A fourth study of case-finding methods for pulmonary tuberculosis in Kenya

Abstract
This investigation is the fourth of a series of case-finding studies in Kenya. It explored in a new area (the Baragwi location of Kirinyaga), five methods of case-finding involving the examination of the sputum by smear and culture of symptomatic tuberculosis suspects in the community identified (i) by interrogation of the Elders, (ii) by interrogation of household heads, (iii) by tracing all patients registered during the previous 10 years in the District Tuberculosis Register, (iv) by the examination of all their close contacts and (v) from outpatients attending peripheral health units. The initial interrogation of the Elders yielded 123 suspects with bacteriological results, of whom seven were culture-positive, including four smear-positive. A second interrogation three to six months later produced a further 66 suspects and four more culture-positive cases (all smear-negative). The examination of a second sputum specimen after three to six months from all the suspects from both interrogations produced a further culture-positive smear-negative case. A single interrogation of household heads in a house-to-house survey yielded 867 suspects and 15 culture-positive cases, including eight smear-positive. Of 862 suspects with no history of tuberculosis, 778 (90%) claimed they had attended a medical facility for their respiratory symptoms during the previous year, the most recent visit being within the previous month in 24%. All except 1% of the total had attended on more than one occasion, the average number of attendances being 5·3. 83% said they had attended the peripheral health units and 37% had attended the Central District Hospital, yet 65% of the suspects had had neither a chest radiograph nor their sputum examined bacteriologically. Of the 114 cases of tuberculosis registered in the District Tuberculosis Register during the previous 10 years, nine were currently culture-positive, seven being smear-positive. The examination of a second sputum specimen from 105 yielded one more culture-positive case. Of 577 household contacts of the registered cases, seven were culture-positive, three being smear-positive. The examination of a second sputum specimen from 568 yielded two more culture-positive cases. During a full year, only 45 suspects were registered among out-patients attending seven health units serving the area (population 27,500), of whom four were smear-positive. This indicates a failure of the staff to take appropriate actions.