Limited benefit of CT scans in tuberculosis contact tracing

• Published in: Journal of infection and chemotherapy : official journal of the Japan Society of Chemotherapy Vol. 25; no. 10; pp. 764 - 768
• Main Authors: Yoshiyama, Takashi, Kurosaki, Atsuko, Ogata, Hideo, Sasaki, Yuka, Okumura, Masao
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier Ltd 01.10.2019
• Subjects: Adolescent; Adult; Aged; Aged, 80 and over; Antitubercular Agents - therapeutic use; Child; Contact tracing; Contact Tracing - methods; CT scan; Drug Therapy, Combination - methods; Early Diagnosis; Feasibility Studies; Female; Follow-Up Studies; Humans; Japan - epidemiology; Lung - diagnostic imaging; Male; Middle Aged; Retrospective Studies; Tomography, X-Ray Computed; Tuberculosis; Tuberculosis - diagnosis; Tuberculosis - drug therapy; Tuberculosis - transmission; Young Adult; Japan; Contact tracing; CT scan; Tuberculosis
• ISSN: 1341-321X; 1437-7780
• DOI: 10.1016/j.jiac.2019.03.023

The detection of abnormal findings on computed tomography (CT) scans of tuberculosis contacts combined with normal plain radiographs contributes to the early detection of tuberculosis. However, the benefit of the early detection of abnormalities for the prevention of active tuberculosis during follow-up requires evaluation. We conducted retrospective comparison of the existence of CT scans of tuberculosis contacts without findings of active tuberculosis on plain radiographs at a hospital in Japan. Results: Among 243 contacts without CT scans, five developed tuberculosis during follow-up. Among 229 contacts with CT scans, 24 were judged as targets of multi-drug therapy since their CT findings were suggestive of active tuberculosis at the time of the CT screening. Among 205 contacts judged as having latent tuberculous infection with CT screening, three developed tuberculosis diseases during follow-up. Conclusion: CT scans detected abnormal findings among contacts without abnormalities of plain radiographs but there were some contacts that developed tuberculosis diseases among those with contact investigation including CT scan. The value of CT is equivocal considering the balance of true treatment, overtreatment and harm of radiation.