Postoperative endophthalmitis

SUBCONJUNCTIVAL ANTIBIOTICS IN THE TREATMENT OF ENDOPHTHALMITIS MANAGED WITHOUT VITRECTOMY

PURPOSE

To determine if the treatment outcomes for endophthalmitis are influenced by subconjunctival antibiotics.

METHODS

A retrospective, nonrandomized consecutive series of patients with clinically diagnosed bacterial endophthalmitis confirmed with positive cultures who presented between December 1, 1995, and February 28, 2002, was studied. Patients with cataract surgery, glaucoma filtering blebs, or trauma who presented with visual acuity of hand motions or better were included. All patients received intravitreal and topical antibiotics. Management by pars plana vitrectomy or vitreous tap and use or nonuse of subconjunctival antibiotics were at the discretion of the treating physician.

RESULTS

There were 59 patients identified; 54 met the follow-up criteria. These patients were divided into two groups based on whether subconjunctival antibiotics were used (group ABX; n = 21) or not used (group noABX; n = 33). The median pretreatment visual acuity was hand motions in both groups. The median age in both groups was 74 years. Etiology, duration of symptoms, vitreous culture organisms, percentage of cases with wound complications such as leaks or vitreous incarceration, and intraocular lens type were similar in the two study groups. Intravitreal and topical antibiotics and corticosteroids used were not significantly different in the two groups, except that topical ceftazidime was used less frequently in group ABX than in group noABX (43% vs. 82%, respectively; P = 0.007). The median follow-up was 13 months in both groups (range: 3-87 months for group ABX and 3-63 months for group noABX). Final visual acuity in groups ABX and noABX was at least 20/50 (33% vs. 39%, respectively), 20/60 to 5/200 (29% vs. 39%, respectively), 4/200 to better than hand motions (0 vs. 3%, respectively), or hand motions or worse (38% vs. 18%, respectively). These differences were not significant (P = 0.37). Reinjection rates (14% vs. 15%, respectively) were also similar in groups ABX and noABX. The additional procedures rate was significantly higher in group ABX than in group noABX (P = 0.024), with cumulative rates of 33% and 3%, respectively, at the 12-month follow-up.

CONCLUSIONS

These data suggest that subconjunctival antibiotics may not be necessary to treat infectious endophthalmitis managed with otherwise standard tap and injection techniques and topical antibiotics.

Occlusive scrub suits in operating theaters during cataract surgery: effect on airborne contamination

The effect of wearing occlusive scrub suits on bacterial contamination of air was studied during cataract operations. All personnel regularly wore cotton scrub suits. During the intervention period, all wore occlusive scrub suits, which, compared with cotton scrub suits, were associated with more than a 50% reduction in the load of airborne bacteria during operations.

Endophthalmitis

Endophthalmitis is an inflammatory reaction of intraocular fluids or tissues. Infectious endophthalmitis is one of the most serious complications of ophthalmic surgery. Occasionally, infectious endophthalmitis is the presenting feature of an underlying systemic infection. Successful management of infectious endophthalmitis depends on timely diagnosis and institution of appropriate therapy. Recognition of the different clinical settings in which endophthalmitis occurs and awareness of the highly variable presentation it may have facilitate timely diagnosis. Biopsy of intraocular fluid/tissue is the only method that permits reliable diagnosis and treatment. The different presenting clinical settings, a rational approach to diagnosis (i.e., when, what, and how to biopsy), and the treatment of infectious endophthalmitis are reviewed.

Advances in rapid laboratory diagnosis of infectious endophthalmitis

Infectious endophthalmitis is a serious ocular condition which always requires rapid medical or surgical intervention. At present this, in a number of situations, remains empirical as a consequence of problems inherent in unequivocal identification of the causative organism, should one be present. Aqueous humor smears and culture have limited value in diagnosis. Vitreous samples can often reveal the presence of microbes, but these may not necessarily be detected in all cases, principally due to suboptimal sampling or pretreatment with antimicrobials which render microbes non-culturable on routine media. Use of electron microscopy and/or immunocytochemistry offers an alternative means of identification, but these approaches have drawbacks principally associated with interpretation. Molecular methods which identify conserved sequences from common causative microbes of endophthalmitis, or which can specify whether the organism is a bacterium or a fungus may become especially important as diagnostic tools in this clinical scenario.

Intraocular contamination during extracapsular cataract extraction with intraocular lens implantation

Ocular bacterial contamination has been studied in 45 eyes that underwent cataract surgery. The following samples were taken: (1) eyelid margin swab; (2) conjunctival swab; (3) aqueous humor after initial anterior chamber penetration; (4) anterior capsule fragment after capsulorrhexis or capsulotomy; (5) cortical lens material; (6) anterior chamber fluid after lens implantation. The percentages of contaminated samples were 15.5, 13.3, 0.0, 11.1, 13.3 and 6.6, respectively. There was a significant difference between the incidence of positive cultures in the aqueous humor at the time of incision and in subsequent intraocular samples. Positive cultures were found in 13 out of 45 eyes, only gram-positive organisms were recovered and coagulase-negative staphylococci were the most common (78.5% of the isolates). These results confirm previous reports on intraocular contamination during cataract surgery.

Endophthalmitis after lens extraction

This article describes most features of endophthalmitis after lens extraction: symptomatology, differential diagnosis, prognosis, treatment and prevention. Literature findings are compared to the author's proper extensive experience with endophthalmitis. Cultures have been positive in 153 cases. A hundred and fifteen of them were seen after previous ocular surgery. Amongst these cases 104 were seen after cataract surgery.

Intracapsular and extracapsular pseudophakic endophthalmitis: a comparison

A hundred and four cases of post cataract endophthalmitis with positive vitreous cultures are discussed. Functional results depend largely on the infecting agent but even after Staphylococcus epidermidis infections some eyes may be lost. Although post lens surgery endophthalmitis carries the best prognosis in the endophthalmitis group, 40% of the eyes are lost, sometimes caused by a delayed vitrectomy decision. Comparing intracapsular and extracapsular lens surgery two big differences were noted: (1) the bacteriology, and (2) the functional results. The bacteriological spectrum of the ICCE was composed of 1/3 of S. epidermidis, 70% of Gram + cocci and 80% of Gram+organisms. After extracapsular lens extraction the majority of cases (60%) were caused by S. epidermidis (statistical significance 0.01). The difference in functional result is explained by the difference in bacteriology: if only the S. epidermidis cases are compared, functional results between both categories are nearly equal. ECCE seems to make the eye more vulnerable to infection by a low virulent agent.

Endophthalmitis at the Bristol Eye Hospital: an 11-year review of 47 patients

We reviewed data from 47 patients who were treated for endophthalmitis at our hospital during the 11-year period 1980-90. The most common clinical features were hypopyon (75%), diminished vision (72%), ocular pain (68%), discharge (57%), corneal oedema (51%), conjunctival injection (49%), abnormal red reflex (34%), corneal ulcer (32%) and corneal perforation (6%). A total of 54 isolates were obtained from 41 (87%) of the 47 patients. Gram-positive bacteria were more common (72%), than Gram-negative organisms (22%). Two cases were due to fungi, and herpes simplex virus was isolated from one case. The two most common Gram-positive organisms were coagulase-negative staphylococci (25%), and Staphylococcus aureus (11%), while Pseudomonas aeruginosa predominated among the Gram-negative bacteria isolated (15%). Mixed bacterial species were obtained from 29% of the infected patients, including one from whom Vibrio fluvialis was isolated. Predisposing factors included ocular surgery (60%)--mostly for cataract extraction (47%), penetrating trauma (15%) and periocular (15%) or systemic (11%) infections. All patients received antibiotics (generally chloramphenicol and/or a beta-lactamase-stable penicillin plus an aminoglycoside) prior to culture, when treatment was adjusted according to specific aetiological agents. Seventy-nine per cent of patients received topical or systemic steroids. Vitrectomy (diagnostic and therapeutic) was performed on 21% of patients. Sixty-three per cent of culture-positive patients lost vision (no perception of light) in the affected eye, compared to 17% of culture-negative cases (P < 0.05 Fisher exact test). Similarly, a better visual outcome (acuity of 6/12 or better) was associated with coagulase-negative staphylococcal infection than with streptococcal or fungal infections.(ABSTRACT TRUNCATED AT 250 WORDS)