehl–Neelsen stain and culture, and subsequent successful management with topical fortified amikacin and tobramycin.