Gastroenterology

Peritonitis / Perforation (see opposite) Path: Inflammation of viscus with extension to local peritoneum PC: Constant, worsened by movement, patient tends to lie down and shallow breathe

Obstruction / cOlic (see opposite) Path: Colic suggests excessive contraction of viscus, e.g. due to obstruction or infection PC: Waxes and wanes, patient tends to writhe and move around

Toxins a) Food poisoning b) Drugs, e.g. opioid addiction, antibiotics, anticholinesterases; radiotherapy c) Poisons: chronic lead poisoning, black widow spider bite

Endocrine crises a) Diabetic ketoacidosis b) Addison's c) Hypermetabolic state: thyrotoxicosis, phaeochromocytoma, carcinoid

Neuro-psychiatric a) Functional: Irritable bowel, anxiety, conversion disorder, Munchausen's syndrome b) Radiculopathy: shingles; spondylosis. N.B. dermatomal pattern and hyperesthesia c) Syphilis - 'tabetic crisis'

Thoracic origin (referred pain) Basal pneumonia, pulmonary embolism; myocardial infarction; pericarditis; thoracic radiculitis

Inherited a) Acute porphyria - colic b) C'1-esterase inhibitor deficiency: hereditary angioedema c) Familial Mediterranean Fever

Abdominal wall Rectus sheath haematoma (e.g. over-anticoagulation); myositis N.B. worsened by lifting head off pillow

Peritonitis PC: a) Localized peritonitis: constant localized pain, worsened by movement, patient tends to lie down and shallow-breathe,

e.g. appendicitis: umbilical —• RIF pain, constipation, later faeculent vomiting (generalized peritonitis) b) Sub-diaphragmatic: L shoulder-tip pain c) Retroperitoneal origin: vague localization or back pain; patient tends to sit up or move around

0/E:« Inspection: scaphoid-like abdomen (concave); distended - perforation or generalized peritonitis; flexed leg - retrocaecal appendicitis; Hippocratic facies (cold, moist, cyanosed) - generalized

• Palpation: abdominal rigidity; guarding (involuntary abdominal wall contraction); rebound (pain on release); Murphy's sign (tenderness on inspiration); pain per rectum - retrocaecal appendicitis

• Auscultation: absent bowel sounds (paralytic ileus) Ix: Erect CXR (air under diaphragm with oesophageal - bowel rupture); USS - free fluid in peritoneum or bowel

1. Hepatitis, abscess, hepatomegaly 2. Cholecystitis, cholangitis, cancer

1. Gastroenteritis, ischaemic 2. Aortic aneurysm, aortitis

1. Appendicitis, Crohn's, Meckel's diverticulum, caecal ca., diverticulitis

2. Mesenteric adenitis, Yersinia, TB, lymphoma, carcinoid

1. Oesophago-gastritis, peptic ulcer, rupture (Boerhaave's syn.)

2. Ca., lymphoma, coeliac 1. Splenic infarction, splenomegaly, EBV 2. Pancreatitis, ca., pseudocyst

1. Pyelonephritis 2. Psoas abscess, retroperitoneal sarcoma

1. Sigmoid colon diverticulitis, ca. 2. Pelvic inflammatory disease, salpingitis,

ectopic pregnancy, Mittleschmertz, menses (either iliac fossa and back)

Cystitis, testes torsion

Mechanical PC: a) Colic:

• Umbilical: small bowel • Lower half; lumbar: large bowel

b) Constipation + vomit c) May progress to bowel infarction \

and/or perforation, with peritonitis 0/E: a) Abdominal distension

b) Tinkling bowel sounds c) Hyperperistaltic movements

Paralytic PC: Constipation + vomit only 0/E: Absent bowel sounds {

Pseudo-Obstruction: reflex atony: post-surgery; trauma; retroperitoneal haematoma

2. Biliary: Cause: Calculi, ca. PC: colicky or constant; epigastric •

3. Renal-bladder: Cause: Calculi, ca. PC: Constant but migrates: loin —> flank —

-+ upper lumbar

suprapubic —> perineum

Diarrhoea Def 1. Reduction in stool consistency: essential

2. > 3x bowel opening per day, or > 250 g stool per day: not essential

Secretory - diarrhoea persists with fasting 1. Infection:

a) Food poisoning (toxin or organism preformed within food): • Toxin-mediated: Staph, aureus, Clostridium perfringens • Inflammation: Salmonella, Campylobacter

b) Gastroenteritis (i.e. organism colonizes and multiplies within bowel): • Toxin-mediated: cholera, £ ^//(enterotoxigenic: traveller's diarrhoea) • Inflammation: Shigella, £ ^//(enteroinvasive), Clostridium difficile, viral

2. Endocrine: a) APUDomas:

• Carcinoid • Islet-cell tumour (VIPoma, somatostatinoma, glucagonoma, gastrinoma) • Endocrine: medullary carcinoma thyroid (via calcitonin), phaeochromocytoma

b) Systemic: thyrotoxicosis, hypoadrenalism (Addison's), hypopituitarism Osmotic

1. Malabsorption - diarrhoea relieved by fasting Causes: i) Wall disease; ii) Bile salt malabsorption; iii) Pancreatic disease

2. Haemorrhage into bowel Inflammation or Ischaemia

1. Inflammatory bowel disease: ulcerative colitis, Crohn's, microscopic colitis 2. Ischaemia, inc. vasculitis

Laxatives or other drugs 1. Laxatives: • Secretory: phenolphthalein-containing, e.g. senna, bisacodyl

• Osmotic: Na, Mg or anion-containing 2. Antibiotics, esp. erythromycin; prokinetics 3. Radiation

Irritable bowel syndrome Rome criteria: a) Abdo-rectal pain: relieved by defaecation, radiates to thighs + back, bloating

b) Stool frequency: >3x/dayor < 3/week c) Stool form: hard pellets, watery, mucus Exclusion criteria: onset > 40 yrs; bloody stool; wt loss, + normal sigmoidoscopy

Neuropathy, autonomic e.g. diabetes; multiple sclerosis Gastrectomy + other surgery

• Short-bowel syndrome: extensive bowel resection; dumping syndrome: gastrectomy • Fistulae, e.g. jejuno-ileal bypass; anal sphincter disturbance

Structural Rectal adenoma, neoplasia, diverticular disease

Special 1. Alcohol, dietary indiscretion 2. Overflow - faecal impaction

/ v

Constipation Def 1. Bowel opening < 3x per week

2. Straining during defaecation > 25%

Obstruction a) Mechanical (colic) - see p. 103:

volvulus, adhesions, neoplasia, inflammation, strangulated hernia, intussusception, gallstone ileus

b) Pseudo-obstruction (reflex atony), e.g. post-surgery Pain

Anal fissure; 3° piles

Endocrine / Electrolytes 1. Endocrine: T41 , DM (DKA, 4 gastrocolic reflex) 2. Electrolytes: Ca i , K I , uraemia

Neurological 1. Brain: PD, CVA, MS 2. Spine: myelopathy, cauda equina, sacral plexopathy 3. Neuropathy: botulism, Hirschsprung's disease, Chagas' disease (Trypanasoma cruzi-S.America)

Inflammation or Ischaemia IBD or diverticulitis, or ischaemia

Toxins Opioids, anticholinergics, nicotine (ganglion blocker), aluminium salt (antacid), iron

Wall disease Systemic sclerosis or visceral myopathy

Irritable bowel syndrome Or other functional: disobeying call to stool, depression, idiopathic megarectum or megacolon

Diet or Dehydration Inadequate roughage, diuretics, starvation

Elderly, pregnancy

Bulking: faecal mass T —• peristalsis T: bran, ispaghula husk, methylcellulose Osmotic: fluidity of faeces t : lactulose (also probiotic), MgS04 Stimulant: GIT motility and secretion t : senna, bisacodyl, dioctyl; % colic, carcinoma ? Softeners: liquid paraffin Enemas: osmotic: PO4, Na citrate; stimulant: Na picosulphate softener: arachis oil Suppositories: stimulant: glycerol

Gastrointestinal: Gastro-oesophageal: reflux, ulcer, pyloric stenosis Pancreatic, liver, gall bladder disease Obstruction Peritonitis

Infection: GIT: gastroenteritis; hepatitis; visceral abscess Systemic: RTI (esp. tonsillitis, otitis media); UTI; septicaemia

Neoplasia: GIT: oesophago-gastric-duodenal carcinoma; lymphoma; amyloid Other: hypernephroma; hepatoma; ovarian Paraneoplastic

Toxins: Chemotherapy, opioids Antibiotics, aminophylline, antiarrhythmics (esp. digoxin), L-DOPA Alcohol

Obstetric: Pregnancy Ophthalmic: Acute closed-angle glaucoma Neurology: Labyrinthitis, Meniere's, brainstem-cerebellar disease, e.g. MS

ICP t ; meningo-encephalitis; tabetic crisis Migraine; vasovagal syncope Autonomic neuropathy: diabetes, acute intermittent porphyria Psychiatric: bulimia or anorexia nervosa, psychogenic

DKA gastroparesis Addison's crisis Thyrotoxicosis

Systemic: Respiratory failure: acidosis Cardiac failure, esp. right-sided: bowel oedema Renal or liver failure: uraemia

Physiology

CNS: cerebrum, meninges,

hypothalamus

Semi-circular canals:

motion sickness

Circulating toxins: endotoxin,

drugs, acidosis

GIT and heart: 5-HT released by gut

enterochromaffin cells, or stimulation of

mechano-/ chemoreceptors

CTZ = Chemoreceptor

Vomiting centre: nucleus tractus solitarius

medullary reticular formation

Efferents: Xth cranial nerve

Rx 1. Underlying cause 2. Supportive: hydration (PO/IV ), NaCI replacement 3. Anti-emetics: select according to receptor-type relevant to cause

A. 1.2.3. Muscarinic (Ach) receptor antagonist: hyoscine

Indication: motion sickness, GIT causes $ : Sedation, dry mouth

Histamine type 1 receptor antagonist: cyclizine, cinnarizine, promethazine Indication: motion sickness, GIT, cardiac causes

& : Sedation, other anti-cholinergic side-effects Dopamine type 2 receptor antagonist: metoclopramide, domperidone

Indication: most causes, esp. gastro-oesophageal reflux (as pro-motility effect) % : Sedation, extrapyramidal reactions (less likely with domperidone), diarrrhoea

5-HT type 3 receptor antagonist: ondansetron, granisetron Indication: most causes, esp. chemotherapy, post-surgery, neoplasia, MS

% : Headache, constipation

Others: • Steroids - for neoplasia • Nabilone (cannibinoid - acts on opiate receptors) - for chemotherapy, MS

a) Influenza or coryza (coronavirus, adenovirus, rhinovirus, enteroviruses, coxsackie) b) Exanthems: rubella; measles; hand, foot and mouth disease: coxsackie A16, enterovirus 71 c) EBV: PC: pearly-white exudate + palatal petechiae d) Other: parainfluenza, croup, haemorrhagic fever

2. Bacterial - localized a) Streptococcus pyogenes (p-haemolytic; Lancefield group A);

also causes tonsillitis and quinsy (peritonsillar abscess), and rheumatic fever b) Staphylococcus aureus: facial erysipelas c) Haemophilus influenzae type b - epiglottitis d) Anaerobes: Fusobacterium necrophorum (necrobacillosis): Lemierre's disease;

also causes jugular thrombophlebitis; lung and brain abscesses 3. Bacterial - general

a) Pneumonia: Streptococcus pneumoniae, Mycoplasma, Chlamydia, tularaemia, brucellosis b) GIT: typhoid, leptospirosis c) STD: gonorrhoea, 2° syphilis d) Neurological:

• Diphtheria (bull neck, stridor, brassy cough, palatal weakness, myocarditis) • Meningococcus, listeriosis (associated meningitis)

4. Fungal: oral candidiasis

Neoplasia Carcinoma of oral cavity or pharynx

Toxins 1. Smoking, alcohol, pollution, e.g. H2S 2. Drugs: thionamides (carbimazole, propylthiouracil) due to neutropenia; lamotrigine

Vit B12, folate, iron deficiency - cause mucositis, glossitis, cheilitis Autoimmune

1. Viral a) Herpangina: enterovirus, coxsackie, echovirus - children b) Herpes: HSV-1 (acute gingivostomatitis or recurrent); VZV; EBV c) HIV: acute gingivitis, ulceration; glandular fever-like illness

2. Bacterial a) TB: tip-of-tongue ulcers b) STD: • Gonorrhoea

• Syphilis (1°-chancre; 2°-snail-track ulcer; tongue; 3°-gumma) c) Anaerobic:

• Vincent's angina = symbiosis of Borrelia vincentii + Bacteroides • Actinomycoses: assoc. with tooth extraction or jaw fracture:

inspection reveals yellow sulphur granules 3. Fungal

Histoplasmosis: ulcerative nodules, laryngitis, fever Neoplasia

Toxins 1. Sulphonamides, chloramphenicol, cytotoxics: neutropenia 2. Stevens-Johnson syndrome, erythema multiforme

Epi: 20% lifetime incidence; assoc. with stress, menses PC: Painful, single or cluster of ulcers with grey base and red surround Types: minor (1-5 mm); major (5-15 mm); herpetiform (200 x 1 mm)

Nutritional 1. Haematinics: Vit B, folate, Fe deficiency 2. Vit C deficiency 3. Malabsorption, e.g. coeliac

Autoimmune Most are aphthous ulcers (i.e. painful, gray base, red surround)

1. Behpet'syn.: orogenital ulceration + anterior uveitis + arthritis 2. SLE 3. Seronegative arthropathies: IBD (esp. Crohn's); Reiter's syndrome 4. Pemphigus (ruptured bullae); pemphigoid (bullae); lichen planus (white striae)

Extrinsic

1. CVA: extensive small-vessel disease 2. Parkinson's, esp. progressive supranuclear palsy 3. Psychiatric 'globus pharyngeus'

Bulbar palsy (lower motor neurone) 1. Brainstem: syringobulbia, infarction (lateral medullary syn), MS 2. Motor neurone disease (partially upper-motor neurone), polio 3. Peripheral autonomic neuropathy:

diphtheria, GBS, Chagas' disease Muscular/myenteric plexus

1. NMJ: myasthenia, botulisim 2. Myopathy 3. Ganglion/peristalsis dysfunction:

a) Scleroderma/CR.E.S.T. b) Spasm: lower oesophageal (achalasia) or diffuse

Oral Pharyngitis and oral ulcers cause painful swallowing (odynophagia) with secondary dysphagia

Foreign body, large bolus

Intrinsic 1. Upper:

a) Pharyngeal pouch b) Post-cricoid web

2. Middle: a) Oesophagitis b) Oesophageal stricture c) Oesophageal carcinoma

3. Lower: a) Hiatus hernia b) Schatzki ring

Bone: cervical spondylosis U: dysphagia LUsoria: vascular compression:

aberrant R subclavian artery, aortic aneurysm, mitral stenosis (enlarged left atrium)

Lymphadenopathy Goitre Infection: retropharyngeal abscess Neoplasia: pancreatic cancer

Neuromuscular 1. Solids = liquids; nasal regurgitation 2. Aspiration occurs while attempting to swallow 3. Other: diplopia, ataxia

Oral Odynophagia

Pharynx - oesophagus 1. Solids > liquids 2. Aspiration unrelated to swallowing 3. Other: chest pain; dyspepsia, hiccups (lower oesophagus)

Neuromuscular Other neurological deficits e.g. ataxia, dysarthria, Horner's syndrome

Oral Erythema, apthous ulcers, Candida

Pharynx-oesophagus 1. Hoarse:

• Laryngitis (gastro-oesophageal reflux) • Left recurrent laryngeal nerve palsy (carcinoma, lymph nodes)

2. Respiratory Sx: Right middle lobe consolidation (aspiration pneumonia); unilateral wheeze (main bronchus compression)

Neuromuscular Videofluoroscopy: identifies weakness or incoordination

Pharynx-oesophagus 1. Barium swallow 2. 0GD 3. Oesophageal motility + manometry studies

1. Psychiatric 'globus pharyngeus' • Pt. feels lump in throat at level of cricoid • Middle-aged female, depression

2. Achalasia: chest pain Pharynx-oesophagus

1. Pharyngeal pouch: elderly 2. Post-cricoid web:

occurs as part of Plummer-Vinson or Paterson-Brown-Kelly syndrome, also characterized by Fe-deficiency anaemia, koilonychia, glossitis, and risk of squamous cell carcinoma

1. Mallory-Weiss tear • Mucosal break < 2 cm proximal to gastro-oesophageal junction • Due to forceful vomiting, esp. males drinking alcohol

2. Surgery, ERCP (haemobilia), aorto-duodenal fistula, 2 ° aortic aneurysm / repair 3. Hypovolaemic shock: ischaemic, stress ulcer in stomach

Angiodysplasia+ other vascular anomalies 1. Angiodysplasia

Dilated vessel complexes in clusters 2. Hereditary haemorrhagic telangiectasia

• Dilated vessels over entire bowel wall • Autosomal dominant: endoglin mutation (TGF-receptor on endothelium) • PC: haematemesis, haemoptysis (pulmonary AVM), cerebral abscess, epistaxis

3. Other • Dieulafoy lesion = protruding large submucosal vessel • Watermelon stomach = gastric antral vascular ectasia • Vasculitis, e.g. PAN

Generalized bleeding disorder 1. Connective tissue defects: Ehlers-Danlos syndrome; pseudoxanthoma elasticum 2. Coagulopathy, e.g. chronic renal failure, warfarin

Epistaxis; or Dental; oropharynx; epistaxis or haemoptysis (swallowed blood)

Exogenous Factitious

Ix for any GIT bleeding Bloods

1. U + E: urea t T with upper GIT lesion; ARF 2. FBC: chronic or acute 3. Clotting times

+ group + save +X-match as appropriate

Radiology 1. Barium enema ± follow-through 2. Tc-labelling: (detects bleeding > 0.5 ml/min):

colloid / autologous RBCs 3. Selective mesenteric angiogram

Special 1. Endoscopy: needs good bowel prep. (e.g. P04 enema) 2. Laparotomy; investigative ileo/colostomy

Diverticulae 1. Colonic: diverticular disease

PC: Pellety stool, pain, pr bleeding + diarrhoea 2. Ileal: Meckel's diverticulum

PC: Childhood bleeding 3. Jejunal:

PC: Usually present with malabsorption + Vit B12 deficiency due to bacterial overgrowth

Rectal 1. Piles: PC: blood separated from stool; painless unless thrombosed 2. Solitary rectal ulcer; proctitis, e.g. 2° to gonorrhoea

Infection 1. Bacterial: Salmonella, Campylobacter, £ coll

pseudomembranous colitis, TB 2. Other: HIV, CMV, Candida 3. Parasite: amoebic dysentery, hookworm (melaena)

Polyps - Benign a) Hyperplastic, esp. rectal b) Hamartomatous, e.g. Peutz-Jeghers' syndrome

PC: Obstruction, intussusception —• strawberry-jelly stool Polyps - Neoplastic

Adenoma — carcinoma Inflammation

1. Ulcerative colitis: bloody diarrhoea 2. Crohn's: ileal bleeding - uncommon

Neoplasia Carcinoma, lymphoma, Kaposi's sarcoma

Gastric-upper bowel bleeding PC: Melaena (black, tarry stool), or bloody, if rapid transit

Trauma Surgery, colonoscopy, e.g. polypectomy; radiation colitis

Arterial / Angiodysplasia / AVM 1. Ischaemic colitis 2. Angiodysplasia 3. AVMs, hereditary haemorrhagic telangiectasia

Pseudomembranous colitis / Parasites see under Infection

Systemic 1. Coagulopathy 2. Amyloid

Abdominal Examination 2. Face

a) Eyes: • Conjunctivae:

pallor - anaemia • Cornea: jaundice • Xanthelasma: lipids

b) Mouth: • Pigmentation

(Peutz-Jeghers' Syndrome Addison's)

• Telangiectasia (HHT, scleroderma)

• Glossitis, cheilitis (Vit B12 or Fe def,

• Ulceration: Crohn's (also swollen lips), Candida (white plaques -

check genitalia) Oral hairy leukoplakia

(lymphoma, HIV) c) Parotid enlargement:

liver failure

1. Hands a) Nails:

• Clubbing (cirrhosis, colitis, coeliac, lymphoma)

• Leuconychia (hypoalbuminaemia • Sclerodactyly, telangiectasia

(scleroderma) b) Palms:

• Asterixis (liver failure) • Dupuytren's contracture

(alcoholism) • Hyperkeratotic-oesophageal

cancer (tylosis) c) Forearms:

• AV-fistula thrill, excoriations: chronic renal failure

• Tattoos: hepatitis or HIV risk

3. Heck a) JVP t : R-sided cardiac failure as a cause of cirrhosis b) Lymphadenopathy:

• Lymphoma, TB, HIV • Gastric cancer: supraclavicular LN • Troisier's sign

c) Goitre (dysphagia, T4-toxicosis causes diarrhoea)

4. Abdomen

a) Inspection of trunk and back Skin of trunk and back: • Stigmata of chronic liver disease:

spider naevi, gynaecomastia, testis atrophy, sexual hair loss, caput medusa, dilated abdominal veins

• Uraemic frost: brown-yellow tinge Scars, stoma, sinuses, striae Masses, e.g.