With the ongoing pandemic of SARS Covid-19, let's not ignore the more notorious tuberculosis (TB). It is caused by bacteria called tubercle bacilli and usually infects the lungs. But other organs such as the spine, brain, intestines, and kidney may also be involved albeit much less frequently. TB spreads usually by droplets or air coughed by infected people. A child can acquire an infection but remain latent until another sickness makes way for it to manifest.
Tuberculosis can occur in three stages:
Exposure: This occurs when a child comes in contact with a person having TB. The child will also test negative for all investigations.
Latent TB infection: This occurs when a child has TB bacteria but is asymptomatic. The infected child’s immune system inactivates the TB bacteria and will remain latent inside their bodies for the rest of his life. This child would have a positive skin test but a normal chest X-ray. They fortunately don't spread the disease.
TB disease: This is when a child has signs and symptoms of an active infection and will test positive for tests. They can also spread the disease if untreated.
Which children are at risk for TB?
TB usually targets children with a weak immune system. This includes children who have chronic ailments, poorly nourished (both over and undernutrition), on immunosuppression treatment, HIV, diabetes and so on. Younger children are more likely to have TB spread through their bloodstream and cause complications, such as meningitis i.e. brain infection.
What are the symptoms of TB in a child?
The most common symptoms of active TB in younger children include fever, weight loss, poor appetite and growth, cough and swollen glands. Adolescents may have a cough that lasts longer than two weeks, chest pain, blood in sputum, fatigue, loss of weight and appetite, fever with chills. The symptoms of TB can mimic other health conditions or may even pretend to be a milder disease.
How is TB diagnosed in a child?
The prolonged symptoms mentioned above will give a clue to your doctor. Proper family history and contact history of the child can never be overemphasised. The doctor will also examine the child's lungs, stomach, glands, etc to look for any tell-tale signs. Further, he or she may order a skin test where a small amount of testing material is injected into the top layer of the skin. If a certain size swelling develops within two or three days at the site of injection, the test may be positive for TB infection.
The doctor may also order a chest X-ray and sputum test for microscopy and culture of the organism. Younger children who aren't capable of collecting sputum may require admission for the collection of stomach fluids to detect the bacilli from the swallowed sputum by the child.
A newer test called Gene Xpert is now readily available. This test is more sensitive and even gives faster results which help to initiate specific treatment quickly. It may also tell about the resistance offered by the organism to the planned treatment. Molecular techniques to detect TB are in the research phase and we hope they will make the diagnosis faster and more reliable.
How is TB treated in a child?
For latent TB, the child is given a six to 12-month course of the medicine isoniazid. For active TB, a child will require to complete a four-medicine course, for six months or more, depending on the response to treatment. Compliance with treatment is of paramount importance to kill sufficient bacilli from the body but research says that the last bacillus is never really killed. Children usually show signs of improvement within a few weeks of starting treatment.
After two weeks of treatment with medicine, a child is usually not contagious. These medicines cause side effects, most of them minor but a few severe. The side effects can be mitigated by regularly monitoring liver and kidney function, hearing and vision and other tests as advised by health care providers.
(Dr Fazal Nabi is the director of paediatrics at Jaslok Hospital and Research Centre, Mumbai. Views are personal)