The use of proton pump inhibitors in children: a comprehensive review

Physiologically-based pharmacokinetic modeling of pantoprazole to evaluate the role of CYP2C19 genetic variation and obesity in the pediatric population

Pantoprazole is a proton pump inhibitor indicated for the treatment of gastroesophageal reflux disease, a condition that disproportionately affects children with obesity. Appropriately dosing pantoprazole in children with obesity requires understanding the body size metric that best guides dosing, but pharmacokinetic (PK) trials using traditional techniques are limited by the need for larger sample sizes and frequent blood sampling. Physiologically-based PK (PBPK) models are an attractive alternative that can account for physiologic-, genetic-, and drug-specific changes without the need for extensive clinical trial data. In this study, we explored the effect of obesity on pantoprazole PK and evaluated label-suggested dosing in this population. An adult PBPK model for pantoprazole was developed using data from the literature and accounting for genetic variation in CYP2C19. The adult PBPK model was scaled to children without obesity using age-associated changes in anatomical and physiological parameters. Lastly, the pediatric PBPK model was expanded to children with obesity. Three pantoprazole dosing strategies were evaluated: 1 mg/kg total body weight, 1.2 mg/kg lean body weight, and US Food and Drug Administration-recommended weight-tiered dosing. Simulated concentration-time profiles from our model were compared with data from a prospective cohort study (PAN01; NCT02186652). Weight-tiered dosing resulted in the most (>90%) children with pantoprazole exposures in the reference range, regardless of obesity status or CYP2C19 phenotype, confirming results from previously published population PK models. PBPK models may allow for the efficient study of physiologic and developmental effects of obesity on PK in special populations where clinical trial data may be limited.

A Case of Severe Proton Pump Inhibitor-Induced Hypomagnesemia Refractory to Continuous Oral and Intravenous Magnesium Replenishment

Proton pump inhibitors (PPIs) are frequently used medications to treat a wide variety of gastrointestinal conditions. By irreversibly inhibiting the hydrogen-potassium ATPase pump, they remarkably reduce gastric acid secretion. However, chronic PPI intake can result in serious complications, including severe hypomagnesemia. The following case report presents a severe case of refractory PPI-induced hypomagnesemia (PPIH), resistant to continuous oral and intravenous magnesium replacement, in a 70-year-old male patient, with a long history of PPI use due to persistent epigastric pain. Upon each of the 10 admissions to the hospital, he presented with severe signs and symptoms of hypomagnesemia, such as nausea, muscle fasciculation, diffuse cramps, weakness, neuromuscular irritability, and ECG disturbances, including non-specific T-wave abnormalities. In fact, PPIH has been reported for the first time in 2006. It is believed that the excessive, chronic intake of PPIs can disturb the normal functioning of the transient receptor potential melastatin 6/7 (TRPM 6/7), which is the main pathway of active intestinal magnesium absorption, leading to hypomagnesemia. PPIH is typically characterized by stubborn resistance to oral and intravenous magnesium replenishment but usually resolves after PPI withdrawal. Hence, despite being among the safest and most commonly prescribed drugs, PPI intake should be closely monitored when prolonged usage is planned. Additionally, continuous follow-up and regular assessment of serum magnesium levels are crucial to avoid the occurrence of PPIH and to prevent its potentially deleterious complications, including life-threatening arrhythmias.

Characteristics of esophageal refluxate and symptoms in infants compared between pre-treatment and on treatment with proton pump inhibitors

OBJECTIVE

To examine longitudinal pH-impedance characteristics from those infants who remained on proton pump inhibitors therapy for gastroesophageal reflux disease (GERD) as parents/providers refused to discontinue therapy after 4 weeks.

STUDY DESIGN

Eighteen infants with acid reflux index >3% underwent treatment, and pH-impedance data were compared prior to and on proton pump inhibitors at 42 ± 1 and 46 ± 1 weeks' postmenstrual age, respectively. Esophageal acid and bolus exposure, symptoms and swallowing characteristics were examined.

RESULTS

Proton pump inhibitors reduces the acid-mediated effects of reflux but modifies impedance and clearance mechanisms (P < 0.05). Prolonged therapy did not reduce symptoms (P > 0.05). Infants evaluated while on proton pump inhibitors were 1.8 times more likely to have swallows before and after reflux.

CONCLUSIONS

Prescription of proton pump inhibitors for objectively determined GERD should have time limits, as prolonged treatment can result in prolonged esophageal bolus clearance time without relieving symptoms.

Children and Adolescents with Irritable Bowel Syndrome: Treatment and Management

BACKGROUND

Irritable bowel syndrome (IBS) is a disorder that causes stomach pain in children and adolescents. It may also impact one's quality of life. IBS is linked to gastrointestinal issues such as diarrhoea and constipation. Despite the identification of several potential pathophysiological pathways, the aetiology of IBS remained unknown.

OBJECTIVE

The aim of this paper is to discuss the diagnosis, pathogenesis, case studies and treatment of Irritable bowel syndrome in children and adolescents.

METHODS

This systematic review covered relevant papers from the previous ten years that were accessible in Science Direct, Elsevier, NCBI, and Web of Science related to the pathophysiology and function of pharmacological drugs such as antidepressants, antispasmodics, prokinetics, and antibiotics in children with irritable bowel syndrome.

RESULTS

Only a few prospective therapy techniques have been investigated in children, and even fewer of those have been demonstrated to be effective. This article presents case studies including 50-59 children, which demonstrate a favourable acceptable impact that is more effective than a placebo in terms of reducing symptoms and improving the overall quality of life in children who have irritable bowel syndrome. Furthermore, the majority of the pathophysiological explanations and treatment options discussed are based on adult studies. These major issues arose when treating paediatric IBS, and they must be addressed in order to properly treat children with IBS. Trials that focus on many combinations of pharmacological and non-pharmacological therapies seem to be more helpful.

DISCUSSION

In recent years, a number of systematic reviews have been conducted to evaluate the efficacy of medication treatments in children for IBS; however, the dependability of these systematic reviews needs to be further investigated owing to the various experimental designs and levels of evidence used. This article highlights paediatric therapy options, including pharmaceutical medications such as antidepressants, antispasmodics, prokinetics, and antibiotics. The goal is to alleviate IBS symptoms while also enhancing the quality of life for children with this illness.

Inhibition of gastric acid secretion with omeprazole affects fish specific dynamic action and growth rate: Implications for the development of phenotypic stomach loss

An acid-secreting stomach provides many selective advantages to fish and other vertebrates; however, phenotypic stomach loss has occurred independently multiple times and is linked to loss of expression of both the gastric proton pump and the protease pepsin. Reasons underpinning stomach loss remain uncertain. Understanding the importance of gastric acid-secretion to the metabolic costs of digestion and growth will provide information about the metabolic expense of acid-production and performance. In this study, omeprazole, a well characterized gastric proton pump inhibitor, was used to simulate the agastric phenotype by significantly inhibiting gastric acidification in Nile tilapia. The effects on post-prandial metabolic rate and growth were assessed using intermittent flow respirometry and growth trials, respectively. Omeprazole reduced the duration (34.4%) and magnitude (34.5%) of the specific dynamic action and specific growth rate (21.3%) suggesting a decrease in digestion and assimilation of the meal. Gastric pH was measured in control and omeprazole treated fish to confirm that gastric acid secretion was inhibited for up to 12 h post-treatment (p &lt; 0.05). Gastric evacuation measurements confirm a more rapid emptying of the stomach in omeprazole treated fish. These findings reinforce the importance of stomach acidification in digestion and growth and present a novel way of determining costs of gastric digestion.

Perspectives from the Society for Pediatric Research: pharmacogenetics for pediatricians

This review evaluates the pediatric evidence for pharmacogenetic associations for drugs that are commonly prescribed by or encountered by pediatric clinicians across multiple subspecialties, organized from most to least pediatric evidence. We begin with the pharmacogenetic research that led to the warning of increased risk of death in certain pediatric populations ("ultrarapid metabolizers") who are prescribed codeine after tonsillectomy or adenoidectomy. We review the evidence for genetic testing for thiopurine metabolism, which has become routine in multiple pediatric subspecialties. We discuss the pharmacogenetic research in proton pump inhibitors, for which clinical guidelines have recently been made available. With an increase in the prevalence of behavioral health disorders including attention deficit hyperactivity disorder (ADHD), we review the pharmacogenetic literature on selective serotonin reuptake inhibitors, selective norepinephrine reuptake inhibitors, and ADHD medications. We will conclude this section on the current pharmacogenetic data on ondansetron. We also provide our perspective on how to integrate the current research on pharmacogenetics into clinical care and what further research is needed. We discuss how institutions are managing pharmacogenetic test results and implementing them clinically, and how the electronic health record can be leveraged to ensure testing results are available and taken into consideration when prescribing medications. IMPACT: While many reviews of pharmacogenetics literature are available, there are few focused on pediatrics. Pediatricians across subspecialties will become more comfortable with pharmacogenetics terminology, know resources they can use to help inform their prescribing habits for drugs with known pharmacogenetic associations, and understand the limitations of testing and where further research is needed.

Rectal Omeprazole in Infants With Gastroesophageal Reflux Disease: A Randomized Pilot Trial

BACKGROUND AND OBJECTIVE

Omeprazole is a proton pump inhibitor that is used in acid suppression therapy in infants. Infants cannot swallow the oral tablets or capsules. Since, infants require a non-standard dose of omeprazole, the granules or tablets are often crushed or suspended in water or sodium bicarbonate, which may destroy the enteric coating. In this study we explore the efficacy and pharmacokinetics of rectally administered omeprazole in infants with gastroesophageal reflux disease (GERD) due to esophageal atresia (EA) or congenital diaphragmatic hernia (CDH) and compare these with orally administered omeprazole.

METHODS

Infants (6-12 weeks postnatal and bodyweight > 3 kg) with EA or CDH and GERD were randomized to receive a single dose of 1 mg/kg omeprazole rectally or orally. The primary outcome was the percentage of infants for whom omeprazole was effective according to predefined criteria for 24-h intraesophageal pH. Secondary outcomes were the percentages of time that gastric pH was < 3 or < 4, as well as the pharmacokinetic parameters.

RESULTS

Seventeen infants, 4 with EA and 13 with CDH, were included. The proportion of infants for whom omeprazole was effective was 56% (5 of 9 infants) after rectal administration and 50% (4 of 8 infants) after oral administration. The total reflux time in minutes and percentages and the number of reflux episodes of pH < 4 decreased statistically significantly after both rectal and oral omeprazole administration. Rectal and oral administration of omeprazole resulted in similar serum exposure.

CONCLUSIONS

A single rectal omeprazole dose (1 mg/kg) results in consistent increases in intraesophageal and gastric pH in infants with EA- or CDH-related GERD, similar to an oral dose. Considering the challenges with existing oral formulations, rectal omeprazole presents as an innovative, promising alternative for infants with pathological GERD.

CLINICAL TRIAL REGISTER

ClinicalTrials.gov Identifier: NCT00226044.

Development and Stability Study of an Omeprazole Suppository for Infants

Background and Objective

Omeprazole is a proton pump inhibitor (PPI) that is used in acid suppression therapy in infants. In this study we aimed to develop a pediatric omeprazole suppository, with good physical and chemical stability, suitable for pharmaceutical batch production.

Methods

The composition of the suppository consisted of omeprazole, witepsol H15 and arginine (L) base. To achieve evenly distributed omeprazole suspension suppositories, the temperature, stirring rate, and arginine (L) base amount were varied. A previously validated quantitative high-performance liquid chromatography–ultraviolet method was modified and a long-term stability study was performed for one year.

Results

Evenly distributed omeprazole suspension suppositories were obtained by adding 100 mg arginine (L) base and pouring at a temperature of 34.7 °C and a stirring speed of 200 rpm. The long-term stability study showed no signs of discoloration and a stable omeprazole content between 90 and 110% over 1 year if stored in the dark at room temperature.

Conclusion

We developed a pediatric omeprazole suppository. This formulation may provide a good alternative to manipulated commercial or extemporaneously compounded omeprazole oral formulations for infants. Clinical studies are needed to establish efficacy and safety in this young population.

Drugs in Focus: Proton Pump Inhibitors

Proton pump inhibitors (PPIs) are amongst the most commonly prescribed drugs in infants and children with the last decades witnessing a dramatic rise in their utilization. Although PPIs are clearly effective when used appropriately and have been regarded as safe drugs, there is growing evidence regarding their potential adverse effects. Although, largely based on adult data it is clear that many of these are also relevant to pediatrics. PPI use potentially affects gastrointestinal microbiota composition and function, decreases defence against pathogens resulting in increased risk for infections, interferes with absorption of minerals and vitamins leading to specific deficiencies and increased risk for bone fractures as well as interferes with protein digestion resulting in increased risk of sensitization to allergens and development of allergic diseases and eosinophilic esophagitis. An association with gastric, liver and pancreatic cancer has also been inferred from adult data but is tenuous and causation is not proven. Overall, evidence for these adverse events is patchy and not always compelling. Overall, the use of PPIs, for selected indications with a good evidence base, has significant potential benefit but carries more caution in infants and children. Pediatricians should be aware of the concerns regarding the potential adverse events associated with their use.

The updated JSPGHAN guidelines for the management of Helicobacter pylori infection in childhood

The Japan Pediatric Helicobacter pylori Study Group published the first guidelines on childhood H. pylori infection in 1997. They were later revised by the Japanese Society for Pediatric Gastroenterology, Hepatology and Nutrition (JSPGHAN). The H. pylori eradication rates, when employing triple therapy with amoxicillin and clarithromycin, currently recommended as the first-line therapy of H. pylori infection in Japan, have substantially decreased, creating an important clinical problem worldwide. In Japanese adults, the "test-and-treat" strategy for H. pylori infection is under consideration as an approach for gastric cancer prevention. However, the combined North American and European pediatric guidelines have rejected such a strategy for asymptomatic children. As risk for gastric cancer development is high in Japan, determining whether the "test-and-treat" strategy can be recommended in children has become an urgent matter. Accordingly, the JSPGHAN has produced a second revision of the H. pylori guidelines, which includes discussion about the issues mentioned above. They consist of 19 clinical questions and 34 statements. An H. pylori culture from gastric biopsies is recommended, not only as a diagnostic test for active infection but for antimicrobial susceptibility testing to optimize eradication therapy. Based upon antimicrobial susceptibility testing of H. pylori strains (especially involving clarithromycin), an eradication regimen including use of the antibiotics to which H. pylori is susceptible is recommended as the first-line therapy against H. pylori-associated diseases. The guidelines recommend against a "test-and-treat" strategy for H. pylori infection for asymptomatic children to protect against the development of gastric cancer because there has been no evidence supporting this strategy.

Proton pump inhibitor administration in neonates and infants. Lack of consensus - An ASPO survey

OBJECTIVE

Laryngopharyngeal and Gastroesophageal reflux (LPR and GER) are distinct clinical entities that present with a range of non-specific symptoms. The exact prevalence in the pediatric population is unknown. While there has been an increase in the use of PPIs, lack of clear guidelines, conflicting evidence regarding efficacy and safety concerns with long-term use require physicians to use their own anecdotal experience and clinical judgement when treating patients. The goal of this study was to evaluate practice patterns among pediatric otolaryngologists regarding the use of proton-pump inhibitors for reflux-related conditions.

METHODS

A survey was submitted to American Society of Pediatric Otolaryngology (ASPO) members to determine practice patterns regarding use of PPIs for reflux-related conditions in the newborn and infant population. Statistical analysis using Fisher's exact test was performed.

RESULTS

37% of respondents would not prescribe PO PPIs in neonates, with 50% not prescribing IV PPIs. 60% would prescribe a PPI as second or third-line treatment for infants (10 weeks to 1-year). Only 10% would prescribe as first-line in this age group. 48% would prescribe PPIs once daily and 19% as BID. No significant practice differences exist based on years of experience, number of relevant patients seen, and setting of practice.

CONCLUSION

There was no agreement regarding dosage, frequency and duration of PPI treatment for reflux disease in neonates and infants. There was also no correlation with experience or practice setting. This emphasizes the need for a multidisciplinary approach and consensus statement to guide management of GER and LPR in this population.

CYP2C19 Phenotype and Risk of Proton Pump Inhibitor-Associated Infections

OBJECTIVES

Proton pump inhibitors (PPIs) are often used in pediatrics to treat common gastrointestinal disorders, and there are growing concerns for infectious adverse events. Because CYP2C19 inactivates PPIs, genetic variants that increase CYP2C19 function may decrease PPI exposure and infections. We tested the hypothesis that CYP2C19 metabolizer phenotypes are associated with infection event rates in children exposed to PPIs.

METHODS

This retrospective biorepository cohort study included individuals aged 0 to 36 months at the time of PPI exposure. Respiratory tract and gastrointestinal tract infection events were identified by using International Classification of Diseases codes in the year after the first PPI mention. Variants defining CYP2C19 *2, *3, *4, *8, *9, and *17 were genotyped, and all individuals were classified as CYP2C19 poor or intermediate, normal metabolizers (NMs), or rapid or ultrarapid metabolizers (RM/UMs). Infection rates were compared by using univariate and multivariate analyses.

RESULTS

In all, 670 individuals were included (median age 7 months; 44% girls). CYP2C19 NMs (n = 267; 40%) had a higher infection rate than RM/UMs (n = 220; 33%; median 2 vs 1 infections per person per year; P = .03). There was no difference between poor or intermediate (n = 183; 27%) and NMs. In multivariable analysis of NMs and RM/UMs adjusting for age, sex, PPI dose, and comorbidities, CYP2C19 metabolizer status remained a significant risk factor for infection events (odds ratio 0.70 [95% confidence interval 0.50-0.97] for RM/UMs versus NMs).

CONCLUSIONS

PPI therapy is associated with higher infection rates in children with normal CYP2C19 function than in those with increased CYP2C19 function, highlighting this adverse effect of PPI therapy and the relevance of CYP2C19 genotypes to PPI therapeutic decision-making.

Management of Orbital Complications of Acute Rhinosinusitis in Pediatric Patients: A 15-Year Single-Center Experience

BACKGROUND

The major clinical dilemma managing acute rhinosinusitis (ARS) in pediatric population is distinguishing uncomplicated rhinosinusitis from a complicated bacterial ARS and orbital complications, the latter requiring antimicrobials and surgical intervention. However, factors associated with severe orbital complications and the optimum management strategy remains controversial. The objectives of this study were to characterize the clinical outcomes of children with orbital complications of ARS and to identify risk factors associated with disease severity.

METHODS

This retrospective cohort analysis evaluated the clinical outcomes of 61 children admitted for orbital complications between January 1, 2002 and December 31, 2017. Descriptive statistics were performed to examine the demographics and clinical findings. We compared groups using Mann-Whitney U test for continuous variables and χ for categorical variables.

RESULTS

Although two-thirds of children had received prehospital antibiotics, half of the cohort presented with post-septal orbital complications. While 83% of isolates obtained from the same patients were susceptible to the prehospital antibiotics given, the majority of those who received prehospital antibiotics nevertheless required surgical intervention. We observed significant association between the age of presentation and disease severity. Children >5 years of age presented with more severe orbital complications despite prehospital antibiotics and were more likely to require surgical intervention (P < 0.001).

CONCLUSIONS

In this study, stage II/III orbital complications at presentation and older age were the most important determinants of medical treatment failure. Early referral to eye, nose and throat (ENT) should be considered for children >5 years with ARS due to worse orbital complications despite prehospital antibiotics.

A Helicobacter pylori screening and treatment program to eliminate gastric cancer among junior high school students in Saga Prefecture: a preliminary report

BACKGROUND

To present the strategies and preliminary findings of the first 3 years after implementing a Helicobacter pylori screening and eradication program to prevent gastric cancer in Saga Prefecture.

METHODS

A screening and treatment program to eradicate H. pylori from third-grade junior high students was started in Saga Prefecture in 2016, using local governmental grants. Screening was with urinary anti-H. pylori antibody tests, followed by H. pylori stool antigen tests for students who were antibody positive. Those positive on both tests underwent H. pylori eradication by triple therapy based on a potassium-competitive acid blocker.

RESULTS

From 2016 to 2018, the participation rate was 83.1% and the H. pylori infection rate was 3.1% (660/21,042). The participation rates were higher in 2017 (85.4%) and 2018 (85.9%) compared with 2016 (78.5%) (P < 0.0001), and the infection rate also decreased in a time-dependent manner (2016: 3.6%, 2017: 3.3%, 2018: 2.5%, P = 0.0001). In total, 501 students positive for H. pylori received eradication therapy (85.1% success) and adverse events occurred in 20 of these (4.0%). However, no serious complications occurred.

CONCLUSIONS

The H. pylori screening and eradication project for school students in Saga Prefecture has started successfully and we have seen both a steady increase in the participation rate and a steady decrease in the infection rate, without major safety concerns.

Duration of Pediatric Clinical Trials Submitted to the US Food and Drug Administration

Importance

The increasing prevalence of pediatric chronic disease has resulted in increased exposure to long-term drug therapy in children. The duration of recently completed drug trials that support approval for drug therapy in children with chronic diseases has not been systematically evaluated. Such information is a vital first step in forming safety pharmacovigilance strategies for drugs used for long-term therapy in children.

Objective

To characterize the duration of clinical trials submitted to the US Food and Drug Administration (FDA) for pediatric drug approvals, with a focus on drugs used for long-term therapy.

Design and Setting

A review was performed of all safety and efficacy clinical trials conducted under the Best Pharmaceuticals for Children Act or the Pediatric Research Equity Act and submitted to the FDA from September 1, 2007, to December 31, 2014, to support the approval of drugs frequently used for long-term therapy in children. Statistical analysis was performed from July 1, 2015, to December 31, 2017.

Main Outcomes and Measures

Maximum duration of trials submitted to support FDA approval of drugs for children.

Results

A total of 306 trials supporting 86 drugs intended for long-term use in children were eligible for the primary analysis. The drugs most commonly evaluated were for treatment of neurologic (25 [29%]), pulmonary (16 [19%]), and anti-infective (14 [16%]) indications. The median maximum trial duration by drug was 44 weeks (minimum, 1.1 week; maximum, 364 weeks). For nearly two-thirds of the drugs (52 [61%]), the maximum trial duration was less than 52 weeks. For 10 of the drugs (12%), the maximum trial duration was 3 years or more. Maximum duration of trials did not vary by therapeutic category, minimum age of enrollment, calendar year, or legislative mandate.

Conclusions and Relevance

Pediatric clinical trials designed to sufficiently investigate drug safety and efficacy to support FDA approval are of relatively limited duration. Given the potential long-term exposure of patients to these drugs, the clinical community should consider whether new approaches are needed to better understand the safety associated with long-term use of these drugs.

A Population-Based Pharmacokinetic Model Approach to Pantoprazole Dosing for Obese Children and Adolescents

BACKGROUND AND AIMS

Pharmacokinetic data for proton pump inhibitors (PPIs), acid-suppression drugs commonly prescribed to children, are lacking for obese children who are at greatest risk for acid-related disease. In a recent multi-center investigation, we demonstrated decreased, total body weight adjusted, apparent clearance (CL/F) of the PPI pantoprazole for obese children compared with their non-obese peers. Subsequently, we developed a population-based pharmacokinetic (PopPK) model to characterize pantoprazole disposition and evaluated appropriate pantoprazole dosing strategies for obese pediatric patients, using simulation.

METHODS

Pharmacokinetic data from the only prospective study of PPIs in obese children (aged 6-17 years; n = 40) included 273 pantoprazole and 256 pantoprazole-sulfone plasma concentrations, after single oral-dose administration, and were used for pantoprazole model development and covariate analysis (NONMEM®). Model evaluation was performed via bootstrapping and predictive checks, and the final model was applied to simulate systemic pantoprazole exposures for common dosing scenarios.

RESULTS

A two-compartment PopPK model, which included CYP2C19 genotype and total body weight, provided the best fit. Resultant, typical, weight-normalized pantoprazole parameter estimates were different than previously reported for children or adults, with significantly reduced pantoprazole CL/F for obese children. Of the dosing scenarios evaluated, the weight-tiered approach, approved by the US Food and Drug Administration, achieved pantoprazole exposures [area under the curve (AUC0-∞)] within ranges previously reported as therapeutic, without over- or under-prediction for obese children.

CONCLUSIONS

Our data argue against empiric dose escalation of PPIs for obese children and support current FDA-approved pediatric weight-tiered dosing for pantoprazole; however, 3- to 5-fold inter-individual variability in pantoprazole AUC0-∞ remained using this dosing approach.

Diagnosis and treatment of Helicobacter pylori in the pediatric population

Although about 35 years have elapsed since the discovery of the Helicobacter pylori, its diagnosis and the choice of optimal eradication therapy are still to be defined. Over time, there has been an increase in interest, publications, recommendations and guidelines. Moreover, management of the disease in pediatric subjects differs somewhat to that of adults and requires a more delicate approach leading to alternative strategies for both diagnosis and treatment. Which patient should be investigated for H. pylori, when to perform noninvasive or invasive tests, what are the proper therapeutic options and best antibiotics regimen to eradicate the infection are practices changing with evidences through time. Therefore, an updated guideline was published by the European Society of Pediatric Gastroenterology, Hepatology and Nutrition (ESPGHAN) and the North American Society for Pediatric Gastroenterology, Hepatology and Nutrition (NASPGHAN) in 2017. The aim of this review is to highlight what is new and what differs between adult and pediatric population regarding the management of H. pylori infection after the ESPGHAN/NASPGHAN guidelines, enriched with updates from literature reviews published over the last two years.

Proton pump inhibitors: from CYP2C19 pharmacogenetics to precision medicine

Introduction: Proton Pump inhibitors (PPIs) are commonly used for a variety of acid related disorders. Despite the overall effectiveness and safety profile of PPIs, some patients do not respond adequately or develop treatment related adverse events. This variable response among patients is in part due to genotype variability of CYP2C19, the gene encoding the CYP450 (CYP2C19) isoenzyme responsible for PPIs metabolism.

Areas covered: This article provides an overview of the pharmacokinetics and mechanism of action of the currently available PPIs, including the magnitude of CYPC19 contribution to their metabolism. Additionally, the role of CYP2C19 genetic variability in the therapeutic effectiveness or outcomes of PPI therapy is highlighted in details, to provide supporting evidence for the potential value of CYP2C19 genotype-guided approaches to PPI drug therapy.

Expert opinion: There is a large body of evidence describing the impact of CYP2C19 variability on PPIs and its potential role in individualizing PPI therapy, yet, CYP2C19 pharmacogenetics has not been widely implemented into clinical practice. More data are needed but CYP2C19 genotype-guided dosing of PPIs is likely to become increasingly common and is expected to improve clinical outcomes, and minimize side effects related to PPIs.

Obese Children Require Lower Doses of Pantoprazole Than Nonobese Peers to Achieve Equal Systemic Drug Exposures

OBJECTIVE

To assess appropriate pantoprazole dosing for obese children, we conducted a prospective pharmacokinetics (PK) investigation of pantoprazole in obese children, a patient population that is traditionally excluded from clinical trials.

STUDY DESIGN

A total of 41 obese children (6-17 years of age), genotyped for CYP2C19 variants *2, *3, *4, and *17, received a single oral dose of pantoprazole, ~1.2 mg/kg lean body weight (LBW), with LBW calculated via a validated formula. Ten post-dose pantoprazole plasma concentrations were measured, and PK variables generated via noncompartmental methods (WinNonlin). Linear and nonlinear regression analyses and analyses of variance were used to explore obesity, age, and CYP2C19 genotype contribution to pantoprazole PK. PK variables of interest were compared with historic nonobese peers treated with pantoprazole.

RESULTS

Independent of genotype, when normalized to dose per kg total body weight, pantoprazole apparent clearance and apparent volume of distribution were significantly lower (P < .05) and systemic exposure significantly higher (P < .01) in obese vs nonobese children. When normalized per kg LBW, these differences were not evident in children ≥12 years of age and markedly reduced in children <12 years of age.

CONCLUSIONS

LBW dosing of pantoprazole led to pantoprazole PK similar to nonobese peers. Additional factors, other than body size (eg, age-related changes in CYP2C19 activity), appear to affect pantoprazole PK in children <12 years of age.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT02186652.

Non-Specific Gastric Inflammation in Children is Associated with Proton Pump Inhibitor Treatment for More than 6 Weeks

BACKGROUND AND AIMS

Non-specific gastric inflammation (NSGI) is a commonly reported pathological finding. We investigated if it is associated with the use of proton pump inhibitors (PPIs) in children at a single tertiary center.

METHODS

We performed an IRB-approved chart review of all endoscopy and biopsy reports of patients who underwent esophagogastroduodenoscopy between July 2009 and July 2010 (n = 310). Demographic data, dose, duration of exposure to PPI, and biopsy results were collected and analyzed. All esophageal, gastric, and duodenal biopsies were independently reviewed by a pathologist. Patients with acute gastritis, moderate/severe chronic gastric inflammation, or Helicobacter pylori infection were excluded. The presence of NSGI was compared between patients exposed and not exposed to PPI as well as between patients with different doses and durations of PPI exposure to assess for potential associations.

RESULTS

A total of 193 patients were included: 88 (46%) had a history of PPI use and 48 (25%) were found to have NSGI. Compared to patients not exposed to PPI, the odds ratio of NSGI in patients exposed to PPIs was 2.81 (95% CI: 1.36-5.93). The odds ratio of NSGI in patients exposed to PPI for >3 months was 4.53 (95% CI: 1.69-11.97). Gender, ethnicity, and age were not associated with NSGI. No histological differences were found in the esophagus and duodenum between patients exposed and not exposed to PPI.

CONCLUSION

This study found that PPI exposure is associated with NSGI with a higher risk for those exposed for >3 months. As the clinical implications of NSGI are not known, judicious use of PPIs is needed. Prospective studies are required to confirm and to determine the etiologic factors (i.e., alteration of the gastric pH, serum gastrin) that may be related with the presence of NGSI.

A double-blind placebo-controlled randomized trial on probiotics in small bowel bacterial overgrowth in children treated with omeprazole

OBJECTIVE

To evaluate the incidence of small bowel bacterial overgrowth (SBBO) in children treated with omeprazole, and to test whether probiotics influence the incidence.

METHODS

A double-blinded, placebo-controlled trial was performed in 70 children treated orally during four weeks with 20mg omeprazole per day. Lactobacillus rhamnosus R0011 (1.9×10(9) cfu) and Lactobacillus acidophilus R0052 (0.1×10(9) cfu) were simultaneously given daily to 36 subjects (probiotic group), while 34 subjects received placebo (placebo group). The diagnosis of SBBO was based on the development of suggestive symptoms, in combination with a positive glucose breath test.

RESULTS

After one month of proton pump inhibitor (PPI) treatment, 30% (21/70) had a positive breath test suggesting SBBO; of these 62% were symptomatic. Five children developed SBBO-like symptoms, but had a negative breath test; and 44 (63%) were symptom free and had a negative breath test. There was no difference in the incidence of positive breath tests in the probiotic versus the placebo group (33% vs 26.5%; p=0.13).

CONCLUSIONS

Since symptoms suggesting SBBO developed in 26% of PPI-treated children, and since the glucose breath test was abnormal in 72% of these, this side-effect should be more frequently considered. The probiotic tested did not decrease the risk to develop SBBO.

Gastroesophageal reflux in critically ill children: a review

Gastroesophageal reflux (GER) is very common in children due to immaturity of the antireflux barrier. In critically ill patients there is also a high incidence due to a partial or complete loss of pressure of the lower esophageal sphincter though other factors, such as the use of nasogastric tubes, treatment with adrenergic agonists, bronchodilators, or opiates and mechanical ventilation, can further increase the risk of GER. Vomiting and regurgitation are the most common manifestations in infants and are considered pathological when they have repercussions on the nutritional status. In critically ill children, damage to the esophageal mucosa predisposes to digestive tract hemorrhage and nosocomial pneumonia secondary to repeated microaspiration. GER is mainly alkaline in children, as is also the case in critically ill pediatric patients. pH-metry combined with multichannel intraluminal impedance is therefore the technique of choice for diagnosis. The proton pump inhibitors are the drugs of choice for the treatment of GER because they have a greater effect, longer duration of action, and a good safety profile.

Proton pump inhibitors in pediatrics : mechanism of action, pharmacokinetics, pharmacogenetics, and pharmacodynamics

Proton pump inhibitors (PPIs) have become some of the most frequently prescribed medications for treatment of adults and children. Their effectiveness for treatment of peptic conditions in the pediatric population, including gastric ulcers, gastroesophageal reflux disease (GERD), and Helicobacter pylori infections has been established for children older than 1 year. Studies of the preverbal population of neonates and infants have identified doses that inhibit acid production, but the effectiveness of PPIs in the treatment of GERD has not been established except for the recent approval of esomeprazole treatment of erosive esophagitis in infants. Reasons that have been proposed for this are complex, ranging from GERD not occurring in this population to a lack of histologic identification of esophagitis related to GERD to questions about the validity of symptom scoring systems to identify esophagitis when it occurs in infants. The effectiveness of PPIs relates to their structures, which must undergo acidic activation within the parietal cell to allow the PPI to be ionized and form covalent disulfide bonds with cysteines of the H(+)-K(+)-adenosine triphosphatase (H(+)-K(+)-ATPase). Once the PPI binds to the proton pump, the pump is inactivated. Some PPIs, such as omeprazole and rabeprazole bind to cysteines that are exposed, and their binding can be reversed. After irreversible chemical inhibition of the proton pump, such as occurs with pantoprazole, the recovery of the protein of the pump has a half-life of around 50 h. Cytochrome P450 (CYP) 2C19 and to a lesser degree CYP3A4 clear the PPIs metabolically. These enzymes are immature at birth and reach adult levels of activity by 5-6 months after birth. This parallels studies of the maturation of CYP2C19 to adult levels by roughly the same age after birth. Specific single nucleotide polymorphisms of CYP2C19 reduce clearance proportionally and increase exposure and prolong proton pump inhibition. Prolonged treatment of pediatric patients with PPIs has not caused cancer or significant abnormalities.

[Hemodynamic effects of intravenous omeprazole in critically ill children]

INTRODUCTION

Critical patients usually have hemodynamic disturbances which may become worse by the administration of some drugs. Omeprazole is a drug used in the prophylaxis of the gastrointestinal bleeding in these patients, but its cardiovascular effects are unknown. The objective was to study the hemodynamic changes produced by intravenous omeprazole in critically ill children and to find out if there are differences between two different doses of omeprazole.

MATERIAL AND METHODS

A randomized prospective observational study was performed on 37 critically ill children aged from 1 month to 14 years of age who required prophylaxis for gastrointestinal bleeding. Of these, 19 received intravenous omeprazole 0.5mg/kg every 12 hours, and 18 received intravenous omeprazole 1mg/kg every 12 hours. Intravenous omeprazole was administered in 20 minutes by continuous infusion pump. Heart rate, systolic, diastolic and mean arterial blood pressure, central venous pressure and ECG were recorded at baseline, and at 15, 30, 60 and 120 minutes of the infusion.

RESULTS

There were no significant changes in the electrocardiogram, heart rate, blood pressure and central venous pressure. No patients required inotropic therapy modification. There were no differences between the two doses of omeprazole.

CONCLUSIONS

Intravenous omeprazole administration of 0.5mg/kg and 1mg/kg is a hemodynamically safe drug in critically ill children.

Chronic rhinosinusitis in children

Rhinosinusitis is a very common disease worldwide and specifically in the US population. It is a common disease in children but may be underdiagnosed. Several reasons may account to the disease being missed in children. The symptoms in children are limited and can be very similar to the common cold or allergic symptoms. Cough and nasal discharge may be the only symptoms present in children. A high index of suspicion is necessary to make the diagnosis of rhinosinusitis in these children. The majority of those children are treated medically. Only a few number will require surgical intervention when medical treatment fails. Complications of rhinosinusitis, even though rare, can carry a high morbidity and mortality rate.

Toxicology and toxicokinetics of oral pantoprazole in neonatal and juvenile dogs

BACKGROUND

Pantoprazole is an irreversible inhibitor of H(+) /K(+) adenosine triphosphatase proton pump. This study encompassed the period of postnatal stomach development to determine whether immature animals are uniquely sensitive to progression of PPI-induced enterochromaffin-like cell hyperplasia.

METHODS

Pantoprazole was administered to beagle dogs at 3, 10, or 30 mg/kg/day (10/sex/group) from PND 1 for 13 weeks, subsets of animals had a 13-week recovery period. Clinical signs, body weights, growth, clinical chemistry, and neurobehavioral endpoints were assessed. Selected organs were weighed and histologically examined.

RESULTS

There were no effects on body weights, growth, landmarks of physical and reproductive development, or sensory and neurobehavioral function. Cholesterol and triglyceride levels were increased at 10 and 30 mg/kg/day, but resolved during the recovery period. Stomach weight was increased at all doses, but after recovery the differences in stomach weights resolved for females although male stomach weights remained slightly increased. Pantoprazole-related microscopic findings in the stomach consisted of increased mucosal height, glandular necrosis, and glandular dilation at all doses; and ECL cell hyperplasia, parietal cell vacuolation, and atrophy of chief cells are noted at 10 and/or 30 mg/kg/day. There was a partial recovery of these microscopic changes indicated by a decreased incidence and/or severity of increased mucosal height, glandular necrosis, ECL cell hyperplasia, and chief cell atrophy, and complete resolution of other microscopic observations.

CONCLUSION

Pantoprazole administered to beagles from PND 1 for 13 weeks resulted in findings similar to those in adult dogs and juvenile dogs, which showed no increase in severity or progression of ECL hyperplasia.

Pantoprazole: a proton pump inhibitor

Pantoprazole is a proton pump inhibitor (PPI) that binds irreversibly and specifically to the proton pump, thereby reducing gastric acid secretion. Pantoprazole has a relatively long duration of action compared with other PPIs, and a lower propensity to become activated in slightly acidic body compartments. To date, no drug-drug interactions have been identified with pantoprazole in numerous interaction studies. Overall, in the short-term (8-10 weeks) initial treatment of gastro-oesophageal reflux disease (a condition that occurs when the reflux of gastric contents causes troublesome symptoms and/or complications) and long-term (6-24 months) maintenance therapy, oral pantoprazole 20 or 40 mg/day demonstrated similar efficacy to omeprazole, lansoprazole and esomeprazole and greater efficacy than histamine type 2 receptor antagonists. Pantoprazole is also effective in treating and preventing NSAID-related gastric and gastroduodenal injury. The optimal adult oral dose for gastric acid-related disorders is pantoprazole 40 mg once daily. Although data are limited, pantoprazole 20 or 40 mg/day was effective and well tolerated in the treatment of acid-related disorders in children and adolescents. Pantoprazole was also well tolerated in adults with acid-related disorders in short- and long-term studies. Thus, pantoprazole is a valuable agent for the management of acid-related disorders.

Pharmacokinetics of intravenous omeprazole in critically ill paediatric patients

The proton pump inhibitors are first-line drugs for the treatment of a number of gastrointestinal diseases. These drugs have a good safety profile, making it possible to use them in paediatric patients. Although their pharmacokinetics in children has not been extensively studied, research performed suggests that the dose used should be varied as a function of age, as this factor affects the drug's metabolism. Proton pump inhibitors can be used in critically ill children for the prophylaxis and treatment of gastrointestinal haemorrhage, although there is still little experience with this. The most widely used proton pump inhibitor at the present time is omeprazole. As there are specific characteristics of these patients that could alter the pharmacokinetics of the drugs, studies need to be performed to determine the most suitable dose and dosage interval.

Regurgitation in healthy and non healthy infants

Uncomplicate regurgitation in otherwise healthy infants is not a disease. It consists of milk flow from mouth during or after feeding. Common causes include overfeeding, air swallowed during feeding, crying or coughing; physical exam is normal and weight gain is adequate. History and physical exam are diagnostic, and conservative therapy is recommended. Pathologic gastroesophageal reflux or gastroesophageal reflux disease refers to infants with regurgitation and vomiting associated with poor weight gain, respiratory symptoms, esophagitis. Reflux episodes occur most often during transient relaxations of the lower esophageal sphincter unaccompanied by swallowing, which permit gastric content to flow into the esophagus. A minor proportion of reflux episodes occurs when the lower esophageal sphincter fails to increase pressure during a sudden increase in intraabdominal pressure or when lower esophageal sphincter resting pressure is chronically reduced. Alterations in several protective mechanisms allow physiologic reflux to become gastroesophageal reflux disease; diagnostic approach is both clinical and instrumental: radiological series are useful to exclude anatomic abnormalities; pH-testing evaluates the quantity, frequency and duration of the acid reflux episodes; endoscopy and biopsy are performed in the case of esophagitis. Therapy with H2 receptor antagonists and proton pump inhibitors are suggested.

Current pharmacological management of gastro-esophageal reflux in children: an evidence-based systematic review

Gastro-esophageal reflux (GER) is a common phenomenon, characterized by the regurgitation of the gastric contents into the esophagus. Gastro-esophageal reflux disease (GERD) is the term applied when GER is associated with sequelae or faltering growth. The main aims of treatment are to alleviate symptoms, promote normal growth, and prevent complications. Medical treatments for children include (i) altering the viscosity of the feeds with alginates; (ii) altering the gastric pH with antacids, histamine H(2) receptor antagonists, and proton pump inhibitors; and (iii) altering the motility of the gut with prokinetics, such as metoclopramide and domperidone. Our aim was to systematically review the evidence base for the medical treatment of gastro-oesophageal reflux in children. We searched PubMed, AdisOnline, MEDLINE, and EMBASE, and then manually searched reviews from the past 5 years using the key words 'gastro-esophageal' (or 'gastroesophageal'), 'reflux', 'esophagitis', and 'child$' (or 'infant') and 'drug$' or 'therapy'. Articles included were in English and had an abstract. We used the levels of evidence adopted by the Centre for Evidence-Based Medicine in Oxford to assess the studies for all reported outcomes that were meaningful to clinicians making decisions about treatment. This included the impact of clinical symptoms, pH study profile, and esophageal appearance at endoscopy. Five hundred and eight articles were reviewed, of which 56 papers were original, relevant clinical trials. These were assessed further. Many of the studies considered had significant methodological flaws, although based on available evidence the following statements can be made. For infant GERD, ranitidine and omeprazole and probably lansoprazole are safe and effective medications, which promote symptomatic relief, and endoscopic and histological healing of esophagitis. Gaviscon(R) Infant sachets are safe and can improve symptoms of reflux. There is less evidence to support the use of domperidone or metoclopramide. More evidence is needed before other anti-reflux medications can be recommended. For older children, acid suppression is the mainstay of treatment. The largest evidence base supports the early use of H(2) receptor antagonists or proton pump inhibitors.

Proton pump inhibitors: actions and reactions

Proton pump inhibitors are the second most commonly prescribed drug class in the United States. The increased utilization of PPIs parallels the rising incidence of reflux disease. Owing to their clinical efficacy and relative lack of tachyphylaxis, PPIs have largely displaced H-2 receptor antagonists in the treatment of acid peptic disorders. The elevation of intragastric pH and subsequent alterations of gastric physiology induced by PPIs may yield undesired effects within the upper GI tract. The ubiquity of the various types of H(+), K(+)-ATPase could also contribute to non-gastric effects. PPIs may influence physiology in other ways, such as inducing transepithelial leak.

Paranasal sinuses and middle ear infections: what do they have in common?

Otitis media and sinusitis are among the most common pediatric diseases and they share common features. Although the anatomy, physiology and disease processes are not identical, knowledge of the pathophysiology of middle ear disorders often provides to the pediatrician a useful understanding of sinus diseases. The same risk factors identified for otitis media may play a pivotal role in the development of sinusitis. Moreover, as both paranasal sinuses and middle ear acquire respiratory pathogens from nasopharynx, acute sinusitis is usually caused by the same bacterial pathogens that cause acute otitis media, with a major role for Streptococcus pneumoniae, Haemophilus influenzae and Moraxella catarrhalis, while anaerobes may predominate in chronic disease. A responsibility of bacterial biofilms in chronic sinusitis, similarly to otitis media, has been recently suggested. Biofilms, three-dimensional aggregates of bacteria, are refractory to antibiotics and thus might explain why some patients improve while on antibiotics but relapse after completion of therapy.

Systemic treatment of rhinosinusitis in children

Systemic acute rhinosinusitis therapy consists mostly of antibiotic treatment because pathogens play a major role. Amoxicillin is the drug of choice for treatment of acute rhinosinusitis, with second- and third- generation cephalosporins, azythromycin, clarithromycin, and telithromycin as possible options, especially in the case of allergy to amoxicillin. If the clinical course suggests that an anaerobic pathogen is more likely, clindamycin or metronidazole can be considered in combination with a broad-spectrum drug. In antimicrobial treatment of chronic sinusitis there is no consensus on treatment length, organism coverage, or which antibiotics are most effective because the bacteriology is variable with polymicrobial anaerobic and aerobic organisms present. Adjuvant therapies need to be proven by additional studies. Chronic rhinosinusitis is heterogeneous and treatment should vary according to the causative factor involved. Short courses of systemic steroids have been found very useful to decrease mucosal swelling and inflammation in chronic rhinosinusitis. However, no randomized controlled studies have been performed to validate their efficacy in children. A variety of other agents are used in the treatment of chronic rhinosinusitis including antihistamines, decongestants, and leukotriene modifiers. To date, there is no good evidence from randomized controlled studies to support the use of any of these agents in the treatment of this disease in either children or adults.

Recurrent croup presentation, diagnosis, and management

PURPOSE

The lack of clinical insight into recurrent croup often leads to underdiagnosis of an upper airway lesion, and subsequently, inadequate treatment. This study examined the underlying etiology, diagnosis, treatment, and clinical outcome of patients with a history of recurrent croup identified at initial presentation. The aim was to present common diagnostic features and suggest new diagnostic and management recommendations.

MATERIALS AND METHODS

A retrospective chart review of 17 children diagnosed with recurrent croup. Demographic, historical, and intraoperative data as noted in clinic charts were collected. Specific collected data included age, sex, chief complaint, presenting symptoms, past medical history, previous medication history, number of emergency room visits and inpatient admissions, tests/procedures performed and corresponding findings, current treatment given, and posttreatment clinical outcome.

RESULTS

Six (35.3%) patients presented initially with a past medical history of gastroesophageal reflux disease. Fourteen (82.3%) patients had positive endoscopic evidence of gastroesophageal reflux. For these 14 patients, 44 laryngopharyngeal reflux lesions were noted, with 32 (72.7%) occurring in the subglottis. All 14 patients demonstrated various degrees of subglottic stenosis ranging from 30% to 70% (Cotton-Myer grade I-II). All 17 patients (100%) demonstrated subglottic stenosis ranging from 15% to 70% airway narrowing.

CONCLUSIONS

History suggestive of recurrent croup requires close monitoring and expedient direct laryngoscopy/bronchoscopy for diagnosis. Long-term follow-up and antireflux treatment are necessary as well as endoscopic documentation of significant reflux resolution.

Knowledge, attitudes and practice styles of North American pediatricians regarding gastroesophageal reflux disease

BACKGROUND

The North American Society for Pediatric Gastroenterology, Hepatology and Nutrition launched a provider and public education campaign in 2002 to raise awareness of gastroesophageal reflux disease (GERD). To determine the effectiveness of campaign messages, we conducted a knowledge, attitudes, and practice styles (KAPS) survey of pediatric providers. Understanding the spectrum of management styles of GERD in children is critical to achieve better health outcomes and reduce health care costs.

MATERIALS AND METHODS

The KAPS questionnaire was administered to 6000 randomly selected members of the American Academy of Pediatrics.

RESULTS

A total of 1245 members responded; 82% worked in a primary care setting and 18% in subspecialty practices. Overall, 66% of the members order diagnostic testing in routine practice, 54% start testing for GERD in neonates, and 38% start testing after 1 month of age. The most common tests ordered were barium esophagram (45%) and esophageal pH monitoring (37%). GERD treatment with acid suppression before ordering diagnostic testing was a choice of 82% of the respondents. However, 19% believed acid suppression was best achieved by H2 blockers. If acid suppression was indicated, then only 36% followed guideline recommendations for therapy duration and 52% followed guideline recommendations for dosing. Antireflux surgery was recommended only as a last resort by 92%. Overall, 69% of providers believed the amount of GERD-related information available was not enough. Respondents who were not aware of available GERD practice guidelines ranged from 74% to 92%.

CONCLUSIONS

Pediatric providers appear to frequently order diagnostic testing and treatment for GERD, yet knowledge about evidence-based GERD management among this random sample appeared limited. Moreover, a significant number of providers were not aware of different guideline publications.

[Safety of proton pump inhibitors]

The significant inhibitory capacity of gastric acid secretion of PPIs makes them the drugs of choice for treating acid-related diseases. The considerable prevalence of these diseases and the need for maintaining the administration of the drug during considerably long periods results in this therapeutic group being one of the most widely used. However, in spite of their extensive use, there continue to emerge concerns about their potential toxicity; concerns surrounding the specificity of their mechanism of action and a consequential suspicion that something so potent must involve harmful effects. PPIs act selectively on the final stage of the process of gastric acid secretion, namely the H+/K+-ATPase or proton pump. This enzyme represents an essential step in the process of secretion of H+, and PPIs exert a very specific action on the parietal cell, as they need an environment with very low pH levels, which only exist in this cell. In the present article, the adverse effects of PPIs are reviewed, with special emphasis on those related to their continued administration and on the special circumstances of patients, as in the case of the elderly, those with liver failure, pregnant and breastfeeding mothers and children. All the PPIs on the market share a common chemical basis and there are no great differences in their potential adverse effects, the possibility of them promoting opportunist infections or their capacity to generate pharmacokinetic interactions with other drugs, which, if occur, are generally insignificant. After two decades of use, PPIs have proved to be very effective and safe drugs.

Pediatric surgeons and gastroesophageal reflux

BACKGROUND/AIMS

Better antacid medications and the introduction of laparoscopy destabilize the indications for fundoplication. This study aims at raising a discussion among pediatric surgeons on these indications, modalities, and the results of this operation.

MATERIALS AND METHODS

A total of 252 refluxing children operated between 1992 and 2006 were divided into groups according to predominant symptoms (93 digestive, 47 respiratory, and 68 neurologic) or to comorbidities (27 esophageal atresia, 10 diaphragmatic hernia, 5 abdominal wall defects, and 2 caustic stricture), and the indications, complications, mortality, and long-term results were reviewed. Features of open (n = 135) and laparoscopic (n = 117) approaches were compared, and long-term integrity of the wrap was analyzed using the Kaplan-Meier method.

RESULTS

Digestive, respiratory, and neurologic patients had more often laparoscopic plications, whereas all others rather had an open approach. The rate of complications was 22%, and they were more frequent in children operated by laparotomy (P < .05). Median follow up was 51.3 months (range, 6-160). Overall wrap integrity was maintained in 89% of the children, and the proportions for digestive, respiratory, and neurologic groups were 95%, 95%, and 87%, respectively. For esophageal atresia, congenital diaphragmatic hernia, abdominal wall defects, and caustic stricture, they were 72%, 77%, 100%, and 0%, respectively. The functional results were fully satisfactory in 83% of patients. There were 17 deaths (6.7%), but only 3 in the first postoperative month and only 1 related to the operation (0.4%).

CONCLUSIONS

Fundoplication is a powerful method of reflux control. It is indicated after failure of medical treatment in gastroesophageal reflux disease and in symptomatic refluxers with some particular comorbidities. Surgery should be offered only after diagnosis has been firmly established, and the indications must remain identical for open and laparoscopic procedures. High technical standards and rigorous report of the results are required for keeping a relevant place of pediatric surgery in the treatment of this disease.

Effect of a probiotic food as an adjuvant to triple therapy for eradication of Helicobacter pylori infection in children

OBJECTIVE

Current recommendations for treatment of Helicobacter pylori infection include a proton pump inhibitor in combination with two antibiotics. We evaluated the potential activity of a probiotic food as an adjuvant to antibiotic triple therapy for eradication of H. pylori infection in children from Buenos Aires, Argentina.

METHODS

Sixty-five children who tested positive for H. pylori, as diagnosed by (13)C-urea breath test and endoscopy, were included in this study. Patients were randomized to receive 1-wk triple therapy plus probiotic food (treated group) or milk placebo (control) that was administered for 3 mo. Probiotic food consisted of 250 mL of a commercial yogurt containing Bifidobacterium animalis and Lactobacillus casei (10(7) colony-forming units/mL). Post-treatment urea breath test controls were performed 1 and 3 mo after the end of triple therapy.

RESULTS

We found no significant differences in H. pylori eradication rates (ERs) at 1 and 3 mo between the treated group (ER = 45.5% and 42.4%) and the control group (ER = 37.5% and 40.6%). Relative risks between groups were 0.87 (95% confidence interval 0.58-1.32, P = 0.345) in the first month and 0.97 (95% confidence interval 0.64-1.46, P = 0.542) in the third month.

CONCLUSIONS

We could not demonstrate an adjuvant effect of the studied probiotic food to triple therapy in the eradication of H. pylori infection in children in Buenos Aires, Argentina. However, we found lower ERs than those reported for the same therapeutic scheme in developed countries, indicating that bacterial resistance and alternative therapeutic strategies should be studied.

Multicenter, randomized, double-blind study comparing 10, 20 and 40 mg pantoprazole in children (5-11 years) with symptomatic gastroesophageal reflux disease

OBJECTIVE

To evaluate symptom improvement in 53 children (aged 5-11 years) with endoscopically proven gastroesophageal reflux disease (GERD) treated with pantoprazole (10, 20 and 40 mg) using the GERD Assessment of Symptoms in Pediatrics Questionnaire.

METHODS

The GERD Assessment of Symptoms in Pediatrics Questionnaire was used to measure the frequency and severity over the previous 7 days of abdominal/belly pain, chest pain/heartburn, difficulty swallowing, nausea, vomiting/regurgitation, burping/belching, choking when eating and pain after eating. Individual symptom scores were based on the product of the frequency and usual severity of each symptom. The sum of the individual symptom score values made up the composite symptom score (CSS). The primary end point was the change in the mean CSS from baseline to week 8.

RESULTS

Mean frequency and severity of each symptom significantly decreased (from P < 0.006 to P < 0.001) over time. Similar significant decreases in CSS at week 8 versus baseline (P < 0.001) were seen in all groups. Significant decreases from baseline in CSS were noted from weeks 1 to 8 in the 20-mg (P < 0.003) and 40-mg (P < 0.001) groups. The 20- and 40-mg doses were significantly (P < 0.05) more effective than the 10-mg dose in improving GERD symptoms at week 1. Adverse events were similar among the treatment groups.

CONCLUSIONS

Pantoprazole (20 and 40 mg) is effective in reducing endoscopically proven GERD symptoms in children. Both 20 and 40 mg pantoprazole significantly reduced symptoms as early as 1 week.

Safety of potent gastric acid inhibition

The proton pump inhibitors are a very effective drug group for the control of gastric acid secretion, which makes them of great use in the medical practice setting, while at the same time they represent one of the treatment groups widely used in Western European countries. These factors lead to this drug group being prescribed in all age populations, quite often in polymedicated patients and with pluripathology, and on many occasions during prolonged periods of time. All these determinant factors sometimes make the safety profile of proton pump inhibitors disputable. In this respect all of them have been shown to have little adverse events and are safe in long-term treatment. The risk of drug interactions when prescribed in association with other drugs is low and their repercussion in the medical practice setting is quite exceptional as they require few dosage adjustments in patients with severe concomitant diseases and in elderly patients. Finally, their safety is high in pregnant women and in children, although further studies in this population are required to corroborate this evidence.

Gastroesophageal reflux

Gastroesophageal reflux disease (GERD) is the most common disease of the gastrointestinal system. Heartburn, regurgitation, and dysphagia are the most common symptoms of GERD. However, chest pain, chronic cough, laryngitis, hoarseness, and other otolaryngologic manifestation can be the primary manifestations of the disease. Endoscopy, barium studies, and especially pH monitoring and therapeutic trials may help in establishing the diagnosis of GERD. The introduction of H2 antagonists and especially of proton pump inhibitors (PPI) has brought symptomatic relief in most patients. However, surgical procedures, especially laparoscopic fundoplication, are still required in some patients. Barrett's esophagitis is the most common complication of GERD and is associated with a high prevalence of esophageal adenocarcinoma. Whether or not treatment with either PPIs or H2 antagonists can prevent this complication is still under investigation.

Acid suppression does not change respiratory symptoms in children with asthma and gastro-oesophageal reflux disease

BACKGROUND

Epidemiological studies have shown an association between gastro-oesophageal reflux disease (GORD) and asthma, and oesophageal acid perfusion may cause bronchial constriction. However, no causative relation has been proven.

AIM

To assess whether acid suppression would lead to reduced asthma symptoms in children with concomitant asthma and GORD.

METHODS

Thirty eight children (mean age 10.8 years, range 7.2-16.8; 29 males) with asthma and a reflux index > or =5.0 assessed by 24 hour oesophageal pH monitoring were randomised to 12 weeks of treatment with omeprazole 20 mg daily or placebo. The groups were similar in age, gender, mean reflux index, and asthma severity. Primary endpoints were asthma symptoms (daytime wheeze, symptoms at night, in the morning, and during exercise) and quality of life (PAQLQ). Secondary endpoints were changes in lung function and the use of short acting bronchodilators. At the end of the study a repeated pH study was performed to confirm the efficacy of acid suppression.

RESULTS

The change in total symptom score did not differ significantly between the omeprazole and the placebo group, and decreased by 1.28 (95% CI -0.1 to 2.65) and 1.28 (95% CI -0.72 to 3.27) respectively. The PAQLQ score increased by 0.62 (95% CI 0.29 to 0.95) in the omeprazole group compared to 0.50 (95% CI 0.29 to 0.70) in the placebo group. Change in lung function and use of short acting bronchodilators were similar in the groups. The acid suppression was adequate (reflux index <5.0) under omeprazole treatment.

CONCLUSION

Omeprazole treatment did not improve asthma symptoms or lung function in children with asthma and GORD.

Pharmacokinetics of proton pump inhibitors in children

The use of proton pump inhibitors (PPIs) has become widespread in children and infants for the management of paediatric acid-related disease. Pharmacokinetic profiles of only omeprazole and lansoprazole have been well characterised in children over 2 years of age with acid-related diseases. Few data have been recently published regarding the pharmacokinetics of pantoprazole in children, and none are available for rabeprazole or esomeprazole. The metabolism of PPI enantiomers has never been studied in the paediatric population. A one-compartment model best describes the pharmacokinetic behaviour of omeprazole, lansoprazole and pantoprazole in children, with important interindividual variability for each pharmacokinetic parameter. Like adults, PPIs are rapidly absorbed in children following oral administration; the mean time to reach maximum plasma concentration varies from 1 to 3 hours. Since these agents are acid labile, their oral formulations consist of capsules containing enteric-coated granules. No liquid formulation is available for any of the PPIs. Thus, for those patients unable to swallow capsules, extemporaneous liquid preparations for omeprazole and lansoprazole have been reported; however, neither the absolute nor the relative bioavailabilities of these oral formulations have been studied in children. Intravenous formulations are available for omeprazole (in Europe), lansoprazole and pantoprazole. PPIs are rapidly metabolised in children, with short elimination half-lives of around 1 hour, similar to that reported for adults. All PPIs are extensively metabolised by the liver, primarily by cytochrome P450 (CYP) isoforms CYP2C19 and CYP3A4, to inactive metabolites, with little unchanged drug excreted in the urine. Similar to that seen in adults, the absolute bioavailability of omeprazole increases with repeated dosing in children; this phenomenon is thought to be due to a combination of decreased first-pass elimination and reduced systemic clearance. The apparent clearance (CL/F) of omeprazole, lansoprazole and pantoprazole appears to be faster for children than for adults. A higher metabolic capacity in children as well as differences in the extent of PPI bioavailability are most likely responsible for this finding. This may partly account for the need in children for variable and sometimes considerably greater doses of PPIs, on a per kilogram basis, than for adults to achieve similar plasma concentrations. Furthermore, no studies have been able to demonstrate a statistically significant correlation between age and pharmacokinetic parameters among children. Despite the small number of very young infants studied, there is some evidence for reduced PPI metabolism in newborns. The limited paediatric data regarding the impact of CYP2C19 genetic polymorphism on PPI metabolism are similar to those reported for adults, with poor metabolisers having 6- to 10-fold higher area under the concentration-time curve values compared with extensive metabolisers. Finally, because a pharmacokinetic/pharmacodynamic relationship exists for PPIs, the significant interindividual variability in their disposition may partly explain the wide range of therapeutic doses used in children. Further studies are needed to better define the pharmacokinetics of PPIs in children <2 years of age.