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F Minagawa

Publications and source records attributed to F Minagawa.

28 records · Page 2Linked to original sources
PubMedDate not supplied

Immuno-epidemiological studies on subclinical infection in leprosy. III. Yearly observations and follow-up studies of schoolchildren by using FLA-ABS and lepromin tests.

The schoolchildren in three regions of Miyako Islands, Okinawa Prefecture, were surveyed annually, from 1978 to 1984, by using the fluorescent leprosy antibody absorption (FLA-ABS) test and the lepromin reaction with the Dharmendra's antigen, for detecting the individuals at high risk of leprosy and for evaluating predictive value of these immunological tests. Constant potency of these tests was confirmed by the percentage of positive reactions among the children in the first grade of elementary schools (5 or 6 years old) surveyed from 1980 to 1984. A temporal rise or drop of the percentages during this period seemed to associate with the yearly reported number of new leprosy cases in each region. Among 1,168 schoolchildren tested with FLA-ABS once or twice or more, the percentage of positive reactions was significantly higher in the children with the enlargement of peripheral nerve without sensory loss than in those without this signs and symptoms. The longer the duration of this signs and symptoms, the higher the percentage of positive FLA-ABS tests. Lepromin test did not show any significant correlation with this signs and symptoms. A concordant persistence or change between the FLA-ABS tests and neural signs or symptoms was observed in 133 out of 331 children examined twice or more. Discordant changes in the remaining were mainly attributed to a conversion to seronegativity before the disappearance of neural signs and symptoms. Changes of FLA-ABS and lepromin reactivities between the initial and final tests suggested a spontaneous cure of subclinical infection with Mycobacterium leprae among the children who were FLA-ABS positive but lepromin negative at the initial test and therefore considered to be a group at high risk of leprosy. Although neural signs and symptoms were found in the majority of these children, none of them so far developed overt symptom of the disease. Based on these findings, predictive value of FLA-ABS test together with lepromin was discussed.

Age Factors↗
PubMedDate not supplied

Immuno-epidemiological studies on subclinical infection in leprosy. I. Clinical and immunological findings in schoolchildren and adults in Okinawa.

For the purpose of understanding subclinical infection with Mycobacterium leprae among the inhabitants in an endemic area, 3,547 schoolchildren and 1,487 adults in several regions of Okinawa were surveyed by using clinical examinations and immunological tests, i.e. the fluorescent leprosy antibody absorption (FLA-ABS) test and the lepromin test using Dharmendra's antigen, during a period from 1978 to 1984. The enlargement of peripheral nerves, especially that of lateral or bilateral auricular and/or ulnar nerves, without loss of sensation was found in 8.4% of the schoolchildren and in 9% of the adults. A frequency of these signs and symptoms was significantly higher in male than in female and tended to increase with age. The percentage of positive reactions in FLA-ABS tests for schoolchildren and adults was 21.8 and 22.5, respectively, the values suggesting a minimum frequency of subclinical infection with M. leprae among these inhabitants. The percentage of positive FLA-ABS tests was significantly higher in those with neural signs and symptoms than in those without. Such a correlation was not found in the lepromin test. Ill-defined depigmentation of the skin without loss of sensation was found in a few percentage of both schoolchildren and adults. However, this sings and symptoms did not correlate with the FLA-ABS test nor with the lepromin test. A history of tuberculin test and BCG vaccination in the schoolchildren seemed to influence the lepromin-reactivity. Among 770 schoolchildren tested with both FLA-ABS and lepromin, 70 (9.1%) were the FLA-ABS positive but lepromin non-positive responders. Neural signs and symptoms were found in 31 of these children.

Adolescent↗
PubMedDate not supplied

Immuno-epidemiological studies on subclinical infection in leprosy, II. Geographical distribution of seropositive responders with special reference to their possible source of infection.

The percentage of positive fluorescent leprosy antibody absorption (FLA-ABS) tests showed significant differences among the inhabitants of different regions in Okinawa. Provided that this percentage indicates the frequency of subclinical leprosy infections, the numbers of inhabitants with subclinical infection per new case with leprosy in the same region ranged from 723 to 3,039. The FLA-ABS test was positive in 16.2% of adults in Minami daito Island where no new case with leprosy was found during the survey for seven years. The differences in the percentages could not be explained by the different prevalence and incidence rates of leprosy in each region nor by the differences in age and sex of the individuals examined. A significant correlation between the FLA-ABS tests and neural signs or symptoms was found in 3 regions. None of adults in Minami daito Island showed such signs or symptoms. The distribution of FLA-ABS positive and negative responders in two hamlets where the incidence of leprosy was relatively high suggested the localization of positive responders surrounding houses in which a leprosy case had recently been found and also the distribution of positive responders in the remote houses. These facts seem to indicate that a possible source of infection to the majority of positive responders might be from the environment rather than from direct contact with leprosy patients.

Adolescent↗
PubMedDate not supplied

[Epidemiological immunological studies on leprosy in Okinawa. 6. Lepromin, lymphocyte transformation, FLA-ABS and leproagglutination tests in the in-and out-patients with leprosy and the relationships among these tests and personal or family history or clinical findings of the patients].

In- and out-patients with leprosy in Okinawa were surveyed by using the following immunological tests: cutaneous reaction to Mitsuda's lepromin (40 million bacilli/ml) (LPR), lymphocyte transformation test with Dharmendara's antigen (DL-LTT), that with phytohemagglutinin (PHA-LTT), fluorescent leprosy antibody absorption test (FLA-ABS) and Leproagglutination test with cardiolipin-lecithin antigen (LAT). A correlation between two tests and a relationship between the test and personal or family history or clinical finding of the patients were evaluated by non-parametric statistics. Spearman's rank correlation coefficient was significant between LPR and DL-LTT, while a reverse correlation was found between LPR and FLA-ABS, DL-LTT and FLA-ABS, and DL-LTT and LAT, respectively. High reactivity in PHA-LTT was found in almost all of patients, irrespective of type and stage of leprosy, suggesting general immune responsiveness of leprosy patients in Okinawa. The other tests showed a significant difference in the mean rank of reaction values according to clinical findings such as type and stage of leprosy, property of skin lesion, loss of eyebrow, and bacteriological test. The use of LPR and DL-LTT for the study of cell-mediated immunity in leprosy was therefore confirmed. FLA-ABS was found useful for early serodiagnosis, while LAT for the study of autoimmunity in leprosy. None of these immunological tests showed significant difference among the subgroups of patients classified by the following items: presence or absence of consanguineous patient with leprosy, living place, place of onset, presence or absence of neural symptoms such as the enlargement of peripheral nerve, claw hand and facial palsy, ocular and nasal involvement, ENL in lepromatous and borderline leprosy and conditions in the treatment. On the other hand, LPR showed higher reactivity in female than in male, in the patients at home than those discharged, and in the patients with drop foot than those without. Higher reactivity of DL-LTT was also found in male than in female and in the patients with plantar ulcer than those without. FLA-ABS reactivity was significantly higher in the discharged patients than the inpatients, in the period of 5 to 9 years after onset than that of 20 or more years, but the reactivity was lower in the patients with drop foot than those without. LAT reactivity was significantly higher in the 30-39 years old patients than 0-19 years old, and in the patients with physical work than those with mental.(ABSTRACT TRUNCATED AT 400 WORDS)

Adolescent↗