تعليقAssessing severity of disease
Access to CXR is an important implementation consideration for assessing the severity of TB disease in children and young adolescents, and is useful in making a decision about the duration of treatment (1). At lower levels of the health care system, access to CXR is often limited or the quality of CXR and the capacity for interpretation may be suboptimal; this can have equity implications, because of the out-of-pocket expenses it might cause. Therefore, the feasibility of CXR varies by setting. It is important to clearly define “non-severe” disease, and NTPs are encouraged to scale up access to quality CXR and train health care providers in its interpretation. If the severity of TB disease in children can be adequately determined under programmatic conditions, then implementation of a 4-month regimen is highly feasible.
The feasibility of assessing the severity of TB disease is a major consideration for implementation, particularly in settings without access to CXR or the capacity for CXR interpretation, and in settings without access to WHO-recommended diagnostic tests. CXR is a critical tool for evaluation of the severity of intrathoracic disease. Extensive or advanced pulmonary TB disease in children aged under 15 years is usually defined by the presence of cavities or bilateral disease on CXR (18). As indicated above, non-severe TB disease refers to peripheral lymph node TB; intrathoracic lymph node TB without airway obstruction; uncomplicated TB pleural effusion; or paucibacillary, non-cavitary disease, confined to one lobe of the lungs, and without a miliary pattern.
Detailed implementation guidance is provided in the operational handbook on the management of TB in children and adolescents (30). The guidance takes into consideration differences in the health care system and country context, including the availability of diagnostic tools for making a diagnosis and assessing disease severity. This guidance includes criteria for assessing disease severity (including clinical criteria in the absence of CXR or rapid diagnostics or other bacteriological tests) to determine eligibility for the shorter regimen.
Continuum between TB infection and disease
The continuum between TB infection and TB disease is an important consideration for implementation. Implementation of the 4-month regimen for the treatment of non-severe TB narrows the differences between recently recommended regimens for TB preventive treatment (TPT) (32) and treatment of non-severe forms of TB disease in children. This is particularly relevant to the TPT regimen that uses 3 months of daily isoniazid and rifampicin (3HR).
Contact investigation
The scale-up of contact investigation approaches is another implementation consideration. The scale-up can improve early case detection of children with non-severe disease who may benefit from the 4-month regimen.
Child-friendly formulations
NTPs are encouraged to prioritize the use of child-friendly FDC formulations for TB treatment in children up to 25 kg body weight; for example, the 3-FDC HRZ 50/75/150 mg (with or without the addition of dispersible ethambutol) and the 2-FDC HR 50/75 mg (20).
Training of health care workers
Another critical factor in successful implementation of the shorter regimen is capacity-building of health care workers at all levels of the health system on diagnostic approaches (including treatment decision algorithms), eligibility for the 4-month regimen and monitoring of children on first-line TB treatment. Training will be necessary when introducing this shorter regimen into a programmatic setting. However, this is a requirement for any new programmatic intervention and the ability to shorten treatment and potentially treat more patients may offset the initial investment in training.