Roughly nine out of every ten cases of rheumatic heart disease that are identified by echocardiography are missed by careful clinical examination with auscultation, according to findings. Roughly nine out of every ten cases of rheumatic heart disease that are identified by echocardiography are missed by careful clinical examination with auscultation, according to findings from population-based studies of schoolchildren in Cambodia and in Mozambique.

Rheumatic heart disease is a major cause of morbidity and mortality in developing nations. Writing in the New England Journal of Medicine for August 2, researchers led by Dr. Eloi Marijon at the Maputo Heart Institute in Mozambique note that it is important to identify affected children, who should undergo primary treatment or secondary prevention.

The studies included randomly selected children ages 6 to 17 years. In Cambodia, clinical examination of 3677 children detected eight cases of rheumatic heart disease. In Mozambique, clinical examination identified five cases in 2170 children screened.

Relying on these results, estimated prevalence rates would be 2.2 cases per 1000 in Cambodia and 2.3 cases per 1000 in Mozambique.

However, echocardiographic screening detected 79 cases in Cambodia and 66 in Mozambique. Corresponding prevalence rates were 21.5 and 30.4 cases per 1000, respectively.

"Prophylactic antibiotic therapy and regular medical surveillance, if adequately administered, may be highly effective in preventing disease progression, even in children with subclinical disease," Dr. Marijon and colleagues maintain.

Patients diagnosed with acute rheumatic fever in both studies were treated with salicylates and antibiotics. Those with rheumatic valve lesions were examined every six months. In cases of lesions "considered to be significant according to World Health Organization criteria," patients were treated with antibiotic prophylaxis and surgical treatment when indicated.

Summing up, the investigators state: "Systematic screening with echocardiography, as compared with clinical screening, reveals a much higher prevalence of rheumatic heart disease (approximately ten times as great)." The findings "have important public health implications.