1) Childhood tuberculosis in IHV-negative patients 

TB in children is usually primary in nature, although it could appear as a generalized disease, affecting any part of the body. Also, under the age of 10 years, children with pulmonary tuberculosis rarely cough up sputum. They usually swallow their sputum. Gastric suction and laryngeal swabs are generally not useful for diagnosis unless facilities are available for M, tuberculosis culture. However, early morning gastric lavage samples may be positive. Hence the diagnosis of TB in children is nearly always presumptive, as is sputum smear-negative pulmonary or extra-pulmonary TB among adults.

The clinical features of TB in children are constitutional and localized in nature (depending on the part of the body affected). The diagnosis is based on clinical features and investigation findings. If available,a tuberculin skin test may be helpful. In most cases, a child with suspected pulmonary TB has usually received treatment with a broad-spectrum antibiotic, without clinical response.

Therefore, one should always look for the following important clues to TB in children:

·       It is often possible to identify the adult source of infection.

·       Constitutional symptoms include low-grade fever, failureto thrive or weight loss (growth faltering). In the case of extra-pulmonary tuberculosis, symptoms will depend on the site of the disease.

·       Tuberculin skin tests are often positive, but not necessarily so.

·       Most chest X-ray findings reveal enlargement of the hilar or mediastinal lymph nodes rather than parenchymal involvement as in adult tuberculosis.

2) HIV-related TB in children

As in adults, the natural history of TB in a child infected with HIV depends on the stage of HIV disease. In the early stage of HIV infection, when immunity is good, the clinical features of TB are similar to those in a child without HIV infection. As HIV infection progresses and immunity declines, dissemination of TB and its occurrence in the form of tuberculous meningitis, miliary tuberculosis, and widespread tuberculous lymphadenopathy become more common.

HIV makes the diagnosis of TB in children even more difficult than usual, for the following reasons:

·       Several HIV-related diseases, including TB, may present in a similar way;

·       The interpretation of tuberculin skin testing is even more unreliable than usual. An immune-compromised child may have a negative tuberculin skin test despite havingTB, and

A child with HIV infection usually comes from a household where one or both parents may have HIV infection. One or both parents may have died from AIDS. Hence, it may be difficult for the child to attend a health facility.