Validation of a diagnostic multiplex polymerase chain reaction assay for infectious posterior uveitis.

OBJECTIVE: To validate a multiplex polymerase chain reaction (PCR) assay capable of simultaneously screening vitreous biopsy specimens for a panel of common pathogens in posterior uveitis. METHODS: A multiplex PCR assay using novel primer sets for cytomegalovirus (CMV), herpes simplex virus (HSV), varicella zoster virus (VZV), and Toxoplasma gondii was developed. The sensitivity of the assay was determined for purified pathogen DNA. Twenty-one vitreous specimens from patients with posterior uveitis were tested by both multiplex and monoplex PCR. RESULTS: Fewer than 10 genomes of VZV and fewer than 100 genomes of HSV, CMV, and T gondii could be detected using the new primer sets. When used in multiplex, the assay lost less than 1 log of sensitivity. Monoplex PCR detected pathogen DNA in 18 of 21 patient samples; multiplex PCR detected pathogen DNA in 15 of the 18 samples positive by monoplex PCR. None of 10 negative control samples were positive for pathogen DNA. CONCLUSIONS: Multiplex PCR has adequate sensitivity to simultaneously screen a substantial differential diagnosis for posterior uveitis in a single reaction, without loss of specificity. This assay may reduce the time and cost involved in PCR-based molecular diagnostics of infectious pathogens. CLINICAL RELEVANCE: Mutiplex PCR may allow rapid diagnosis of infectious posterior uveitis.

Selective management of double elevator palsy by either inferior rectus recession and/or knapp type transposition surgery.

BACKGROUND AND PURPOSE: Double elevator palsy (DEP) is a monocular elevation deficiency in abduction and adduction characterized by hypofunction of the superior rectus (SR) and inferior oblique muscles. Only a limited number of studies are published on the management of this problem. Therefore, we studied and report and add our experience with emphasis on the indications and types of surgery for DEP. PATIENTS AND METHODS: The records of 18 patients with DEP out of 3612 strabismic cases (0.5%) were reviewed. Fourteen underwent surgery. Inferior rectus (IR) recession was performed in cases with positive forced ductions (Group 1, n=6). In patients with negative forced duction test (Group 2, n=8) and in patients whose vertical deviation was not corrected with IR recession, transposition surgery (Knapp or modified Knapp procedure) was performed. A hypotropia of less than 5 PD postoperatively was considered a "successful" outcome. RESULTS: In Group 1, "IR recession only", the mean preoperative vertical deviation was 29.2 PD +/-3.8 PD SD. The vertical deviation was adequately corrected after IR recession in only one patient; the other 5 patients then underwent transposition surgery at 6 months postop'. After the second operation, the mean corrected deviation for Group 1 overall was 25.8 PD +/-5.6 PD with an overall 33% surgical success rate. In Group 2, "primary transpositions", the mean preoperative vertical deviation and the mean corrected deviation were 23.9 PD +/-6.7 PD and 18.6 PD +/-4.4 PD respectively, and the surgical "success" rate was 63%. The mean corrected deviation for all cases was 21.7 PD +/-4. 9 PD and the overall surgical "success" rate was 57%. CONCLUSION: Surgical intervention should be selective according to DEP clinical features. The surgical effect of transposition surgery may be enhanced by IR recession.

Late bleb-related endophthalmitis after trabeculectomy with mitomycin C.

To present two cases of delayed-onset postoperative endophthalmitis following trabeculectomy combined with mitomycin C for secondary glaucoma after penetrating keratoplasty. We retrospectively evaluated two patients with late endophthalmitis after trabeculectomy combined with intraoperative mitomycin C application. Both patients underwent trabeculectomy for uncontrolled glaucoma following penetrating keratoplasty and they developed thin-walled cystic blebs. Intraocular pressure was normal, and grafts remained clear postoperatively. Severe endophthalmitis with hypopyon developed at 3 and 7 months postoperatively. Both patients had concomitant bleb infection. They underwent vitreous sampling and intravitreal injection of vancomycin and amikacin and were given topical fortified and systemic antibiotic therapy. Intravitreal injection was repeated once in both patients. Cultures grew Streptococcus pneumonias in one and Staphylococcus aureus in the other. Although the treatment of endophthalmitis was successful in both patients, only one of them achieved useful vision (20/40). For the other patient who had been infected with S. pneumoniae, vision was light perception. Delayed-onset endophthalmitis following trabeculectomy with mitomycin C application is a severe and vision threatening complication. It seems that the development of thin cystic filtering blebs secondary to intraoperative mitomycin C application may be a predisposing factor for bleb-related late endophthalmitis.