A simple ultrasound scan could help doctors detect and monitor a difficult to diagnose form of tuberculosis known as Extrapulmonary Tuberculosis (EPTB) that often goes unnoticed; a new research has shown.

EPTB develops outside the lungs and is frequently diagnosed late because it is harder to confirm using standard laboratory tests. But the study suggests that the ultrasound technique could help bridge this gap, offering a quicker and more accessible way to detect and monitor the disease.

Why it matters

Extrapulmonary TB is often missed or diagnosed late because it does not present with the typical symptoms of lung TB. This delay can lead to severe illness and ongoing transmission.

The findings from this study show that ultrasound—an affordable and widely available tool—could help close this diagnostic gap, especially in settings where laboratory testing is limited. By identifying most cases early, clinicians can start treatment sooner.

Study led by Tanzanian, Swiss scientists

Published in The Ultrasound Journal, the study was led by Ifakara Health Institute scientist Robert Ndege in collaboration with Farida Bani, Omary Ngome, Mohammed Sasamalo, Dorcas Mnzava, Maja Weisser and Martin Rohacek. Additional contributors include Fiona Vanobberghen and Daniel Paris from Swiss TPH.

Ultrasound detects most TB cases, but with limitations

The research tested a specialized ultrasound method known as the extended Focused Assessment with Sonography for HIV-associated TB (eFASH) protocol and analyzed data from 296 adults suspected of having EPTB, of whom 95 were confirmed cases.

Researchers found that the eFASH method correctly identified nearly 94% of confirmed cases, suggesting strong potential as a screening tool.

However, the scan was less accurate at ruling out the disease. In some cases, its ultrasound findings suggested TB even in patients who did not have a confirmed diagnosis, meaning it may produce false positives.

Clinical symptoms remain key in monitoring recovery

Beyond diagnosis, the study also examined whether ultrasound could track how patients respond to treatment. Researchers compared ultrasound results with changes in patients’ clinical signs and symptoms over time.

They found that changes seen on scans did not closely match recovery outcomes. Instead, patients whose symptoms—such as fever, pain or swelling—fully resolved were more likely to recover well.

A complementary tool, not a replacement

The authors stress that while ultrasound is a valuable tool for detecting EPTB, it should not replace clinical judgement which remains essential.

They noted that while the “eFASH approach shows high sensitivity”, its low specificity means it should be used alongside other clinical assessments.

“Ultrasound can be used alongside clinical signs and symptoms to monitor treatment response in patients with EPTB,” they concluded.

Read the publication, here.