There were 272 women referred to the San Diego County Tuberculosis Control office because of a positive chest roentgenogram or a positive TBN-ST or a history of one. Only 39 called to make an initial appointment, 32 of whom had charts available for review. All but two of these women were lost to follow-up before completing a six-month course of isoniazid.
None of the women in our study population was subsequently reported to the San Diego County Tuberculosis Control office as having the diagnosis of active tuberculosis. One child born during the study period developed tuberculous meningitis at the age of eight months. Her mother left the hospital before her TBN-ST could be read so she had been excluded from the study. Subsequent investigation revealed that a family friend was the index case.
Analysis of Tuberculin Skin Test Results
In order to determine the sensitivity of the Rapid Tuberculosis Screening TBN-ST method, it would have been necessary to perform an additional reading at 48- to 72-h for each patient. Because this was not feasible, we derived two estimates of the sensitivity of our method. The following calculations assume a negligible false-positive rate. The validity of this assumption will be examined in the “Discussion.”