Abdominal lymphadenopathy in children with tuberculosis presenting with respiratory symptoms

Abstract

Diagnosis of pulmonary tuberculosis (PTB) in children is challenging and radiographs are often normal or non-specific. Access to the chest using ultrasound is difficult, but access to the abdomen is simple and carries no radiation burden. Diagnosis of PTB using abdominal lymphadenopathy as a surrogate for mediastinal lymphadenopathy may present a simple and accurate additional diagnostic technique that is of value in developing countries. We determined the prevalence of abdominal lymphadenopathy in paediatric patients with confirmed TB presenting with respiratory symptoms. Chest radiographs and abdominal ultrasounds of 47 children with confirmed TB and respiratory symptoms were reviewed. The prevalence of abdominal TB was determined and comparisons made between thoracic and abdominal lymphadenopathy to determine the relative value of ultrasound. On ultrasound, the prevalence of abdominal lymphadenopathy was 19% and solid organ involvement was found in 23% of patients. Some 70% of children had thoracic lymphadenopathy on chest radiography, with 89% of patients having evidence of PTB. If chest radiography were to be considered the radiological reference standard, abdominal ultrasonography had a sensitivity of 18% (95% CI 7.0–35.5%) with a specificity of 79% (95% CI 49.2–95.1%) for thoracic lymphadenopathy. Ultrasound and chest radiography in combination detected a total of 36 patients with lymphadenopathy, with a 6% improvement in the rate of lymphadenopathy detection; however, this was not statistically significant. The prevalence of abdominal TB of 23% is noteworthy. We suggest that abdominal ultrasound has a definitive adjunctive role in investigating children with suspected TB.