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Endophthalmitis is perhaps the most feared complication of cataract surgery, with a reported incidence between 0.07% and 0.13%.1,2 The most common organisms reported in previous studies are Gram positive staphylococci and streptococci.3,4 We report a case of severe endophthalmitis with an unusual Gram positive organism, after uncomplicated phacoemulsification, with foldable intraocular lens implantation.
A 66 year old white man underwent routine phacoemulsification cataract extraction with posterior chamber lens implantation (Acrylic, Model Hydroview H60M, Bausch & Lomb) to the right eye in January 2002.
The left eye had previously undergone similar surgery in September 2001. He was generally in good health, and on no medication. There was a past medical history of sarcoidosis treated with oral prednisolone in 1970, which has since been in remission, and an episode of staphylococcal septicaemia in 1987, without sequelae.
On the first postoperative day, visual acuity measured 6/9 unaided and ocular examination was unremarkable. That same afternoon the patient developed ocular pain, initially relieved by paracetamol (acetaminophen), which however, worsened during the night with progressive deterioration of vision. He presented to the ophthalmic emergency department the following morning with the aforementioned symptoms. Visual acuity was reduced to hand movements right eye and 6/9 left eye. Slit lamp examination revealed an oedematous cornea with Descemet’s folds. The anterior chamber was hazy, with 1 mm hypopyon and the intraocular pressure measured 38 mm Hg.
There was no red reflex. B-scan ultrasound examination showed extensive vitreous debris with attached retina. The left eye was pseudophakic with no abnormalities of note. A diagnosis of acute postoperative endophthalmitis was made. Anterior chamber and vitreous samples were obtained for aerobic and anaerobic culture/sensitivity and Gram staining. Intravitreal vancomycin 2 mg and amikacin 300 μg, each in 0.1 ml of balanced salt solution and subconjunctival cefuroxime 125 mg were administered. Oral ciprofloxacin 500 mg twice daily, prednisolone 60 mg once a day, topical gentamicin hourly, ofloxacin hourly, and atropine 1% twice a day were commenced.
Preliminary Gram staining suggested a Gram positive coccus, sensitive to ciprofloxacin—oral and topical antibiotics were therefore continued. Owing to difficulty in identifying the nature of the organism, the samples were sent to a regional reference laboratory, which identified Gemella haemolysans from both anterior chamber and vitreous aspirates. The organism was reported to be sensitive to gentamicin, ciprofloxacin, laevofloxacin, amoxicillin/clavulanate, chloromycetin, and resistant to trimethoprim.
The patient continued to make steady progress; 2 months later vision had improved to 6/9 unaided. The patient at that time was troubled by floaters secondary to considerable vitreous debris. At last review in September 2002, visual acuity had further improved to 6/4 with −0.75DSph correction.
Gemella haemolysans is an aerobic or facultative anaerobic, Gram positive coccus, a normal commensal of the oral cavity and upper respiratory tract of low virulence.5,6 Systemic infection may lead to septic shock, meningitis, arthritis, or pneumonia, all of which are rare. Identification is difficult. Though Gram positive, the cocci are easily decolorised and hence may appear Gram variable or even negative.
Initially Gemella was included under the genus Neisseria but is now classified as a separate genus within the family Streptococcacea.7 No studies on susceptibility to antiseptics have been published, though there is no reason to believe that it may be resistant to povidone-iodine preparations. The organism is susceptible in vitro to penicillin, streptomycin, vancomycin, chloramphenicol, and tetrasulphathiazole.
A literature search revealed only one previously reported case of infection by Gemella haemolysans, with keratitis and consecutive endophthalmitis.6 Interestingly this patient was reported to have active sarcoidosis on systemic steroid therapy, whereas our patient had a past history of sarcoidosis. This possible association between sarcoidosis and infection by Gemella may be purely coincidental, as no such association has been reported with systemic infection.
Gemella haemolysans is difficult to identify, because of its close resemblance to viridans streptococcus and Neisseria. As diagnostic technology improves, Gemella haemolysans endophthalmitis may be described more often in the future. This report highlights the importance of infection with rare commensal organisms in healthy, immunocompetent individuals after uneventful phacoemulsification cataract surgery.