Microbiology Flashcards
What is the basic diagnostic test for infection of the throat and pharynx?
Well-taken swab
The vast majority of throat infections are viral. True/False?
True
Thus don’t need antibiotics
What is the most common bacterial cause of sore throat?
Strep. pyogenes, causing acute follicular tonsillitis
What is the treatment for acute follicular tonsillitis?
Oral penicillin
Clarithromycin if pen-allergic
Describe Strep. pyogenes
Gram +ve cocci in chains
Beta-haemolysis (complete)
List some acute complications of Streptococcal sore throat
Otitis media
Peritonsillar abscess (quinsy)
Scarlet fever
List some late complications of Streptococcal sore throat
Rheumatic fever
Glomerulonephritis
Describe the clinical appearance of diphtheria
Severe sore throat
White membrane across pharynx
Exotoxin that is cardiotoxic and neurotoxic
There is a vaccine for diphtheria. What supportive treatment can be given?
Antitoxin
Penicillin/erythromycin
Describe the clinical appearance of oral thrush (Candida)
White patches on red mucous membranes in mouth
What is the treatment for oral thrush?
Nystatin suspension (topical)
What is otitis media?
URTI of middle ear caused by extension of infection through the Eustachian tube
List the main causes of otitis media
Usually viral
Secondary bacteria: H. influenzae, Strep. pneumoniae + pyogenes
What aids diagnosis of otitis media?
Swab of pus if eardrum perforates
Most otitis media resolves on its own. True/False?
True
Which antibiotics may be given for severe/bilateral acute otitis media?
Amoxicillin
Clarithromycin if pen-allergic
What is acute sinusitis?
Discomfort over frontal/maxillary sinuses due to viral congestion
If severe pain, tenderness and rhinorrhoea, consider secondary bacterial infection
If uncomplicated, avoid antibiotics in acute sinusitis. True/False?
True
Which antibiotics are indicated for acute sinusitis?
Penicillin
Doxycycline BUT NOT IN CHILDREN
Describe the clinical appearance of otitis externa
Red, swollen ear canal Itchy Painful Discharge/earwax Reduced hearing
List the main bacterial causes of otitis externa
Staph. aureus
Proteus spp.
Pseudomonas
List treatment of otitis externa
Topical aural toilet (cleaning)
Swab if unresponsive then treat according to culture
Clotrimazole for fungal
Gentamicin for Pseudomonas
What is another name for infectious mononucleosis?
Glandular fever - disease of young adults with some URT features
What is the classic triad of glandular fever?
Fever
Pharyngitis
Lymphadenopathy
List some complications of glandular fever
Splenic rupture
Upper airway obstruction
Thrombocytopenia
Lymphoma
What is the main cause of glandular fever?
EBV
What are the 2 phases of EBV infection?
Primary infection in children rarely progresses
Primary infection in those over 10yrs usually progresses
Outline treatment of glandular fever
Bed rest
Paracetemol
Avoid sport
Corticosteroid
Antivirals are not effective for glandular fever. True/False?
True
What lab tests are done for EBV?
IgM
Heterophile antibody - Paul-Bunnel, Monospot test
LFTs
Blood count
CMV infection may be similar to EBV - how to distinguish?
CMV has no heterophile antibodies