Objective: To evaluate the value of CT scan for the detection of tuberculous diseases among persons who are suspected to be infected at the contact examination.
Settings: Fukujuji Hospital, Japan.
Method: Retrospective review of the medical records of 22 persons who were normal with plain chest X-ray at an outbreak at a private school, with which total 46 TB cases and 93 infected persons were detected by either symptomatic visits or contact examinations done mainly at public health centers. Among the 44 persons who visited Fukujuji Hospital, 4 persons were symptomatic visits, 3 persons were detected as TB cases by the contact examination at public health centers and 3 persons visited Fukujuji Hospital for the purpose of contact examination before examinations at the public health centers. Eight of these 10 persons were with abnormal chest plain Xray findings and the remaining two persons were normal with plain chest X-ray findings (group A). Among the 34 persons who were referred to Fukujuji Hospital from public health centers as the infected person without diseases, one person showed abnormal chest plain X-ray and 33 persons showed normal chest plain X-ray (group B). Group A persons were examined in June and Group B persons were examined in
Result: The 2 persons in the group A were with abnormal CT findings. They were not diagnosed as TB by the CT findings but followed up after sputum examinations. Both of them were diagnosed as TB by the positive TB culture. Among the 33 persons in the group B, 20 persons were tested with CT scan at the examination done before starting treatment of latent tuberuclous infection and six of these 20 persons were with abnormal findings and were judged as TB diseases.
Discussions: In the case of outbreak with many TB cases and infected persons, CT should be considered for the detection of TB cases among contacts.