Gastro Flashcards
Define coeliac disease
Primarily digestive disorder
Most common genetically related food intolerance
Life-long gluten-sensitive autoimmune disease of small intestine
Epidemiology of coeliac disease
Approx 1%
Often seen more in diabetes, autoimmune disorders and relative of Coeliac disease individuals
Pathophysiology of coeliac disease
Combination of immunological responses to an environmental factor (gliadin) and genetic factors (HLA-DQ2/DQ8)
Body’s immune system overreacts to in food
- damages villi of small intestine
T-cell mediated immune disorder
- anti-gluten CD4 T cell response
- anti-gluten antibodies
- autoantibodies against tissue transglutaminase
Epithelial cell destruction and villous atrophy
Which types of cereal is gluten found in?
Wheat
Barley
Rye
Presentation of coeliac disease
Classical form
- 9-24 months
- malabsorption, failure to thrive, weight loss, loose stool, steatorrhea, anorexia, abdo pain, abdo distention, muscle water
- histology reveals crypt hyperplasia and villous atrophy
Atypical form
- no intestinal symptoms a/w extra-intestinal symptoms
- osteoporosis, peripheral neuropathy, anaemia and infertility
- positive coeliac serology, limited abnormalities of small intestine
Latent form
- presence of predisposing gene
- normal intestinal mucosa and possible positive serology
Silent form
- damaged small intestinal mucosa
- positive serology but no clinical symptoms
Potential
- normal mucosal morphology, positive autoimmune serology and asymptomatic
- genetically predisposed to develop at some point
Extra-intestinal symptoms of coeliac disease
Dermatitis herpetiformis Dental enamel hypoplasia Osteoporosis Delayed puberty Short stature Iron-deficient anemia - resistant to oral Fe Liver and biliary tract disease Arthritis Peripheral neuropathy, epilepsy, ataxia
Differential diagnosis of coeliac disease
Tropical sprue Cystic fibrosis IBD Post-gastroenteritis Autoimmune enteropathy Eosinophilic enteritis
Investigations for coeliac disease
Serology
- test total immunoglobulin A (IgA) and IgA tissue transglutaminase (tTG)
- if IgA tTG weakly positive then use IgA endomysial antibodies
- must have gluten in diet at period of testing and for at least 6 weeks before
Biopsy
- duodenal biopsy gold standard to diagnose
- ensure findings improved on gluten free diet or diagnose different GI disorder
Who should be offered serological testing for coeliac disease
Children with
- persistent unexplained abdo or GI symptoms
- faltering growth
- prolonged fatigue
unexpected weight loss
- severe or persistent mouth ulcers
- unexplained iron, vit B12 or folate deficiency
- type 1 diabetes
- autoimmune thyroid disease
- IBS
First degree relatives of people with coeliac disease
Marsh classification of coeliac disease biopsy
Stage 0 = normal
Stage 1 = increased intraepithelial lymphocytes
Stage 2 = increased inflammatory cells and crypt hyperplasia
Stage 3 = all of the above plus mild to complete villous atrophy
Management of coeliac disease
Lifelong diet free of gluten
Supplementation if obvious malabsorption
Annual follow up to check symptoms, diet compliance, development, growth and long term complications
Complications of coeliac disease
Anaemia
Osteopenia/osteoporosis
Refractory coeliac disease - symptoms persist despite diet
Malignancy
Fertility problems / adverse events during pregnancy
Depression/anxiety
Define cow’s milk protein allergy
Immune-mediated allergic response to naturally-occuring milk proteins casein and whey
Epidemiology of cow’s milk protein allergy
Most common childhood food allergies
7% of formula/mixed-fed infants
Pathophysiology of cow’s milk protein allergy
IgE-mediated
- Type-1 hypersensitivity reaction
- CD4+ TH2 stimulate B cells to produce IgE antibodies against cow’s mild protein
- trigger release of histamine and other cytokines from mast cells and basophils
Non-IgE-mediated
- involves T cell activation against cow’s milk protein
Risk factors for cow’s milk protein allergy
Personal hx of atopy
Family hx of atopy
Exclusive breastfeeding is possible protective factros
Clinical features of IgE-mediated cow’s milk protein allergy
Acute and rapid onset (2 hours post ingestion) Skin reactions - pruritus - erythema - acute urticaria - acute angioedema GI symptoms - angioedema - oral pruritus - N+V - colicky abdo pain - diarrhoea Resp symptoms - lower - cough, chest tightness, wheezing or SOB - upper - nasal itching, sneezing, rhinorrhoea or congestion
Clinical features of Non-IgE-mediated cow’s milk protein allergy
Non-acute and generally delayed Skin reactions - pruritus - erythema - atopic eczema GI symptoms - GORD - loose or frequent stools - blood / mucus in stool - abdo pain - infantile colic - food refusal or aversion - constipation - perianal redness - pallor and tiredness - faltering growth Lower resp tract symptoms - cough - chest tightness - wheezing - SOB
Features of an allergy focused history
Personal or family history of atopy Diet and feeding hx of infant Mother's diet if breastfed Any previous management used for symptoms Which milk/foods Age of onset Speed of onset following exposure Duration Severity and frequency of occurrence Setting of reaction Reproducibility of symptoms
Differential diagnosis of cow’s milk protein allergy
Food intolerance Allergic reaction to other food/non-food allergens Anatomical abnormalities such as Meckel's diverticulum Chronic GI disease - GORD - coeliac disease - IBD - constipation - gastroenteritis Pancreatic insufficiency UTI
Investigations for cow’s milk protein allergy
Usually clinically diagnosed
Blood test looking for specific IgE antibodies - RAST
- low specificity resulting in false positives
Skin prick test
Refer for IgE antibody test for cow’s milk protein allergy
Faltering growth with symptoms
One or more acute systemic or severe delayed reactions
Confirmed IgE mediated food allergy with asthma
Persistent parental suspicion of a food allergy despite lack of clear hx
Clinical suspicion of multiple food allergies
Management of cow’s milk protein allergy
Avoidance of cow’s milk
- including from mother’s diet if breastfeeding
- elimination diet required for at least 6 months or until infant 9-12 months
- extensively hydrolysed formula - cheaper
- made from cow’s milk but casein and whey broken down into smaller peptides
- 90% of children ok
- amino acid formula - more expensive
- soy-based formulas not recommended in infants <6 months due to weak oestrogenic effects
Nutritional counselling and regular monitoring of growth
Complications of cow’s milk protein allergy
Malabsorption Reduced intake Chronic iron-deficiency anaemia Faltering growth Anaphylaxis - rare
Define GORD
Gastro-oesophageal reflux (GOR)
- passage of gastric contents into oesophagus
- normal in infants if asymptomatic
Gastro-oesophageal reflux disease (GORD)
- presence of symptoms or complications from reflux
Regurgitation (posseting)
- reflux of stomach contents beyond the oesophagus
Epidemiology of GORD
Regurgitation extremely common - occurs in approx 40% of infants
Usually appears in first 2 weeks of life
Pathophysiology of GORD
LOS muscle tone too low
-> uncontrolled reflux of stomach content
Features of infants that can contribute to GORD
Short, narrow oesophagus
Delayed gastric emptying
Shorter, lower oesophageal sphincter that is slightly above the diaphragm
Liquid diet and high calorie requirement, distending the stomach and increasing pressure gradient between stomach and oesophagus
Larger ratio of gastric volume to oesophageal volume
Spending significant periods recumbent
Risk factors for GORD
Prematurity
Parental history of heartburn or acid regurgitation
Obesity
Hiatus hernia
History of (repaired) congenital diaphragmatic hernia
History of (repaired) congenital oesophageal atresia
Neurodisability - cerebral palsy
Clinical features of GORD
Distressed behaviour - excessive crying, unusual neck postures, back-arching
Unexplained feeding difficulties - refusing feeds, gagging, choking
Hoarseness and/or chronic cough in children
A single episode of pneumonia
Faltering growth
If child is able to they may report retrosternal or epigastric pain
Take feeding hx - check technique, calculate volume of milk and relationship between symptoms and feeds
Differential diagnosis of GORD
Pyloric stenosis - frequent forceful vomiting in < 2 months old Intestinal obstruction - bile-stained vomit Acute surgical abdo issue - abdo distention, tenderness or palpable mass Upper GI bleed - haematemesis Sepsis - altered responsiveness, severe prolonged vomiting, petechial rash, bulging fontanelle Raised ICP - rapid increasing head circumference, persistent headache and vomiting following periods of recumbence Bacterial gastroenteritis - blood in stool Cow's milk protein allergy - blood in stool - chronic diarrhoea UTI
Management of GORD
Effortless regurgitation
- reassurance
Breastfed
- alginate (Gaviscon) mixed with water immediately after feeds
Formula-fed
- ensure infant not over-fed - no more than 150ml/kg/day
- decrease feed volume by increasing frequency
- use feed thickener
- stop thickener and start alginate added to formula
If no improvement after 2 weeks trial PPI or histamine antagonist - omeprazole or ranitidine
Complications of GORD
90% spontaneously resolve by 1 year
Reflux oesophagitis
Recurrent aspiration pneumonia
Recurrent acute otitis media - >3 episodes in 6 months
Dental erosion - especially in children with neurodisability
Apnoea
Apparent life-threatening events (ALTE): a combination of symptoms including apnoea, colour change, change in muscle tone, choking and gagging
Define gastroenteritis
Inflammation of stomach and intestines
Infective gastroenteritis is a temporary disorder due to an enteric infection
- Most commonly caused by viruses, but can also be due to bacterial or parasitic infection
Typically characterised by sudden onset diarrhoea with or without vomiting
Epidemiology of gasteroenteritis
Viral causes
- rotavirus
- most common in infants - immunity long lasting
- oral vaccine part of UK vaccination programme at 8-12 weeks
- norovirus
- commonest in all age groups
- spread by faecal oral route or by environmental contamination
- adenovirus
Bacterial
- campylobacter
- bloody diarrhoea
- consumption of undercooked meat and unpasteurised milk
- Escherichia coli
- transmitted through contaminated food, person-to-person and contact with infected animals
Clinical features of gastroenteritis
Sudden onset of loose/watery stool with or without vomiting
Abdominal pain/cramps
Mild fever
Recent contact with someone with diarrhoea or vomiting
Groups at high risk for dehydration
Young children - under 6months
Children who have passed >5 diarrhoeal stools in the last 24 hours
Children who have vomited >2x in the last 24 hours
Children who have stopped breastfeeding during the illness
Differential diagnosis of gastroenteritis
Temperature higher than 38oC if < 3months or higher than 39oC if >3months Breathlessness or tachypnoea Altered GCS Meningism Blood/mucous in stool Bilious (green) vomit Severe/localised abdominal pain Abdominal distension or guarding
Investigations for gasteroenteritis
A stool sample should be sent for microbiological investigations if
- Septicaemia is suspected or
- blood and/or mucus is present in the stool or
- the child is immunocompromised
Do not routinely perform blood tests however measure Na+, K+, Cr, Ur and glucose if
- IV fluids are going to be used
- There are symptoms/signs of hypernatraemia - jittery, increased muscle tone, hyperreflexia, convulsions, drowsiness or coma
Measure acid-base status and chloride concentration is shock is suspected.
