Dextrocardia and situs inversus in Sri Lanka.

Transposition of the viscera is an uncommon condition but no figures are available as to its prevalence in a tropical country. 31 cases of dextrocardia were seen among 110,603 persons examined at two chest clinics in Sri Lanka. A further 11 cases were detected by the reading of films taken at a tuberculosis prevalence survey in the general population in which 27,095 persons were examined after random selection. The incidence at the chest clinics was 1 in 3567, while the prevalence in the general population was 1 in 2500, perhaps the highest rate to be reported from any country. The prevalence was higher in the rural than in the urban population. All cases were right handed, implying that there was no transposition of the centres in the brain. In one case the mother had mumps in the first trimester of pregnancy, thus raising the possibility of an aetiological relationship.