Session 11 - Group Work Flashcards
- Why may a bacteriostatic agent be less effective in patients who are immunocompromised?
Bacteriostatic agent doesn’t kill bacteria, just stops them from dividing and gives it enough time so the body can kill it. However, if you’re severely immunocompromsied your body can’t kill it, so the infection won’t get worse but it also won’t get better.
- What prescribing consideration is important in ensuring that a bactericidal drug is able to effectively kill bacteria and not simply inhibit their growth?
You need to make sure the concentration you’re giving is high enough
- What effect may prescribing a bacteriostatic agent in conjunction with a bactericidal agent have on the ability for the bactericidal agent to work?
The bactericidal agent will be more effective in conjunction with the bacteriostatic agent because the bacteria is not still dividing - you’re fighting a set number.
- The major mechanisms that bacteria develop acquired resistance are spontaneous mutation, conjugation, transduction and transformation. Which of these mechanisms would be described as horizontal evolution?
Conjugation
Transduction
Transformation
1) A 55 year male presented to his GP with pleuritic chest pain and fever. He has a productive cough and is producing yellow sputum. He confirms to the GP that he is not asthmatic and smokes socially. During examination it is confirmed that the chest pain is increased on inspiration.
a) What likely diagnosis would you make?
Community-acquired pneumonia
Differentials could include:
Pleurisy
1) A 55 year male presented to his GP with pleuritic chest pain and fever. He has a productive cough and is producing yellow sputum. He confirms to the GP that he is not asthmatic and smokes socially. During examination it is confirmed that the chest pain is increased on inspiration.
b) What chest sounds would be expected during physical examination?
Generalised crackles
Bronchial breathing
Dull percussion
1) A 55 year male presented to his GP with pleuritic chest pain and fever. He has a productive cough and is producing yellow sputum. He confirms to the GP that he is not asthmatic and smokes socially. During examination it is confirmed that the chest pain is increased on inspiration.
c) What tests would you carry out to confirm your diagnosis?
Sputum culture
Full blood count
Chest x-ray
CRP
1) A 55 year male presented to his GP with pleuritic chest pain and fever. He has a productive cough and is producing yellow sputum. He confirms to the GP that he is not asthmatic and smokes socially. During examination it is confirmed that the chest pain is increased on inspiration.
d) What would your primary treatment recommendation be? If that was contraindicated what would you prescribe?
1st line = Amoxicillin PO 1g TDS for 5 days AND Doxycycline PO 200 mg OD for 5 days
(CAP CURB-65 score 2 (moderate))
Contraindication: Penicillin allergy = Doxycycline PO 200 mg OD for 5 days as a single therapy
(From Leicester Rx guidelines)
1) A 55 year male presented to his GP with pleuritic chest pain and fever. He has a productive cough and is producing yellow sputum. He confirms to the GP that he is not asthmatic and smokes socially. During examination it is confirmed that the chest pain is increased on inspiration.
e) Beyond being contraindicated, why may your second choice be preferable?
Dosing regimen is easier - 1/day tablet compared to several tablets/day.
1) A 55 year male presented to his GP with pleuritic chest pain and fever. He has a productive cough and is producing yellow sputum. He confirms to the GP that he is not asthmatic and smokes socially. During examination it is confirmed that the chest pain is increased on inspiration.
f) In patients whose infection is more severe and in other trusts, combination therapy is recommended. Which other class or antibacterial agent is recommended and what is its mechanism of action?
Co-amoxiclav if it is more severe (3 or over on the CURB-65 score) - this is a beta-lactam, which acts by inhibiting the synthesis of the peptidoglycan layer of bacterial cell walls.
Meropenem if the most severe (this is what you do realistically).
Review macroglides.
1) A 55 year male presented to his GP with pleuritic chest pain and fever. He has a productive cough and is producing yellow sputum. He confirms to the GP that he is not asthmatic and smokes socially. During examination it is confirmed that the chest pain is increased on inspiration.
g) What is the primary cause of resistance to β-lactam antibacterial agents?
Enzyme-mediated - Produces the enzyme Beta-Lactamase which breaks down the beta-lactam
2) A 68 year female type II diabetic has been visited by her GP at home after her care assistant became concerned about her left foot. Upon examination the doctor finds an ulcer with evidence that it is starting to affect the deep fascia. The area around the ulcer is warm and tender and erythematous. The lady reports that she is otherwise quite well and has no known allergies.
a) The patient is to be treated in her home. What initial therapy would you recommend? Detail the route of administration and your rationale.
Moderate infection (see Rx guidelines)
Flucloxacillin PO 1g qds and ciprofloxacin PO 500 mg bd and metronidazole PO 400 mg tds
PO because 1) guidelines 2) can take at home and does not require being in hospital.
2) A 68 year female type II diabetic has been visited by her GP at home after her care assistant became concerned about her left foot. Upon examination the doctor finds an ulcer with evidence that it is starting to affect the deep fascia. The area around the ulcer is warm and tender and erythematous. The lady reports that she is otherwise quite well and has no known allergies.
b) In addition to the initial prescription what would you also need to do on this visit in order to ratify or modify your treatment?
Take a sample from the abscess to check causative organism
If removal of the skin is required - which is often indicated to check the ulcer hasn’t extended any deeper - this can be used to send off the sample.
Also can draw an outline around the foot ulcer to check it’s not got any bigger
2) A 68 year female type II diabetic has been visited by her GP at home after her care assistant became concerned about her left foot. Upon examination the doctor finds an ulcer with evidence that it is starting to affect the deep fascia. The area around the ulcer is warm and tender and erythematous. The lady reports that she is otherwise quite well and has no known allergies.
c) Beyond the β-lactams, what class of antibiotics do the other agents you prescribed belong and what are their mechanisms of action.
Metronidazole is an azole - these inhibit nucleic acid synthesis
Ciprofloxacin - Quinolones inhibit DNA gyrase, these are very active against Gram negative bacteria or atypical pathogens
Flucloxacillin - penicillin, beta-lactase inhibitor
2) A 68 year female type II diabetic has been visited by her GP at home after her care assistant became concerned about her left foot. Upon examination the doctor finds an ulcer with evidence that it is starting to affect the deep fascia. The area around the ulcer is warm and tender and erythematous. The lady reports that she is otherwise quite well and has no known allergies.
d) What notable and common side effects would you warn the patient about in relation to the drugs you prescribed?
Nausea Diarrhoea Vomiting Eye disorders Ear disorders
