Comparative analysis of clinical manifestations between congenital and non-congenital tuberculosis in infants

To compare the clinical manifestations and associated characteristics of congenital tuberculosis (CTB) and non-congenital tuberculosis (NCTB) in infants, thereby improving early recognition and enabling precision treatment.

A retrospective analysis was conducted of 72 tuberculosis cases in infants aged ≤ 1 year admitted to Kunming Children's Hospital between 2014 and 2024. Given the inherent difficulty in distinguishing congenital from early postnatal acquisition in retrospective studies, patients were classified into a CTB group (n = 23) and an NCTB group (n = 49) using modified Cantwell-based criteria. Differences in perinatal factors, clinical symptoms, laboratory and imaging findings, microbiological/immunological test results, treatment strategies, and outcomes were compared between groups.

The CTB group had a significantly earlier onset of disease (17 days vs. 173 days) and a higher prevalence of prematurity (56.5% vs. 14.3%), cesarean delivery (43.5% vs. 18.4%), and low birth weight (2.33 kg vs. 3.00 kg). No statistically significant differences were observed between groups in fever or cough. However, cyanosis (17.4% vs. 0%), dyspnea (73.9% vs. 40.8%), and jaundice (13.0% vs. 0%) were more frequent in the CTB group. Imaging findings revealed that CTB was more strongly associated with miliary patterns (65.2% vs. 32.7%), pleural effusion (52.2% vs. 20.4%), and hepatosplenic abnormalities (hepatosplenomegaly and nodular hypodense lesions). The CTB group exhibited a more pronounced inflammatory response, with higher WBC/NEU/CRP levels, lower albumin, and elevated bilirubin and urea. Serum IgM and IgA levels were significantly reduced in CTB. The TB-DNA positivity rate was higher in the CTB group (68.2% vs. 41.7%), whereas the IGRA positivity rate was lower (55.0% vs. 89.7%). Compared with NCTB, CTB was associated with substantially higher rates of mechanical ventilation (52.2% vs. 6.1%), ICU admission (56.5% vs. 30.6%), and longer hospitalization (27 days vs. 12 days), as well as a higher incidence of drug-induced liver injury (65.2% vs. 26.5%). No statistically significant differences were found between groups in mortality or treatment discontinuation.

CTB presents earlier in infancy and is characterized by greater dissemination and disease severity, frequently complicated by respiratory-circulatory failure and hepatosplenic involvement. Molecular testing (TB-DNA) is more likely to be positive, whereas immunologic assays (IGRA) are more likely to be negative. However, given the retrospective design and the inherent difficulty in definitively distinguishing congenital from early postnatal infection, these findings should be considered hypothesis-generating. Enhanced screening of high-risk neonates in the perinatal period, combined with molecular diagnostics and multisystem imaging assessment, may facilitate early identification, guide clinical management, and support vigilant monitoring of liver function.

Not applicable.