Drug-resistant tuberculosis: pediatric guidelines

Drug-resistant tuberculosis and advances in the treatment of childhood tuberculosis

Over the last 10 years, interest in pediatric tuberculosis (TB) has increased dramatically, together with increased funding and research. We have a better understanding of the burden of childhood TB as well as a better idea of how to diagnose it. Our appreciation of pathophysiology is improved and with it investigators are beginning to consider pediatric TB as a heterogeneous entity, with different types and severity of disease being treated in different ways. There have been advances in how to treat both TB infection and TB disease caused by both drug-susceptible as well as drug-resistant organisms. Two completely novel drugs, bedaquiline and delamanid, have been developed, in addition to the use of older drugs that have been re-purposed. New regimens are being evaluated that have the potential to shorten treatment. Many of these drugs and regimens have first been investigated in adults with children an afterthought, but increasingly children are being considered at the outset and, in some instances studies are only conducted in children where pediatric-specific issues exist.

Infectious Diseases of Poverty in Children: A Tale of Two Worlds

"Infectious diseases of poverty" (IDoP) describes infectious diseases that are more prevalent among poor and vulnerable populations, namely human immunodeficiency virus (HIV) infection, tuberculosis (TB), malaria, and neglected tropical diseases (NTDs). In 2013, 190,000 children died of HIV-related causes and there were 550,000 cases and 80,000 TB deaths in children. Children under age 5 account for 78% of malaria deaths annually. NTDs remain a public health challenge in low- and middle-income countries. This article provides an overview of the major IDoP that affect children. Clinicians must be familiar with the epidemiology and clinical manifestations to ensure prompt diagnosis and treatment.

Recommendations for treating children with drug-resistant tuberculosis

Tuberculosis (TB) is still one of the most difficult infectious diseases to treat, and the second most frequent cause of death due to infectious disease throughout the world. The number of cases of multidrug-resistant (MDR-TB) and extensively drug-resistant TB (XDR-TB), which are characterised by high mortality rates, is increasing. The therapeutic management of children with MDR- and XDR-TB is complicated by a lack of knowledge, and the fact that many potentially useful drugs are not registered for pediatric use and there are no formulations suitable for children in the first years of life. Furthermore, most of the available drugs are burdened by major adverse events that need to be taken into account, particularly in the case of prolonged therapy. This document describes the recommendations of a group of scientific societies on the therapeutic approach to pediatric MDR- and XDR-TB. On the basis of a systematic literature review and their personal clinical experience, the experts recommend that children with active TB caused by a drug-resistant strain of Mycobacterium tuberculosis should always be referred to a specialised centre because of the complexity of patient management, the paucity of pediatric data, and the high incidence of adverse events due to second-line anti-TB treatment.

How to manage children who have come into contact with patients affected by tuberculosis

Childhood tuberculosis (TB) indicates a recent infection, particularly in children aged < 5 years, and therefore is considered a sentinel event insofar as it highlights the presence of an undiagnosed or untreated source case. The risk of acquiring TB is directly proportional to the number of bacilli to which a subject is exposed and the environment in which the contact occurred. This document contains the recommendations of a group of Italian scientific societies for managing a child exposed to a case of TB based on an analysis of the risk factors for acquiring latent tuberculous infection (LTBI) and developing the disease, and the particular aspects TB transmission during the first years of life. The guidance includes a detailed description of the methods used to identify the index case, the tests that the exposed child should receive and the possibilities of preventive chemoprophylaxis depending on the patient's age and immune status, the chemotherapy and monitoring methods indicated in the case of LTBI, the management of a child who has come into contact with a case of multidrug-resistant or extensively drug-resistant TB, and the use of molecular typing in the analysis of epidemics. The group of experts identified risk factors for tuberculous infection and disease in pediatric age as well as gave recommendation on management of contacts of cases of TB according to their age, risk factors and exposure to multidrug-resistant or extensively drug-resistant TB.

Why do child contacts of multidrug-resistant tuberculosis not come to the assessment clinic?

BACKGROUND

Local policy advises that children exposed to multidrug-resistant tuberculosis (MDR-TB) should be assessed in a specialist clinic. Many children, however, are not brought for assessment.

METHODS

Focus group discussion was used to design appropriate questionnaires. From 1 September 2011, the first 50 children referred to the specialist paediatric MDR-TB clinic, Cape Town, South Africa, and who attended their clinic appointment, were recruited. The first 50 children who were referred but who did not attend were concurrently identified, traced and recruited. Differences in group characteristics were compared.

RESULTS

The median age of the children was 35 months: 48 (48%) were boys, 4 (4%) were human immunodeficiency virus infected and 47 (47%) were of coloured ethnicity. Factors significantly associated with non-attendance at the MDR-TB clinic were: Coloured ethnicity (OR 2.82, 95%CI 1.21-6.59, P = 0.01), the mother being the source case (OR 3.78, 95%CI 1.29-11.1, P = 0.02), having a smoker resident in the house (OR 2.37, 95%CI 1.01-5.57, P = 0.04), the time (P = 0.002) and cost (P = 0.03) required to get to the specialist clinic, and fear of infection whilst waiting to be seen (OR 2.45, 95%CI 1.07-5.60, P = 0.03).

CONCLUSIONS

Reasons for non-attendance at paediatric MDR-TB clinic appointments are complex and are influenced by demographic, social, logistical and cultural factors.

Epidemiology and clinical management of tuberculosis in children in Canada

Although often regarded as a foreign disease, latent tuberculosis or tuberculosis disease will be encountered in many clinical situations by the Canadian child health practitioner. There are key differences between tuberculosis in children and adults. In the present article, the changing epidemiology of tuberculosis in children in Canada and around the world, the pathogenesis of infection, diagnostic tests, and clinical management of childhood latent tuberculosis and tuberculosis disease are reviewed.

Treatment of multidrug-resistant and extensively drug-resistant tuberculosis in adolescent patients

The authors describe 2 pediatric patients with drug-resistant tuberculosis in whom new diagnostic and therapeutic approaches were crucial to good clinical evolution. Although there was good clinical outcome, important side effects with linezolid and amikacin occurred, namely medullary hypoplasia and neurosensorial hypoacusia, respectively. A multidisciplinary approach with close follow up was of major importance in managing these patients.

Moxifloxacin for the treatment of pulmonary tuberculosis in children: a single center experience

OBJECTIVE

To report our experience on the safety and tolerability of moxifloxacin for treating children affected by pulmonary TB.

STUDY DESIGN

Children receiving a moxifloxacin-containing anti-TB regimen were included in the study. Their medical records were revised at the end of follow-up.

METHODS

We describe nine children treated with moxifloxacin for pulmonary TB at Regina Margherita Children's Hospital (Turin, Italy) between 2007 and 2012. Moxifloxacin was administered orally at 10 mg/kg/day once daily (maximum dose = 400 mg/day) following World Health Organization indications. During treatment, patients were systematically assessed for the development of side effects.

RESULTS

Eight children were considered cured at the end of treatment; one child was lost to follow-up after 3 months of treatment. Two children had side effects during treatment: one developed arthritis of the ankle; the other had liver toxicity, whose relationship with moxifloxacin could not be ruled out. We did not observe any case of QT prolongation, central nervous system disorders, growth defects or gastrointestinal disturbances.

CONCLUSIONS

A moxifloxacin-containing regimen might be considered for the treatment of TB in children, especially for drug-resistant and extensive forms. However, vigilance for possible side effects is recommended, especially if other drugs are concomitantly used. Studies on wider populations are needed to better define the impact of long-term treatments with quinolones on children's growth and psychomotor development and to outline regulatory indications on moxifloxacin use in the pediatric setting.

Management of patients with multidrug-resistant/extensively drug-resistant tuberculosis in Europe: a TBNET consensus statement

The emergence of multidrug-resistant (MDR) and extensively drug-resistant (XDR) tuberculosis (TB) substantially challenges TB control, especially in the European Region of the World Health Organization, where the highest prevalence of MDR/XDR cases is reported. The current management of patients with MDR/XDR-TB is extremely complex for medical, social and public health systems. The treatment with currently available anti-TB therapies to achieve relapse-free cure is long and undermined by a high frequency of adverse drug events, suboptimal treatment adherence, high costs and low treatment success rates. Availability of optimal management for patients with MDR/XDR-TB is limited even in the European Region. In the absence of a preventive vaccine, more effective diagnostic tools and novel therapeutic interventions the control of MDR/XDR-TB will be extremely difficult. Despite recent scientific advances in MDR/XDR-TB care, decisions for the management of patients with MDR/XDR-TB and their contacts often rely on expert opinions, rather than on clinical evidence.

This document summarises the current knowledge on the prevention, diagnosis and treatment of adults and children with MDR/XDR-TB and their contacts, and provides expert consensus recommendations on questions where scientific evidence is still lacking.

TBNET consensus statement on the management of patients with MDR/XDR-TB has been released in theEur Respir Jhttp://ow.ly/uizRD

Bakterielle Infektionen: Atypische Bakterien

Chlamydophila (früher Chlamydia) pneumoniae ist im Kindesalter ein seltener Erreger respiratorischer Infektionen, vor allem der Pneumonie, wenn die PCR als direkte Nachweismethode herangezogen wird. Die höhere Nachweisrate von Antikörpern gegen C. pneumoniae deutet auf eine hohe Rate asymptomatischer oder unspezifischer Infektionen durch C. pneumoniae hin.

Der Mensch ist weltweit das einzige Erregerreservoir. Kranke, seltener auch asymptomatische Ausscheider (Wochen bis 1 Jahr) sind die Ansteckungsquelle. Die Übertragung erfolgt als „Tröpfcheninfektion“ mit respiratorischen Sekreten. Eine epidemische Krankheitshäufung ist beschrieben. In feuchtem Milieu können Chlamydien bis zu 30 h auf unbelebtem Material überleben.

Im Erwachsenenalter haben 50–75 % der Bevölkerung Antikörper gegen C. pneumoniae. Die höchsten Titer werden in der Altersklasse der 5- bis 14-Jährigen gefunden – ein Indiz für das Hauptmanifestationsalter der Primärinfektion. Seroprävalenzdaten aus Deutschland decken sich mit den Angaben aus der internationalen Literatur (5 % der unter 10-Jährigen, 64 % der unter 18-Jährigen besitzen Antikörper gegen C. pneumoniae). Ambulant erworbene Pneumonien werden im Kindesalter möglicherweise in bis zu 18 % der Fälle (serologische Diagnose) durch C. pneumoniae verursacht. Untersuchungen mittels PCR hingegen weisen C. pneumoniae nur in sporadischen Fällen nach. Koinfektionen mit Mykoplasmen, aber auch Pneumokokken und Adenoviren sind keine Seltenheit.

The spread of drug-resistant tuberculosis in children: an Italian case series

Drug-resistant paediatric tuberculosis (TB) is an overlooked global problem. In Italy, the epidemiology of TB has recently changed and data regarding drug-resistant forms in the paediatric setting is scanty. The aim of this case series was to report the cases of drug-resistant TB, diagnosed between June 2006 and July 2010 in four Italian tertiary centres for paediatric infectious diseases, in children and adolescents living in Italy. Twenty-two children were enrolled, of these 17 were resistant to one or more drugs and five had multidrug-resistant TB. All but one child were either foreign born or had at least one foreign parent. Twenty-one patients completed their treatment without clinical or radiological signs of activity at the end of treatment, and one patient was lost to follow up. The outcomes were good, with few adverse effects using second-line anti-TB drugs. Although this series is limited, it might already reflect the worrisome increase of drug-resistant TB, even in childhood.

Controversies in preventive therapy for children contacts of multidrug-resistant tuberculosis

BACKGROUND

Drug-resistant tuberculosis (DR-TB) is emerging as an increasing problem worldwide and no consensus has been reached about the management of children contacts of DR-TB cases.

OBJECTIVE

To evaluate the role of post-exposure chemoprophylaxis in paediatric DR-TB contacts, focusing on literature findings and recommendations from existing international guidelines.

METHODS

We conducted a literature search of the Cochrane Library, MEDLINE by PubMed and EMBASE from database inception through September 2012, using an appropriate search strategy.

RESULTS

Eighteen articles were included: four retrospective and two prospective population studies, eight international guidelines and four narrative reviews.

CONCLUSIONS

General agreement exists that preventive therapy could be beneficial in specific high-risk groups, including immunocompromised children and those aged < 5 years. However, no consensus exists on the use of preventive therapy in older or immunocompetent children and on which regimen should be preferred.

Filgrastim therapy in a child with neutropenia induced by linezolid

We describe the case of a young child with multidrug-resistant tuberculosis, treated with linezolid. The child developed severe neutropenia after 5 months of treatment. Filgrastim was used, a drug that officially is not indicated for non-cytostatic drug-induced neutropenia. This allowed the fast recovery of the patient’s neutrophil-count. However, more experience with the off-label use of filgrastrim is needed in the pediatric population.

Peritoneal tuberculosis due to multidrug-resistant Mycobacterium tuberculosis

The emergence of drug-resistant Mycobacterium tuberculosis has been widely reported throughout the world, but there are very few data regarding children. We describe the case of a 14-year-old Peruvian adolescent who had been living in Italy since the age of 8 years and was diagnosed as having peritoneal tuberculosis (TB). While she was receiving first-line anti-TB therapy, she developed pyrazinamide-associated thrombocytopenia and cultures revealed a multidrug-resistant strain of Mycobacterium tuberculosis. Pyrazinamide, rifampicin and isoniazid were replaced by moxifloxacin, which was continued for 9 months together with ethambutol. The patient recovered without experiencing any drug-related adverse event or the recurrence of TB in the following year. In conclusion, this case illustrates some of the problems that can arise when multidrug-resistant TB has to be treated in children and adolescents, and also highlights the fact that further studies are needed to clarify which drugs should be used and for how long.

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.

Treatment of tuberculosis with levofloxacin or moxifloxacin: report of 6 pediatric cases

We report 6 pediatric cases of tuberculosis caused by Mycobacterium tuberculosis and treated them with levofloxacin or moxifloxacin in the mother-child unit of a university hospital in France between 2005 and 2011. We assess the clinical efficacy and safety of fluoroquinolones and the benefit-risk ratio for their use as second-line antituberculosis drugs in children and adolescents.

Description of pediatric tuberculosis evaluated in a referral center in istanbul Turkey

PURPOSE

Diagnosis of tuberculosis (TB) in children is more challenging than in adults. This study aimed to describe demographical, clinical and laboratory findings of children diagnosed with tuberculosis in Turkey, including the issues of contact tracing, culture positivity and forms of the disease.

MATERIALS AND METHODS

Clinical and laboratory data of 51 children with a mean age of 8.0±4.6 years who were diagnosed with TB were retrospectively reviewed. Main diagnostic tools included tuberculin skin test, chest X-ray, sputum/gastric aspirate culture with sensitivity testing, and direct microscopy for acid-fast bacilli on available samples. Clinical characteristics and outcomes of the patients were examined.

RESULTS

Thirty-six (70.6%) children were diagnosed with intra-thoracic and 15 (29.4%) with extra-thoracic tuberculosis. Twenty-eight of the patients had a positive Bacillus Calmette-Guérin vaccine scar (28/51, 54.9%) and 23/51 (45.1%) had a positive tuberculin skin test. An adult TB contact was identified in 27 (52.9%) of the cases. On direct microscopy, acid-fast bacilli were found in nine (17.6%) patients and positive culture for Mycobacterium tuberculosis was found in 19 (37.3%). Drug resistance to isoniazid was detected in four (7.8%). One patient with nephrotic syndrome and miliary tuberculosis died during follow-up. All other patients responded well to the treatment.

CONCLUSION

Focusing on active contact tracing among all household contacts of tuberculous cases may be helpful in early identification and controlling childhood disease, even in regions with low disease prevalence. Adopting a suspicious and proactive approach in this particular age group is warranted.

Impact of drug resistance on clinical outcome in children with tuberculous meningitis

BACKGROUND

Tuberculous meningitis (TBM) is associated with delayed diagnosis and poor outcome in children. This study investigated the impact of drug resistance on clinical outcome in children with TBM.

METHODS

All children (0-13 years) were included if admitted to Tygerberg Children's Hospital, Cape Town, South Africa, from January 2003 to April 2009 with a diagnosis of either confirmed TBM, or probable TBM with mycobacterial isolation from a site other than cerebrospinal fluid. Mycobacterial samples underwent drug susceptibility testing to rifampin and isoniazid. Children were treated with isoniazid, rifampin, pyrazinamide and ethionamide according to local guidelines.

RESULTS

One hundred twenty-three children were included; 13% (16 of 123) had any form of drug resistance, and 4% (5 of 123) had multidrug-resistant tuberculosis. Time from start of symptoms to appropriate treatment was longer in children with any drug resistance (median: 31 days versus 9 days; P=0.001). In multivariable analysis, young age (P=0.013) and multidrug-resistant tuberculosis (adjusted odds ratio: 12.4 [95% confidence interval: 1.17-132.3]; P=0.037) remained risk factors for unfavorable outcome, and multidrug-resistant tuberculosis remained a risk for death (adjusted odds ratio: 63.9 [95% confidence interval: 4.84-843.2]; P=0.002). We did not detect any difference in outcome between those with isolates resistant to only isoniazid and those with fully susceptible strains (adjusted odds ratio: 0.22 [confidence interval: 0.03-1.87]; P=0.17).

CONCLUSION

Multidrug-resistant TBM in children has poor clinical outcome and is associated with death. We did not find any difference in the outcomes between children with isoniazid monoresistant TBM and those with drug-susceptible TBM. One explanation could be the local treatment regimen. Further investigation of this regimen is indicated.

Pediatric tuberculosis: new guidelines and recommendations

PURPOSE OF REVIEW

To discuss the recommendations pertaining to infants, children, and adolescents in new and updated tuberculosis (TB) guidelines that have been published since 2010 - with emphasis on those from supranational organizations.

RECENT FINDINGS

The main developments in the guidelines covered in this article are related to: novel diagnostics for TB infection, disease, and drug resistance; updated treatment regimens for childhood and drug-resistant TB (DR-TB); and primary and secondary prevention of TB disease in HIV-infected children and adolescents.

SUMMARY

These new guidelines have significant implications for improving pediatric TB care. Regarding diagnosis, current interferon-gamma release assays should not replace tuberculin skin testing, but may be complementary; a polymerase chain reaction assay has been validated for detecting Mycobacterium tuberculosis and rifampicin resistance in microscopy-negative samples, especially in HIV-infected and DR-TB suspects; and a molecular line probe assay has been validated for detecting DR-TB in microscopy-positive samples and culture isolates in DR-TB suspects. With respect to treatment, there have been certain changes in the recent World Health Organization recommendations for certain clinical syndromes, for multidrug-resistant TB disease, and for HIV/TB disease. Concerning prevention, there are new screening algorithms for case finding, and new recommendations for treating HIV-infected children with presumed TB infection and with TB disease with treatment completed (i.e., secondary prophylaxis).

Outcomes of comprehensive care for children empirically treated for multidrug-resistant tuberculosis in a setting of high HIV prevalence

BACKGROUND

Few studies have examined outcomes for children treated for multidrug-resistant tuberculosis (MDR-TB), including those receiving concomitant treatment for MDR-TB and HIV co-infection. In Lesotho, where the adult HIV seroprevalence is estimated to be 24%, we sought to measure outcomes and adverse events in a cohort of children treated for MDR-TB using a community-based treatment delivery model.

METHODS

We reviewed retrospectively the clinical charts of children ≤15 years of age treated for culture-confirmed or suspected MDR-TB between July 2007 and January 2011.

RESULTS

Nineteen children, ages two to 15, received treatment. At baseline, 74% of patients were co-infected with HIV, 63% were malnourished, 84% had severe radiographic findings, and 21% had extrapulmonary disease. Five (26%) children had culture-confirmed MDR-TB, ten (53%) did not have culture results available, and four (21%) subsequently had results indicating drug-susceptible TB. All children with HIV co-infection who were not already on antiretroviral therapy (ART) were initiated on ART a median of two weeks after the start of the MDR-TB regimen. Among the 17 patients with final outcomes, 15 (88%) patients were cured or completed treatment, two (12%) patients died, and none defaulted or were lost to follow-up. The majority of patients (95%) experienced adverse events; only two required permanent discontinuation of the offending agent, and only one required suspension of MDR-TB treatment for more than one week.

CONCLUSIONS

Pediatric MDR-TB and MDR-TB/HIV co-infection can be successfully treated using a combination of social support, close monitoring by community health workers and clinicians, and inpatient care when needed. In this cohort, adverse events were well tolerated and treatment outcomes were comparable to those reported in children with drug-susceptible TB and no HIV infection.

Diagnosis and management of TB in children: an update

In recent years, several notable modifications have occurred in the management of TB infection and disease in children. First, we review new data related to infection, including alternative regimens for the treatment of latent TB, management of drug-resistant infection and preventive therapy in the context of HIV infection. Next, we summarize updated WHO guidelines for the treatment of TB in children, explore issues specific to the management of disease in HIV-infected children, and retreatment of TB, and review pediatric recommendations for the management of drug-resistant TB. Finally, we conclude with a discussion of adjunctive therapy and new drugs in development.

Drug-resistant tuberculosis--current dilemmas, unanswered questions, challenges, and priority needs

Tuberculosis was declared a global emergency by the World Health Organization (WHO) in 1993. Following the declaration and the promotion in 1995 of directly observed treatment short course (DOTS), a cost-effective strategy to contain the tuberculosis epidemic, nearly 7 million lives have been saved compared with the pre-DOTS era, high cure rates have been achieved in most countries worldwide, and the global incidence of tuberculosis has been in a slow decline since the early 2000s. However, the emergence and spread of multidrug-resistant (MDR) tuberculosis, extensively drug-resistant (XDR) tuberculosis, and more recently, totally drug-resistant tuberculosis pose a threat to global tuberculosis control. Multidrug-resistant tuberculosis is a man-made problem. Laboratory facilities for drug susceptibility testing are inadequate in most tuberculosis-endemic countries, especially in Africa; thus diagnosis is missed, routine surveillance is not implemented, and the actual numbers of global drug-resistant tuberculosis cases have yet to be estimated. This exposes an ominous situation and reveals an urgent need for commitment by national programs to health system improvement because the response to MDR tuberculosis requires strong health services in general. Multidrug-resistant tuberculosis and XDR tuberculosis greatly complicate patient management within resource-poor national tuberculosis programs, reducing treatment efficacy and increasing the cost of treatment to the extent that it could bankrupt healthcare financing in tuberculosis-endemic areas. Why, despite nearly 20 years of WHO-promoted activity and >12 years of MDR tuberculosis-specific activity, has the country response to the drug-resistant tuberculosis epidemic been so ineffectual? The current dilemmas, unanswered questions, operational issues, challenges, and priority needs for global drug resistance screening and surveillance, improved treatment regimens, and management of outcomes and prevention of DR tuberculosis are discussed.

Pediatric drug-resistant tuberculosis: a global perspective: a global perspective

This article was based on a presentation given at the 26th International Pediatric Association Conference of Pediatrics, Johannesburg, South Africa, 4-9 August 2010. In 2009, there were 9.4 million new cases of tuberculosis (TB) globally, and, of these, approximately 1 million were pediatric cases. Drug-resistant TB makes up a relatively small proportion of new TB cases, but is much more likely in previously treated cases. Pediatric TB remains difficult to diagnose microbiologically, with the result that detection of drug-resistant TB in children is an ongoing challenge. Since children diagnosed with TB predominantly represent recently acquired TB infection, they provide an important indication of drug-resistant TB prevalence and transmission within their communities. Drug-resistant TB is essentially a man-made problem, which consumes large amounts of healthcare resources. Recent technologic advances may pave the way to more rapid and accurate diagnosis of TB in children. Similarly, these advances are likely to result in improved detection of drug-resistant pediatric TB isolates. The treatment of pediatric drug-resistant TB requires prolonged courses of expensive and potentially toxic drugs, many of which are not available in child-friendly formulations. New anti-TB drugs are at various stages of pre-clinical development and will hopefully allow for shorter, more effective treatment regimens in the not too distant future. HIV-infected children are at extremely high risk for TB acquisition and subsequent progression to symptomatic disease; therefore, many cases of pediatric drug-resistant TB occur in HIV-infected children. This often results in complicated pharmacologic regimens (including anti-TB and antiretroviral drugs) that are difficult to comply with and may have unpredictable interactions. There are limited reports of long-term clinical outcomes of children diagnosed with drug-resistant TB, but improvements in the diagnosis and pharmacologic management of these cases have the potential to improve the quality of care offered to these children.

Paediatric use of second-line anti-tuberculosis agents: a review

Childhood multidrug-resistant tuberculosis (MDR-TB) is an emerging global epidemic. With the imminent roll-out of rapid molecular diagnostic tests, more children are likely to be identified and require treatment. As MDR-TB is resistant to the most effective first-line drugs, clinicians will have to rely on second-line medications which are less effective and often associated with more pronounced adverse effects than first-line therapy. Despite the fact that most of these agents were discovered many years ago, robust information is lacking regarding their pharmacokinetic and pharmacodynamic properties, adverse effects and drug interactions, especially in children. Children differ from adults in the way that drugs are administered, the manner in which they are metabolised and in the adverse effects experienced. The interaction of these drugs with human immunodeficiency virus infection and antiretroviral therapy is also poorly documented. This article reviews the available second-line drugs currently used in the treatment of MDR-TB in children and discusses medication properties and adverse effects while potential interactions with antiretroviral therapy are explored.

Culture-confirmed multidrug-resistant tuberculosis in children: clinical features, treatment, and outcome

BACKGROUND

Multidrug-resistant (MDR) tuberculosis in children is frequently associated with delayed diagnosis and treatment. There is limited evidence regarding the management and outcome of children with MDR-tuberculosis.

METHODS

All children <15 years of age with a diagnosis of culture-confirmed MDR-tuberculosis were included in this retrospective cohort study from 1 January 2003 to 31 December 2008, with follow-up documented until 31 May 2011. We identified children from Brooklyn Hospital for Chest Diseases and Tygerberg Children's Hospital, Western Cape Province, South Africa. Treatment outcomes were defined as 2-month sputum-culture conversion, treatment episode outcome, and survival.

RESULTS

A total of 111 children (median age, 50 months) were included. The diagnosis was delayed in children who had no identified MDR-tuberculosis index case (median delay, 123 vs 58 days; P < .001). Sixty-two percent of patients (53 of 85) were sputum-smear positive, and 43% of patients (43 of 100) were human immunodeficiency virus (HIV) infected. Overall, 82% had favorable treatment outcomes; total mortality was 12%. Malnutrition was associated with failure to culture-convert at 2 months (odds ratio [OR], 4.49 [95% confidence interval {CI}, 1.32-15.2]; P = .02) and death (OR, 15.0 [95% CI, 1.17-192.5]; P = .04) in multivariate analysis. HIV coinfection (OR, 24.7 [95% CI, 1.79-341.1]; P = .02) and the presence of extrapulmonary tuberculosis (OR, 37.8 [95% CI, 2.78-513.4]; P = .006) predicted death.

CONCLUSIONS

Despite advanced disease at presentation and a high prevalence of human immunodeficiency virus coinfection, children with MDR-tuberculosis can be treated successfully, using individualized treatment under routine conditions.