The clinical features and prognostic factors of miliary tuberculosis in a high tuberculosis burden area

Miliary Tuberculosis (TB) remains an important infectious disease that threatens human health. The clinical characteristics and prognostic factors of miliary TB are summarized in this study.

The clinical information of miliary TB patients between 2010 and 2022 was retrospectively analyzed. Patients with miliary TB were characterized and compared to adverse outcomes cases. Factors independently associated with adverse outcomes were determined via multivariate logistic regression analysis.

A total of 288 patients were analyzed, including 181 with adverse outcomes. The clinical manifestations are atypical. 88.54% Of them experienced systemic symptoms, whilst 69.79% manifested respiratory symptoms. 40.97% Presented with neurologic symptoms, while 35.07% reported gastrointestinal symptoms. The major comorbidities were pharmacological immunosuppression (21.53%), pneumoconiosis (15.28%), diabetes (10.76%), and pregnancy or postpartum (7.29%). Regarding microbiology, most patients were diagnosed via sputum or Bronchoalveolar Lavage Fluid (BALF), pleural effusion, ascites, cerebrospinal fluid, urine TB-DNA, and tuberculosis culture. Meanwhile, 2.43% of patients were diagnosed via cerebrospinal fluid NGS. Independent risk factors predictive of adverse outcomes were current smoking, leukocytosis, elevated alanine aminotransferase (ALT) levels, and the combination of lymphopenia with bone marrow tuberculosis or tuberculous lymphadenitis. The accuracy of the model was validated by an area under the ROC curve of 0.753 (95% IC 0.697-0.810).

The clinical manifestations of miliary TB are atypical, and early diagnosis is challenging. The major comorbidities in miliary TB patients were pharmacological immunosuppression, pneumoconiosis, diabetes, pregnancy, and postpartum. Regarding etiological detection, multi-site and multi-type specimens should be collected for a timely diagnosis. Cerebrospinal fluid mNGS test may be a viable choice in some cases. Finally, current smoking, leukocytosis, elevated ALT levels, and the combination of lymphopenia with bone marrow tuberculosis or tuberculous lymphadenitis were identified as independent risk factors for adverse outcomes.