cases in infectious decease

Case 1
A 78 year old gentleman presented to Leicester ED in the early hours of the morning with profuse diarrhoea. He is seen by an SHO and admitted up to the Acute Medical Unit (AMU) for review. The SHO who saw the patient was very busy. His brief clerking is below.
Presenting Complaint: 2 day history of diarrhoea (6 times a day) and associated abdominal discomfort.
No recent holidays
Had take -away for dinner 2 days ago
Past medical History; Osteoarthritis, hypertension, gall stones
Drug History; Paracetamol, dihydrocodeine, bendroflumethiazide
No known allergies
Family History; nil
Social History; Lives with wife, retired teacher, smokes 10 cigarettes daily
On examination
RR: 14 Heart sounds normal
Pulse 88 Chest Clear
Sats: 100% on air Abdomen: soft but generalised tenderness
BP 100/58
Temp: 38.3
Plan: IV fluids
Admit Medics
Paracetamol
?may need side room
Imagine that you are one of the junior doctors working on AMU and you are asked to go and see this patient.
1. What person protection methods will you employ when you go to see this patient?
2. In addition to the information from the clerking what other questions would you like to ask in your history to establish the likely cause of his symptoms?
On further questioning it is apparent that the patient recently had a course of amoxicillin for a community acquired pneumonia infection. As far as he knows he has not been in contact with anyone else with diarrhoea or vomiting. He and his wife eat the same food and she has not developed any symptoms. He has not been abroad in 8 years.
3. Using the clerking notes and the additional history above please complete the ‘D&V Patient Assessment Emergency Department &AMU’ Pathway. What advice is recommended for this patient?
4. Having clerked this patient what investigations would you like to request to aid your assessment of his condition? For each explain what you are looking for.
5. Stool investigations come back positive for Clostridium difficile. What type of bacteria is C difficile?
6. Clostridium difficile is a minor component of the normal flora of the large intestine. What elements of the Innate Immune system normally prevent an infection occurring with regard to bacteria in the large bowel?
Use the information gained from the lecture last week on the Innate Immune system. Try to remember the headings that were used (or look up the lecture)
7. Use of some antibiotics is linked to increase susceptibility to clostridium difficile infections. What is the mechanism behind this?
8. Apart from amoxicillin what other antibiotics are frequently associated with a Clostridium difficile infection?
9. Clostridium difficile exerts its pathological effects by producing toxins. What are these toxins and how do they work?
10. Clostridium difficile is part of a group of clostridium bacteria. Can you name the other bacteria in this group and diseases that they might cause?
11. Self-Study: Something to consider
In an earlier question you outlined the role of the Innate Immune system in the GI tract. In a subsequent lecture you will learn about the ‘Adaptive Immune System’ which is also very active in the GI tract and has some specialised functions. In last week’s session on acute sepsis we discussed that a large part of the problem with acute sepsis is the over-reaction of the immune system and damage to body systems. QUESTION: Since the GI tract is so full of micro-organisms and since there is a frequent exposure to ingested pathogen why is there not a constant state of immune reaction with inflammation in the bowel? You will need the knowledge of the adaptive immune system and some extra reading to answer this. But it illustrates the remarkable nature of the immune system.