Functional dyspepsia

Symptoms

• early satiety (most prevalent symptom)
  • Unless specifically asked about, it may often be missed or misinterpreted as bloating, discomfort or fullness after eating. 
  • These are also very common complaints even if meal size is not affected
• fullness
• epigastric pain or burning

red flag symptoms should prompt endoscopy:

• new onset in older age
• unintended weight loss
• vomiting
• bleeding
• iron deficiency anaemia
• family history of upper gastrointestinal cancer
• progressive dysphagia or odynophagia

• Rome IV diagnostic criteria for functional dyspepsia subtypes
  • Postprandial distress syndrome
    • Bothersome postprandial fullness or early satiety severe enough to impact on regular activities or 
    • finishing a regular-size meal for 3 or more days per week in the past 3 months, with at least a 6-month history.
  • Epigastric pain syndrome
    • Bothersome epigastric pain or epigastric burning 1 or more days per week in the past 3 months, with at least a 6-month history.
  • Note:
    • Both require the absence of evidence of organic, systemic, or metabolic disease that is likely to explain the symptoms on routine investigations (including at upper endoscopy).

Diagnosis

• Clinical
• need exclusion of structural gastrointestinal disease

Differentials

• GORD
  • Emerging data suggest GORD and functional dyspepsia are part of the same disease spectrum. 
  • Some patients with GORD who fail to respond to acid suppression with proton pump inhibitors may have functional dyspepsia so they should be asked about their symptoms
• irritable bowel syndrome
  • Symptoms of irritable bowel syndrome often overlap with those of functional dyspepsia, with epigastric pain and postprandial fullness often occurring with lower abdominal pain and bloating (diagnostic criteria in irritable bowel syndrome). 
  • However, unlike in irritable bowel syndrome, the symptoms of functional dyspepsia alone are not associated with a change in bowel habit. 
  • Both can arise after acute infectious gastroenteritis.
• Gastroparesis
  • often confused with functional dyspepsia but is rare
  • should be considered in patients with persistent vomiting or weight loss associated with dyspepsia.
  • nuclear medicine gastric-emptying test can be helpful in this setting

Pathophysiology

• not completely understood
• associated with upper gastrointestinal inflammation and motility disturbances, which may be triggered by an infectious or allergenic agent, or a change in the intestinal microbiome. 
• Slow gastric emptying occurs in 20% of cases

Treatment

Therapy	Functional dyspepsia subtypes
	Epigastric pain syndrome	Postprandial distress syndrome
Reassurance, explanation and advice to reduce stressDepression should be excluded by asking simple screening questions	+	+
Diet – regular low-fat meals, l ow FODMAP diet	+	+
Acid suppression	++	+
Prokinetics – can prolong the QT interval	+	++
Fundic relaxors	–	+
Tricyclic antidepressants – Consider amitriptyline 10–25 mg at night increasing to 50 mg if tolerated after 2–4 weeks	++	+
Rifaximin	+	+
Psychological therapy	+	+
– not useful + limited evidence of efficacy ++ efficacious

Abdominal migraine

• History
  • usually starts in childhood
  • commonly affects children under the age of 7
  • Most children who experience abdominal migraine grow out of it by their teens and eventually develop other migraine variants with headaches, but it can persist into adulthood
  • Patients with abdominal migraine often have a personal or family history of other types of migraine, similar undiagnosed episodes, or other episodic syndromes
• triggers
  • nitrates and other chemicals in processed meats, chocolate, and other foods
  • exhaustion/tiredness
  • Travel/motion sickness
  • Stress
  • missed meals
  • change in routine

• Relieving factors
  • rest (in 88% of patients)
  • sleep (in 64%)
  • analgesia (38%)
    • the same medicines used to treat other types of migraine also help with abdominal migraine, including – NSAIDs, anti-nausea medicines (like Stemitil or Ondansatron), triptan migraine drugs

• Clinical
  • Paroxysms of intense peirumbilical of diffuse pain lasting at least 1 hour at least twice in 6 months
  • Episodes are separated by weeks or month
  • Pain is incapacitating
  • is symptom-free and well between episodes, with a normal physical examination, stable body mass index, and expected developmental milestones
  • Associated with at least 2 of
    • Anorexia
    • Nausea – Very severe forms can have cyclical vomiting syndrome, where the affected person cannot stop vomiting for hours or even days.
    • Vomiting
    • Headache
    • Photophobia
    • Pallor
  • The attacks have the same four phases of migraine, with the acute phase lasting between 2-72 hours

• Diagnosis

• Clinically
• and requires no further investigation once “red flags” are excluded
• Children with abdominal migraine or other episodic syndromes usually have an excellent prognosis with no neurological or developmental deficits

• Treatment
  • In an observational clinic study, 60% of patients had parents with the same condition who were also relieved to understand it.
  •  Labelling abdominal migraine as medically unexplained or psychogenic pain may exacerbate depression and anxiety in the child and parents. 

Functional abnormal pain

• Criteria
  • Occurs > 4 times per month for > 2 months
  • Insufficient criteria for IBS, functional dyspepsia or abdominal migraine
  • Cannot fully be explained by another medical condition after appropriate evaluation
  • Does not solely occur with physiological events e.g. menses/eating etc..
  • Can coexist with other medical conditions such as inflammatory bowel disease
• Pain may be triggered or exacerbated during times of stress
  • e.g. school transitions, parental divorce and emotional trauma
• Alarm symptoms (see boxes below) are lacking

• The family history often is positive for IBS, reflux, constipation.
• child is well and functions normally between episodes but may have symptoms of
  • anxiety
  • depression 
  • separation anxiety
  • social phobias
  • specific phobias
  • generalized anxiety

• patients describe abdominal pain in emotional terms as
  • constant
  • not influenced by eating or defecation
  • involving a large anatomic area rather than a precise location, 
  • a continuum of painful experiences beginning in childhood or recurring over time

• Difficult cycle to break:
  • pain perception 🡪 worry about the pain and anticipation 🡪  worsening of pain / up-regulation of pain 🡪 pain perception
• Symptom-Related Behaviors
  • Expressing pain of varying intensity through verbal and nonverbal methods, may diminish when the patient is engaged in distracting activities, but increase when discussing a psychologically distressing issue or during examination
  • Urgent reporting of intense symptoms disproportionate to available clinical and laboratory data (eg, always rating the pain as “10” on a scale from 1 to 10)
  • Minimizing or denying a role for psychosocial contributors, or of evident anxiety or depression, or attributing them to the presence of the pain rather than to understandable life circumstances
  • Requesting diagnostic studies or even exploratory surgery to validate the condition as “organic”
  • Focusing attention on complete relief of symptoms rather than adaptation to a chronic disorder
  • Seeking health care frequently
  • Taking limited personal responsibility for self-management, while placing high expectations on the physician to achieve symptom relief
  • Making requests for narcotic analgesics when other treatment options have been implemented

Management 

• Need to Address all aspects of the biopsychosocial model of care. 
• Explain that FAP tends to improve with time and most children eventually grow out of it without any specific treatment other than distraction.

• Biological treatment: 
  • Child / parents may have noticed that analgesia often has little impact (this is because analgesia rarely impacts on visceral hypersensitivity).
  • Address constipation if history suggestive
  • Poor evidence for antispasmodics
  • Trial of PPI if there features of dyspepsia – but again set expectations that for functional dyspepsia, PPI often has little impact, due to different mechanism. Therefore addressing wider aspects of “pain theory” is important.
• Psychological treatment: 
  • Distraction has been found in studies to be most effective in symptom reduction, together with addressing concomitant anxiety symptoms. 
  • Studies have also found that parental and child acceptance of the functional nature of pain is best prognosticator of symptom improvement. 
• Social treatment: 
  • Explain ‘social’ aims of treatment e.g. going back to school 3 days a week after prolonged absence, going for a walk along the beach once a day after being bedbound.
  • Developing coping mechanisms and relaxation tips to deal with pain e.g. for younger children conceptualising pain as a creature in their tummy and breathing it out.
• Follow up 
  • Most children should be able to be followed up by their GP