The association of erythromycin and infantile hypertrophic pyloric stenosis: causal or coincidental?

Guidelines of the Italian Society of Videosurgery (SIVI) in Infancy for the minimally invasive treatment of Hypertrophic Pyloric Stenosis in neonates and infants

The most appropriate treatment for the infantile Hypertrophic Pyloric Stenosis (HPS) is still debated. The non-surgical conservative treatment with oral or intravenous administration of atropine does not enjoy a widespread appreciation for several factors (...).

Erythromycin and Reflux Events in Premature Neonates: A Randomized Clinical Trial

OBJECTIVE

Gastroesophageal reflux disease (GERD) in premature neonates may manifest as apnea, bradycardia, growth failure, aspiration, or feeding intolerance. Erythromycin ethylsuccinate (EES), is often used as a pro-kinetic in the management of GERD, despite lack of evidence or safety from randomized controlled trials. We sought to study the efficacy of enteral EES at a dose of 50 mg · kg · day in decreasing the frequency of gastroesophageal reflux events as determined by pH-multichannel intraluminal impedance (pH-MII) monitoring.

METHODS

In a randomized, double-blind, placebo-controlled trial, eligible premature neonates with clinical signs of GERD underwent 24-hour pH-MII monitoring. If >5 reflux events were identified on pH-MII, then subjects were randomized to receive either EES or placebo. Repeat 24-hour pH-MII was performed on day 7 of study treatment and compared to initial pH-MII.

RESULTS

Forty-three premature neonates were enrolled. Of those, 31 neonates were randomized, 15 to EES and 16 to placebo with a median (IQR) pretreatment total reflux events per 24 hours of 23 (16-40) and 29 (12-40), respectively. Day 7 total events per 24 hours decreased by 4 events in the EES group to 19 (15-33) and by 10 events in the placebo group to 19 (11-26) (P = 0.09). There were no differences in pretreatment and day 7 acidic and nonacidic reflux, proximal reflux, total or percent reflux time, median or longest bolus clearance time, or nurse-reported apnea events between groups.

CONCLUSIONS

Enteral EES did not decrease reflux events on 24-hour pH-MII at the dose studied. Therefore, it may be ineffective in the treatment of GERD in premature neonates.

Fetal safety of macrolides

Macrolide antibiotics are largely used in pregnancy for different bacterial infections. Their fetal safety has been studied by several groups, yielding opposing results. In particular, there have been studies claiming an association between macrolides and cardiovascular malformations. Exposure in early infancy has been associated with pyloric stenosis and intussusception. This has led to an avoidance in prescribing macrolides to pregnant women in several Scandinavian countries. The Objectives of the present study was to investigate the fetal safety of this class of drug by linking a large administrative database of drug dispensing and pregnancy outcome in Southern Israel. A computerized database of medications dispensed from 1999 to 2009 to all women registered in the Clalit health maintenance organization in southern Israel was linked with two computerized databases containing maternal and infant hospitalization records. Also, medical pregnancy termination data were analyzed. The following confounders were controlled for: maternal age, ethnicity, maternal pregestational diabetes, parity, and the year the mother gave birth or went through medical pregnancy termination. First- and third-trimester exposures to macrolide antibiotics as a group and to individual drugs were analyzed. During the study period there were 105,492 pregnancies among Clalit women that met the inclusion criteria. Of these, 104,380 ended in live births or dead fetuses and 1,112 in abortion due to medical reasons. In the first trimester of pregnancy, 1,033 women were exposed to macrolides. There was no association between macrolides and either major malformations [odds ratio (OR), 1.08; 95% confidence interval (CI), 0.84 to 1.38)] or specific malformations, after accounting for maternal age, parity, ethnicity, prepregnancy diabetes, and year of exposure. During the third trimester of pregnancy, 959 women were exposed to macrolides. There was no association between such exposure and perinatal mortality, low birth weight, low Apgar score, or preterm delivery. Similarly, no associations were demonstrated with pyloric stenosis or intussusception. Use of macrolides in the first trimester of pregnancy is not associated with an increased risk of major malformations. Exposure in the third trimester is not likely to increase neonatal risks for pyloric stenosis or intussusception in a clinically meaningful manner.

Efficacy of intermediate-dose oral erythromycin on very low birth weight infants with feeding intolerance

BACKGROUND

Erythromycin is generally used as a prokinetic agent for the treatment of feeding intolerance in preterm infants; however, results from previous studies significantly vary due to different medication dosages, routes of administration, and therapy durations. The effectiveness and safety of intermediate-dose oral erythromycin in very low birth weight (VLBW) infants with feeding intolerance was examined in this study.

METHODS

Between November 2007 and August 2009, 45 VLBW infants with feeding intolerance, who were all at least 14 days old, were randomly allocated to a treatment group and administered 5mg/kg oral erythromycin every 6hours for 14 days (n=19). Another set of randomly selected infants was allocated to the control group, which was not administered erythromycin (n=26).

RESULTS

The number of days required to achieve full enteral feeding (36.5±7.4 vs. 54.7±23.3 days, respectively; p=0.01), the duration of parenteral nutrition (p<0.05), and the time required to achieve a body weight ≥2500g (p<0.05) were significantly shorter in the erythromycin group compared with the control group. The incidence of parenteral nutrition-associated cholestasis (PNAC) and necrotizing enterocolitis (NEC) ≥ stage II after 14 days of treatment were significantly lower (p<0.05) in the erythromycin group. No significant differences were observed in terms of the incidences of sepsis, bronchopulmonary dysplasia, or retinopathy of prematurity. No adverse effects were associated with erythromycin treatment.

CONCLUSIONS

Intermediate-dose oral erythromycin is effective and safe for the treatment of feeding intolerance in VLBW infants. The incidences of PNAC and ≥ stage II NEC were significant lower in the erythromycin group.

The safety of macrolides during lactation

BACKGROUND

Infantile exposure to macrolides has been associated with hypertrophic pyloric stenosis causing projectile vomiting, dehydration, electrolyte abnormalities, and in rare cases death possibly via macrolide interaction with gastric motilin receptors. Large population-based cohorts have suggested that exposure to macrolides via breastmilk may be associated with pyloric stenosis.

METHODS

In this prospective, controlled observational study designed to assess the safety of macrolides during lactation, we followed infants whose mothers contacted our Drug Consultation Center at the Assaf Harofeh Medical Center (Zerrifin, Israel) inquiring about safety of macrolides during lactation and compared them to a cohort of infants exposed to amoxicillin during breastfeeding.

RESULTS

Fifty-five infants exposed to macrolide antibiotics were compared to a control cohort of 36 infants exposed to amoxicillin via lactation. The infants in the macrolide group were all exposed to erythromycin and the newer macrolides: azithromycin, clarithromycin, and roxithromycin. The rate of adverse reactions the infant experienced while being exposed to both antibiotics was comparable. Seven (12.7%) infants in the macrolide group experienced adverse reactions versus three infants (8.3%) in the amoxicillin group (odds ratio = 1.6, 95% confidence interval, 0.38-6.65, p = 0.73). The adverse reactions in the infants exposed to macrolides were rash, diarrhea, loss of appetite, and somnolence, whereas the infants exposed to amoxicillin experienced rashes and somnolence. Factors such as gestational age, age and weight at exposure, maternal age, or type of macrolide were not associated with the infant's adverse reaction in multivariate regression analysis.

CONCLUSIONS

Rates and types of minor adverse reactions in breastfed infants exposed to a macrolide or amoxicillin in breastmilk were comparable. Macrolide exposure during breastfeeding was not associated with pyloric stenosis, although larger prospective studies are required to confirm our observation.

Infantile hypertrophic pyloric stenosis in infants treated with azithromycin

Seven-week-old 32-week premature triplets were hospitalized because of rhinorrhea, cough with color change and posttussive emesis. One infant had a positive direct fluorescent antibody test for Bordetella pertussis, so all were treated with 5 days of azithromycin. Two of the infants were subsequently diagnosed with hypertrophic pyloric stenosis and underwent surgical pyloromyotomies 6 and 7 weeks, respectively, after the initial admission.

Criteria supporting the study of drugs in the newborn

BACKGROUND

Profound changes in the development and the maturation of neonates' organs and organ systems over variable periods of time potentially place neonates at increased risk and/or at different risks compared with adults or older children on exposure to pharmaceutical agents. Most studies of drugs in neonates focus on pharmacokinetic and pharmacodynamic end points and include insufficient numbers of patients to permit evaluation of safety. Only one fourth to one third of approved drugs have received adequate pediatric study to permit labeling for treatment of all appropriate pediatric populations.

OBJECTIVE

The initial goal of the Newborn Drug Prioritization Group was to develop a reproducible, objective process for evaluating drugs most in need of study in the neonatal population based on a universally acceptable priority ranking. The criteria would be applicable across therapeutic classes and would identify those drugs for which immediate study was most needed.

METHODS

Because the therapeutic requirements of the neonate are unique in comparison to older infants and children, the National Institute of Child Health and Human Development and the US Food and Drug Administration (FDA) developed the Newborn Drug Development Initiative to address the limited study of off-patent drugs in newborns. In March 2003, they convened a meeting of pediatric pharmacologists and pediatric specialists from the FDA, the American Academy of Pediatrics, the National Institutes of Health, and academic institutions to discuss how to increase the study of drugs for the newborn. One of the working groups was charged to develop generic criteria for overall prioritization of drugs for study in newborns. Because resources are limited, and not all drugs identified by the 4 clinically focused working groups can receive study at the same time, a process for priority ranking is necessary.

RESULTS

The panel identified 4 general categories containing different numbers of criteria as important for ranking drugs for priority investigation: (1) the disease and indication, including elements such as the potential for adverse outcomes, frequency in newborns, and level of evidence for treatment of newborns; (2) drug characteristics, including elements such as duration of dosing, lack of age-appropriate formulation, clinically relevant drug-drug and drug-disease interactions, and drug disposition in newborns; (3) feasibility and methodology for newborn studies, including both analytical considerations and clinical end points; and (4) the ethical basis for study, including elements to address benefit or harm due to exposure to the study drug, study methodology, and benefit of the new treatment relative to established standard therapy. Based on these categories, a list of criteria to warrant study of a drug in newborns was developed.

CONCLUSION

A process for judicious use of limited resources to rectify these deficiencies remains an urgent public health need.

Conservative treatment of infantile hypertrophic pyloric stenosis with intravenous atropine sulfate does not replace pyloromyotomy

Pyloromyotomy as described by Weber and Ramstedt has been the standard therapy for infantile hypertrophic pyloric stenosis since the 1960's and conservative therapy has been abandoned. The objective of this study was to test the effectiveness of systemic atropine applied intravenously for 7 days as a conservative therapeutic strategy and as an alternative to primary operation. Forty-two consecutive term infants with infantile hypertrophic pyloric stenosis were enrolled in the study over a period of 5 years. After confirmation of the diagnosis they all received intravenous atropine at a dose of 0.04 mg/(kg day) and increased by 0.01 mg/(kg day) up to 0.12 mg/(kg day), given as 6-8 single doses per/day. Nine pairs of parents requested that their child should be operated before completing the 7 days of medical therapy. Surgery was necessary in 8 of the remaining 33 infants (24,.2%) who did not improve after 7 days of conservative treatment. Successful treatment with i.v. atropine sulfate was achieved only in 25/33 term infants at an average maximal dose of 0.11 mg/(kg day), without any major side effects. Intravenous atropine sulfate has been considered as a potential alternative therapeutic strategy in the treatment of infantile hypertrophic pyloric stenosis. Clinical improvement however was often not seen before the 6th or 7th day of intravenous treatment. A success rate for the conservative approach of only 75% at day 7 in our study does not favour atropine therapy, in view of success rates above 95% with surgical repair.

Neonatal chlamydial infections: prevention and treatment

Neonatal chlamydial infection, which manifests principally as ophthalmia neonatorum (ON) or pneumonia, is a significant cause of neonatal morbidity. Widespread use of silver nitrate drops resulted in a dramatic decline in the incidence of gonococcal ophthalmia but had much less impact on the incidence of neonatal chlamydial infection. Chlamydia trachomatis has become the most common infectious cause of ON in developed countries.A number of prophylactic antibiotic or antiseptic agents have been used to prevent ON. Prophylaxis with 1% silver nitrate ophthalmic drops, 0.5% erythromycin ophthalmic ointment, or 1% tetracycline ointment has comparable efficacy for the prevention of chlamydial ophthalmia but does not offer protection against nasopharyngeal colonization or the development of pneumonia. Erythromycin or tetracycline topically have been used as prophylactic agents because of their allegedly superior activity for the prevention of ON and because they produced less chemical conjunctivitis compared with silver nitrate. However, the relative efficacy of these agents for chlamydial infection and the emergence of beta-lactamase-producing Neisseria gonorrheae has raised questions regarding their effectiveness when applied topically for prophylaxis of ON. Compared with these agents, a 2.5% povidone-iodine ophthalmic solution has been found to have greater efficacy for the prevention of ON generally, and chlamydial ophthalmia specifically. In countries where the incidence of ON is very low, an alternative strategy is to institute prenatal screening and treatment of infected mothers, forgo routine neonatal prophylaxis, and follow-up infants after birth for the possible development of infection. For the treatment of chlamydial ophthalmia or pneumonia, oral erythromycin for 2 weeks is recommended; additional topical therapy is unnecessary. However, in approximately 20-30% of infants, therapy will not eradicate the organism and the infant may require a repeat oral course of antibiotics. The few published studies on the use of the new oral macrolide antibiotics, such as azithromycin, roxithromycin, or clarithromycin for chlamydial infections in neonates suggest that these agents may be effective; however, more data on their tolerability and efficacy in this patient group are warranted.

Critical appraisal of the role of Ureaplasma in the development of bronchopulmonary dysplasia with metaanalytic techniques

BACKGROUND

Controversy exists over whether or not Ureaplasma colonization or infection of the respiratory tract contributes to the development of bronchopulmonary dysplasia (BPD). Because BPD is a major cause of morbidity and mortality in preterm infants and a potential therapeutic intervention with antimicrobials is possible, we sought to evaluate and critique the current medical literature and to document the reported association between Ureaplasma and BPD.

METHODS

We analyzed all peer-reviewed articles and previous reviews including cross-references that reported Ureaplasma respiratory tract colonization or infection and development of BPD in neonates published from January 1966 to December 2004. Inclusion criteria included a cohort limited to all neonatal intensive care unit admissions or all colonized infants, articles that did not define a numerator and a denominator for BPD and Ureaplasma or that included patients from other reports were excluded from the analysis. We evaluated BPD at 28 postnatal days (BPD28) or 36 weeks post-menstrual age (BPD36).

RESULTS

Twenty-three studies with an aggregate of 2216 infants reported BPD28, and 8 studies with 751 infants reported BPD36. Although there was significant association between Ureaplasma colonization and both BPD28 and BPD36, there was substantial heterogeneity (Q test statistic, P < 0.01). We therefore focused on describing the study characteristics associated with an increased relative proportion of BPD. The greatest contribution to effect was from the studies enrolling fewer than 100 infants.

CONCLUSION

Ureaplasma colonization is associated with higher reported rates of BPD, but the greatest reported effect is seen in small studies; reporting bias may be partially responsible for this effect.

The diagnosis and management of gastro-oesophageal reflux in infants

Gastro-oesophageal reflux (GOR) and gastro-oesophageal reflux disease (GORD) occur frequently during the first months of life. Gastro-oesophageal reflux may be a primary gastro-intestinal motility disorder, but it may also be secondary to other conditions such as cow's milk protein allergy. Objective diagnosis can be difficult because there may be absence of correlation between history, results of pH monitoring and histology. Severe GORD may cause minor symptoms, and minor GOR may cause severe symptoms. Several different therapeutic interventions exist. Simply stated, thickened formula reduces regurgitation and alginates and proton pump inhibitors can be used to decrease acid GOR, depending on the severity of the GORD. Efficacy data of prokinetic drugs are either lacking or disappointing. Regarding side-effects, interest has been focused on cisapride, although other molecules have similar effects. Long-term side-effects such as the nutritional consequence of therapeutic management have been insufficiently studied, especially for the acid-reducing molecules.

Erythromycin as a prokinetic agent in preterm neonates: a systematic review

BACKGROUND

It often takes several days or even weeks to establish full enteral feeds (FEFs) in preterm, especially extremely low birthweight neonates because of feed intolerance related to gastrointestinal hypomotility. Clinical trials of erythromycin as a prokinetic agent in preterm neonates have reported conflicting results.

AIM

To systematically review the efficacy and safety of erythromycin as a prokinetic agent in preterm neonates.

METHODS

Only randomised controlled trials in preterm neonates (gestation < or = 37 weeks) were considered eligible for inclusion. The primary outcome was the time to reach FEFs of 150 ml/kg/day. The secondary outcomes included the incidence of erythromycin related adverse effects such as diarrhoea, cardiac arrhythmias, and hypertrophic pyloric stenosis. No restrictions were applied on the dose (low: 3-12 mg/kg/day; antimicrobial: > or = 12 mg/kg/6-8 hours) and route (oral or intravenous) and mode (prophylactic or rescue) of administration. The standard methodology for systematic reviews was followed. A subgroup analysis was pre-planned based on the dose and mode of drug administration.

RESULTS

Seven trials (three prophylaxis, four rescue) with various doses, routes and modes of administration, and durations of erythromycin treatment and different results were found to be eligible for inclusion in the analysis. Meta-analysis could not be performed, as specific data were either inadequate or not available.

CONCLUSION

The conflicting trial results may be explained by differences in dose and route and mode of administration of erythromycin and in gastrointestinal motor responses in the presence of different feeding conditions-for example, fasting v fed state, intermittent v continuous feeds. Gestational and postnatal ages during erythromycin treatment are also important.

Use of antibiotics in the prevention and treatment of pertussis

Antibiotics are commonly used for treating confirmed cases of pertussis and also for disease prevention in outbreak situations, and there is little evidence of antibiotic resistance of Bordetella pertussis. The most commonly used antibiotic is erythromycin, but the associated side effects limit compliance and therefore efficacy. Other antibiotics, such as clarithromycin and azithromycin, have been shown to be at least as effective as erythromycin in preventing and treating pertussis, and they also have fewer side effects, which improves compliance. This article outlines the use of different antibiotics in pertussis management and their effect on preventing disease transmission and reducing disease severity and duration.

Safety and tolerability of azithromycin in pediatric infectious diseases: 2003 update

Oral azithromycin suspension has been prescribed to >80 million patients. Children find the color and taste of the oral suspension of azithromycin agreeable, and the drug is well-tolerated. On average 9% of patients have treatment-related adverse events, which are most frequently gastrointestinal complaints. The side effects are mild to moderate and very seldom necessitate withdrawal of the treatment. In addition to the conventional 3-day 10-mg/kg/day regimen and the 10 mg/kg on Day 1 followed by 5 mg/kg on Days 2 to 5 regimens, single dose 30 mg/kg and 3-day 20-mg/kg/day regimens are well-tolerated, although these new dosages are associated with more adverse effects.