Demographic and microbial characteristics and drug resistance of childhood tuberculosis in Istanbul: analysis of 1,541 cases

Abstract

Introduction: Although tuberculosis (TB) is frequently seen in Turkey, there are limited studies on childhood TB. We aimed to describe clinical and laboratory findings, including drug resistance, of children with TB in Istanbul, Turkey. Methodology: The study included all children aged 0-14 years who were registered in public dispensaries between 2006 and 2010. Results: The study included 1,541 cases. Forty-four percent (n = 763) of the patients were male with a mean age of 8.86±4.19 years. Fiftyfive percent of the patients had pulmonary TB, 39% had extrapulmonary TB, and 6% had both pulmonary and extrapulmonary TB. The most common extrapulmonary involvement sites were the pleura (n = 193), lymph nodes (n = 247), and central nervous system (n = 41). Forty-one percent of the patients were evaluated microbiologically and 35% of them were positive. For the total study group, 14% of them were positive. A drug susceptibility test was performed on 108 patients. Drug resistance to at least one drug was detected in 16% (n = 17), to isoniazid in 15% (n = 16), streptomycin in 12% (n = 12), rifampicin in 9% (n = 10), ethambutol in 7% (n = 8), and multi-drug resistance in 8% (n=9) of patients. Conclusions: This is the largest analysis on demographic features and drug resistance of childhood TB in Turkey. In Turkey, the rate of microbiological diagnosis is low, similar to rates worldwide. More microbiological studies and drug resistance tests should be done and annual changes should be followed with multi-center studies.

Pediatric tuberculosis: A 5-year experience from a Turkish tertiary pediatric hospital

“…Çakır ve ark. (32) (2014) çocuk-larda dirençli TB oranını %48 gibi yüksek bir değer-de saptamışlardır. Çalışmamızda da benzer şekilde kültür pozitif vakaların % 42'sinde ilaç direnci mevcuttu.…”

The Epidemiology of Tuberculosis in Children

“…24 Around one quarter of the disease in children < 5 years, and around 15% of the disease in all children younger than 15 years, is expected to be extrapulmonary. 25 Depending on whether pulmonary/extrapulmonary or intrathoracic/extrathoracic definitions are used, rates of EPTB between 16 and 47% have been reported in various pediatric series; 15,24,[26][27][28] although some series have reported either lower (10%) 14,17,29,30 or higher (>50%) 31,32 proportions of EPTB in children. Lower proportions of EPTB in many series may suggest that cases are missed due to an emphasis on detecting pulmonary disease, whereas very high proportions are often reported in hospital-based series of multidrug-resistant (MDR) TB which is associated with severe referral bias and potentially increased risk of EPTB 27 due to longer durations of being untreated/under-treated.…”

“…27 Interestingly, despite significantly higher incidence and prevalence rates in adult men with TB compared with women, 37 the same gender differences are not seen in children. In most reports, at least half of children with TB are girls, 26,27,29,50,[54][55][56]58,66,67 and in adolescent case series, girls often predominate. Others have reported on the influence of sex on outcomes of infectious diseases from infancy onward, 68 which may be due to physiological or behavioral differences between sexes.…”

“…First, the majority of cases of DR and MDR TB in children are identified in new (previously untreated) cases. 26,31,61,102,103 Second, the drug-susceptibility testing (DST) profile, and spoligotype of M. tuberculosis isolates from children usually match that of adult source cases. 47,62,67 Finally, M. tuberculosis acquires drug resistance through spontaneous gene mutations, and the risk of this is directly proportional to the number of bacilli present.…”

“…42 Based on various pediatric case series, rates of MDR TB of 5% have been detected in most reports from high-income countries. [27][28][29]93,98 Slightly higher rates have been reported from Turkey (8%) 26 and Cape Town (7.1% all children, 10% HIV co-infected children). 16,62 Some of these differences may be related to the populations studied since hospital-based studies are more likely to include children who are more ill or have failed previous treatment.…”