Diagnostic Performance of Comprehensive Point-of-Care Ultrasound for Pediatric Tuberculosis in Spain: A Prospective Observational Study

Background Diagnosing tuberculosis (TB) in children is challenging because of nonspecific symptoms, low microbiological yield, and imaging limitations. Comprehensive point-of-care ultrasound (cPOCUS) may detect mediastinal lymphadenopathy, but evidence remains limited. Methods We conducted a prospective observational study in four tertiary hospitals in Spain (May 2023-June 2024) enrolling children (0-18 years) with presumptive TB. All participants underwent chest X-ray (CXR) and cPOCUS; chest CT was performed when clinically indicated. cPOCUS assessed lung, mediastinal, and abdominal compartments using a standardized protocol. Images were independently reviewed by expert readers blinded to clinical data. Diagnostic performance was evaluated against a final TB classification based on clinical, immunological, microbiological, and conventional radiological findings, excluding cPOCUS. Results Twenty-seven children were included (median age 9.0 years), of whom 12 (44.4%) had TB disease. CT was performed in 14 (51.9%). Only 22.2% of cPOCUS examinations were complete. Mediastinal lymphadenopathy was the most frequent abnormality. cPOCUS detected abnormalities in 58.3%-63.6% of TB cases, particularly aortopulmonary window lymph nodes and small subpleural consolidations, with moderate sensitivity and high specificity (80.0%-86.7%). Inter-reader agreement was high (κ = 0.92). Conclusions In this pilot prospective study, cPOCUS demonstrated limited diagnostic performance but high inter-reader reliability. These exploratory findings suggest that cPOCUS may complement standard imaging for selected abnormalities (particularly aortopulmonary window lymphadenopathy), but larger studies with optimized protocols are needed before broader clinical implementation.