A case of postoperative endophthalmitis by extended-spectrum beta-lactamase-producing Escherichia coli

Postoperative exogenous endophthalmitis caused by Escherichia coli: a rare case report and literature review

Aim: We report a rare case of postoperative endophthalmitis caused by Escherichia coli. Case description: The diagnosis of postoperative endophthalmitis in our patient was established based on the clinical signs of hypopyon along with vitritis. The patient underwent pars plana vitrectomy, anterior chamber washout, intraocular lens removal, and intravitreal antibiotics (amikacin and vancomycin) injection. The culture of both the vitreous sample and the intraocular lens, revealed a heavy growth of Escherichia coli. Conclusion: Escherichia coli is an unusual microorganism to cause postoperative endophthalmitis. A major breach in the sterilization may explain this infection. Proper sterilization and prophylactic measures are crucial to avoid this disastrous complication.

Escherichia coli Panophthalmitis after Pecking by a Great Egret (Ardea alba)

We report a case of open globe injury caused by Ardea albapecking that resulted in Escherichia colipanophthalmitis. A woman in her 70s complaining of ocular pain was referred to our hospital because her right eye had been pecked by an A. alba2 days earlier. Visual acuity in her right eye was reduced to light sensation. The right conjunctiva became hyperemic and edematous with swelling of the right upper eyelid. The upper side of the right cornea was densely cloudy with focal defect. Ultrasonography showed a thick sclera and choroid-like structure. Pathological investigation of a scraped sample from the infected site revealed gram-negative rods; E. coli was isolated. She had fever with elevated serum C-reactive protein levels and leukocytosis confirmed by laboratory examination. Topical levofloxacin and cefmenoxime and intravenous fosfomycin and aspoxicillin were initiated, but the right cornea melted near the perforated site with leakage of the eyeball contents on the next day. We decided to perform eye evisceration because of difficulty in controlling corneal melting and panophthalmitis. Her general state recovered the day after surgery. Orbital cellulitis improved gradually with normal C-reactive protein levels and white blood cell counts. As ocular injury caused by birds could become severe and cause ocular infection and visual dysfunction, it is important to exercise caution in the vicinity of wild birds, especially when they are aggressive.

Development of a novel reverse transcriptase polymerase chain reaction to determine the Gram reaction and viability of bacteria in clinical specimens

OBJECTIVE

To develop a novel RNA based assay to determine the Gram reaction and viability of bacteria in clinical specimens.

MATERIALS AND METHODS

Reverse transcriptase PCR (RT-PCR) targeting 16SrRNA region was optimized using Staphylococcus aureus ATCC 25923 and Pseudomonas aeruginosa ATCC 27853 by using two novel sets of primers. Sixty clinical specimens consisting of 31 intraocular specimens (19 vitreous fluids and 12 aqueous humor), 11 peripheral blood specimens and 18 other clinical specimens were subjected to standard microbiological culture and RT-PCR to determine the Gram reaction and viability of bacteria. The amplified products were subjected to DNA sequencing to identify the bacterium.

RESULTS

The sensitivity of RT-PCR was 0.4fg and the primers amplified bacterial cDNA. RT-PCR detected the presence of bacteria in 60 clinical specimens indicating the presence of viable bacteria. Concordant results were obtained with both primer sets. Seventy five bacterium comprising 52 single (69.3%) and 23 mixed bacteria (30.6%), both Gram positive and Gram negative were detected. These results correlated with the bacterial identity by PCR based DNA sequencing.

CONCLUSION

RT-PCR is a reliable tool to identify the presence of viable bacteria and to precisely determine Gram reaction.