Dengue maculopathy: a case report.

INTRODUCTION: Dengue fever is endemic in many countries of South East Asia. In spite of the occasional epidemics, dengue maculopathy remains a rare entity. CASE HISTORY: A 31-year-old gentleman was admitted with a 6-day history of fever, generalised rash, headache and myalgia after a trip to Malaysia. There were no bleeding manifestations. The lowest platelet count was 71 x 10,000/ml, the haematocrit was 42.7%, and dengue serology was positive. On the 8th day of illness, he complained of bilateral blurred vision. Detailed visual examination showed visual acuity of right eye 6/30 and left eye 6/50. Fundoscopy revealed dilated veins, hyperaemic optic discs, flame and blot haemorrhages, soft exudates and macular ischaemia. After a course of high-dose steroids, the visual acuity as well as colour vision improved markedly. DISCUSSION: The pathology of maculopathy is not obvious in this case, but an immunological reaction is suspected. There is a risk of residual visual impairment, and there is no definitive treatment. The use of high-dose steroids seemed to improve visual acuity and colour vision. However, it is not known whether immunosuppression improves the prognosis. Time for resolution is from 8 weeks to 4 months. Since there is an increase in the incidence of dengue fever in our region, coupled with rising international travel, one could postulate that global incidence of dengue-related maculopathy may become significant. CONCLUSION: Ocular complications associated with dengue fever are rare but may result in permanent visual impairment. Dengue fever should be suspected in travellers, particularly those returning from endemic areas, and they should be systematically screened for maculopathy when visual disturbances arise.

Pyrexia of unknown origin: Kikuchi-Fujimoto disease.

A case of Kikuchi-Fujimoto disease is presented in the context of pyrexia of unknown origin. Although no specific etiology has been identified, several reported cases are associated with a variety of viruses, toxoplasma, or systemic lupus erythematosus. We present a case and discuss the implications for management.

Comparison of TAP2 frequencies in type 1 diabetes patients and healthy controls from three ethnic groups indicates an African origin for the TAP2 G allele.

In order to determine the ethnic origin of the transporter associated with antigen processing 2 (TAP2) G allele, initially discovered by us in a group of type 1 diabetes (insulin-dependent diabetes mellitus) patients living on Reunion Island, HLA TAP2 typing was performed using the polymerase chain reaction-amplification refractory mutation system (PCR-ARMS) method in type 1 diabetes patients and unrelated healthy controls of three different ethnic groups (Caucasians, Indians and black Africans from Senegal and Mauritius). The comparison of TAP2 allele frequencies in controls showed significant racial (ethnic) differences. The TAP2*0101 and TAP2 C alleles were increased, respectively, in the Caucasian (50% in Caucasians vs. 40% in other groups) and Senegalese (27% in Senegalese vs. 10% in other groups) populations. In comparison with Caucasians, the TAP2*0201 variant was significantly increased in the Indian population and decreased in the Senegalese black population. In addition, the TAP2 G allele was observed in the two African populations studied but not in the Caucasian or Indian population. This observation is consistent with the view that this allele is restricted to populations of African origin. In addition, we have determined the large extended haplotype DQA1-DQB1-DRB1 associated with TAP2 G. We found that this allele is preferentially associated with the large conserved haplotype HLA DQA1*0501-DQB1*0201-DRB1*0301.

Spectrum of beta thalassemia mutations and their linkage to beta-globin gene haplotypes in the Indo-Mauritians.

The beta thalassemia alleles in 53 thalassemic Indo-Mauritian patients and their families consisting of 23 homozygous beta-thalassemia, 9 HbE/beta-thalassemia, 18 HbS/beta-thalassemia, 1 HbD/beta-thalassemia, 1 deltabeta/beta-thalassemia and 1 HbH/beta-thalassemia from the island of Mauritius were studied. Characterization by polymerase chain reaction-based reverse dot blot hybridization technique revealed that the IVS1-5 (G-->C) mutation accounted for 74% of the beta thalassemic alleles, while six other mutations occurred at much lower frequencies: HbE codon 26 (G-->A); 10.4%, codon 8/9 (+G); 3.5%, codon 30 (AGG-->ACG) also called IVSI (-1).G-->C; 3.5%, codon 15 (G-->A); 3.5%, codon 41/42 (-CTTT); 2.4% and -28 (A-->G); 2.4%. Association of these mutations to specific beta globin gene sequence framework and haplotype allowed to trace their ancestral link. These data are useful in future molecular screening of the population in view of implementing a thalassemia prevention and control program in Mauritius.

Asthma mortality in Mauritius: 1982-1991.

BACKGROUND: Bronchial asthma is a common problem in the island of Mauritius and its prevalence seems to be increasing. OBJECTIVE: In order to appreciate the magnitude of the problem, patterns of asthma mortality were studied during a period of 10 years. METHOD: All death certificates issued in the island from 1982 to 1991 were reviewed and all cases of asthma deaths were selected. RESULTS: The global asthma mortality rate was found to be 20/100,000 in 1982, and it decreased to 12/100,000 in 1991. Similarly the asthma death rate for the 0 to 4 year age group decreased from 20/100,000 in 1982 to 5/100,000 in 1991. For the 5 to 34 year age group, it decreased from 2.6/100,000 in 1982 to 1.02/100,000 in 1991. There was no statistically significant difference between the various ethnic groups. CONCLUSION: Our study showed that in a developing country such as Mauritius asthma death rates may be high but may show decreasing trends. Nevertheless, it is generally perceived that the prevalence of the disease is increasing.