Neonatal apnea and gastroesophageal reflux (GER): is there a problem?

Effects of Nasal Respiratory Support on Laryngeal and Esophageal Reflexes in Preterm Lambs

BACKGROUND

Significant cardiorespiratory events can be triggered in preterm infants as part of laryngeal chemoreflexes (LCRs) and esophageal reflexes (ERs). We previously showed that nasal continuous positive airway pressure (nCPAP) blunted the cardiorespiratory inhibition induced with LCRs. Therefore, we aimed to compare the effects of nCPAP and high-flow nasal cannulas (HFNC) on the cardiorespiratory events induced during LCRs and ERs. The hypothesis is that nCPAP but not HFNC decreases the cardiorespiratory inhibition observed during LCRs and ERs.

METHODS

Eleven preterm lambs were instrumented to record respiration, ECG, oxygenation, and states of alertness. LCRs and ERs were induced during non-rapid eye movement sleep in a random order under these conditions: nCPAP 6 cmH2O, HFNC 7 L/min, high-flow nasal cannulas 7 L/min at a tracheal pressure of 6 cmH2O, and no respiratory support.

RESULTS

nCPAP 6 cmH2O decreased the cardiorespiratory inhibition induced with LCRs, but not with ERs in preterm lambs. This blunting effect was less marked with HFNC 7 L/min, even when the tracheal pressure was maintained at 6 cmH2O.

CONCLUSIONS

nCPAP might be a treatment for cardiorespiratory events related to LCRs in newborns, either in the context of laryngopharyngeal refluxes or swallowing immaturity. Our preclinical results merit to be confirmed through clinical studies.

IMPACT

Laryngeal chemoreflexes can be responsible for significant cardiorespiratory inhibition in newborns, especially preterm. Nasal continuous positive airway pressure at 6 cmH2O significantly decreased this cardiorespiratory inhibition. High-flow nasal cannulas at 7 L/min had a lesser effect than nasal continuous positive airway pressure. Esophageal stimulation was responsible for a smaller cardiorespiratory inhibition, which was not significantly modified by nasal continuous positive airway pressure or high-flow nasal cannulas. Nasal continuous positive airway pressure should be tested for its beneficial effect on cardiorespiratory events related to laryngeal chemoreflexes in preterm newborns.

Antacids revisited: review on contemporary facts and relevance for self-management

Heartburn and acid regurgitation are the typical symptoms of gastroesophageal reflux. Despite the availability of several treatment options, antacids remain the mainstay treatment for gastroesophageal reflux-related symptoms based on their efficacy, safety, and over-the-counter availability. Antacids are generally recommended for adults and children at least 12 years old, and the FDA recommends antacids as the first-line treatment for heartburn in pregnancy. This narrative review summarizes the mechanism, features, and limitations related to different antacid ingredients and techniques available to study the acid neutralization and buffering capacity of antacid formulations. Using supporting clinical evidence for different antacid ingredients, it also discusses the importance of antacids as OTC medicines and first-line therapies for heartburn, particularly in the era of the COVID-19 pandemic, in which reliance on self-care has increased. The review will also assist pharmacists and other healthcare professionals in helping individuals with heartburn to make informed self-care decisions and educating them to ensure that antacids are used in an optimal, safe, and effective manner.

Are we over-treating hypoxic spells in preterm infants?

A frequent challenge in Neonatology is the high frequency of spontaneously occurring hypoxemic events, a majority of which are associated with apnea or hypoventilation. These episodes present a challenge for caregivers and families as they frequently delay discharge of preterm infants. Supplemental oxygen, respiratory support, and caffeine therapy are widely used as therapeutic approaches, but challenges remain regarding their precise indications. Future clinical practice should be directed by an evidence-based approach including automated supplemental oxygen, minimizing the use of medications for gastroesophageal reflux, optimal timing and dosage of caffeine therapy, and standardization of alarm limits and discharge monitoring protocols.

Decreasing Inappropriate Use of Antireflux Medications by Standardizing Gastroesophageal Reflux Disease Management in NICU

Gastroesophageal reflux (GER) is a functional self-limiting condition in neonates. When pathologic, it is called GER disease (GERD). There are wide variations in the management of signs, symptoms, and complications associated with GERD in the neonatal intensive care unit (NICU). Evidence does not support an empiric trial of GERD medications as a diagnostic tool or therapy in premature infants.

Methods

A multidisciplinary team developed evidence-based clinical practice guidelines (CPG) for GERD management. Process improvement included developing a GERD management algorithm, electronic order sets, and education for all providers. Multiple plan-do-study-act cycles done.

Results

Implementation of standardized GERD management guideline, decreased the overall use of antireflux medications from baseline, 15.1%-6.8% [χ² (1, N = 1259) = 12.98, P < 0.001]. There was elimination of GERD medication use in preterm from baseline of 19.3% [χ² (1, N = 220) = 12.18, P < 0.001]. The most frequently used GERD medication was lansoprazole, with an incorrect initial dosing rate of 55.0% that deceased to zero [χ² (1, N = 33) = 10.73, P = 0.001]. Appropriate testing with PH probe with 24-hour multichannel impedance was observed (17.1%-28.0%) identifying patients with correct GERD diagnosis [χ² (1, N = 101) = 1.41, P = 0.236]. Length of stay for GERD patient's improved from a median of 89-53 days.

Conclusion

Standardizing clinical management leads to best practices for GERD management with appropriate diagnostic testing, eliminating incorrect medication dosing, and improved patient safety with value-based outcomes.

Reducing Antacid Use in a Level IV NICU: A QI Project to Reduce Morbidity

Introduction

Gastroesophageal reflux is a physiologic occurrence in infants. Clinicians caring for neonates use histamine-2 receptor antagonists (H2As) or proton pump inhibitors (PPIs) for symptomatic reflux, apnea/bradycardia/desaturations, or irritability. Recent studies have shown that there is an increased incidence of infection, fracture, and mortality in neonates who receive antacids.

Methods

A multidisciplinary team aimed to decrease nonindicated antacid use in the NICU by 50% by April 2019. Outcome measures include the median number of inappropriate antacid prescriptions and patient-days on acid-suppressants. Interventions include education regarding use and risks of antacids, development of a list of indications deemed "appropriate" for starting an H2A or PPI, mandatory discussion on rounds when considering antacids, documentation of treatment goal, and indication, and an automatic drop-off in the electronic medical record.

Results

Baseline data (June-December 2017) showed 19 prescriptions of H2As or PPIs. Of those, 10 orders were deemed "inappropriate," according to our indicated uses. There were 407 total patient-days of medication-use (median: 51 patient-days). After the implementation of the interventions (October 2018-May 2019), there were 11 prescriptions of antacid medications, 3 of which were deemed "inappropriate." There were 206 total days of medication-use (median: 18.5 patient-days).

Conclusions

A multidisciplinary agreement on indications for antacid use in neonates stimulates discussion and creates more purposeful use. Overall, we successfully decreased nonindicated antacid prescriptions in the NICU. For the next steps, we hope to educate physicians on the risks of antacid use and reduce prescriptions in other areas of the hospital and the outpatient setting.

Apnea in preterm neonates: what's the role of gastroesophageal reflux? A systematic review

A causal relationship between gastro-esophageal reflux (GER) and apnea in preterm infants has been frequently hypothesized and is currently debated. The present study aims at reviewing the currently available scientific evidence, in order to clarify the role of GER on the occurrence of apnea and to help improving the clinical management of apneic preterm neonates. We performed a systematic literature search to identify all the clinical studies on preterm neonates that properly assessed the relationship between apnea and GER. Two-hundred and fifty-two papers, including 32 reviews and meta-analysis, were screened. Out of them, only 7 were included in the final analysis according to the selected criteria. Among them, 3 studies reported an increased frequency of apnea after reflux compared to reflux-free period and 4 denied a significant temporal relation. In conclusion, a minority of apneic events occurs soon after GER episodes. Whether this happens by chance or because of a causal relationship is still impossible to define. Based on the available data, empirical treatment with acid inhibitors is not recommended in neonates with apnea unless a proven temporal relation is shown by simultaneous esophageal pH-impedance and polysomnography or cardiorespiratory monitoring and in the absence of a clear clinical benefit.

Etiologies of apnea of infancy

BACKGROUND

To date there are limited data in the literature to guide the initial evaluation for etiologies of apnea in full-term infants born at greater than or equal to 37 weeks conceptional age (apnea of infancy [AOI]). Pediatricians and pediatric pulmonologists are left to pursue a broad, rather than targeted and a stepwise approach to begin diagnostic evaluation.

METHODS

We performed a retrospective chart review of 101 symptomatic full-term infants (age under 12 months) diagnosed with apnea with an inpatient multichannel pneumogram (six channels) or a fully attended overnight pediatric polysomnogram in our outpatient sleep center accredited by American Academy of Sleep Medicine (AASM), scored using the standards set forth by the AASM. The infant was diagnosed as having AOI if the apnea hypopnea index (AHI) was greater than 1 (AHI is defined as the number of apnea and hypopnea events per hour of sleep). The final diagnosis/etiology was determined based on physician clinical assessment and work up. We then determined the frequency for each diagnosis.

RESULTS

We found that the three most common etiologies were gastroesophageal reflux disease (GERD) (48/101), upper airway abnormalities/obstruction (37/101), and neurological diseases (19/101). There were significant numbers of infants with multiple etiologies for AOI.

CONCLUSION

Based on the frequencies obtained, pediatric practitioners caring for full-term infants with apnea of unknown etiology are advised to begin with evaluation of more likely causes such as GERD and upper airway abnormalities/obstruction before evaluating for less common causes.

Gastroesophageal Reflux Poses a Potential Risk for Late Complications of Bronchopulmonary Dysplasia: A Prospective Cohort Study

BACKGROUND

Bronchopulmonary dysplasia (BPD) is the most common respiratory disorder in extremely low birth weight infants. Although most symptoms of BPD improve, some late complications exist, even with regular treatment. Gastroesophageal reflux (GER), also common in extremely premature infants, may be related to many cardiorespiratory symptoms. However, the potential of GER as a risk factor for late complications associated with BPD is still unclear.

RESEARCH QUESTION

The goal of this study was to determine if GER increases the risk of late complications of BPD in infants.

STUDY DESIGN AND METHODS

A multicenter prospective cohort of 131 infants (79 male subjects, 52 female subjects) with BPD was enrolled. The development of late complications was assessed over an 18-month follow-up period. Twenty-four-hour pH-multichannel intraluminal impedance and gastric sodium concentrations were analyzed in all infants at 36 weeks' postmenstrual age and at the last interview. Prevalence and risk factors of late complications of BPD were analyzed by using forward logistic regression.

RESULTS

The prevalence of late complications in BPD infants was 63.79% and included respiratory symptoms (49.14%), vomiting (38.79%), retinopathy of prematurity (25.86%), hypoxic-ischemic injury (3.45%), rehospitalization (26.72%), and sudden death (0.86%). Respiratory diseases constituted the most frequent complication. The prevalence of GER in BPD was 42.24% and included acid GER (18.10%) and duodenogastroesophageal reflux (DGER; 24.14%). Risk factors for respiratory symptoms were gestational age ≤ 30 weeks (OR, 3.213; 95% CI, 1.221-8.460), birth weight < 1,500 g (OR, 2.803; 95% CI, 1.014-7.749), invasive ventilation > 7 days (OR, 4.952; 95% CI, 1.508-16.267), acid GER (OR, 4.630; 95% CI, 1.305-16.420), and DGER (OR, 5.588; 95% CI, 1.770-17.648). Infants with BPD and DGER were more prone to late complications than those with acid GER or no reflux.

INTERPRETATION

The prevalence of late complications is high in infants with BPD. GER (and in particular, DGER) poses a tentative risk for these late complications.

TRIAL REGISTRY

ClinicalTrials.gov; No.: NCT03014453; URL: www.clinicaltrials.gov.

Gastroesophageal reflux in children: an updated review

Background

Gastroesophageal reflux is a common disorder in pediatrics. Clinicians should be familiar with the proper evaluation and management of this condition.

Objective

To provide an update on the current understanding, evaluation, and management of gastroesophageal reflux in children.

Methods

A PubMed search was performed with Clinical Queries using the key term ‘gastroesophageal reflux’. The search strategy included meta-analyses, randomized controlled trials, clinical trials, observational studies, and reviews. The search was restricted to the English literature and the pediatric age group.

Results

Regurgitation is the most frequent symptom of gastroesophageal reflux and is present in nearly all cases. Gastroesophageal reflux occurs normally in infants, is often physiological, peaks at 4 months of age, and tends to resolve with time. Gastroesophageal reflux disease occurs when gastric contents reflux into the esophagus or oropharynx and produce troublesome symptom(s) and/or complication(s). A thorough clinical history and a thorough physical examination are usually adequate for diagnosis. When the diagnosis is ambiguous, diagnostic studies may be warranted. A combined esophageal pH monitoring and multichannel intraluminal esophageal electrical impedance device is the gold standard for the diagnosis of gastroesophageal reflux disease if the diagnosis is in doubt. In the majority of cases, no treatment is necessary for gastroesophageal reflux apart from reassurance of the benign nature of the condition. Treatment options for gastroesophageal reflux disease are discussed.

Conclusion

In most cases, no treatment is necessary for gastroesophageal reflux apart from reassurance because the condition is benign and self-limiting. Thickened feedings, postural therapy, and lifestyle changes should be considered if the regurgitation is frequent and problematic. Pharmacotherapy should be considered in the treatment of more severe gastroesophageal reflux disease for patients who do not respond to conservative measures. Proton pump inhibitors are favored over H₂-receptor antagonists because of their superior efficacy. Antireflux surgery is indicated for patients with significant gastroesophageal reflux disease who are resistant to medical therapy.

A pilot study of limb stimulation for the treatment of neonatal apnea

This study explored the feasibility effect and safety of the limb stimulation (LS) for the treatment of neonatal apnea (NAP).The cases of 30 eligible premature infants with NAP were included in this retrospective study. These cases were equally divided into an intervention group (n = 15) and a control group (n = 15). The infants in both groups received caffeine treatment. Moreover, cases in the intervention group also received LS for a total 30 hours, while the subjects in the control group did not receive LS during this period. The primary outcome included apnea frequency (number of episodes per 24 hours), and apnea rate. The secondary outcomes consisted of desaturation (number of episodes per 24 hours), and heart rate (beats per minute). Additionally, adverse events were also documented during the treatment period.After treatment, LS did not show better outcomes in apnea frequency (P = .48), apnea rate (P = .33), desaturation (P = .55), and heart rate (P = .41). Furthermore, no significant differences of all adverse events were found between 2 groups.The results of this pilot study demonstrated that LS might be not efficacious for premature infants with NAP.

Cardiorespiratory events in infants with gastroesophageal reflux symptoms: Is there any association?

BACKGROUND

Cardiorespiratory (CR) events (apnea, bradycardia, oxygen desaturation) and gastroesophageal reflux (GER) symptoms often coexist in infants admitted to Neonatal Intensive Care Unit, leading to over-prescription of drugs and delayed discharge. We aimed to evaluate the relationships between CR and GER events.

METHODS

The temporal associations between CR and GER events were analyzed in symptomatic infants who underwent synchronized CR and pH-impedance monitoring. The symptom association probability (SAP) index was used to identify infants with a significant number of temporal associations. Gastroesophageal reflux characteristics and the chronological sequence of CR and GER events occurring within 30 seconds of each other were evaluated according to SAP index.

KEY RESULTS

Of the 66 infants enrolled, aged 29 (18-45) days, 58 had CR events during monitoring. From these 58 patients, a total of 1331 CR events and 5239 GER (24% acidic) were detected. The SAP index was positive in seven (12%) infants. These infants had greater GER frequency, duration, and proximal extent (P < .05). The number of temporal associations was 10 times greater in the positive SAP group. Gastroesophageal reflux events preceded CR events in 83% of these associations. These GER events had a higher proximal extent (P = .004), but showed no differences in pH values.

CONCLUSIONS & INFERENCES

The simultaneous evaluation of CR and GER events could be useful to identify infants with severe GER and significant temporal associations between these events. Treatment of GER could be indicated in these infants, but as the GER events involved are mainly non-acidic, empirical treatment with antacids is, often, inappropriate.

Progression of Gastric Acid Production in Preterm Neonates: Utilization of In-vitro Method

Background: Limited studies are done regarding ability to produce gastric acid in preterm infants and most studies used in vivo method of assessing gastric pH. Objectives: To assess the feasibility of using an in vitro method of measuring gastric pH in babies ≤ 28 weeks gestational age (GA) and determine whether changes in gastric pH differ with gestational age, mode of delivery, and use of antenatal steroids. Design/Methods: Prospective study that enrolled extremely low birth weight (ELBW) babies. Gastric aspirate collected before feeding. In vitro testing of gastric aspirates for pH were done on days of life 1, 3, 5, 7, 14, and 28 by using pH electrode. The pH was measured on each sample in triplicate, mean calculated and used for data analysis. Stastical methods included descriptive statistics, t-tests and repeated measures ANOVA. Results: 29 subjects ≤ 28 weeks or birth weight ≤ 1,000 g were enrolled. No significant change was noted in pH measurements over time. Antenatal steroids and mode of delivery did not affect gastric acid pH. Conclusion: The in vitro method for gastric pH measurements is non-invasive and affords more frequent testing. It would be useful in studying various conditions that may affect gastric pH.

Apnea, bradycardia and desaturation spells in premature infants: impact of a protocol for the duration of 'spell-free' observation on interprovider variability and readmission rates

OBJECTIVE

To study the impact of implementing a protocol to standardize the duration of observation in preterm infants with apnea/bradycardia/desaturation spells before hospital discharge on length of stay (LOS) and readmission rates.

STUDY DESIGN

A protocol to standardize the duration of in-hospital observation for preterm infants with apnea, bradycardia and desaturation spells who were otherwise ready for discharge was implemented in December 2013. We evaluated the impact of this protocol on the LOS and readmission rates of very low birth weight infants (VLBW). Data on readmission for apnea and an apparent life-threatening event (ALTE) within 30 days of discharge were collected. The pre-implementation epoch (2011 to 2013) was compared to the post-implementation period (2014 to 2016).

RESULTS

There were 426 and 368 VLBW discharges before and after initiation of the protocol during 2011 to 2013 and 2014 to 2016, respectively. The LOS did not change with protocol implementation (66±42 vs 64±42 days before and after implementation of the protocol, respectively). Interprovider variability on the duration of observation for apneic spells (F-8.8, P=0.04) and bradycardia spells (F-17.4, P<0.001) decreased after implementation of the protocol. The readmission rate for apnea/ALTE after the protocol decreased from 12.1 to 3.4% (P=0.01).

CONCLUSION

Implementing an institutional protocol for VLBW infants to determine the duration of apnea/bradycardia/ desaturation spell-free observation period as recommended by the American Academy of Pediatrics clinical report did not prolong the LOS but effectively reduced interprovider variability and readmission rates.

Reflex cardiorespiratory events from esophageal origin are heightened by preterm birth

The involvement of gastroesophageal refluxes in cardiorespiratory events of preterm infants remains controversial. While a few studies in full-term newborn animals have shown that stimulation of esophageal receptors leads to cardiorespiratory reflexes, the latter remain largely unknown, especially after premature birth. The present study aimed to 1) characterize the cardiorespiratory reflexes originating from esophageal receptors in newborn lambs and 2) test the hypotheses that preterm birth enhances reflex cardiorespiratory inhibition and that C-fibers are involved in these reflexes. Eight full-term lambs and 10 lambs born 14 days prematurely were studied. Following surgical instrumentation, a 6-h polysomnography was performed without sedation to record electrocardiogram, respiratory movements, arterial pressure, laryngeal constrictor muscle activity, state of alertness, and hemoglobin oxygen saturation. Five esophageal stimulations of the upper and/or lower esophagus, including rapid balloon inflation and/or HCl injection, were performed in random order. A second recording was performed in full-term lambs 24 h later, after C-fiber blockade by capsaicin. Results confirmed that esophageal stimulations induced inhibitory cardiorespiratory reflexes combined with protective mechanisms, including laryngeal closure, swallowing, coughing, increased arterial pressure, and arousal. Preterm birth heightened cardiorespiratory inhibition. The strongest cardiorespiratory inhibition was observed following simultaneous stimulation of the lower and upper esophagus. Finally, cardiorespiratory inhibition was decreased after C-fiber blockade. In conclusion, esophageal stimulation induces inhibitory cardiorespiratory reflexes, which are partly mediated by C-fibers and more pronounced in preterm lambs. Clinical relevance of these findings requires further studies, especially in conditions associated with increased cardiorespiratory events, e.g., neonatal infection.NEW & NOTEWORTHY Preterm birth heightens the cardiorespiratory events triggered by esophageal stimulation. The most extensive cardiorespiratory events are induced by simultaneous stimulation of the proximal and distal esophagus.

Acid Gastroesophageal Reflux Disease and Apparent Life-Threatening Events: Simultaneous pH-metry and Cardiorespiratory Monitoring

AIM

To investigate the prevalence and the characteristics of gastroesophageal reflux disease (GERD) in infants with apparent life threatening events (ALTE).

MATERIALS AND METHODS

Infants with at least one episode of ALTE in absence of predisposing factors were included. All infants underwent a cardiorespiratory recording with simultaneous 24-hour pH-monitoring. Patients were divided into 3 groups according to the severity of GERD: A. Reflux Index (RI) <3%, B. RI = 3-7%, C. RI >7%. Monthly evaluations were performed and the anti-reflux therapy was maintained till normalization of monitoring and clinic.

RESULTS

41 infants were enrolled. GERD was found in 80% of patients (moderate in 54%, severe in 27%). A normalization of the cardiorespiratory tracks was recorded on average after 1 month for group A, 7 months for the group B and 9.5 months for group C. A significant difference was registered between group A and both group B and C (P < 0.0001), as well as between the group B and C (P < 0.05).

CONCLUSION

GERD influences significantly the time of normalization of the cardiorespiratory monitoring in infants with ALTE. GERD diagnosis and treatment are mandatory in these patients.

Widespread use of gastric acid inhibitors in infants: Are they needed? Are they safe?

Gastroesophageal reflux is a common phenomenon in infants, but the differentiation between gastroesophageal reflux and gastroesophageal reflux disease can be difficult. Symptoms are non-specific and there is increasing evidence that the majority of symptoms may not be acid-related. Despite this, gastric acid inhibitors such as proton pump inhibitors are widely and increasingly used, often without objective evidence or investigations to guide treatment. Several studies have shown that these medications are ineffective at treating symptoms associated with reflux in the absence of endoscopically proven oesophagitis. With a lack of evidence for efficacy, attention is now being turned to the potential risks of gastric acid suppression. Previously assumed safety of these medications is being challenged with evidence of potential side effects including GI and respiratory infections, bacterial overgrowth, adverse bone health, food allergy and drug interactions.

Diagnostic Evaluation and Home Monitor Use in Late Preterm to Term Infants With Apnea, Bradycardia, and Desaturations

Apnea, bradycardia, and oxygen desaturation events are a common in neonatal intensive care units, with relevant literature to date largely focusing on very low birth weight and extremely low birth weight infants. We conducted a retrospective review of infants born at ≥34 weeks gestational age at 2 tertiary neonatal intensive care units in Boston, MA, between January 2009 and December 2013. Our objectives included (1) describing the diagnostic evaluations performed in late preterm to term infants with discharge-delaying apnea, bradycardia, or oxygen desaturation events and (2) identifying variables associated with home monitor use. Of the 741 eligible infants identified, diagnostic evaluations were variable and infrequent with blood culture, blood glucose, and head ultrasound performed most commonly. The likelihood of home monitor use was greater in infants with either a prolonged inpatient stay or greater gestational age at birth.

Treatment options for apnoea of prematurity

Apnoea of prematurity (AOP) affects almost all infants born at <28 weeks gestation or with birth weight <1000 g. When untreated, AOP may be associated with negative outcomes. Because of these negative outcomes, effective treatment for AOP is an important part of optimising care of preterm infants. Standard treatment usually involves xanthine therapy and respiratory support. Cutting-edge work with stochastic vibrotactile stimulation and new pharmaceutical agents continues to expand therapeutic options. In this article, we review the pathophysiology of AOP, associated conditions and treatment options.

HOXA genes cluster: clinical implications of the smallest deletion

Background

HOXA genes cluster plays a fundamental role in embryologic development. Deletion of the entire cluster is known to cause a clinically recognizable syndrome with mild developmental delay, characteristic facies, small feet with unusually short and big halluces, abnormal thumbs, and urogenital malformations. The clinical manifestations may vary with different ranges of deletions of HOXA cluster and flanking regions.

Case presentation

We report a girl with the smallest deletion reported to date involving the entire HOXA cluster at 7p15.2-p14.3. The patient was the third child born to a healthy and non-consanguineous Italian couple. She was born at the 34th week of gestation by caesarean section due to cholestasis of pregnancy. Her birth weight, length, and occipitofrontal circumference were 2,140 g (25-50th centile), 46 cm (50th centile), and 33 cm (75-90th centile), respectively. The Apgar scores were 8 at both the 1st and 5th minutes. The patient presented with typical mild facial anomalies, hand and feet abnormalities, urinary anomalies, and mild speech delay. Unexpectedly, the patient demonstrated complex unusual features of multiple episodes of oxyhemoglobin desaturation, laryngeal stridor and a branchial cyst. Chromosome analysis of the patient revealed an apparently normal karyotype at the 550 band level. Based on array comparative genomic hybridization, a 2.5 Mb interstitial deletion was detected at 7p15.2p14.3 (chr7: 26,333,553-28,859,312), involving the entire HOXA cluster and a small number of other genes as SNX10, SKAP2, EVX1, HIBADH, TAX1BP1, JAZF1, and CREB5.

Conclusions

This report improves our understanding of the genotype-phenotype correlations of HOXA genes cluster deletions via the identification and characterization of the smallest deletion (as well as critical region) reported to date. In particular we discuss the possible implications of preterm and haploinsufficiency in the pathogenesis of the unusual findings, furthermore opening new discussion and interpretation cues.

Can MII-pH values predict the duration of treatment for GERD in preterm infants?

BACKGROUND

Little is known regarding the prognostic role of Multichannel Intraluminal Impedance and pH monitoring (MII/pH) parameters in preterm infants with Gastro-Esophageal Reflux Disease (GERD).

AIM

Our study aimed to evaluate the relationship between MII/pH variables and the duration of pharmacological therapy for GERD, in preterm infants with gestational age (GA) ≤34weeks.

SUBJECTS, STUDY DESIGN, OUTCOME MEASURES

We retrospectively reviewed data of all newborns with GA ≤34weeks that underwent MII/pH in our Neonatal Intensive Care Unit (NICU) and pharmacological treatment for GERD. We included them in a 12-month follow-up program. MII/pH parameters were used as independent variables and the duration of pharmacological therapy as dependent variable in linear regression models.

RESULTS

16 patients (GA 28.4±1.8weeks, BW 1122±427g) were enrolled into the study. Regression analysis performed on all reflux events reported a significant correlation between the duration of pharmacological treatment and MII-BEI (r(2)=0.36, p=0.01) and MII-reflux frequency (r(2)=0.33, p=0.02). Moreover, regression analysis performed on all events classified according to the corresponding pH change - acidic (ac.), weakly acidic (w.ac.) or weakly alkaline (w.a.) - showed a significant correlation between the duration of pharmacological treatment and MII-w.ac.BEI (r(2)=0.26, p=0.05), MII-w.ac. reflux frequency (r(2)=0.44, p=0.01), and MII-proximal w.ac. reflux frequency (r(2)=0.35, p=0.02). No statistically significant correlation was found between pH-Reflux Index and the duration of treatment.

CONCLUSION

The study shows how, in our population of preterm infants, MII-parameters could have not only a diagnostic role, but also a prognostic value in terms of the duration of pharmacological treatment.