High prevalence of haemoglobin S in the closed Egyptian community of Siwa Oasis.

BACKGROUND: Sickle cell haemoglobinopathy, the most frequent of the hereditary anomalies of haemoglobin, occurs most commonly in individuals of African descent. With a population of about 23 000, Siwa Oasis is situated in the Western Desert of Egypt, close to the Libyan border. It is Egypt's most remote oasis town and the Siwans have developed their own distinct Berber culture. Siwans represent a closed isolated community suffering from various health problems, among which is haemolytic anaemia.

OBJECTIVES: This study aimed at screening primary school children of Siwa Oasis for abnormal haemoglobin (Hb) profiles and determining the prevalence of Hb S among them.

MATERIALS AND METHODS: This descriptive and analytic study included 349 primary school children of both sexes, 153 males and 196 females with a male to female ratio of 1:1.3. Their ages ranged between 6 and 12 years. All subjects were screened for abnormal Hbs using complete blood counts and capillary Hb electrophoresis.

RESULTS: Out of a total of 349 primary school children screened, 22% (77/349) were having abnormal Hb profiles, of whom 88% (68/77) had Hb S (ie, sickle cell disorder) constituting 20% of the total population studied. 94% of those having Hb S (64/68) had sickle cell trait (ie, Hb S less than 50%) constituting 18% of the total population screened, while 6% had sickle cell disease, having more than 50% Hb S.

CONCLUSIONS: The closed Egyptian community in Siwa Oasis has a high frequency of Hb S carriers and so represents one of the targets of prevention programmes to be implemented in Egypt in order to reduce the economic burden of health services for treating patients with sickle cell disease.

TRIAL REGISTRATION NUMBER: 1-25/15-1-2014.