Results:
From the total screened students, 1560 studies were adequate and interpretable according to the criteria specified in the methods section. This revealed a prevalence of 2.3% of the sample with RHD without adding the equivocal cases (Figure 1).
Most of the sample were males (65.8%). Due to the variable distribution among different stages of school, greater proportion were in the primary stage (46%) and the lower number was in the secondary stage (27%) with mean age of the whole sample of 12.9+ 3.4 years. The patients with definite RHD are older with mean age of 13.1+ 3.4 when compared to the other two groups as shown in table 2.
The table also shows what presumed to be the risk factors for developing the disease. However no significant difference was noticed between groups even with univariate analysis shown in table 3 and after adding the equivocal cases to the definite cases. The clinical examination performed by the trained staff is shown in table 2. The discrepancy shown between the confirmed diagnosis and the finding is due to the mild form of the disease found by echocardiography (as stated below). Some of the staff reported the finding as an innocent murmur and others (~1%) reported an MR.
The most prevalent lesion as detected by echocardiography was mitral regurgitation which was observed also in subjects with normal valve morphology however it was in the mild category in those pupils (table 4). The two cases with morphological changes in the mitral valve were diagnosed as mitral valve prolapse not fulfilling the criteria of RHD. Neither of the patients with aortic regurgitation had normal valve morphology.