TB or not TB? Diagnostic Sensitivity, Specifity and Interobserver Agreement in the Radiological Diagnosis of Pulmonary Tuberculosis in Children

Abstract

Background The differentiation between latent tuberculosis infection (LTBI) and tuberculosis (TB) relies on radiological changes. Confirming the diagnosis remains a challenge because typical findings are often missing in children. This study evaluates diagnostic sensitivity, specifity and interobserver agreement on the radiological diagnosis of TB by chest-x-rays in accordance to professional specialization and work experience.

Methods Chest x-rays of 120 children with proven tuberculosis infection were independently evaluated by general radiologists, paediatric radiologists and paediatric pulmonologists. Results were compared to a reference diagnosis created by group of experienced paediatric radiologists and paediatric pulmonologists. Primary endpoints were diagnostic sensitivity and specificity and interobserver variability defined as Krippendorfs alpha of thesel groups compared to the reference diagnosis.

Results Of the 120 chest x-rays 33 (27,5%) were diagnosed as TB by the reference standard . Paediatric pulmonologist had the highest diagnostic sensitivity (90%) but were less specific (71%) whereas general radiologist were less sensitive (68%) but more secific (95%). The best diagnostic accuracy was achieved by pediatric radiologists with a diagnostic sensitivity of 77% and specificity 95% respectively.

Conclusions We demonstrated significant interobserver variability and relevant differences in sensitivity and specificity in the radiological diagnosis of TB between the groups. Paediatric radiologists showed the best diagnostic performance. As the diagnosis of pulmonary TB has significant therapeutic consequences for children they should be routinely involved in the diagnostic process.

Zutsammenfassung

Hintergrund Die Differenzierung zwischen einer Tuberkuloseinfektion (LTBI) und einer pulmonalen Tuberkulose (TB) wird anhand radiologischer Veränderungen im Röntgenbild des Thorax getroffen. Bei Kindern sind diese oft unspezifisch und die Diagnosestellung dadurch erschwert. In dieser Studie werden diagnostische Sensitivität, Spezifität und Intraobserver Variabilität verschiedener Untersucher entsprechend Spezialisierung und Ausbildungsstandes evaluiert.

Methoden Röntgenbilder des Thorax von 120 Kindern mit nachgewiesener Tuberkuloseinfektion wurden unabhängig voneinander von Radiologen, pädiatrischen Pneumologen und pädiatrischen Radiologen im Vergleich zu einer Referenzdiagnose erfahrener pädiatrischer Radiologen und Pneumologen ausgewertet. Die primären Endpunkte Sensitivität, Spezifität und Intraobserver Variabilität wurden nach Krippendorf Alpha errechnet.

Ergebnisse Bei 33 der 120 Röntgenbildern (27,5%) diagnostizierte die Referenzstandardgruppe eine pulmonale Tuberkulose. Die pädiatrischen Pneumologen zeigten eine hohe Sensitivität (90%), aber geringe Spezifität (71%), Radiologen eine niedrigere Sensitivität (68%), aber höhere Spezifität (95%). Die höchste diagnostische Sicherheit bewiesen die pädiatrischen Radiologen mit einer Sensitivität von 77% und Spezifität von 95%.

Zusammenfassung In dieser Studie zeigte sich eine hohe Intraobserver Variabilität sowie Diskrepanzen in Sensitivität und Spezifität zwischen den Gruppen. Bei den pädiatrischen Radiologen lag die Diagnosegenauigkeit am höchsten. Aufgrund der weitreichenden Implikationen einer TB Diagnose sollten diese daher in die Diagnosestellung einbezogen werden.

Key words

children - tuberculosis - radiology - intraobserver variability

Schlüsselwörter

Kinder - Tuberkulose - Radiologie - Interobserver Variabiitätpublished online 2024

Publication History

Article published online:
06 February 2024

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