microbio Flashcards
what are the two types of herpes simplex virus?
HSV-1
HSV-2
what is HSV-1 more associated with?
orofacial disease
what is HSV-2 more associated with?
genital disease
when is herpes simplex virus more commonly aquired?
in childhood
how is herpes simplex virus transmitted?
via infected oral secretions during close contact
what can cause primary gingivostamitis?
HSV-1
who is most ocmmonly affected by primary gingivostomatitis?
pre-school children
how does primary gingivostomatitis present?
- systemic upset (fever, malaise, headaches)
- painful oral ulcers
- local lymphadenopathy
what is treatment for primary gingivostomatitis?
- aciclovir treatment
- may take up to 3 weeks to recover
what is treatment for a cold sore?
aciclovir therapy
what is herpetic whitlow?
- HSV infection of the finger
- can occur by inoculation of the virus through a break in the skin
True/False
HSV-1 can cause encephalitis
True
what investigations are done to detect HSV-1?
swab of lesion and do a PCR
what is herpangina?
vesicles/ulcers on soft palate caused by enterovirus (especially Coxsackie virus)
what is herpangina?
vesicles/ulcers on soft palate caused by enterovirus (especially Coxsackie virus)
how is Herpangina diagnosed?
either clinically or by PCR
what causes hand, mouth and foot disease?
Coxsackie virus
how is hand, foot and mouth disease?
PCR or clinically
how does hand, foot and mouth present?
ulcers in hand, foot or mouth
can syphilis cause ulcers?
yes it can give you mouth ulcers
what are apthous ulcers?
non viral, self limiting, recurring painful ulcers of the mouth that are round or ovoid and have inflammatory halos
can apthous ulcers present outwith of the mouth?
no- are confined to the mouth
how long do apthous ulcers last?
usually <3 weeks
what is Behcets disease?
-a rare inflammatory disease of the blood vessels that causes recurrent oral ulcers, genital ulcers, uveitis, painful/swollen joints and headaches
what is acute pharyngitis?
inflammation of the part oft he throat behind the soft palate
most common causes of throat infections?
-viral or bacterial
what should be suspected if a sore throat is associated with lethargy into second week?
glandular fever
what are most common complications of pharingitis and tonsilitis?
- otitis media (most common)
- peritonsillar abscess
- parapharyngeal abscess
- lemierre syndrome
when to refer a patient with sore throat urgently?
- stridor
- breathing difficulty
- clinical dehydration
- systemically unwell
what is the most common bacterial cause of a sore throat?
Streptococcus pyogenes (group A strep/ Group A beta Haemolytic strep)
treatment for sore throat cause by streptococcus pyogenes ?
penicillin
what are complications of strep pyogenes?
- rheumatic fever (3 weeks post sore throat)
- glomerulonephritis (1-3 weeks post sore throat)
what scores/criteria have been made to try differentiate bacterial vs viral infections?
CENTOR criteria- increasing score increases likelihood of bacterial infection
Fever PAIN criteria- higher score increases likelihood of bacterial infection
what feverPAIN score would indicate prescribing antibiotics?
4 or more
what is diptheria?
- highly contagious infection caused by gram positive bacillus Corynebacterium diptheriae
- causes fever, sore throat, swollen glands, difficulty breathing or swallowing and a thick grey-white coating may cover back of throat, nose and tongue
what causes diptheria?
gram positive bacilli
corynebacterium diptheriae
what is treatment for diptheria?
- antitoxin and supportive
- penicillin/ eryhtomycin
There is also a vaccine!
what is infectious mononucleosis?
glandular fever
what causes infectious mononucleosis?
epstein barr virus
how does infectious mononucleosis present?
common:
- fever
- enlarged lymph nodes
- sore throat, tonsilitis, pharyngitis
- malaise
- lethargy
rare:
- jaundice/hepatitis
- leucocytosis
- splenomegaly
- palatal petechiae
how is infectious mononucleosis diagnosed?
labratory conformation
Epstein-Barr virus IgM
Heterophile antibody (Paul-Bunnell test, Monospot test)
Blood count and film
Liver function test
treatment for infectious mononucleosis?
- bed rest
- paracetamol
- avoid sport for 6 weeks
- corticosteroids may have a role in some complicated cases
how does candida/thrush present?
-white patches on red, raw mucous membranes in throat/mouth
what is the treatment for candida/thrush?
nystatin or fluclonazole
what is acute otitis media?
- an upper respiratory infection involving the middle ear by extension of the Eustachian tube
- more common in children as they have a shorter and more horizontal eustachian tube
how does acute otitis media present?
earache
what are most common bacteria that cause an ear infection? (otitis media)
- Haemophilius influenzae
- streptococcus pneumoniae
- streptococcus pyogenes
how are infections of the middle ear (otitis media) diagnosed?
swab of pus if eardrum perforates
what is the treatment for otitis media?
80% resolve in 4 days without antibiotics
First line- amoxicillin
second line- erythromycin
what is otitis externa?
-inflammation of the outer ear canal
how does otitis externa present?
- redness and swelling of the skin of the ear canal
- may be itchy
- can be sore and painful
- there may be discharge or increased amounts of ear wax
- if canal becomes blocked by swelling or secretions, hearing can be affected
what are common bacterial causes of otitis externa?
- staphylococcus aureus
- proteus spp
- pseudomonas aeruginosa
what are common causes of fungal otitis externa?
Aspergillus niger
Candida albicans
what is treatment of otitis externa?
- topical clotrimazole
- gentamicin 0.3% drops
what is malignant otitis?
- is an extension of otitis externa into the bone surrounding the ear canal
- without treatment is a fatal condition
- osteomyelitis will progressively involve the skull and meninges
what are symptoms of malignant otitis?
- pain and headache
- granulation tissue at bone-cartilage junction of ear canal
- exposed bone in ear canal
- facial nerve palsy
what are the investigations for malignant otitis?
- plasma viscosity/C reactive protein
- radiological imagin
- biopsy and culture to demonstrate the extent of the osteitis and its cause
what is treatment for acute sinusitis?
average length of illness is 2.5 weeks
- antibiotics for severe/deteriorating cases of >10 days duration
- 1st line= phenoxymethylpenicillin
- 2nd=doxycycline (NOT IN CHILDREN)
