Kunihiko Ito

Cross-sectional studies of tuberculosis prevalence in Cambodia between 2002 and 2011.

OBJECTIVE To measure trends in the pulmonary tuberculosis burden between 2002 and 2011 and to assess the impact of the DOTS (directly observed treatment, short-course) strategy in Cambodia. METHODS Cambodias first population-based nationwide tuberculosis survey, based on multistage cluster sampling, was conducted in 2002. The second tuberculosis survey, encompassing 62 clusters, followed in 2011. Participants aged 15 years or older were screened for active pulmonary tuberculosis with chest radiography and/or for tuberculosis symptoms. For diagnostic confirmation, sputum smear and culture were conducted on those whose screening results were positive. FINDINGS Of the 40,423 eligible subjects, 37,417 (92.6%) participated in the survey; 103 smear-positive cases and 211 smear-negative, culture-positive cases were identified. The weighted prevalences of smear-positive tuberculosis and bacteriologically-positive tuberculosis were 271 (95% confidence interval, CI: 212-348) and 831 (95% CI: 707-977) per 100,000 population, respectively. Tuberculosis prevalence was higher in men than women and increased with age. A 38% decline in smear-positive tuberculosis (P = 0.0085) was observed with respect to the 2002 survey, after participants were matched by demographic and geographical characteristics. The prevalence of symptomatic, smear-positive tuberculosis decreased by 56% (P = 0.001), whereas the prevalence of asymptomatic, smear-positive tuberculosis decreased by only 7% (P = 0.7249). CONCLUSION The tuberculosis burden in Cambodia has declined significantly, most probably because of the decentralization of DOTS to health centres. To further reduce the tuberculosis burden in Cambodia, tuberculosis control should be strengthened and should focus on identifying cases without symptoms and in the middle-aged and elderly population.

Clinical significance of anti-TSH antibody in sera from patients with Graves’ disease and other thyroid disorders

In a survey of patients having anti-TSH antibody (TSH Ab), data from 167 subjects were collected from 8 Japanese Institutions. They were divided into a high TSH Ab group consisting of 63 cases; since the means of assay was via a subnormal thyrotropin binding inhibitor immunoglobulin (TBII) assay, this group had TBII values less than −20%. An additional low TSH Ab group was made up of 104 cases. Out of a total of 11,211 patients, the incidence of TSH Ab for the high and low groups were 0.57% and 13.4%, respectively. More than 95% of these TSH Ab carriers had Graves’ disease or some other autoimmune thyroid disorder, and anti-thyroglobulin and anti-thyroid microsomal antibodies were detected similarly in both groups. It was significant that TSH receptor antibodies could also be detected in both groups, namely, thyroid stimulating antibody and long acting thyroid stimulator (LATS) in 4 of 9 patients in the high TSH Ab group and TBII in 55 of 104 in the low TSH Ab group, respectively. The high TSH Ab levels tended to persist, but 26% of cases showed disappearance or appearance of the antibody during the observation period. In one Graves’ patient, a moderate TBII activity (64.2%) was followed by markedly elevated TSH Ab (TBII: −83.4%) within 2 months. The TSH Ab in the low TSH Ab group disappeared in most cases. Also, fluctuations in TSH Ab did not always parallel those seen for TBII and reciprocal fluctuation pattern (transient or otherwise) were observed in 33%. In conclusion, anti-TSH antibody is produced frequently in patients with either Graves’ disease or some other autoimmune thyroid disorder. Interrelationship between this antibody and the TSH receptor antibody was not evident, and the reason for, and significance of, such antibody production remain to be elucidated.