Childhood cancers often misdiagnosed as TB, leads to more deaths

Cancer is frequently misdiagnosed as tuberculosis (TB) in children due to the clinical and radiologic overlap of the two diseases, which then contributes to increased mortality in this population, reveals a recent study.

A retrospective study was conducted to examine TB diagnoses in children with cancer registered in the Tygerberg Hospital Childhood Tumor Registry from 2008 to 2018. The authors assessed patients on anti-TB treatment (ATT) at cancer diagnosis or diagnosed with TB within 1 month of cancer diagnosis. They then described the circumstances and extent of misdiagnosis, quantified the delay in therapy, and documented the outcomes of these patients.

A total of 539 children were identified in the registry, of whom 27 (5 percent) initiated ATT prior to cancer diagnosis. Both pulmonary and extrapulmonary TB complicated the cancer diagnosis.

Twenty-two (81 percent) of the 27 children on ATT at cancer diagnosis had contact with a TB case. A positive tuberculin skin test was noted in six of 12 children (50 percent). At cancer diagnosis, 16 children (59 percent) had chest radiograph changes interpreted as TB, with 11 (41 percent) deemed as suggestive of TB upon review by an expert. The median diagnostic delay between TB and cancer diagnoses was 25 days (interquartile range, 3.5–58).

Additionally, 204 (38 percent) of the 539 children with cancer died, including 18 out of 30 (60 percent) on ATT at cancer diagnosis or diagnosed with TB within a month of cancer diagnosis (odds ratio, 2.6, 95 percent confidence interval, 1.2–5.4; p=0.012).

“TB and childhood cancers have overlapping presentations, and malignancies may be misdiagnosed as TB in high TB-burden settings,” the authors said.