Microbiology Flashcards
what are some viral causes of oral ulceration?
herpes simplex virus (HSV)
herpangina
hand, foot and mouth disease
primary syphilis (bacteria)
which type of HSV causes oral lesions?
type 1
what is primary gingivostomatitis?
vesicles and ulcers on lips, buccal mucosa and hard palate
presentation of HSV
primary gingivostomatitis
fever
local lymphadenopathy
management of HSV
acyclovir
what is a cold sore?
HSV has established latency in a sensory nerve root and can be reactivated
diagnosis of HSV
swab to detect viral DNA by PCR
presentation of herpangina
vesicles/ ulcers on soft palate
cause of herpangina
coxsackie virus (enterovirus)
diagnosis of herpangina
swab
what causes hand, foot and mouth disease?
coxsackie virus
diagnosis of hand, foot and mouth disease
swab
presentation of primary syphilis
chancre is a painless indurated ulcer at the site of bacterial entry
what are apthous ulcers?
non-viral ulcers
presentation of apthous ulcers
painful with inflammatory halos
what conditions are recurrent ulcers associated with?
HSV
IBD, etc.
what is tonsilitis?
inflammation of the tonsils
causes of tonsilitis
bacterial
viral= coryza, influenza, strep
less common= HIV, gonococcal pharyngitis and diphtheria
non-infectious causes
non-infectious causes of tonsilitis
physical irritation e.g. GORD, tobacco, alcohol, hay-fever
cause of infectious mononucleosis?
EBV (herpes family)
presentation of infectious mononucleosis
sore throat lethargy 15-25 most common fever enlarged lymph nodes other= jaundice/hepatitis, rash, leucocytosis, splenomegaly and palatal petechiae
consider as differential in tonsillitis especially if lethargy persists.
when should infectious mononucleosis be suspected?
lethargy persists in second week
two criteria’s that are used for tonsilitis
CENTOR
FeverPAIN
describe the FeverPAIN criteria
fever purulence attend rapidly w3/7 inflamed tonsils no cough
when should phenoxymethylopenicillin be considered in tonsilitis?
score 4-5 on FeverPAIN
late complications of strep pyogenes
rheumatic fever
GM
presentation of rheumatic fever in strep pyogenes
3 weeks post sore throat with fever, arthritis and pancarditis
presentation of GM in strep pyogenes
1-3 weeks post sore throat with haematuria, albuminuria and oedema
presentation of diphtheria
sore throat
grey-white membrane across pharynx
exotoxin is cardio and neurotoxic
management of diptheria?
vaccine
complications of EBV
anaemia thrombocytopenia splenic rupture upper airway obstruction increased risk of lymphoma (immunosuppressed)
diagnosis of EBV
EBV IgM
Paul-Bunnel test or Monospot test for heterophile Ab
blood count and film
LFTs
management of EBV
bed rest
paracetamol
avoid sport
steroids in complicated cases
presentation of candida in the mouth
white patches on red and raw mucous membranes
causes of candida in the mouth
post-antibiotics
immunosuppressants
smoking
inhaled steroids
management of candida in the mouth
nystatin
fluconazole
how can a throat infection cause otitis media?
extension of infection up the eustachian tube
causes of otitis media
most viral with secondary bacterial (H. influenza, strep pneumonia and pyogenes)
management of otitis media
most resolve without antibiotics
how can otitis media lead to facial palsy?
facial nerve is exposed in the middle ear and can swell
how can otitis media cause mastoiditis?
otitis media > peri-tonsillar abscess (quinsy) > parapharyngeal abscess > mastoiditis
what is otitis externa?
inflammation of the outer ear canal
presentation of otitis externa
redness swelling itch pain discharge/ earwax potential for hearing loss
bacteria causes of otitis externa
staph aureus
proteus
pseudomonas aeruginosa
fungal causes of otitis externa
aspergillus
candida
what is malignant otitis externa?
extension of otitis externa into the bone surrounding the ear canal e.g. mastoid and temporal
risk if malignant otitis externa is not treated?
death due to risk of osteomyelitis of the skull
presentation of malignant otitis externa
pain and headache (more severe than clinical signs suggest)
granulation tissue at bone-cartilage junction
facial nerve palsy (drooping on side of lesion)
diagnosis of malignant otitis externa
CRP
imaging
biopsy
cultures
RF for malignant otitis externa
DM
radiotherapy of head and neck
presentation of acute sinusitis
discomfort over frontal and maxillary sinuses
URTIs
severe pain with purulent discharge if bacterial
management of acute sinusitis
antibiotics are only used in severe cases >10 days
1st line= phenoxymethylpenicillin
2nd line= doxycycline (NOT in children)
