Hanseníase: Resumos Hanseniasis Abstracts Bacteriologia, Imunologia Bacteriology, Immunology

The fluorescent leprosy antibody absorption (FLA-ABS) test was used for detecting subclinical leprosy infection in the inhabitants in the Miyako Islands which were known as leprosy hyperendemic areas in Japan. One hundred and twenty-six of 1,559 schoolchildren and 68 of 571 adults had suspicious neural symptoms such as the enlargement of auricular and/or ulnar nerve(s) without sensory loss. The FLA-ABS test was positive in 90(71.4%) of 126 schoolchildren with the enlargement of peripheral nerve and in 13 (14.1%) of 92 children without any clinical signs. In adults, similar percentages, 66.2% (45/68) and 16.9%(23/136) were obtained. Therefore, a correlation between the FLAABS test and the neural symptom is significant statistically in both schoolchildren and adults. Serological specificity of these positive reactions was checked by testing for crossreactivity with the other mycobacteria. Only 16 out of 183 positive sera showed some cross-reactions. After additional absorption of the sera with the cross-reacting bacteria, positive reactions against M. leprae were not affected at all. On the other hand, the FLAABS test was negative in all of the healthy blood donors and the students of nurse school and in 23 of 24 patients with the other skin diseases in leprosy nonendemic areas. Therefore, the percentage of positive FLAABS test is considered to represent the rate of subclinical leprosy infection. The lepromin test with the Dharmendra's antigen was conducted on the schoolchildren for selecting the individuals with low or no resistance against leprosy. Among 217 schoolchildren examined simultaneously with this and FLAABS test and the neural sympton is signifreactions. The enlargement of peripheral nerve was found in 36 of these cases. The other 30 children showed positive FLA-ABS test, while negative or doubtful Fernandez' reaction. The neural symptom was found in a half number of these cases. It was suggested that these children should receive priority to vaccination for the prophylaxis of leprosy. — Authors' summary