Multidrug-resistant tuberculosis in children: A practical update on epidemiology, diagnosis, treatment and prevention.

Pediatric multidrug-resistant tuberculosis (MDR-TB) remains a significant global problem, and there are numerous barriers preventing children with MDR-TB from being identified, confirmed with microbiologic tests, and treated with a safe, practical, and effective regimen. However, several recent advances in diagnostics and treatment regimens have the promise to improve outcomes for children with MDR-TB. We introduce this review with two cases that exemplify both the challenges in management of MDR-TB in children, but also the potential to achieve a positive outcome. More than 30,000 cases of MDR-TB per year are believed to occur in children but less than 5% are confirmed microbiologically, contributing to poorer outcomes and excess mortality. Rapid molecular-based testing that provides information on rifampin susceptibility is increasingly globally available and recommended for all children suspected of TB disease--but remains limited by challenges obtaining appropriate samples and the paucibacillary nature of most pediatric TB. More complex assays allowing better characterization of drug-resistant isolates are emerging. For children diagnosed with MDR-TB, treatment regimens have traditionally been long and utilize multiple drugs associated with significant side effects, particularly injectable agents. Several new or repurposed drugs including bedaquiline, delamanid, clofazimine and linezolid now allow most treatment regimens to be shorter and all-oral. Yet data to support short, all-oral, novel regimens for young children containing pretomanid remain insufficient at present, and there is a compelling need to conduct pediatric trials of promising therapeutics and MDR-TB treatment regimens.

Corrigendum: Increase in pediatric recurrent fever evaluations during the first year of the COVID-19 pandemic in North America.

[This corrects the article DOI: 10.3389/fped.2023.1240242.].

Increase in pediatric recurrent fever evaluations during the first year of the COVID-19 pandemic in North America.

The impact of the COVID-19 pandemic on new diagnoses of recurrent fevers and autoinflammatory diseases is largely unknown. The Childhood Arthritis and Rheumatology Research Alliance (CARRA) PFAPA/AID Working Group aimed to investigate the impact of the COVID-19 pandemic on the number of pediatric patients evaluated for recurrent fevers and autoinflammatory diseases in North America. The absolute number of new outpatient visits and the proportion of these visits attributed to recurrent fever diagnoses during the pre-pandemic period (1 March 2019-29 February 2020) and the first year of the COVID-19 pandemic (1 March 2020-28 February 2021) were examined. Data were collected from 27 sites in the United States and Canada. Our results showed an increase in the absolute number of new visits for recurrent fever evaluations in 21 of 27 sites during the COVID-19 pandemic compared to the pre-pandemic period. The increase was observed across different geographic regions in North America. Additionally, the proportion of new visits to these centers for recurrent fever in relation to all new patient evaluations was significantly higher during the first year of the pandemic, increasing from 7.8% before the pandemic to 10.9% during the pandemic year (p < 0.001). Our findings showed that the first year of the COVID-19 pandemic was associated with a higher number of evaluations by pediatric subspecialists for recurrent fevers. Further research is needed to understand the reasons behind these findings and to explore non-infectious triggers for recurrent fevers in children.

Exposure-safety relationship for acyclovir in the treatment of neonatal herpes simplex virus disease.

BACKGROUND: Neonatal herpes simplex virus (HSV) disease has been treated with high-dose (20 mg/kg/dose) acyclovir since 1991. AIMS: Determine the safety of acyclovir in infants with neonatal HSV treated with high-dose acyclovir; examine the association between acyclovir dose and exposure with adverse events (AEs). STUDY DESIGN: We obtained demographic information and acyclovir dosing via medical records. Acyclovir exposure was calculated using an established pharmacokinetic model. SUBJECTS: Infants <120 days of age with neonatal HSV discharged from four academic children's hospitals. OUTCOME MEASURES: We identified clinical and laboratory adverse events (AEs). RESULTS AND CONCLUSIONS: We identified 49 infants with neonatal HSV treated with acyclovir; 42 infants had complete 21-day dosing information. Median mean daily dose was 59 mg/kg/day. Clinical AEs were common among all gestational and postnatal age groups. Rash was the most common clinical AE (37 %). Mild laboratory AEs occurred in 2-37 % of infants. The median maximum doses (mg/kg/day) were higher among infants with hypokalemia, elevated blood urea nitrogen, and thrombocytosis. For all other laboratory AEs, the median maximum doses for infants without events were higher or equal to the median maximum dose of infants with the AE. The odds of experiencing any clinical or laboratory AE did not differ by predicted acyclovir exposure for either area under the curve (AUC) or maximum concentration (Cmax) (odds ratio [OR] = 1.00 [0.98, 1.03] and OR = 1.01 [0.93, 1.12], respectively). Although AEs were common with high-dose acyclovir exposure, severe AEs were rare. Acyclovir exposure was not associated with AEs.

Implementation of Vancomycin Therapeutic Monitoring Guidelines: Focus on Bayesian Estimation Tools in Neonatal and Pediatric Patients.

BACKGROUND: The 2020 consensus guidelines for vancomycin therapeutic monitoring recommend using Bayesian estimation targeting the ratio of the area under the curve over 24 hours to minimum inhibitory concentration as an optimal approach to individualize therapy in pediatric patients. To support institutional guideline implementation in children, the objective of this study was to comprehensively assess and compare published population-based pharmacokinetic (PK) vancomycin models and available Bayesian estimation tools, specific to neonatal and pediatric patients. METHODS: PubMed and Embase databases were searched from January 1994 to December 2020 for studies in which a vancomycin population PK model was developed to determine clearance and volume of distribution in neonatal and pediatric populations. Available Bayesian software programs were identified and assessed from published articles, software program websites, and direct communication with the software company. In the present review, 14 neonatal and 20 pediatric models were included. Six programs (Adult and Pediatric Kinetics, BestDose, DoseMeRx, InsightRx, MwPharm++, and PrecisePK) were evaluated. RESULTS: Among neonatal models, Frymoyer et al and Capparelli et al used the largest PK samples to generate their models, which were externally validated. Among the pediatric models, Le et al used the largest sample size, with multiple external validations. Of the Bayesian programs, DoseMeRx, InsightRx, and PrecisePK used clinically validated neonatal and pediatric models. CONCLUSIONS: To optimize vancomycin use in neonatal and pediatric patients, clinicians should focus on selecting a model that best fits their patient population and use Bayesian estimation tools for therapeutic area under the -curve-targeted dosing and monitoring.

Invasive Mycobacterium abscessus Outbreak at a Pediatric Dental Clinic.

BACKGROUND: Mycobacterium species, specifically M. abscessus and M. chelonae (MABs), are known to contaminate water systems and are uncommon causes of health care-associated infection, but morbidity can be significant and treatment complex. METHODS: Odontogenic MAB infections occurred in patients following pulpotomy procedures at dental clinic A from 1 January to 6 September 2016. We identified confirmed and probable cases using culture data, imaging, pathology results, and surgical findings. Epidemiologic and clinical data including demographics, symptoms, laboratory findings, treatment regimens, and outcomes were extracted. RESULTS: Of 1082 at-risk patients, 71 case patients (22 confirmed; 49 probable) were identified. Median age was 6 years. Median symptom onset was 85 days postpulpotomy. Pain and/or swelling on admission occurred in 79%. On imaging, 49 of 70 had abnormalities of the mandible or maxilla, 13 of 70 had lymphadenopathy, and 19 of 68 had pulmonary nodules. Seventy were hospitalized (average of 8.5 days). Intravenous antibiotics were administered to 32 cases for a median length of 137 days. Clofazimine was administered to 29 patients as part of their multidrug regimen. Antibiotic treatment was associated with many adverse effects. Treated children showed evidence of jaw healing with resolved/improving pulmonary nodules at 1-year follow-up. CONCLUSIONS: This is the largest outbreak of invasive MAB infections associated with a pediatric dental practice. While infections were indolent, patients suffered medical and surgical consequences of treatment, including permanent tooth loss. Identification of this outbreak led to a change in water standards for pediatric dental procedures in California. Enhanced national dental water quality standards are needed to prevent future outbreaks.

A Pediatric Infectious Diseases Perspective of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) and Novel Coronavirus Disease 2019 (COVID-19) in Children.

Understanding the role that children play in the clinical burden and propagation of severe acute respiratory syndrome coronavirus 2, responsible for coronavirus disease 2019 (COVID-19) infections, is emerging. While the severe manifestations and acute clinical burden of COVID-19 have largely spared children compared with adults, understanding the epidemiology, clinical presentation, diagnostics, management, and prevention opportunities and the social and behavioral impacts on child health is vital. Foremost is clarifying the contribution of asymptomatic and mild infections to transmission within the household and community and the clinical and epidemiologic significance of uncommon severe post-infectious complications. Here, we summarize the current knowledge, identify resources, and outline research opportunities. Pediatric infectious diseases clinicians have a unique opportunity to advocate for the inclusion of children in epidemiological, clinical, treatment, and prevention studies to optimize their care as well as to represent children in the development of guidance and policy during pandemic response.

Safety and Tolerability of Clofazimine in a Cohort of Children With Odontogenic Mycobacterium abscessus Infection.

Mycobacterium abscessus infections can be challenging to treat. Clofazimine has excellent in vitro activity against M abscessus, but reports of its use, particularly in children, have been limited. In this study, clofazimine was given to 27 children during an outbreak of odontogenic mycobacterial infections and seemed to be well tolerated as part of a multidrug regimen.

Population Pharmacokinetics and Safety of Solithromycin following Intravenous and Oral Administration in Infants, Children, and Adolescents.

Solithromycin is a novel fluoroketolide antibiotic which was under investigation for the treatment of community-acquired bacterial pneumonia (CABP). A phase 1 study was performed to characterize the pharmacokinetics (PK) and safety of solithromycin in children. Eighty-four subjects (median age, 6 years [age range, 4 days to 17 years]) were administered intravenous (i.v.) or oral (capsules or suspension) solithromycin (i.v., 6 to 8 mg/kg of body weight; capsules/suspension, 14 to 16 mg/kg on days 1 and 7 to 15 mg/kg on days 2 to 5). PK samples were collected after the first and multidose administration. Data from 83 subjects (662 samples) were combined with previously collected adolescent PK data (n = 13; median age, 16 years [age range, 12 to 17 years]) following capsule administration to perform a population PK analysis. A 2-compartment PK model characterized the data well, and postmenstrual age was the only significant covariate after accounting for body size differences. Dosing simulations suggested that 8 mg/kg i.v. daily and oral dosing of 20 mg/kg on day 1 (800-mg adult maximum) followed by 10 mg/kg on days 2 to 5 (400-mg adult maximum) would achieve a pediatric solithromycin exposure consistent with the exposures observed in adults. Seventy-six treatment-emergent adverse events (TEAEs) were reported in 40 subjects. Diarrhea (6 subjects) and infusion site pain or phlebitis (3 subjects) were the most frequently reported adverse events related to treatment. Two subjects experienced TEAEs of increased hepatic enzymes that were deemed not to be related to the study treatment. (The phase 1 pediatric studies discussed in this paper have been registered at ClinicalTrials.gov under identifiers NCT01966055 and NCT02268279.).

Population-Based Pharmacokinetic Modeling of Vancomycin in Children with Renal Insufficiency.

BACKGROUND: Vancomycin dosing to achieve the area-under-the-curve to minimum inhibitory concentration (AUC/MIC) target of ≥ 400 in children with renal insufficiency is unknown. Our objectives were to compare vancomycin clearance (CL) and initial dosing in children with normal and impaired renal function. METHODS: Using a matched case-control study in subjects ≥ 3 months old who received vancomycin ≥ 48 hr, we performed population-based modeling with empiric Bayesian post-hoc individual parameter estimations and Monte Carlo simulations. Cases, defined by baseline serum creatinine (SCr) ≥ 0.9 mg/dL, were matched 1:1 to controls by age and weight. RESULTS: Analysis included 63 matched pairs with 319 serum concentrations. Mean age (± SD) was 13 ± 6 yr and weight, 51 ± 25 kg. Mean baseline SCr was 0.6 ± 0.2 mg/dL for controls, and 1.3 ± 0.5 for cases. Age, SCr, and weight were independent covariates for CL. Final model parameters and inter-subject variability (ISV) were: CL(L/hr) = 0.235*Weight0.75*(0.64/SCr)0.497*(ln(DOL)/8.6)1.19 ISV=39%, where DOL is day of life. Target AUC/MIC ≥ 400 was achieved in 80% of cases at vancomycin 45 mg/kg/day, but required 60 mg/kg/day for controls. Drug CL improved in 87% of cases due to recovery of renal function. CONCLUSION: Due to reduced CL, a less frequent dosing at 15 mg/kg every 8 hr (i.e., 45 mg/kg/day) may be appropriate for some children with renal impairment. Close monitoring of renal function and drug concentrations is prudent to ensure adequate drug exposure, especially in those with renal impairment since recovery of renal function may occur during therapy.

Management of latent tuberculosis infection in child contacts of multidrug-resistant tuberculosis.

After exposure to a teacher with multidrug-resistant pulmonary tuberculosis, 31 children developed latent infection. Twenty-six were treated with levofloxacin and pyrazinamide. Twelve required a change in therapy secondary to adverse effects. The most common adverse effects included abdominal pain, arthralgias/myalgias and elevated transaminases. All children reported at least 1 adverse effect. Fifteen children completed treatment. All adverse effects were transient.

Time to initiation of antifungal therapy for neonatal candidiasis.

The effect of delayed antifungal therapy in critically ill infants with invasive candidiasis has not been studied. Our objective was to evaluate the effect of time to initiation of antifungal therapy (TIA) on mortality, disseminated disease, and postinfection hospital stay. We conducted a cohort study of critically ill infants with cultures positive for Candida from 1990 to 2008. TIA was defined as the number of hours from the collection of the first positive culture until the start of antifungal therapy. Of 96 infants, 57% were male, the median gestational age was 27 weeks (range, 23 to 41 weeks), and the median birth weight was 956 g (range, 415 to 6,191 g). Most subjects received amphotericin B deoxycholate. TIA was ≤ 24 h for 35% of infants, between 25 and 48 h for 42%, and >48 h for 23%. Eleven subjects died during hospitalization, and 22% had disseminated candidiasis. The median duration of hospital stay postinfection was 53 days (range, 6 to 217 days). Both univariate and multivariate analyses demonstrated that TIA was not associated with mortality, disseminated disease, or hospital stay postinfection. However, ventilator use for >60 days significantly increased the risk of death (odds ratio [OR], 9.5; 95% confidence interval [CI], 2.2 to 66.7; P = 0.002). Prolonged candidemia increased the risk of disseminated disease by 10% per day of positive culture (OR, 1.1; 95% CI, 1.08 to 1.2; P = 0.007), and low gestational age was associated with increased neonatal intensive care unit (NICU) stay after the first positive Candida culture by 0.94 weeks (95% CI, 0.70 to 0.98; P < 0.001). The TIA was not associated with all-cause mortality, disseminated candidiasis, and postinfection length of hospital stay.

Evaluation of indirect fluorescent antibody assays compared to rapid influenza diagnostic tests for the detection of pandemic influenza A (H1N1) pdm09.

Performance of indirect fluorescent antibody (IFA) assays and rapid influenza diagnostic tests (RIDT) during the 2009 H1N1 pandemic was evaluated, along with the relative effects of age and illness severity on test accuracy. Clinicians and laboratories submitted specimens on patients with respiratory illness to public health from April to mid October 2009 for polymerase chain reaction (PCR) testing as part of pandemic H1N1 surveillance efforts in Orange County, CA; IFA and RIDT were performed in clinical settings. Sensitivity and specificity for detection of the 2009 pandemic H1N1 strain, now officially named influenza A(H1N1)pdm09, were calculated for 638 specimens. Overall, approximately 30% of IFA tests and RIDTs tested by PCR were falsely negative (sensitivity 71% and 69%, respectively). Sensitivity of RIDT ranged from 45% to 84% depending on severity and age of patients. In hospitalized children, sensitivity of IFA (75%) was similar to RIDT (84%). Specificity of tests performed on hospitalized children was 94% for IFA and 80% for RIDT. Overall sensitivity of RIDT in this study was comparable to previously published studies on pandemic H1N1 influenza and sensitivity of IFA was similar to what has been reported in children for seasonal influenza. Both diagnostic tests produced a high number of false negatives and should not be used to rule out influenza infection.

Clinical and laboratory features of pertussis in infants at the onset of a California epidemic.

We report clinical characteristics and outcome of infants <3 months of age hospitalized with pertussis compared with viral respiratory infection (respiratory syncytial virus and influenza). Patients with pertussis more often were afebrile, had more visits before admission, and had longer hospital stays. Household coughing contacts were common.

Complications associated with outpatient parenteral antibiotic therapy in children.

BACKGROUND: The authors sought to determine the prevalence, risk factors, and clinical impact of complications associated with outpatient parenteral antimicrobial therapy (OPAT) in children. METHODS: A cohort of patients ≤18 years old with infections, who received OPAT were evaluated retrospectively. Antibiotic-associated complications (AACs), catheter-associated complications (CACs), and unplanned medical care visits were the main outcome measures. RESULTS: Overall, 36 complications (25 CACs and 11 AACs) occurred in 32 of 98 patients. Mean age of patients, race, gender, and infecting organism did not differ between study groups. The use of OPAT for osteomyelitis was associated with complications (odds ratio = 2.69; 95% confidence interval = 0.99-7.35; P = .05). All patients, except for 4 who had complications, clinically improved by the end of OPAT. Unplanned medical visits occurred in 17 patients, 15 of which were because of CACs. CONCLUSION: Complications occurred commonly in children receiving OPAT and resulted in unplanned medical visits.

Nephrotoxicity associated with amphotericin B deoxycholate in neonates.

BACKGROUND: The prevalence of nephrotoxicity in neonates receiving amphotericin B deoxycholate (amphoB) is not well-defined. While some studies report a lack of toxicity, others claim a frequency as high as 85%. METHODS: We reviewed medical records of all infants < or = 90 days of age in the neonatal intensive care unit who received at least 3 doses of amphoB between January 1990 and December 2004. A standardized form was used to collect demographic, therapeutic, microbiologic, and laboratory data for each patient. Nephrotoxicity was defined as a rise in serum creatinine (SCr) of at least 0.4 mg/dL any time during amphoB therapy. RESULTS: A total of 92 infants met entry criteria. Median gestational age was 26 (range: 23-41) weeks and median birth weight was 863 (range: 546-4000) grams. Overall, 15 (16%) infants experienced nephrotoxicity, and 16 (17%) developed hypokalemia (<3.0 mmol/L). There were no differences between infants who did or did not develop nephrotoxicity in terms of gestational age, birth weight, gender, underlying medical conditions, or use of other potentially nephrotoxic medications. AmphoB exposure and duration of therapy were similar between infants who developed nephrotoxicity and those who did not, with a mean cumulative dose of 13.5 +/- 9.6 mg/kg and duration of 16.3 +/- 10.4 days. With the exception of 1 infant, the elevated SCr values resolved in all infants by the end of amphoB therapy. CONCLUSION: AmphoB administration does not appear to be associated with lasting measurable nephrotoxicity in neonates. Because of changes in serum creatinine and potassium, renal function and potassium levels should be monitored closely in infants receiving amphoB.