[Characteristics of pulmonary tuberculosis patients by mode of detection--comparison of patients detected between 1993-94 with those detected between 1986-88].

In a previous study it was concluded that pulmonary tuberculosis (TB) patients who were detected at a hospital, excluding those detected by mass screening (group A), should be classified into three distinct groups. Namely some patients were detected only after the onset of TB symptoms (group B), with the others being treated for other diseases before being diagnosed as having TB (group C). In group C, some patients were detected because of manifesting additional symptoms related to TB such as cough (group C-1), while the remaining patients were detected by chance while being examined for other diseases (group C-2). Four groups respectively had specific characteristics which differentiated each other. The aim of this study is to elucidate changes of proportion and characteristics of group C compared to the former results. Pulmonary TB patients, who were registered between 1993 and 1994, in the area served by Kochi Prefectural Chuo Health Center (N = 332) were compared with those registered between 1986 and 1988 in the area. The results were as follows. 1) The proportion of group C was significantly higher in the period of 1993-94 than during 1986-88. The proportion of elderly people in group C was higher in the period of 1993-1994 than in 1986-88. The proportion of group C is projected to continue increasing as the proportion of elderly among the population increases. 2) The proportion of smear positive cases by sputum was lower in group C-2 than in group B and group C-1. The proportion of either inactive TB or non TB cases was estimated to be higher in group C-2 than in group B and group C-1. 3) In group C-1, the proportion of bacillus positive cases was higher in the period of 1993-94 than 1986-88. The elongation of the interval between the onset of symptoms and diagnosis (total delay) was related to the severity of bacillus finding.