Bevacizumab prior to vitrectomy for diabetic traction retinal detachment

PURPOSE

To assess the efficacy and safety of preoperative intravitreal bevacizumab (IVB) before vitrectomy for diabetic tractional retinal detachment (TRD).

METHODS

Using ICD-9 codes, we located all patients with diabetic TRD who underwent 3-port 20-gauge vitrectomy primarily performed by one surgeon between January 2004 and January 2009. Eyes receiving IVB were compared with those not. The following outcomes were compared: visual acuity (VA), duration of surgery, and complication rates.

RESULTS

A total of 99 eyes of 90 patients were included in the analysis. In all, 34 patients received IVB on an average of 11.5 (range, 3-30) days previtrectomy. Age was 46.5 and 51.6 in the IVB and non-IVB groups, respectively. VA was improved significantly in both groups: from 20/617 to 20/62 in the IVB group, and from 20/443 to 20/86 in the non-IVB group (P=0.11 between groups). Operating time and postoperative complications (glaucoma, RD, and revitrectomy rate) were similar in both groups. On comparing IVB and non-IVB eyes in younger patients (≤ 40), operating time was shorter (P=0.02) and a trend to better VA in the IVB group was seen.

CONCLUSIONS

Preoperative IVB may be a useful adjunct to vitrectomy for severe PDR complicated by TRD, particularly in younger diabetics.

Optic neuritis in an urban black African community

PURPOSE

To describe the clinical profile of idiopathic optic neuritis in South African blacks.

METHODS

South African black patients with acute isolated idiopathic optic neuritis, treated and followed for at least 3 months at a large medical centre, were studied. Exclusion criteria were other causes of optic neuropathy (such as ischaemic optic neuropathy, toxins or Leber's hereditary optic neuropathy); all causes of optic neuritis (such as HIV, neurosyphilis, sarcoid or connective tissue disease); neurological disease outside of the optic nerves; and any race other than South African black. Patients underwent extensive ophthalmic, neurological, radiological, cerebrospinal fluid and blood assessment.

RESULTS

Eighteen eyes of 10 patients were studied. The mean age was 35.7 years and 9 patients were female. Only 2 patients had truly unilateral optic neuritis, the other 8 having either bilaterally simultaneous or consecutive disease. Presenting visual acuity (VA) was less than 6/60 in 17 of 18 eyes, with severe dyschromatopsia in all eyes. Fifteen eyes had optic disc swelling. All patients were treated with corticosteroids. After at least 3 months follow-up only 6 eyes recovered VA of 6/12 or better, with only 3 eyes recovering colour vision of 10/13 or better on Ishihara plate testing. No patient had multiple sclerosis (MS) on presentation, nor developed MS on follow-up.

CONCLUSION

Idiopathic optic neuritis in black South Africans differs from that in whites. The higher prevalence of bilateral cases and of optic disc swelling, the weaker association with MS and the extremely poor visual outcome distinguish optic neuritis in black South Africans.

Activated human T-cells bestow T-cell antigens to non-T-cells by intercellular antigen transfer

The mechanism of the appearance of T-cell antigens on B-cells, following in vitro activation of peripheral blood lymphocytes, was analyzed using the following model: Purified T-cell suspensions were activated by exposure to phytohemagglutinin (PHA) for 3 days, and then incubated for one hour in the presence of cells of either Raji or K562 cells. The expression of T-cell antigens on the cell lines was determined using immunofluorescent F(ab)2 fragments of monoclonal antibodies (mAbs). Following exposure of the CD19+ Raji cells to activated T lymphocytes, 87.6% of the CD19+ cells coexpressed CD2. A large proportion of the CD19+ cells also expressed CD4, CD5, and CD8 antigens. Similar results were obtained with Raji cells that were prelabeled with calcein AM. In Raji cells, which were rendered CD5+ following incubation with activated T cells, only a negligible level of CD5 mRNA was detected with a sensitive RT-PCR technique, probably attributable to contamination with T cells. K562 cells incubated with activated T cells acquired CD2 but not the CD4 and CD8 antigens. Exposure of either Raji or K562 cells to mAb against CD58 inhibited the transfer of CD2. The present study indicates that following their activation, T-cells gain the capacity to transfer T-cell antigens to non-T cells and that CD2 and CD58 molecules are involved in this process.