Childhood tuberculosis: treatment strategies and recent advances

Treatment for preventing tuberculosis in children and adolescents: a randomized clinical trial of a 3-month, 12-dose regimen of a combination of rifapentine and isoniazid

IMPORTANCE

Three months of a once-weekly combination of rifapentine and isoniazid for treatment of latent tuberculosis infection is safe and effective for persons 12 years or older. Published data for children are limited.

OBJECTIVES

To compare treatment safety and assess noninferiority treatment effectiveness of combination therapy with rifapentine and isoniazid vs 9 months of isoniazid treatment for latent tuberculosis infection in children.

DESIGN, SETTING, AND PARTICIPANTS

A pediatric cohort nested within a randomized, open-label clinical trial conducted from June 11, 2001, through December 17, 2010, with follow-up through September 5, 2013, in 29 study sites in the United States, Canada, Brazil, Hong Kong (China), and Spain. Participants were children (aged 2-17 years) who were eligible for treatment of latent tuberculosis infection.

INTERVENTIONS

Twelve once-weekly doses of the combination drugs, given with supervision by a health care professional, for 3 months vs 270 daily doses of isoniazid, without supervision by a health care professional, for 9 months.

MAIN OUTCOMES AND MEASURES

We compared rates of treatment discontinuation because of adverse events (AEs), toxicity grades 1 to 4, and deaths from any cause. The equivalence margin for the comparison of AE-related discontinuation rates was 5%. Tuberculosis disease diagnosed within 33 months of enrollment was the main end point for testing effectiveness. The noninferiority margin was 0.75%.

RESULTS

Of 1058 children enrolled, 905 were eligible for evaluation of effectiveness. Of 471 in the combination-therapy group, 415 (88.1%) completed treatment vs 351 of 434 (80.9%) in the isoniazid-only group (P = .003). The 95% CI for the difference in rates of discontinuation attributed to an AE was -2.6 to 0.1, which was within the equivalence range. In the safety population, 3 of 539 participants (0.6%) who took the combination drugs had a grade 3 AE vs 1 of 493 (0.2%) who received isoniazid only. Neither arm had any hepatotoxicity, grade 4 AEs, or treatment-attributed death. None of the 471 in the combination-therapy group developed tuberculosis vs 3 of 434 (cumulative rate, 0.74%) in the isoniazid-only group, for a difference of -0.74% and an upper bound of the 95% CI of the difference of +0.32%, which met the noninferiority criterion.

CONCLUSIONS AND RELEVANCE

Treatment with the combination of rifapentine and isoniazid was as effective as isoniazid-only treatment for the prevention of tuberculosis in children aged 2 to 17 years. The combination-therapy group had a higher treatment completion rate than did the isoniazid-only group and was safe.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT00023452.

Commentary: a targets framework: dismantling the invisibility trap for children with drug-resistant tuberculosis

Tuberculosis (TB) is an airborne infectious disease that is both preventable and curable, yet it kills more than a million people every year. Children are highly vulnerable, but often invisible casualties. Drug-resistant forms of TB are on the rise globally, and children are as vulnerable as adults but less likely to be counted as cases of drug-resistant disease if they become sick. Four factors make children with drug-resistant TB 'invisible': first, the nature of the disease in children; second, deficiencies in existing diagnostic tools; third, overreliance on these tools; and fourth, our collective failure to deploy one effective tool for finding and treating children - contact investigation. We describe a nascent science-advocacy network - the Sentinel Project on Pediatric Drug-Resistant Tuberculosis - whose goal is to end child deaths from this disease. Provisional annual targets, focused on children exposed at home to multidrug-resistant TB, to be updated every year, constitute a framework to focus attention and collective actions at the community, national, and global levels. The targets in two age groups, under 5 and 5-14 years old, tell us the number of: (i) children who require complete evaluation for TB disease and infection; (ii) children who require treatment for TB disease; and (iii) children who would benefit from preventive therapy.

Isoniazid- and streptomycin-resistant miliary tuberculosis complicated by intracranial tuberculoma in a Japanese infant

In Japan, the incidence of severe pediatric tuberculosis (TB) has decreased dramatically in recent years. However, children in Japan can still have considerable opportunities to contract TB infection from adult TB patients living nearby, and infants infected with TB may develop severe disseminated disease. A 3-month-old girl was admitted to our hospital with dyspnea and poor feeding. After admission, miliary TB and multiple brain tuberculomas were diagnosed. Anti-tuberculous therapy was initiated with streptomycin (SM), isoniazid (INH), rifampicin and pyrazinamide. Symptoms persisted after starting the initial treatment and mycobacterial cultures of gastric fluid remained positive. Drug sensitivity testing revealed the TB strain isolated on admission as completely resistant to INH and SM. Treatments with INH and SM were therefore stopped, and treatment with ethambutol and ethionamide was started in addition to rifampicin and pyrazinamide. After this change to the treatment regimen, symptoms and laboratory data gradually improved. The patient was treated with these four drugs for 18 months, and then pyrazinamide was stopped. After another 2 months, ethambutol was stopped. Treatment of tuberculosis was completed in 24 months. No adverse effects of these anti-TB drugs were observed. The patient achieved a full recovery without any sequelae. On the other hand, the infectious source for this patient remained unidentified, despite the extensive contact investigations. The incidence of drug-resistant TB is increasing in many areas of the world. Continuous monitoring for pediatric patients with drug-resistant TB is therefore needed.

Paediatric tuberculosis in a Pacific Islands community in New Zealand

OBJECTIVES

To describe the demographic, clinical and management aspects of an outbreak of tuberculosis (TB) within a paediatric Pacific Island community in Auckland, New Zealand, in 2002-2003.

METHODS

The index and source case are described along with details of the extensive contact tracing that was undertaken in this community.

RESULTS

A total of 24 children were diagnosed with TB over an 11-month period. All cases were found to be epidemiologically linked to the one source case, mother of the index case. This total included 22 children with pulmonary disease, 1 case of miliary disease (index case) and 1 of cervical adenitis. Only 58% had symptoms at diagnosis and only 5 presented to medical attention with symptoms, the remainder had symptoms disclosed after contact tracing occurred. The Mycobacterium tuberculosis isolate was fully sensitive and all children (excluding the child with miliary disease) received short course directly observed therapy. One child developed hepatotoxicity requiring modification of his drug regimen.

CONCLUSIONS

Children are at high risk of developing active disease after exposure to TB. The study describes the minimal symptoms manifested in many of the children with significant radiological changes consistent with pulmonary TB. This highlights the need to consider Mantoux testing and chest X-rays for children presenting with persistent respiratory symptoms in high-risk populations. Issues of contact tracing and adherence were also a problem in this population.

Traitement de la tuberculose

The treatment of tuberculosis in children has evolved towards a short course regimen based on 6 months therapy with isoniazid and rifampin supplemented during the first 2 months with pyrazinamide in the case of pulmonary tuberculosis due to susceptible organisms. In the presence of adult type tuberculosis (upper lobe infiltration and cavitation) or in case of increased risk of drug - resistant organisms, a fourth drug is added initially. Extra pulmonary tuberculosis is generally treated similarly to pulmonary disease, except disseminated disease and meningitis, which are treated during 9 to 12 months. The treatment of children co-infected by HIV is more complex due to increased risk of drug resistant organisms and by interaction between rifampin and anti-retroviral agents. Concerning latent tuberculosis infection, the association of isoniazid and rifampin for 3 months is recommended. The drug treatment of tuberculosis should be integrated in a global approach comprising the detection of new cases, organisation of the treatment and follow up of the child to ensure the completion of treatment.