1.1. Diarrohea Flashcards
What is the difference between Diarrhoea and Gastro-enteritis?
- Diarrhoea - subjective (A change in pattern indicated Diarrhoea)
- Gastro-enteritis - objective (Diarrhoea + other symptoms)
What changes during Diarrhoea?
- Fluidity of the stool
- Frequency of the stool
What are the features of Gastro-enteritis?
- 3+ loose stools per day
- Accompanying features
Is a positive stool culture needed to have Gastro-enteritis?
No, but need to have 3+ loose stools per day the other symptoms
Note - It is an objective finding but clinical, not always biological
What is Dysentery?
Large bowel inflammation due to infection
What is present with Dysentery?
- Bloody stools
- A lot of pain
Note - it is quite obvious when someone has contracted Dysentery
What is the name of the chart which stools are measured against?
The Bristol Stool Chart:
1 - Separate hard lumps, hard to pass
4 - Sausage / Snake like, smooth and soft
7 - Watery, no solid pieces, entirely liquid
What are the types of Diarrhoea?
- Non-inflammatory Diarrhoea (e.g. cholera)
- Inflammatory Diarrhoea (e.g. Shigella Dysentery)
- Mixed-picture Diarrhoea (e.g. C. Difficile)
What mediates Non-inflammatory Diarrhoea?
It is secretory-toxin mediated - the toxin affects the way you transport Cl and Na:
1. Cholera - increases cAMP levels and therefore Chloride secretions (Salt shifts into the gut and takes the fluid with it)
2. Enterotoxigenic E. Coli (Travelers’ Diarrhoea)
What is the clinical signs / symptoms of Non-inflammatory Diarrhoea?
- Frequent watery stools
- Little abdominal pain
What is the mainstay of therapy for Non-inflammatory Diarrhoea?
Re-hydration Therapy
What mediates Inflammatory Diarrhoea?
Inflammatory toxin damage and mucosal destruction
What causes Inflammatory Diarrhoea?
- Bacterial infection
- Amoebic dysentery
What is assessed in Inflammatory Diarrhoea?
- Symptoms and their duration (History)
Note - If > 2/52, unlikely to be infective cause - Risk of food poisoning (Dietary, Contact, Travel History)
- Hydration (Postural B.P. (will drop by 20mmHg), Skin Turgor, Pulse)
- Features of inflammation (SIRS/Sepsis) (Fever, Raised WCC)
What needs to be assessed if there is a lot of fluid loss, due to Inflammatory Diarrhoea?
Hyponatraemia
What investigations would you perform in Inflammatory Diarrhoea?
- Stool culture (Most important)
- Blood culture
- Renal function (Assess the Na and K loss)
- Blood count (Neutrophilia, Haemolysis)
- Abdominal X-Ray (if the abdomen is distended and tender)
Note - The X-Ray would be looking for toxic dilation of the bowel
What is the differential diagnosis for Inflammatory Diarrhoea?
- Inflammatory Bowel Disease
- Spurious Diarrhoea- secondary to constipation
- Carcinoma
- Sepsis outside of the Gut
If Diarrhoea is caused by Sepsis outside of the Gut occurs, how will the patient present?
- Features of infection for another system
- Lack of abdominal pain / tenderness
- No blood / mucus in the stool
What is the treatment of Inflammatory Diarrhoea?
- Rehydration Therapy
- Antimicrobials may be appropriate
What is the most common Mixed-picture Diarrhoea?
Clostridium Difficile (C. Diff) Diarrhoea
What is the range of C. Diff infection?
- Mild Diarrhoea
- Severe Colitis
What is the main risk factor for C. Diff infection?
Prior antibiotic therapy with the “4 ‘C’ Antibiotics:
1. Cephalosporins
2. Co-Amoxiclav
3. Clindamycin
4. Clarithromycin
What is the pathology of C. Diff infection?
C. Diff produces:
1. Enterotoxin (A)
2. Cytotoxin (B)
These cause damage to the colonocytes and cause a local inflammatory response
What is the best prevention of C. Diff infection?
- Reduction in broad spectrum antibiotic prescribing
- Avoid “4 ‘C’ Antiobiotics:
- a) Cephlasporin
- b) Co-Amoxiclav
- c) Cindamycin
- d) Clarithromycin
- Anitmicrobial Management Team (AMT) and local antibiotic policy
- Isolate symptomatic patients
- Wash hands between patients
What is the best management of C. Diff infection?
- Stop precipitating antibiotics (if possible)
- a) If no severity markers - Oral Metronidazole
- b) If 2+ severity markers - Oral Vancomycin
Note - Vancomycin is not absorbed through the GI tract and so is useful for this - Fidaxomicin (new and expensive)
- Stool transplant
- Surgery may be required
Is Parasitology, related to Diarrhoea common in the UK?
No
What forms of Parasites are associated with Diarrhoea?
- Protozoa
- Helminths
In relation to Diarrhoea, what are the 2 most common Parasites found in the UK?
- Giardia Lamblia
- Cryptosporidium Parvum
With Giardia Lamblia infection, what is the:
1. Most common route of infection?
2. Clinical Signs / Symptoms?
3. Treatment?
- Contaminated Water
- a) Diarrhoea
- b) Malabsoprtion
- c) Failure to Thrive
- Metronidazole
With Cryptosporidium Parvum infection, what is the:
1. Most common route of infection?
2. Condition this is recognized alongside?
3. Treatment?
- Contaminated Water (with animal faeces)
- AIDS (Advanced HIV infection)
- No treatment
Where can other parasites, causing Diarrhoea, come from?
They can be imported and so there is a large range of possibilities
What is the most common imported parasite?
Entamoeba Histolytica (more commonly known as Amoebic Dysentery)
How is Entamoeba Histolytica (Amoebic Dysentery) treated?
Metronidazole
How are parasite infections, causing Diarrhoea, diagnosed?
Using Microscopy (Send a stool with request for Parasites, Cysts and Ova (P, C and O)):
1. Giaradia Lamblia - cysts seen on stool microscopy
2. Cryptosporidium Parvum - cysts seen on stool microscopy
3. Entamoeba Histolytica (Amoebic Dysentery) - Cysts seen in asymptomatic patient
What can be a long term complication of Entamoeba Histolytica (Amoebic Dysentery)?
Amoebic Liver Abscess
What is the most common Viral causes of Diarrhoea in children (especially under 5’s)?
- Rotavirus
- Adenovirus
When are viral infections, causing Diarrhoea, most commonly seen?
Winter
How are viral infections, causing Diarrhoea, diagnosed?
Antigen detection
Note - this is a very common cause but it is not looked for as it is self-limiting
What is used in prevention of Rotavirus infection?
Vaccine
What is the most common Viral causes of Diarrhoea in adults?
Noroviruses - previously known as:
1. Small round structured viruses (SRSV)
2. Norwalk like viruses
3. Winter vomiting disease
How is Norovirus diagnosed?
PCR
How infectious is Norovirus?
Very (spread via contact / aerosol):
1. Can cause ward closures
2. Strict infection control measures are needed
