Listeria monocytogenes endophthalmitis following keratoconjunctivitis
A 27-year-old healthy white male presented with history of mucopurulent conjunctivitis that was treated with topical tobramycin eye drops for 5 days prior to presentation. After 21 days, he complained of redness and photophobia in the right eye followed by decrease in vision in the same eye. The patient reported a history of photorefractive keratectomy in both eyes 6 months prior to presentation. There was no history of trauma or contact lens wear.\nOn eye examination, the best corrected visual acuity in the right eye was hand motion, and in the left eye was 20/20. Intraocular pressure was 18 mmHg in the right eye and 13 mmHg in the left eye. Slit-lamp biomicroscopy of the right eye revealed keratitis with severe corneal edema. The anterior chamber was deep and showed brown pigmented hypopyon. The left eye was normal. Diagnostic B-scan ultrasonography of the right eye was performed and showed exudates and opacification of the vitreous. After 2 days, a vitreous biopsy was done and intravitreal injection of vancomycin 1 mg/0.1 mL and ceftazidime 2.25 mg/0.1 mL were given. Gram stain showed multiple Gram-positive bacilli. The culture revealed growth that was labeled as contamination.\nThe patient was kept on topical tobramycin and systemic amoxicillin and clavulanate antibiotics, but there was no improvement. The clinical picture of endophthalmitis started to be established with profound loss of vision, hypopyon, and massive vitritis. Four days following the initial tap, the patient was taken to the operating room again and an anterior chamber paracentesis was done and aqueous specimens obtained. Anterior chamber washout and vitreous biopsy were performed. The patient received intracameral antibiotics comprising vancomycin 1 mg/0.1 mL, ceftazidime 2.25 mg/0.1 mL, and cefuroxime 1 mg/0.1 mL at that time. Vitreous tap was taken and intravitreal antibiotics comprising vancomycin 1 mg/0.1 mL and ceftazidime 2.25 mg/0.1 mL were given again. The samples were sent for microbiology and polymerase chain reaction. The result from the aqueous tap was positive for L. monocytogenes that was resistant to most drugs except for penicillin and aminoglycosides. The polymerase chain reaction for aqueous and vitreous tap was negative. A diagnosis of L. monocytogenes-induced endophthalmitis was made. The patient was hospitalized and received intravenous penicillin 0.5 million units every 6 hours, and fortified gentamicin drops were applied hourly to the right eye for 7 days. The ocular inflammations subsided. However, eye examinations revealed that the shallow anterior chamber progressively became flat; the cornea remained edematous; the pupil showed 360° posterior synechiae; the lens was cataractous; and the posterior pole was obscured over the course of 2 weeks. A diagnostic B-scan was performed and showed diffuse thickening of the retinochoroidal layer, but no choroidal detachment (). Ultrasound biomicroscopy revealed a thick cornea; lens displacement anteriorly, almost touching the cornea; and a 360° shallow ciliary body detachment. The condition progressed and the eye developed phthisis bulbi 4 months after onset.