Diarrhoea And Constipation Flashcards
What is diarrhoea characterised by
IV stool frequency and volume and dec consistency
Patient perspective may vary
What do you need to determine in the history
Time scale
Acute
Chronic
What springs to mind if it is acute
Gastroenteritis
- travel
- diet change
- contact with D&V
- any fever pain
- HIV
- achlorhydria
Diff diag of chronic diarrhoea
Does it alternate with constipation suggest IBS
Dec weight, nocturnal diarrhoea, anaemia require close follow up for crohns coeliac or UC
Bloody diarrhoea causes
Shigella Campylobacter Salmonella E. Coli Amoebiasis UC Crohns Colorectal cancer Colon polyps Pseudo membraneous colitis Ischaemic colitis Fresh PR bleeding
Mucus in the diarrhoea
IBS
colorectal cancer
Polyps
Frank pus in diarrhoea
Suggest IBD
Diverticulitis
Fistula/abscess
Explosive diarrhoea
Cholera
Giardiasis
Yersinia
Rotavirus
Steatorrhoea
What is it like and what causes it
Inc has
Offensive smell
Floating hard to flush faeces
Pancreatic insufficiency
Biliary obstruction
Common causes of diarrhoea
Gastroenteritis Travellers diarrhoea C diff IBS Colorectal cancer Crohns, UC, coeliac
Less common causes of diarrhoea
Microscopic colitis Chronic pancreatitis Bile salt malabsorption Laxative abuse Lactose intolerance Ileal /gastric resection Overflow diarrhoea Bacterial overgrowth
Non GI or rare causes of diarrhoea
Thyrotoxicosis Autoimmune neuropathy Addison’s disease Ischaemic colitis Tropical sprue Gastroinoma Carcinoid Pellagra VIPoma Amyloid
Drugs that cause diarrhoea
Antibiotics Propranolol Cytotoxic Laxatives PPI NSAIDS Digoxin Alcohol
Signs to look for in a patient with diarrhoea
Dehydrated - dry mucous membranes, dec skin turgor,cap refill less than 2 seconds
Look for infective signs
Fever, clammy, BP low high HR
Cancer signs
Fever, night sweats, loss weight, clubbing, anaemia
IBD
Weight loss clubbing oral ulcers, rashes erythema nodosum
Prev Surgeries - scars, bags, masses
Goitre hyperthyroid signs
What exam must you do in diarrhoea
DRE
Masses or impacted faeces
What blood investigations are you going to do in diarrhoea
Blood tests - FBC, dec MCV iron def anaemia, inc MCV in alcohol abuse or dec B12 absorption in coeliac or crohns Eosinophilia if parasites Inc CRP infection, UC, crohns , cancer Dec k+ severe diarrhoea Metabolic acidosis in severe diarrhoea Dec TSH in thyrotoxicosis Coeliac serology
What stool tests are you going to do in diarrhoea
MC&S
Bacterial pathogens, ova cysts, parasites, c diff toxin,
Viral PCR
Fecal elastase - if suspect chronic pancreatitis
Fecal cal protection - UC not acute in case infective cause skew results
Management of diarrhoea
Depends on cause
Infective no work for food handlers till stool clear
Hospital outbreak wards may need closing
Oral rehydration if poss and better than IV
Severe IV fluids with electrolyte replacement
Anti diarrhoea loperamide after each loose stool not given in colitis risk of toxic megacolon
Avoid antibiotics unless systemic illness dec risk of c diff
Antibiotics associated diarrhoea may respond to probiotics
Investigations diarrhoea Lower GI endoscopy
Malignancy colitis in question
If acutely unwell, limited flex sig with biopsy
Full colonoscopy can assess more proximal disease if normal consider radiology or video capsule
What does c diff cause
Pseudomembraneous colitis
Signs of c diff
Inc temp Colic Diarrhoea with systemic upset Inc CRP, WCC Dec albumin Colitis
What type of colitis is seen in c diff
Yellow adherent plaques on non ulcerated inflamed mucosa - the pseudo membrane
What can c diff progress to
Toxic megacolon
And multi organ failure
Predictors of fulminant c diff
>70 year Prev c diff Anti peristalsis drugs used Severe leucocytosis Haemodynamic instability
Detection of c diff
Urgent test of suspicious stool
2 stage process
Rapid screening test for c diff protein or PCR
Followed by specific ELISA for toxins, AXR for toxic megacolon.
What makes you suspicious about a patients having c diff
The characteristic smell of the faeces
Treatment of c diff
Stop causative antibiotic if possible
Mild disease:metronidazole
Severe : vancomycin
Urgent colectomy maya be needed in toxic megacolon or if deteriorating
Recurrent disease treatment of c diff
Fecal transplant
Fidaxomicin minimally absorbed antibiotic
Constipation definition
Reflects pelvis dysfunction
Or inc transit time
Passage of 2 or less motions a week
Often passed with difficulty, pain, straining, and a sense of incomplete evacuation
What does constipation + rectal bleeding give concern for
Cancer
What does constipation + distension + active bowel sounds give concern for
Stricture / GI obstruction
What does constipation + menorrhagia give concern for
Hypothyroidism
Important history questions in those with constipation
Frequency Nature Consistency of stools Blood or mucus Diarrhoea alternating with constipation IBS recent change in bowel habit Is she digitalising the rectum or vagina to pass stool - rectocele front wall of the rectum bulges into the back wall of the vagina Diet Drugs Weight loss Pain Known anaemia
What is an important examination to do in constipation
PR
What tests are done in those with diarrhoea
Non in the young and mildly affected
More tests done with inc age
Blood FBC, ESR/CRP, U&E, +a2+, TFT.
Colonoscopy: if suspected colorectal malignancy
Transit studies, anorectal physiology, biopsy for Hirschorungs occasionally needed
What are the triggers that initiate tests
Weightloss
Abdominal mass
+PR blood
Iron def anaemia
Treatment for constipation
Conservative
Reassure, lifestyle diet, drink more water, exercise
Medical
Bulking agents, stimulant laxative,stool softener, osmotic laxative
Second line Prucalopride 5HT4 agonist with prokinetic properties, lubiprostone chloride channel activator inc intestinal fluid secretion
General chases of constipation
Poor diet +- lack of exercise Poor fluid intake/dehydration IBS Old age Post op pain Hospital environment
Anorectal disease cause of constipation
Anal or colorectal cancer Fissures, structures, herpes Rectal prolapse Proctalgia fugax Mucosal ulceration/neoplasia Pelvic muscle dysfunction / Levator ani syndrome
Intestinal obstruction causes of constipation
Colorectal carcinoma Stricture - crohns Pelvic mass - fetus fibroids Diverticulitis - rectal bleeding common Pseudo obstruction
Metabolic endocrine causes of constipation
Hypercalcaemia Hypothyroidism Hypokalaemia Porphyria Lead poisoning
Drugs that cause constipation
Opiates Anticholingerics Iron Some antacids Diuretics frusemide Calcium channel blocker
Neuromuscular causes of constipation
Slow transit from dec propulsive activity
Spinal or pelvic nerve injury
Aganglionosis - Chagas’ disease, hirschprungs
Systemic sclerosis
Diabetic neuropathy
Other causes
Chronic laxative abuse
Idiopathic slow transit idiopathic megarectum/colon
