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Radiographic signs and symptoms in children treated for tuberculosis: possible implications for symptom-based
Ben J Marais1, Robert P Gie, Anneke C Hesseling
1Desmond Tutu TB Centre and the Department of Paediatrics and Child Health, Tygerberg Children's Hospital, Stellenbosch University, Cape Town, South Africa. bjmarais@sun.ac.za
Insights
Actively tracing young children exposed to tuberculosis (TB) found most had minimal disease. Symptom screening missed only 9% of intrathoracic TB cases, suggesting potential for improved preventive chemotherapy access.
Area of Science:
- Pediatric infectious diseases
- Public health interventions
- Radiographic diagnostics
Background:
- World Health Organization recommends active contact tracing for children under 5 exposed to sputum smear-positive tuberculosis (TB).
- This study compares radiographic findings in symptomatic children versus actively traced contacts.
Purpose of the Study:
- To compare radiographic disease manifestations in children under 5 treated for TB.
- To evaluate the effectiveness of active tracing versus symptom-based screening in identifying childhood TB.
Main Methods:
- Prospective descriptive study conducted in Cape Town, South Africa (February 2003-October 2004).
- Included 326 children under 5 treated for TB, divided into symptomatic (n=190) and actively traced contacts (n=136).
- Radiographic assessment and categorization of TB (none, intrathoracic, extrathoracic).
Main Results:
- Actively traced contacts were significantly more likely to be "not TB" (OR 7.4) or have primary complex only (OR 26.2).
- Of 326 children, 22% were "not TB", 70% intrathoracic TB, and 8% extrathoracic TB.
- 9% of intrathoracic TB cases (20/230) were asymptomatic, showing primary complex only.
Conclusions:
- Most actively traced child contacts had minimal tuberculosis disease.
- Symptom-based screening would have identified nearly all intrathoracic TB cases.
- Further research needed to assess symptom-based screening for preventive chemotherapy in resource-limited settings.
Background:
The World Health Organization advises active tracing of children younger than 5 years old in household contact with a sputum smear-positive tuberculosis index case. This study compared radiographic disease manifestations in 2 groups of children treated for tuberculosis in an endemic setting: those who presented with suspicious symptoms; and those actively traced as household contacts of an adult index case.
Methods:
We conducted a prospective descriptive study from February 2003 through October 2004 at 5 primary health care clinics in Cape Town South Africa, including all children (younger than 5 years old) treated for tuberculosis (TB).
Results:
A total of 326 children (younger than 5 years old) received antituberculosis treatment; 190 (58.3%) presented with suspicious symptoms, and 136 (41.7%) were actively traced contacts. Children were categorized as; "not TB" 71 (22%), intrathoracic tuberculosis 230 (70%) and extrathoracic tuberculosis 25 (8%). Significantly more actively traced contacts were categorized as "not TB" (odds ratio, 7.4; 95% confidence interval, 3.8-14.3), or demonstrated elements of the primary complex only on the chest radiograph (odds ratio, 26.2; 95% confidence interval, 8.6-89.2), compared with children who presented with suspicious symptoms. Of all children diagnosed with intrathoracic tuberculosis, 20 of 230 (9%) reported no symptoms, all of whom demonstrated elements of the primary complex only.
Conclusions:
The majority of actively traced contacts had minimal disease. Symptom-based screening would have identified all but 9% of children diagnosed with intrathoracic tuberculosis, all of whom demonstrated elements of the primary complex only. Further investigation is required to establish whether symptom-based screening can be justified to improve access to preventive chemotherapy in resource-limited endemic settings.
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