Gastroesophageal Reflux Disease (GERD) and Allergies

Gastroesophageal reflux (GER) is defined as the retrograde movement of gastric contents into the oesophagus; it is a physiologic process that occurs in everyone, young and old, particularly after meals. GER often mimics food allergy in infancy (usually cow’s milk), but occasionally it can be caused by food allergy.

Classification of GER:

The most useful classification of GER divides the spectrum of reflux into 3 caterories:

  • Functional GER represents a benign condition that does not require evaluation or treatment. This does not cause inflammation and does not lead to any long term complication. This category ranges from passage of refluxate into the lower oesophagus to frequent regurgitation of gastric contents out of the mouth typically seen in infants.
  • GERD, in contrast, requires treatment. This class represents GER with associated complications, either typical in infants ( e.g., failure to thrive, anaemia, oesophagitis, Barrett’s oesophagus) or atypical (e.g., wheezing, apnea, pneumonia, chronic sinusitis).
  • Secondary GER is caused by some underlying condition, which causes retrograde movement of gastric contents. The appropriate treatment usually involves addressing the underlying cause directly (e.g., pyloric stenosis), or to obtain control of GER (e.g., neurologic impairment). Other conditions associated with secondary GER include food allergy, infection and nasogastric tubes, and metabolic defects.

GER in neurologically abnormal children

Children with neurological disability often suffer from feeding difficulties, vomiting, failure to thrive, recurrent chest infections and irritability, and such symptoms are often acceptesd as part of the disability. Abrahams and Burkitt in 1970 first reported the association of GER and cerebral palsy. They found reflux in 75% of cases of cerebral palsy.

Prevalence of GER depends on age. Approximately 50% of 0 — 3 month olds have at least 1 episode of regurgitation per day. This increases to a peak of 67% of infants at 4 months of age. The prevalence drops to approximately 5% of 10 — 12 month olds. The sharpest drop occurs around 6 months of age and is associated with the development of improved neuromuscular control and the infant sitting up. GER and reflux associated complications are more common in neurologically impaired children and premature infants.

Prognosis of GER in Infants:

GER spontaneously resolves in 81% of infants by age 18 months.

Causes and risk factors for GERD

GERD is caused by a weak oesophageal sphincter that is present at birth or that develops later in life. A hiatal hernia can also cause GERD. Hiatal Hernia is a condition in which the stomach pushes up into the diaphragm muscle. When this happens, the oesophageal sphincter does not work properly. As a result, the fluid can easily leak back into the oesophagus.

Factors that make GERD worse include:

  • Being overweight or obese
  • Being pregnant
  • Drinking alcohol or caffeine
  • Drinking carbonated beverages or fruit juice
  • Eating chocolate or peppermint
  • Eating fatty or spicy foods
  • Eating large meals
  • Lying down or bending over after a meal
  • Medications, such as aspirin and other anti-inflammatory medications
  • Smoking or using tobacco products

Symptoms of GERD in adults

Oesophageal symptoms:

  • The most common symptom of GERD is heartburn. It is perceived as a substernal burning sensation, and usually occurs after meals or when reclining at bedtime.
  • Regurgitation is a bitter or acidic taste in the mouth caused by gastric contents refluxed up into the oesophagus. Regurgitation is differentiated from vomiting by the lack of abdominal wall and gastrointestinal contraction.
  • Besides the discomfort of heartburn, reflux results in symptoms of oesophageal inflammation, such as odynophagia (pain on swallowing) and dysphagia (difficult swallowing).
  • Chest pain caused by reflux may be sharp or dull and may radiate widely into the neck, arms, or back. The pain is thought to be caused by either the stimulation of chemoreceptors, or by the distention of the esophagus, but may be caused by cardiac (microvascular angina) chest pain precipitated by reflux. It can be difficult to differentiate cardiac chest pain from reflux.

Extra-oesophageal symptoms:

  • Pulmonary
    The acid reflux may also cause pulmonary symptoms such as coughing ( 3rd commonest cause of chronic cough after PND and asthma), wheezing, asthma. Most studies show that 45% to 65% of adult asthmatics have GERD. Pulmonary symptoms may be caused directly by the aspiration of acid in the bronchial tree, but may also be caused indirectly by the acidification of the oesophagus, which causes vagally induced bronchoconstriction.
    Aspiration pnuemonia, and interstitial fibrosis can also be caused by GERD.
  • Oral symptoms such as tooth decay, gingivitis, halitosis (bad breath), and waterbrash (the spontaneous appearance of high volumes of saliva in the mouth, and is caused by vagally mediated reflex initiated by acid in the oesophagus)
  • Throat symptoms such as soreness, laryngitis and hoarseness are also symptoms of GERD.
  • Earache may result from acid damage to the oropharynx.

Investigations for GER

Lower oesophageal pH monitoring

Extended oesophageal pH monitoring over 18 — 24 hours is now well established as the ‘gold standard’ for documenting acid GER, providing more physiological and accurate information about reflux as a dynamic phenomenon than barium studies.

Barium Radiography

Barium studies are requested if an anatomical abnormality is suspected, such as hiatus hernia, oesophageal stricture, or gastric outlet obstruction. Although used historically for diagnosis, barium studies should not be used to diagnose or quantify GER, as gastro-oesophageal dynamics are only examined over a very short period of time.

Scintigraphy

This involves continuous imaging after feeding the patient a technetium 99m-radiolabelled meal. It is most commonly used to evaluate gastric emptying. It will also show non-acid reflux, and it is also specific (but not sensitive) for the detection of aspiration of gastric contents.

Endoscopy

Direct Laryngoscopy and Bronchoscopy enables a definite diagnosis of oesophagitis to be made, both macroscopically and histologically. Oesophageal strictures, hiatus hernia, Barrett’s oesophagus, and other conditions which cause epigastric pain or haematemesis may all be diagnosed.

DL & DB were performed on a large number of children known to have GERD, and 90% were noted to have at least 1 laryngotracheal abnormality.

Conservative Treatment of GERD

Positioning

The baby should be positioned for sleep with the head raised to 30° from the horizontal, best arranged by a folded blanket placed under the head end of the mattress. The seated position worsens GER.

Feeding

  • Avoid inappropriate feeding of infants — no huge feedings, and minimize air feedings/jostling during feeding.
  • No feeds 2 hours before bedtime, when possible
  • Eliminate chocolate and caffeine from the diet, and avoid tobacco exposure.
  • Thickening of feeds — by adding 1 tablespoon of dry rice cereal per ounce of milk formulae. This increases the caloric density from 20 to 30kcal/ounce, decreases episodes of vomiting / regurgitation, increases sleeping time, and decreases crying time. Alternatively, one may purchase prethickened formula in powder form.
  • Small, frequent feeds — Clearly indicated in infants who consume excessively large meals; of questionable benefit in everybody else..,

Medical Treatment of GERD

Prokinetic pharmacotherapy is the first line in young children (<2 years old) because GER is primarily a problem of motility in this age group. They work by increasing muscle tone at the lower end of the oesophagus, as well as hastening the passage of food through the digestive system. Acid suppression is added when eosophagitis is suspected.

Prokinetics

  • Cisapride (prepulsid) was once the first line medication in the treatment of GER in children. Several studies showed it was more effective than other prokinetic agents in the treatment of GER. Cisapride has minimal side effects with the exception of prolongation of the QT interval, and there have been anecdotal reports of deadly cardiac arrhythmias. Known risk factors for the development of these arrhythmias include preterm and newborn age, heart disease and electrolyte abnormalities.
  • Metoclopramide — side effects include nervousness, sleepiness, and dystonic reactions. These side effects are more common in children and respond quickly to withdrawal of the drug and valium.

Acid Suppressants

  • Antacids may be used for symptomtic relief; they should not be given long term or mixed in with infant formula because they can result in Aluminium toxicity and osteomalacia.
  • H-2 blockers (Cimetidine, Ranitidine, Famotidine) are usually adequate to achieve acid suppression in young children and adolescents.
  • Proton Pump Inhibitors (Omeprazole is the only PPI that has been studied in children) usually required in cases of severe chronic respiratory distress and neurologic disability. It should be given with or just before the first meal of the day. In small children, the granules should be delivered in an acidic medium, e.g., apple sauce or yogurt.

Surgery for GERD

Surgical treatment of GER (usually a Nissen fundoplication) may be inevitable if full medical treatment has failed, or if there is an oesophageal stricture or Barrett’s oesophagus at initial diagnosis. Such patients are best assessed jointly in a gastroenterological medical /surgical clinic at an early stage to consider each child’s problem individually. Surgery should be preceded by a full functional and anatomical assessment including review of barium studies, repeat oesophageal pH monitoring, motility and gastric emptying studies to enable appropriate surgical procedures to be selected after consultation with the parents. These may, for example, include a pyloroplasty or insertion of a feeding gastrostomy. Complications of surgical treatment include dumping, retching, intestinal obstruction, ‘gas bloat’, and recurrence of GER.

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