Diagnostic techniques in paediatric tuberculosis

The Rate of Drug-Resistant Tuberculosis in Korean Children and Adolescents Since 2007

The incidence of drug-resistant tuberculosis (DR-TB) in pediatric populations is a critical indicator of national TB management and treatment strategies. Limited data exist regarding the rate of pediatric DR-TB. In this study, we aimed to analyze the status of DR-TB in Korean children from 2007 to 2013. We analyzed specimens submitted to the Korean Institute of Tuberculosis using Mycobacterium tuberculosis culture and drug susceptibility tests (DSTs) from January 2007 through December 2013. Specimens from patients ≤ 19 years of age were included. Among the 2,690 cases, 297 cases were excluded because of insufficient data, leaving 2,393 cases for the final analysis. In total, resistance to one or more TB drugs was 13.5%. The resistance rates of each of the drugs were as follows: isoniazid (INH) 10.2%, rifampin (RFP) 5.1%, ethambutol (EMB) 3.7%, and pyrazinamide (PZA) 3.1%. The resistance rate of multidrug-resistant TB (MDR-TB) was 4.2%, and that of extensively drug-resistant TB (XDR-TB) was 0.8%. The overall drug resistance rate demonstrated significant increase throughout the study period (P < 0.001) but showed no significant difference compared to previous study from 1999 to 2007. The drug resistance rate of PZA in ≤ 15 years of age group was significantly greater than that of > 15 years (P < 0.001). The drug resistance rate has increased throughout the study period.

CT features of lymphobronchial tuberculosis in children, including complications and associated abnormalities

BACKGROUND

Lymphobronchial tuberculosis (TB) is tuberculous lymphadenopathy involving the airways, which is particularly common in children.

OBJECTIVE

To describe CT findings of lymphobronchial TB in children, the parenchymal complications and associated abnormalities.

MATERIALS AND METHODS

CT scans of children with lymphobronchial TB were reviewed retrospectively. Lymphadenopathy, bronchial narrowing, parenchymal complications and associations were documented.

RESULTS

Infants comprised 51% of patients. The commonest site of lymphadenopathy was the subcarinal mediastinum (97% of patients). Bronchial compression was seen in all children (259 bronchi, of these 28% the bronchus intermedius) with severe or complete stenosis in 23% of affected bronchi. Parenchymal complications were present in 94% of patients, including consolidation (88%), breakdown (42%), air trapping (38%), expansile pneumonia (28%), collapse (17%) and bronchiectasis (9%), all predominantly on the right side (63%). Associated abnormalities included ovoid lesions, miliary nodules, pleural disease and intracavitary bodies.

CONCLUSION

Airway compression was more severe in infants and most commonly involved the bronchus intermedius. Numerous parenchymal complications were documented, all showing right-side predominance.

Risk factors for in-hospital mortality among children with tuberculosis: the 25-year experience in Peru

OBJECTIVE

We examined factors associated with in-hospital death among children with tuberculosis (TB). We hypothesized that a negative response to tuberculin skin testing (TST) would predict decreased survival.

METHODS

This retrospective cohort comprised 2392 children ages 0 to 14 years hospitalized with TB at a Peruvian referral hospital over the 25-year study period. Detailed chart abstraction captured clinical history including TB contacts, physical examination findings, diagnostic data, treatment regimen, and hospitalization outcome. We used Cox proportional hazards regression analyses to determine risk factors for mortality.

RESULTS

Of 2392 children, 2 (0.1%) were known to be HIV-positive, 5 (0.2%) had documented multidrug-resistant TB, and 266 (11%) died. The median time from hospitalization to death was 16 days (interquartile range: 4-44 days). Reaction of <5 mm induration on TST predicted death in a multivariable analysis (hazard ratio [HR]: 3.01; 95% confidence interval [CI]: 2.15-4.21; P < .0001). Younger age, period of admission, alteration of mental status (HR: 3.25; 95% CI: 2.48-4.27; P < .0001), respiratory distress (HR: 1.40; 95% CI: 1.07-1.83; P = .01), peripheral edema (HR: 1.97; 95% CI: 1.42-2.73; P < .0001), and hemoptysis (HR: 0.57; 95% CI: 0.32-1.00; P = .05) were associated with mortality. Treatment regimens that contained rifampicin (HR: 0.47; 95% CI: 0.33-0.68; P < .0001) were associated with improved survival.

CONCLUSIONS

Negative reaction to TST is highly predictive of death among children with active TB. In children with clinical and radiographic findings suggestive of TB, a negative TST should not preclude or delay anti-TB therapy.

[Specific features of tuberculosis in childhood]

Primary infection with Mycobacterium tuberculosis usually occurs during childhood. The source of infection is most often an adult. The risk of infection in exposed children is modulated by various factors related to the infectiousness of the index case, exposure conditions, and the child himself. This review aims to describe the specific diagnostic and therapeutic features of latent TB infection and TB disease in childhood.

Microbiological diagnostic procedures in respiratory infections: mycobacterial infections

This article will review traditional and newer microbiological techniques for the diagnosis of mycobacterial respiratory infections. It will concentrate on the diagnosis of infections due to Mycobacterium tuberculosis, the main mycobacterium causing respiratory infections of clinical and public health importance. The diagnosis of respiratory disease associated with non-tuberculous mycobacteria (NTM), particularly in children with underlying airway pathology such as cystic fibrosis (CF) or bronchiectasis, will be briefly discussed. With respect to the diagnosis of tuberculosis (TB), the review will concentrate on the diagnosis of patients with symptoms and/or signs of clinical disease, rather than the detection of exposure or asymptomatic infection. It will not specifically address the assessment of pre-test probability based on clinical or epidemiological factors, the use of radiological investigations or the investigation of extrathoracic lymph node disease or chest wall disease. The role of newer diagnostic modalities including nucleic acid detection (NAD) and gamma-interferon assays in paediatric practice will be reviewed, and suggestions made as to how they may fit into contemporary diagnostic algorithms.

Recurrent granulomatous tenosynovitis of the wrist and finger caused by Mycobacterium intracellulare: a case report

We report a 65-year-old man with tenosynovitis of the wrist and finger caused by Mycobacterium intracellulare. The diagnosis was made after subsequent recurrence, when a specimen of synovial fluid was subjected to specific polymerase chain reaction and mycobacterial culture. Synovectomy and susceptibility-guided antituberculous therapy permitted complete healing of tenosynovitis.

Community-based therapy for children with multidrug-resistant tuberculosis

OBJECTIVES

The goals were to describe the management of multidrug-resistant tuberculosis among children, to examine the tolerability of second-line antituberculosis agents among children, and to report the outcomes of children treated for multidrug-resistant tuberculosis in poor urban communities in Lima, Peru, a city with high tuberculosis prevalence.

METHODS

A retrospective analysis of data for 38 children <15 years of age with multidrug-resistant tuberculosis, either documented with drug sensitivity testing of the child's tuberculosis isolate or suspected on the basis of the presence of clinical symptoms for a child with a household contact with documented multidrug-resistant tuberculosis, was performed. All 38 children initiated a supervised individualized treatment regimen for multidrug-resistant tuberculosis between July 1999 and July 2003. Each child received 18 to 24 months of therapy with > or =5 first- or second-line drugs to which their Mycobacterium tuberculosis strain was presumed to be sensitive.

RESULTS

Forty-five percent of the children had malnutrition or anemia at the time of diagnosis, 29% had severe radiographic findings (defined as bilateral or cavitary disease), and 13% had extrapulmonary disease. Forty-five percent of the children were hospitalized initially because of the severity of illness. Adverse events were observed for 42% of the children, but no events required suspension of therapy for >5 days. Ninety-five percent of the children (36 of 38 children) achieved cures or probable cures, 1 child (2.5%) died, and 1 child (2.5%) defaulted from therapy.

CONCLUSIONS

Multidrug-resistant tuberculosis disease among children can be treated successfully in resource-poor settings. Treatment is well tolerated by children, and severe adverse events with second-line agents are rare.

Tuberculosis in children: considerations for children from developing countries

Although accurate data are scarce for children, tuberculosis (TB) represents one of the most common infectious causes of morbidity and mortality worldwide. TB case rates have declined among children in the United States in the last decade, but they remain high among children from low-income countries and racial or ethnic minorities. Establishing the definitive diagnosis of TB in a child remains difficult and frequently relies on a constellation of history, clinical findings, and bacteriology. Recently, updated national and international treatment recommendations have been published. Contact investigation and treatment using directly observed therapy are important components of the optimal case detection and management of TB in children.

Epidemiology of childhood tuberculosis in the United States, 1993-2001: the need for continued vigilance

OBJECTIVE

To describe trends and highlight epidemiologic and clinical characteristics of childhood tuberculosis (TB) in the United States.

METHODS

All verified TB cases reported to the national TB surveillance system from 1993 to 2001 were included. A child was defined as a person younger than 15 years.

RESULTS

A total of 11,480 childhood TB cases were reported. Case rates (TB cases/100,000 population) in all children declined from 2.9 (n = 1663) in 1993 to 1.5 (n = 931) in 2001. Among children, those who were younger than 5 years had the highest rate. California, Texas, and New York accounted for 48% of all childhood TB cases. In 2001, TB case rates were higher for foreign-born (12.2) than US-born children (1.1). Hispanic and non-Hispanic black children accounted for nearly three quarters of all cases. Twenty-four percent of children with TB were foreign-born children, with the largest number originating from Mexico (39.8%), the Philippines (8.6%), and Vietnam (5.7%). Most children had evidence of pulmonary TB disease (78.9%). Among culture-positive cases without previous TB, drug resistance to at least isoniazid was 7.3% and to isoniazid and rifampin was 1.6%. In 1999, 82.9% of children received directly observed therapy for at least part of their treatment and 94.8% completed treatment.

CONCLUSIONS

Although the overall TB case number among children is declining in the United States, certain groups of children (eg, younger children, racial and ethnic minorities, foreign-born) are at higher risk for TB. As the United States moves toward the elimination of TB, future efforts should endeavor to prevent all cases of childhood TB.