Infections of the sensory system Flashcards
what defence mechanisms protect the eye
eyelids lacrimal system conjunctivae cornea blood-ocular barrier
what bacteria commonly cause conjunctivitis
haemophilus influenza
strep pneumonia
Moraxella spp
what bacteria commonly cause neonatal conjunctivitis
– Neisseria gonorrhoeae – Escherichia coli – Staphylococcus aureus – Haemophilus influenza – Chlamydia trachomatis
what bacteria commonly cause hca conjunctivitis
pseudomonas aeruginosa
what are the features of bacterial conjunctivitis
hyperaemic red conjunctivae
mucopurulent discharge
how can bacterial conjunctivitis be diagnosed
– Conjunctival swabs
– Corneal scrapings
– Culture & NAAT
what is the treatment for bacterial conjunctivitis
– Fusidic acid
– Tetracycline
– Chloramphenicol
what type of conjunctivitis does adenovirus cause
purulent conjunctivitis
enlargement of ipsilateral periauricular lymph node
corneal involvement
punctate keratitis
subepithelial inflammatory infiltration
where on the face does shingles (varicella zoster) normally infect
V1 dermatome
what are the features of V1 dermatome shingles
skin lesions on one side of the forehead
anterior uveitis
ocular perforation
retinal involvement
what can be used to treat shingles
aciclovir
topical steroids if severe
vaccine for prevention
what are the features of shingles
may be chronic (25%) very painful (post herpetic neuralgia)
what virus is the most common infectious cause of blindness in the developed world
herpes simplex
what are the features of herpes simplex infection of the eye
– Ulcerative blepharitis – Follicular conjunctivitis – Regional lymphadenopathy – Corneal involvement – not unusual -inflammation in deeper tissue -keratitis -corneal oedema -opacity
what is a dendritic ulcer
marker of HSV infection
seen on the eye when UV light is shone on
what is onchocerciasis
river blindness
onchocerca volvulus
black fly transmission
what regions is onchocerciasis found
W Africa, S America, C America
how can river blindness be treated
invermectin and doxycycline
what organism causes trachomatis (chronic keratoconjunctivitis)
chlamydia trachomatis
what are the features of trachomatis
lacrimation
mucopurulent discharge
conjunctival involvement
follicular hypertrophy
how is trachomatis treated
azithromycin
what is the plan for eradicating trachomatis by 2020
surgery for inturned eyelids
antibiotics
facial cleaning
environmental change
what are the ocular manifestations of AIDS
cotton wool spots
infarction of retinal nerve fibre layer
cytomegalovirus infection
how can cytomegalovirus be treated
ganciclovir
what causes endopthalmitis
ocular operation
trauma
inoculation of foreign body
systemic infection
what is endophalmitis
inflammation of the internal coats of the eye
can cause blindness
how can endophthalmitis be treated
vitrectomy and antibiotics
what are the host defences of the respiratory tract
saliva mucus cilia nasal secretions antimicrobial peptides
what are the common causes of cold
rhinoviruses
coronaviruses
coxsackie
what are the clinical features of cold
tiredness, pyrexia, malaise, sore throat
may have a secondary bacterial infection in minority
what causes acute pharyngitis and tonilitis
Epstein barr
cytomegalovirus
strep pyogenes
what are the features of cytomegalovirus infection
usually asymptomatic or mild
may reactivate during compromised immunity
how is cytomegalovirus treated
ganciclovir
foscarnet
where does EBV replicate (glandular fever)
B lymphocytes
saliva transmission
what age is EBV commonly contracted
1-6 yrs
14-20 yes
what are the features of EBV
fever headache malaise sore throat anorexia palatal petechiae (mini haemorrhages in the palate) lymphadenopathy splenomegaly mild hepatitis
what is the treatment for glandular fever
supportive
avoid sports/ heavy lifting
what are the complications of EBV
burkitt’s lymphoma
nasopharyngeal carcinoma
guillain barre
what causes tonsilitis
strep pyogenes
what are the features of tonsillitis
fever
pain
tonsilar enlargement
tonsilar lymphadenopathy
penicillin treatment
What causes scarlet fever
caused by erythrogenic toxin from S pyogenes
what causes a peritonsillar abscess
untreated tonsillitis
what are the complications of tonsillitis/ strep pyogenes
scarlet fever peritonisilar abscess otitis media sinusitis rheumatic heart disease glomerulonephritis
what is parotitis
caused by mumps virus
what are the features of parotitis
fever malaise headach anorexia trismus pain and swelling of the parotids
what is trismus
tightening of the jaw causing an inability to open the mouth
how is parotitis treated
mouth care
nutritional
analgesia
how is parotitis prevented
immunisation
MMR
what are the complications of parotitis
CNS involvement
epididymoorchitis
what causes diphtheria
corynebacterium diptheriae
what are the features of diphtheria
usually childhood disease
colonises pharynx, larynx and nose
aerosol transmission
sore throat
fever
lymphadenopathy
oedema of anterior cervical tissue (bull neck)
how is diphtheria diagnosed
anti toxin therapy
antibiotics
isolation
how can diphtheria be treated
immunisation
booster doses when travelling
what viruses can cause laryngitis and tracheitis
parainfluenza
RSV
Influenza
adeno
what are the features of laryngitis and tracheitis
hoarseness and retrosternal pain
stridor (croup)
what are the features of otitis and sinusitis
invasion of air spaces associated with URT
Middle ear, outer ear, sinuses
blockage of eustacian tubes
mucosal swelling
what causes otitis and sinusitis
RSV mumps, strep pneumonia haemophilis influenza bacteroids fragilis
who is otitis media most common in
infants and small children
what causes otitis media
RSV
s pneumonia
and H influenzae
what are the clinical features of otitis media
fever
diarrhoea and vomiting
bulging ear drum
glue ear (fluid in middle ear)
> chronic suppurative otitis media
hearing difficulties and delayed learning
how is otitis externa treated
antibiotic ear drops (polymyxin)
what are the features of acute sinusitis
facial pain
localised tenderness
how is acute sinusitis treated
ampicillin, amoxicillin, oral cephalosporins
