Feedback
In children and adolescents, severity of TB disease ranges from mild to severe. Children with nonsevere, drug-susceptible TB are now eligible to receive a shortened 4-month treatment regimen. For consideration of a 4-month treatment regimen for non-severe, drug-susceptible PTB in children and young adolescents aged 3 months to 16 years, non-severe TB is defined based on the clinical presentation of disease as assessed through physical examination and CXR.
EPTB refers to any bacteriologically confirmed or clinically diagnosed case of TB involving organs other than the lungs (e.g. pleura, peripheral lymph nodes, abdomen, genitourinary tract, skin, joints and bones, meninges) (71). The classification of intrathoracic lymphadenopathy in children was updated following an expert consultation in September 2021 as PTB. EPTB is common in young children and in children and adolescents living with HIV.
In children with presumptive PTB attending health care facilities, integrated treatment decision algorithms may be used to diagnose PTB. This is an interim conditional recommendation valid until 2024, after which new evidence will be reviewed (see Box 4.6).
Routine HIV testing should be offered to all children and adolescents completing evaluation for exposure to TB, with presumptive TB or diagnosed with TB. Early and accurate detection of HIV infection is important to support the integrated management of TB/HIV coinfection. All children and adolescents with HIV-associated TB are eligible for ART and co-trimoxazole prophylaxis (6, 78).
CXR remains an important tool in the diagnosis of TB in children, especially those with negative bacteriological tests or where bacteriological testing is not available or not feasible. Most children with PTB have radiographic changes suggestive of TB. If possible, anteroposterior and lateral films should be obtained in children aged under 5 years, and posteroanterior films in older children and adolescents.
Abnormalities on CXR suggestive of PTB include:
Testing for M. tuberculosis infection using TST or IGRA is useful to support a diagnosis of TB in children with suggestive clinical features who are sputum smear-negative or who cannot produce sputum. A positive test for TB infection indicates prior or current infection with M. tuberculosis and can be particularly useful in the absence of known TB exposure (no positive contact history), as it confirms the child has been infected at some point in time (6, 15).
TST is considered positive (indicating infection with M. tuberculosis) if:
In children with signs and symptoms of PTB in settings with a pre-test probability of 5% or higher (prevalence of confirmed TB of 5% or above in this specific population), repeat testing with Xpert MTB/RIF or Ultra may be considered after an initial negative Xpert MTB/RIF or Ultra test if the clinician has a high index of suspicion that the child has TB, using any of the recommended specimen types.
The urine lateral flow lipoarabinomannan (LF-LAM) assay is an immunocapture assay based on the detection of the mycobacterial lipoarabinomannan antigen in urine. For specific populations, LF-LAM may be used together with other approved TB diagnostics tests and affords a distinct advantage as a point-of-care test. Although the assay lacks sensitivity, it can be used as a fast bedside rule-in test for people living with HIV, especially in urgent cases where a rapid TB diagnosis is critical for the person’s survival.
The Xpert MTB/RIF assay is a cartridge-based automated test that uses real-time polymerase chain reaction (PCR) on the GeneXpert® platform to identify M. tuberculosis complex and mutations associated with rifampicin resistance directly from sputum specimens in less than 2 hours (76).
The Xpert MTB/RIF Ultra assay uses the same GeneXpert platform and a new enhanced cartridge developed to improve the sensitivity and reliability of detection of M. tuberculosis complex and rifampicin resistance (76).
Depending on the availability, resources and capacity, appropriate specimens from suspected sites of involvement should be collected for rapid testing using mWRDs or culture, and histopathological examination should be done for children with EPTB whenever possible. WHO recommends that NTPs replace microscopy as the initial diagnostic test for TB with mWRDs, which can be used on various respiratory and non-respiratory specimens (Table 4.4) (76).