[TUBERCULOSIS ANNUAL REPORT 2013--(3) Case Finding and Condition of Tuberculosis on Diagnosis].

Abstract

In 2013, tuberculosis (TB) case findings from the nationwide TB surveillance data in Japan were reviewed with regard to the mode of detection, symptom at diagnosis, diagnostic delay, proportion of far-advanced cavitary lesions, co-existence of human immunodeficiency virus (HIV) infection and diabetes mellitus (DM), and drug susceptibility testing (DST). Among the 20,495 new TB cases in 2013, 83.1% were diagnosed when the patients sought medical attention for TB symptoms or attended medical facilities because of other chief complaints. Among the 15,972 patients with pulmonary TB, 26.4% had only respiratory symptoms, 30.5% had respiratory and non-respiratory symptoms, 17.8% had only non-respiratory symptoms, and 24.5% were asymptomatic. The proportion of patient and doctor delays among the 11,933 symptomatic pulmonary TB cases was analyzed. A large proportion--around 30%--of patients aged 45-54 years with symptomatic pulmonary TB exhibited a patient delay of ≥ 2 months. The proportion of patients with a total delay (i.e., the sum of patient and doctor delays) of ≥ 3 months exhibited a similar tendency to that of those with a patient delay. The proportion of patients aged ≥ 65 years with a doctor delay of ≥ 1 month surpassed that of age-matched patients with a patient delay. Among symptomatic smear-positive TB, a patient delay of ≥ 2 months exhibited a bimodal distribution, and its peak was > 35%. The proportion of patient delay in those aged 30-39 years decreased compared to that of recent years. Meanwhile, the proportion of patients--approximately 15%--with a doctor delay of ≥ 1 month was relatively stable across all the age groups. The proportion of patients with pulmonary TB who had far-advanced cavities in the lungs increased from 1.5% in 1975 to approximately 2% and then remained stable from 1985 to 2013. Among the 50 new TB cases with HIV in 2013, 5 occurred in women and 10 in foreigners. From 2007 to 2013, there were 416 patients with newly diagnosed TB and HIV infections, 359 (86.3%) and 57 (13.7%) of whom were men and women, respectively, including 86 (20.7%) foreigners. The proportions of newly diagnosed TB cases with DM in 2013 were 14.5% (2,964/20,495), of which 16.6% (2,072/12,504) occurred in men and 11.2% (892/7,991) in women. The DST results were obtained through the surveillance system for 7,701 (73.2%) of 10,523 culture-positive pulmonary TB cases in 2013. In previously untreated patients, the proportions of patients with multi-drug resistant TB, any isoniazid resistance, and any rifampicin resistance were 0.4%, 4.5%, and 0.6%, respectively; meanwhile, in previously treated patients, the proportions were 3.7%, 8.0%, and 5.1%, respectively. In previously untreated patients, the proportions of multi-drug resistant TB and any isoniazid resistance decreased comparing with 2012.