Neisseria sicca: A Rare Cause of Bacterial Conjunctivitis

Patient: Male, 34-year-old Final Diagnosis: Conjunctivitis • Keratitis • Neisseria sicca Symptoms: Eye pain and redness • eyelid swelling • pus discharge Medication: — Clinical Procedure: — Specialty: Ophthalmology OBJECTIVE: Rare disease BACKGROUND: Neisseria-associated conjunctivitis is a rare cause of bacterial conjunctivitis in adults, with Neisseria gonorrhoeae as the primarily identified infectious strain. Here, we present a rare case of bacterial conjunctivitis due to Neisseria sicca in a 34-year-old immunocompetent man with no prior medical or ocular history. CASE REPORT: A 34-year-old man with no significant past medical or ocular history presented with a 3-day history of left peri-orbital edema, ocular pain, and copious purulent discharge. Bacterial conjunctivitis was suspected due to the rapidity of onset and purulence. Peripheral corneal thinning was identified. Preliminary culture results showed gram-negative diplococci, and the patient was treated for gonococcal infection. Final cultures identified Neisseria sicca, a rarely pathogenic strain of Neisseria species. CONCLUSIONS: This is the second reported case of Neisseria sicca-associated conjunctivitis, and the first reported case to have corneal involvement. Neisseria sicca, while typically non-pathogenic, may manifest as conjunctivitis in immuno-competent hosts with a low-risk sexual history.