Diagnosing paediatric TB a major challenge
Although only 6% of tuberculosis (TB) cases reported to the Revised National Tuberculosis Control Programme (RNTCP) are children, experts say that these numbers are highly underreported
Mumbai Although only 6% of tuberculosis (TB) cases reported to the Revised National Tuberculosis Control Programme (RNTCP) are children, experts say that these numbers are highly underreported.
Even today, diagnosing paediatric TB continues to be a major challenge as children struggle to produce sputum- the specimen which allows simple detection of the bacterial infection.
Paediatric specimens also carry a low bacterial load, thus increasing the chances of inconclusive reports. Medical experts are now calling for a wider rollout of ultra-sensitive tests to get conclusive results, as well as the use of newer specimens such as stool samples, which could be easier for children.
According to the World Health Organisation, almost 60% of paediatric TB cases remain undiagnosed. While pulmonary TB, which attacks the lungs, remains a problem, the incidence of extra-pulmonary TB, wherein the bacteria attacks other organs or systems, is also high among children.
“Since getting sputum samples is difficult in children with pulmonary TB, we have to rely on the gastric lavage procedure to extract the samples from their gastric aspirate,” said Dr Vijay Chavan, a chest physician at the Médecins Sans Frontières (MSF) clinic in Govandi. “Since it is an invasive procedure, it is very uncomfortable for the children,” he said.
The lavage procedure involves aspirating liquid from the oesophagus through a tube inserted from the nose or the mouth. When it comes to extrapulmonary TB, doctors have to perform biopsies, which are painful and often not well tolerated by children.
“But since the bacterial load in children is low, we often land up with inconclusive microbiology reports and thus struggle to decide if the case is drug-sensitive or drug-resistant. Very often, children are started on drug-sensitive TB regimens, only to find out later that they were drug-resistant. By then, a lot of crucial time is lost,” said Chavan, adding that the highly sensitive GeneXpert Ultra test should be rolled out widely to tackle paediatric TB better. In Mumbai, the MSF Govandi clinic is among the few centres that use this test.
In its latest guidelines, the WHO has recommended testing stool samples for paediatric patients. While the same GeneXpert machine can be used for stool samples, the procedure of processing the samples is different. In India, some centres are trying out this method as a part of medical research.
“Testing of stool samples has not been endorsed under our TB programme as yet,” said Dr Vikas Oswal, a chest physician at Shatabdi Hospital. “Sample collection is a big challenge among paediatric patients and newer, simpler methods will definitely help,” he said.
Experts said that TB infection is often passed on to children from adults. Yet, there is a lack of awareness about the symptoms among children, and the possibility of prophylaxis treatment, if one person in the family develops the infection.
“Not just adult patients, even doctors treating the adult need to push for screening of the family members including the children,” said Dr Tanu Singhal, a paediatrician and infectious disease expert from Kokilaben Dhirubhai Ambani Hospital.