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118 Tuberculosis

Risk factors for the development of primary drug resistance include Complications
patient contact with drug-resistant contagious TB, residence in areas Complications of Chest Tuberculosis
with a high prevalence of drug-resistant M. tuberculosis, HIV infection, Complications of chest tuberculosis include:
and the use of intravenous drugs. Secondary drug resistance reflects
noncompliance to the regimen, inappropriate drug regimens, and/or • miliary tuberculosis;
interference with absorption of the drug. • tubercular meningitis;
The current guidelines are that if a child is at risk or has disease
resistant to INH, at least two drugs to which the isolate is sensitive • pleural effusion;
on culture should be administered. Another principle is to never add • pneumothorax;
a single drug to an already failing regimen. The resistance pattern,
toxicities of the drugs, and the patient’s response to treatment should • complete obstruction of a bronchus if caseous material extrudes
determine the duration and regimen selected. into the lumen;
The initial treatment regimen for patients with MDR-TB should • atelectasis;
include four drugs. At least two bactericidal drugs (e.g., INH, rifampin),
pyrazinamide, and either streptomycin or another aminoglycoside (also • bronchiectasis;
bactericidal) or high-dose ethambutol (25 mg/kg/d) also should be • stenosis of the airways;
incorporated into the regimen. • broncho-oesophageal fistula; and
Six-month treatment regimens and intermittent therapy are not
advocated for patients with strains resistant to INH or rifampin. • endobronchial disease.
In isolated INH resistance, the four-drug, 6-month regimen is started Complications of Abdominal Tuberculosis
initially for the treatment of pulmonary TB. INH is discontinued when Complications of abdominal tuberculosis include:
resistance is documented, but pyrazinamide is continued for the entire
6-month course of treatment. • subacute intestinal obstruction;
In the 9-month regimen, INH is discontinued upon the documentation • adhesions;
of isolated INH resistance. If ethambutol was included in the initial
regimen, treatment continues with rifampin and ethambutol for a • intestinal stricture;
minimum of 12 months. If ethambutol was not included, then • malabsorption; and
sensitivity tests are repeated, INH is discontinued, and two new drugs
(e.g., ethambutol and pyrazinamide) are added. • short bowel syndrome.
Resistance to both INH and rifampin is a complicated issue. The Prevention
initial drug regimen is continued (with two drugs to which the organism
is susceptible) until bacteriologic sputum conversion is documented, BCG vaccine is given at birth to all newborns in developing countries
followed by at least 12 months of two-drug therapy. The role of new where tuberculosis is endemic.
agents such as quinolone derivatives and amikacin in MDR cases The best method to prevent cases of paediatric tuberculosis is to find,
remains unclear. diagnose, and treat cases of active tuberculosis among adults. Children
Default from treatment was observed to be a major challenge in the do not usually contract tuberculosis from other children or transmit it
treatment of MDR-TB due to long duration and the expense of ATT. themselves. Adults pass tuberculosis on to children. Improved contact
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investigations and use of directly observed therapy should increase the
Monitoring for Side Effects success rate of finding and treating adult cases of tuberculosis, therefore
Adverse effects of INH (e.g., hepatitis) are rare in children; therefore, reducing the number of cases of paediatric tuberculosis.
routine determination of serum aminotransferase levels is not neces- Mothers infected with tuberculosis (but under regular treatment)
sary. Monthly monitoring of hepatic function tests may be done for should remain away from their babies until their sputum is negative. This
patients with severe or disseminated TB, miliary TB, concurrent or is usually after 2 months of a four-drug regimen given to adults. During
recent hepatic disease, or clinical evidence of hepatotoxic effects, and this period, mothers do not feed their babies directly, but the breast milk
for those receiving high daily doses of INH (10 mg/kg/d) in combina- is expressed and then boiled before being fed to the baby, despite of the
tion with rifampin, pyrazinamide, or both. In the rare case when the fact that this has the risk of destroying the nutrients. The baby is also
patient has symptoms of hepatitis, the regimen is discontinued and given prophylactic INH therapy, 5 mg/kg daily for 6 months. The baby is
liver function is evaluated. If the tests are normal or return to normal, immunised with INH-resistant BCG vaccine soon after birth.
then a decision to restart the medications may be made. The drugs are
reintroduced one by one. Prognosis
Follow-up The prognosis varies according to the clinical manifestation. A poor prog-
nosis is associated with disseminated TB, miliary disease, and tubercular
A regular follow-up every 4–8 weeks is done to ensure compliance
meningitis. Higher mortality rates (20%) occur in children <5 years of age.
and to monitor the adverse effects of and response to the medications
administered. The weight of the child is measured at each visit. The
sclera is examined for any evidence of jaundice.
Follow-up ESR and chest x-ray (CXR) may be obtained after 2–3
months of therapy to observe the response to treatment in patients with
pulmonary TB. However, hilar lymphadenopathy may take several
years to resolve. Thus, a normal CXR is not required for termination
of therapy.