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Gastro-oesophageal Reflux Disease 311
Table 49.1: Possible pathological changes in GORD in relation to physiological tion. It is usually found in neurologically impaired children, in whom a
factors preventing reflux. differential diagnosis is often a neurological illness or fitting.
Mechanism preventing reflux Proposed contribution or Regurgitation of undigested food is a sign of late disease with stricture
pathology in GORD formation. If food has not made it into the stomach, stricture formation
should be suspected. This can also present as food bolus obstruction at
Oesophageal clearance Decreased in primary (e.g., oesophageal
atresia/tracheo-oesophageal fistule the level of the stricture. Stricture formation is present at diagnosis in
(OA/TOF)) or secondary (e.g., severe approximately 5% in Western countries. Where patients typically present
oesophagitis) oesophageal motility late, the incidence may be higher. One South African study demonstrated
disorders. 7
an incidence of 12% in children presenting to the surgical unit.
Length of intraabdominal Shortened in some congenital conditions Iron deficiency anaemia may be a late presenting symptom. In one
oesophagus including OA/TOF and sliding hiatus hernia.
African study, GOR was present in 44% of patients investigated for
Physiological lower Incriminated in transient lower oesophageal refractory iron deficiency anaemia. 8
oesophageal sphincter sphincter relaxation. Absent HPZ on Barrett’s oesophagus is metaplasia in the lower oesophagus from
manometry.
squamous to specialised intestinal columnar mucosa with goblet cells.
Diaphragmatic pinch-cock Abnormal anatomical configuration and/ It is a precursor of dysplasia and progression to adenocarcinoma. It is
effect of crura or muscular weakness (e.g., in congenital 9
diaphragmatic hernia, muscular dystrophies, present in approximately 5–10% of patients with GORD. A prevalence
scoliosis, and cerebral palsy) may contribute of 2.5 per 1000 is quoted in one paediatric population-based study
to reflux. in the United States. The incidence of Barrett’s is lower in African
10
3
Angle of His Altered in hiatus hernia and abdominal wall compared to Western countries; however, these patients tend to present
defects. May be altered by gastrostomy later and have a higher rate of progression to adenocarcinoma. There
2
placement and other abnormalities of are no specific symptoms associated with Barrett’s; it is discovered at
stomach anatomy.
endoscopy when biopsies are taken.
Gastric emptying Delayed gastric emptying in neurologically
impaired and congenital gastrointestinal Differential diagnoses
conditions contribute to, or worsen, reflux. The main differential diagnoses and the key features to differentiating
Mucosal folds (rosettes) Possibly only a minor contribution. them are:
• Malrotation and volvulus should be suspected if bilious vomiting
assumed in these cases, although occasionally a bile vomit may be is present. All patients with bilious vomiting should have an upper
present in GOR. gastrointestinal (GI) contrast meal with follow through looking for
Apnoeas and bradycardias are frequent presenting features in neonates malrotation.
and infants. In some infants, these symptoms may progress to acute • Urinary tract infection, meningitis and sepsis should be ruled out if
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life-threatening events (ALTEs). ALTEs are acute respiratory events there are signs of infection (urinary symptoms, fever, lethargy, and
characterised by apnoeas, bradycardias, and acute respiratory distress, and signs of meningism). It is important to rule out these out early or to
sometimes respiratory arrest. They are thought to occur during aspiration start appropriate treatment if present. If diarrhoea is present, gastro-
episodes from GOR. They can lead to the need for ventilation or they can enteritis is the likely diagnosis.
be present in neonates already ventilated on intensive care units.
• Intestinal obstruction usually presents with acute symptoms and is
Excessive vomiting can lead to failure to thrive, leading to
associated with distention and decreased passage of stool and flatus.
presentation with poor or absent weight gain.
Abdominal x-ray will reveal intestinal distention.
Older child
Vomiting and failure to thrive are the main presenting symptoms of Investigations
GORD in older children. Haematemesis is an uncommon presenting The diagnosis of GORD is made by using a combination of three main
feature, but may be present. Older children may be able to describe the investigative tools (pH study, contrast study, and upper GI endoscopy).
typical heartburn associated with GORD. This retrosternal pain may be The choice of first-line investigation is based on a combination of avail-
associated with a bitter taste in the mouth. ability, expertise, and symptoms. Each has its advantages and disadvan-
Respiratory symptoms of wheezing and recurrent pneumonias are tages, and any one or all three may sometimes be necessary. Other extra
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uncommon but recognised features. GORD should be suspected in investigations may be added as necessary.
children with these respiratory symptoms that are atypical and resistant A 24-hour pH study is considered by most as the gold standard
to treatment. Patients who have resistant wheezing not typically investigation for the diagnosis of GORD. Originally described by
responding to treatment should be investigated for GORD. Johnson and Demeester in 1974, a pH probe placed in the distal
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Physical Presentation oesophagus at the level of T10 is confirmed radiologically. The reflux
No physical findings are specific to GORD. Children who are failing index (percentage of total time that the oesophageal pH is less than 4)
to thrive may have evidence of weight loss and have a weight below is the main assessment used for diagnosis. If pH is less than 4 for 5%
the fifth centile or may be crossing down centiles. Children may have or more of the total time, the study is positive. Twenty-four–hour pH
features of syndromes associated with GORD. Some children may have studies have had up to 100% sensitivity and 94% specificity in some
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dental caries and poor general oral hygiene secondary to their reflux. studies. The apple juice pH study (using apple juice feeds instead of
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Neurologically impaired children and those with other syndromes may milk) has been shown to be more sensitive in babies on milk feed,
exhibit features of abnormal posturing suggesting Sandifer’s syndrome. in whom milk may partially neutralise stomach acid and cause falsely
high pH values in the presence of reflux.
Late and atypical presentations and specific presenting syndromes An upper GI contrast study can also demonstrate reflux and is used
Sandifer’s syndrome is constellation of abnormal posture (especially to assess the anatomy of the oesophageal hiatus. It can reveal a sliding
back arching) due to muscular spasm involving the back and neck or rolling hiatus hernia if present. The contrast study is not mandatory,
muscles. It may also present as torticollis. The abnormal posturing may but it is useful in those not responding to treatment and should be done in
be related to feeding or occur soon after a feed, suggesting the associa- those being considered for surgery. It can identify any stricture formation.