Purpose: To report an atypical case of primary meningococcal keratitis in a myopic contact lens wearer, with typical clinical features resembling acanthamoeba keratitis. This case report emphasizes the significance of early diagnosis, investigations, and management of primary meningococcal keratitis. 

Case-report: This is a single-patient case report describing an 18-year-old male, contact lens wearer, who presented with 1 month history of left eye redness, and discomfort. His initial exam showed a semi-ring-shaped infiltrate, and cultures confirmed the presence of Neisseria meningitidis. 

Results: Based on the initial clinical suspicion of acanthamoeba keratitis, the patient was managed by total superficial keratectomy, which was sent for corneal gram stain, culture and histopathology. Topical hourly moxifloxacin hydrochloride ophthalmic solution 0.5% and propamidine isotheonate 0.1% ophthalmic solution and chlorhexidine gluconate 0.02% ophthalmic solution. Following the culture confirmed pathogen, infectious disease team was consulted and a systemic treatment with 7 days of intravenous ceftriaxone 2 grams per day was given. He had persistent epithelial defect that resolved after 3 weeks from the initial visit on intense regimen of ocular lubrication. 

Conclusion: This case report highlights an atypical presentation of culture confirmed primary neisseria meningitidis keratitis presenting with a ring-shaped infiltrate. Misdiagnosis or inappropriate treatment, such as the use of steroids, can exacerbate the condition. When evaluating contact lens wearers presenting with a ring-shaped infiltrate, n. meningitidis may be considered as a potential causative pathogen. However, in view of both the potential ocular and systemic sequelae of n. meningitidis infection, it is important to investigate and treat these patients promptly and aggressively