Imaging recommendations and algorithms for pediatric tuberculosis: part 1-thoracic tuberculosis

Osteoarticular tuberculosis: imaging findings in pediatric patients

Osteoarticular tuberculosis (TB) is an uncommon form of extrapulmonary TB that has the potential to damage joints and bones, generating long-term impairment. Mainly, the initial diagnosis of osteoarticular TB relies on clinical findings and imaging. When required, imaging can aim for less invasive tissue or fluid sampling for pathology, microbiology, and molecular biology analysis. Most TB diagnosis tests have variable and frequently poor sensitivities; however, bone biopsy samples have demonstrated a high percentage of culture positivity. Clinical and imaging findings of osteoarticular TB often mimic other processes, such as rheumatoid arthritis or chronic recurrent multifocal osteomyelitis. When the infection affects the growth plates, angular deformities and extremity length discrepancies can arise. Unfortunately, several osteoarticular TB cases are detected late due to the nonspecific nature of clinical symptoms and non-characteristic imaging findings. This article reviews the most common and atypical osteoarticular TB imaging presentations to increase awareness of osteoarticular TB.

A systematic review and meta-analysis of diagnostic test accuracy of chest ultrasound in diagnosing pediatric pulmonary tuberculosis

INTRODUCTION

Despite medical advancement, pediatric pulmonary tuberculosis (PTB) still has high morbidity and mortality, due to challenging detection in clinical practice. Ultrasound has been touted as the next best diagnostic tool but currently, this claim is unfounded. Therefore, this study aims to systematically review the diagnostic parameters of chest ultrasound in diagnosing pediatric PTB.

METHODS

The literature search started and ended on December 23, 2023. We searched MEDLINE, Cochrane Library, Pubmed, Science Direct, and Google Scholar. Our research question could be formulated as "In pediatric patients who present with signs and symptoms of PTB such as fever, cough, and poor weight gain, how accurate is chest ultrasound in ruling in and ruling out pediatric PTB when the diagnosis is compared to culture, PCR or CXR?" This systematic review adhered to the PRISMA-DTA guidelines while the meta-analysis was conducted with STATA program using the "midas" and "metandi" commands.

RESULTS

There are five studies included with 137 positive PTB children. The combined sensitivity is 84% (95% confidence interval [CI]: 76-89), specificity of 38% (95% CI: 24-54), and summary receiver operating curve yields an area under the curve of 0.83 (95% CI: 0.80-0.86). The I2 value is 24% (95% CI: 0-100) with a p-value of 0.13. The combined negative predictive value is 0.68 (95% CI: 0.58-0.79), and the positive predictive value is 0.57 (95% CI: 0.51-0.63). The positive likelihood ratio is 1 with a 6% increase from the baseline while the negative likelihood ratio is 0.43 with a 12% decrease from the baseline.

CONCLUSION

Chest ultrasound is sensitive but currently could neither exclude nor confirm pediatric PTB.

What is New in the Diagnosis of Childhood Tuberculosis?

The fact that almost half of the 1 million cases of childhood tuberculosis (TB) globally remain undiagnosed jeopardizes the TB elimination goal. Fortunately, there are new advances in this field which have the potential to bridge this diagnostic gap. Advances in imaging include computer assisted interpretation of chest X-rays (CXRs), point of care ultrasound (POCUS) and faster and superior computed tomography/ magnetic resonance imaging (CT/ MRI) protocols. The urine lipoarabinomannan test has proved to be a good point of care test for diagnosing TB in Human immunodeficiency virus (HIV) infected children. Stool and nasopharyngeal aspirates are emerging as acceptable alternatives for gastric lavage and induced sputum for diagnosing intrathoracic tuberculosis. Xpert MTB/RIF Ultra has improved sensitivity compared to Xpert MTB/RIF for diagnosing both pulmonary/ extrapulmonary TB. Xpert XDR is another commercially available accurate point of care test for detecting resistance to drugs other than rifampicin in smear positive samples. Other molecular methods including new line probe assays, pyrosequencing, whole genome sequencing, and targeted next generation sequencing are extremely promising but not available commercially at present. The C-Tb skin test is an acceptable alternative to the tuberculin skin test and interferon gamma release assays for diagnosis of latent infection. There is an urgent need to incorporate some of these advances in the existing diagnostic algorithms of childhood TB.