Retinal Changes in Uncomplicated and Severe Plasmodium knowlesi Malaria.

BACKGROUND: Plasmodium knowlesi causes severe malaria, but its pathogenesis is poorly understood. Retinal changes provide insights into falciparum malaria pathogenesis but have not been studied in knowlesi malaria. METHODS: An observational study was conducted in Malaysian adults hospitalized with severe (n = 20) and nonsevere (n = 24) knowlesi malaria using indirect ophthalmoscopy (n = 44) and fundus photography (n = 29). RESULTS: The patients' median age was 44 years (range, 18-74 years). No coma or deaths occurred. Photography detected retinal changes in 11 of 12 patients (92%) with severe and 14 of 17 (82%) with nonsevere knowlesi malaria. Nonspecific retinal whitening occurred in 3 (35%) and 5 (29%) patients with severe and nonsevere disease, respectively; hemorrhages in 2 (17%) and 3 (18%); loss of retinal pigment epithelium in 1 (8%) and 4 (24%); and drusen in 9 (71%) and 12 (75%). All changes were mild, with no significant differences between severe and nonsevere disease. Patients with retinal hemorrhages had lower platelet counts than those without (median, 22 vs 43 × 10(9)/L; P= .04). CONCLUSIONS: The paucity of specific retinal findings associated with disease severity in knowlesi malaria contrasts with the retinopathy of severe adult falciparum malaria with and without coma, suggesting that falciparum-like microvascular sequestration in the brain is not a major component in severe knowlesi malaria pathogenesis.

Kearns-Sayre syndrome: An unusual ophthalmic presentation.

Kearns-Sayre syndrome (KSS) belongs to the group of neuromuscular disorders known as mitochondrial encephalomyopathies. It has characteristic syndromal features, which include: chronic progressive external ophthalmoplegia, bilateral atypical pigmentary retinopathy, and cardiac conduction abnormalities. So far, only a single case has been reported where a patient with KSS had a normal retina. Herein, we report this extremely rare variant of KSS, which not only presented later than the normal age of presentation, but also had minimal pigmentary retinopathy.