Epidemiology of Culture-Negative Pulmonary Tuberculosis—Alameda County, 2010-2019. Issue 3 (2nd May 2023)

• Record Type: Journal Article
• Authors: Chen, Jennie; Marusinec, Rachel; Brown, Robert; Shiau, Rita; Jaganath, Devan; Chitnis, Amit S.
• Is Part Of: Journal of public health management and practice. Volume 29:Issue 3(2023)
• Page Start: 353
• Page End: 360
• Publication Date: 2023-05-02
• Subjects: epidemiology -- public health -- pulmonary tuberculosis -- sputum/microbiology -- surveillance; Public health administration -- United States -- Periodicals; 253.6
• DOI: 10.1097/PHH.0000000000001715
• Languages: English
• ISSNs: 1078-4659

Abstract

Abstract : Context: Patients with culture-negative pulmonary TB (PTB) can face delays in diagnosis that worsen outcomes and lead to ongoing transmission. An understanding of current trends and characteristics of culture-negative PTB can support earlier detection and access to care. Objective: Describe epidemiology of culture-negative PTB. Design, Setting, Participants: We utilized Alameda County TB surveillance data from 2010 to 2019. Culture-negative PTB cases met clinical but not laboratory criteria for PTB per US National Tuberculosis Surveillance System definitions. We calculated trends in annual incidence and proportion of culture-negative PTB using Poisson and weighted linear regression, respectively. We further compared demographic and clinical characteristics among culture-negative versus culture-positive PTB cases. Results: During 2010-2019, there were 870 cases of PTB, of which 152 (17%) were culture-negative. The incidence of culture-negative PTB declined by 76%, from 1.9/100 000 to 0.46/100 000 ( P for trend <.01), while the incidence of culture-positive PTB reduced by 37% (6.5/100 000 to 4.1/100 000, P for trend =.1). Culture-negative PTB case-patients were more likely than culture-positive PTB case-patients to be younger (7.9% were children <15 years old vs 1.1%; P < .01), recent immigrants within 5 years of arrival (38.2% vs 25.5%; P < .01), and have a TB contact (11.2% vs 2.9%; P < .01). Culture-negative PTB case-patients were less likely than culture-positive PTB case-patients to be evaluated because of TB symptoms (57.2% vs 74.7%; P < .01) or have cavitation on chest imaging (13.1% vs 38.8%; P < .01). At the same time culture-negative PTB case-patients were less likely to die during TB treatment (2.0% vs 9.6%; P < .01). Conclusions: The incidence of culture-negative PTB disproportionately declined compared with culture-positive TB and raises concern for gaps in detection. Expansion of screening programs for recent immigrants and TB contacts and greater recognition of risk factors may increase detection of culture-negative PTB.