Infections of the Sensory System Flashcards
what is innate immunity
non-specific diseases
1st line
skin
mucous membranes
secretions
2nd line
phagocytic leukocytes
antimicrobial proteins
inflammatory response
fever
what is adaptive immunity
third line
lymphocytes
antibodies
memory cells
what are ocular defence mechanisms
innate
-eyelids- sweep away dirt, small microbes
-tears, mucin
-ocular epithelium
-ocular bacterial flora
-antibacterial factors
-macrophages and NK cells
-BONY ORBIT
oil later
water layer
mucin layer
corneal epithelium-non keratanised with goblet cells for lubrication of eye
adaptive defence
-eye associated lymphoid tissue
-langerhan’s cells
-immunoglobins
-t lymphocytes
-b-lymphocytes
what makes up the bony orbit
frontal, sphenoid, maxillary, zygomatic, palatine, ethmoid, and lacrimal
what are langerhan’s cells
sub-population of dendritic cells
catch and report to t and b lymphocytes
sit on cornea and in transplant causes rejection
what is a blow out fracture
-high pressure in sinus and blow nose
-trauma
fractured maxillary bone
eyeball fall into maxillary sinus
stress and damage on optic nerve and extraocular eye muscles
lets infection from sinus into orbit
discuss role of lysozome and lactoferrin
enzymes found in tears
lysozyme cleaves PEPTIDOGLYCANS (found in bacteria walls)– good with gram positive who has it in their outer wall
lactoferrin binds IRON- STARVES bacteria and fungi blocks viral lipoprotein bonds
-alters the permeability of the lipopolysaccaride later giving access for lysozyme
what is found in the ocular biome
staphylococcus
streptococcus
propionbacterium
corynebacterium
collection of commensals
keep immune system prime
competitively inhibit growth of pathogenic organisms
-takes up all resources
what pathogens are found in common viral conjunctivits
coronaviruses
rhinoviruese
respiratory syncytial virus
parainfluenza
what are the different kinds of conjunctivitus
common viral
adenovirus related
common bacterial
neonatal
symptoms of common viral conjunctivits
how to help
sticky
watery
pink
discomfort
slef limiting
rarely cause seious damage
1 eye until spreads
cold compress
artificial tears
sterile water
paracetamol
step in if longer than a week
what are symptoms of adenovirus conjuctivits
bilateral
very sticky
red
painful
6-8 weeks
visual blurring– PUNCTUATE KERATITIS
sore throat and cough
same as common viral conjunct for treatment
what are the symptoms for bacterial conjunctivitis
what treatments
discharge more yellow than viral
go away with ANTIBIOTICS
-CHLORAMPHENICOL
-FUSIDIC ACID
what can cause bacterial conjunctivitis
haemophilus influezae
streptococcus pneumoniae
moraxella
if discharge very xs– may be ghonnorea
what causes neonatal conjunctivits
may be normal bacterial/viral/sti from birth canal
0 days
neisseria gonorrhoeae
5 days
chlamydia trachomatis
5 weeks
haemophilus influenza
streptococcus
what is keratitis
what can cause it
corneal abrasion
inflammation of cornea
bacterial- staph. aureus, strept. pne, pseudomonas species
viral- HSV, HZO
fungi
what happens in keratitis
inflammation seeps through into different corneal layers
causes noxious response which dissolves cornea epithelium and stroma
–ulceration and scarring
what is hypopynum
an accumulation of leukocytes in the anterior chamber due to severe intraocular inflammation
how is the cornea weakened
more issues if dry-> keratoconjunctivitis sicca DRY EYE DISEASE
tear film deficiencies
eyelid malformation- exposure of cornea
endogenous cause-mechanical abrasion
exogenous cause- TRAUMA (foreign bodies, cat scratches)
if can’t close eye eg. after stroke
how do HSV keratitis occur
what are the symptoms
how do you treat
usually direct contact
(like from cold sore)
UNILATERAL
painful
red
watery
photophobic
topical and oral ACICLOVIR
what are the different types of ulcer found in HSV keratitis
dendritic ulcer
geographic ulcer
these cause new vessels, loss of sensation, scarring
what is the leading infectious cause of blinding
trachoma
how does trachoma come about
what is the infective cause
between close contact from lack of hygiene, sanitisation
flies
eyelids turn in– trachomatous trichiasis
–scarring
which causes permanent blindness
(fixed with corrective surgery)
CHLAMYDIA TRACHOMATIS
what is trachomatis trichiasis
in turned lash that rubs the cornea
causes recurrent inflammation in conjunctiva
what is trachoma eradication trying to do
to clear trachoma from endemic populations
Surgery
Antibiotics
Facial cleanliness
Environmental change
what is ONCHOCERCIASIS
river blindness
2nd leading causing of infection blindness
CENTRAL AFRICA
parasitic disease
onchocerca larvae carried by black flies
worm bites
birth larvae
which spreads to different tissues like eye and die which causes inflammation
what is the treatment for river blindness
IVERMECTIN
-yearly for 10-15 years
clear from population
what is orbital cellulitis
signs
how it presents
ophthalmological med emergency
2 types- pre and post septal cellulitis
post is more dangerous:
spread of infection into deeper structures
orbital abscess (push eyeball out)
meningitis
cavernous sinus thrombosis
optic nerve damage
bacteremia/sepsis
pre (just area around eye)
signs?
swelling
red
pain
proptosis
RAPD
tenderness
photophobia
what infections cause orbital cellulitis
haem. influenza
staph. a
strept. pn
neta-haemolytic streptococci
what is toxoplasmosis retinochoroidits
what species causes it
infectious condition
retinochoroidal lesions
postior uveitis
FOG IN HEADLIGHT SIGN WITH ADJACENT PIGMENTENTED RETINAL CHOROIDAL SCARRING
toxoplasmosis gondii (cat litter)
-spontaneous miscarriage
-blindness
-enchephalitis
what is the treatment for toxoplasmosis
oral pyrimethamine
sulfadiazine
corticosteroids
what are some ocular manifestations of patients with HIV/AIDS
retinochoroiditis toxoplasma
endophthalmitis
HIV reproduces in CD4+ t cells
can tell what they might be susceptible by their cell count
250/uL- toxoplasmosis
100/uL- CMV
what is cytomegalovirus retinitis CMV
what is treatment
cotton wool on retina
antiviral ganciclovir
what is endophthalmitis
treatment
develops after intra-ocular operation
trauma with inoculation of foreign body
complication of systemic infection
intra-ocular and systemic antibiotics
virectomy
what is otitis externa
epithelium of the ear can be affected by comon skin conditions
eg. eczema, psoriasis
pain
ear ache
itch
discharge
swimmers ear- gets moist for bacteria to grow in
cottage cheese discharge, can be blood stained
conduction deafness
ear drops
what is innate immune system for upper resp. tract
hair follicles
ciliated cells
what are common microorganisms for otitis externa
pseudomonas aeeruginosa
staph aure.
less common
candida albicans
aspergillus niger
what is otitis media
what are pathogen
middle ear
most common in infants and small children- flatter eustachian tubes
50% viral in origin
mainly RSV
also s. pneu, and h. inflenzae
young:
red ears, fever, crying, poor feeding, restlessness, hearing difficulties, delayed learning development
glue ear- fluid in middle ear
bulging ear drum and dilated vessels
chronic suppurative otitis media
what is mastoiditis
a severe complication of otitis media
spread of infection from middle ear to mastoid air cells via the mastoid antrum
mastoid process inflammation
redness
tenderness
pain behind the ear
pushed forward pinna
fever
fatigue
if unwell
IV antibiotics
what is sinusitis
pathogen invasion of the air spaces associated with URT
mucosal swelling prevents muco-ciliary clearance of infection
exacerbated by local accumulation of inflammatory bacterial products
nasal blockage
discharge with facial pain/pressure/loss of smell
self limiting
increase in symptoms after day 5 of urt infection -double sickening
what are causative agents of comomon cold and symptoms
40%rhino
30% coronaviruses
coxsackie virus a
echovirus
parainfluenza virus
tired, pyrexia, malaise, sore nose, pharynx. nasal discharge, sneezing
what is pharyngitis
when should you worry
Pharyngitis is often is associated with
pharyngeal exudate and cervical
lymphadenopathy
* Sore throat, reduced oral/fluid intake,
fatigue, lethargy, fever, Headache,
nausea, vomiting.
* Management: Self-limiting for most,
antibiotics need to be considered for
some.
worry if taking DMARDS, carbimazole, HIV, chemo
what causes pharyngitis
Viruses
* Cytomegalovirus (CMV)
* Epstein-Barr virus (EBV)
* Herpes simplex virus type I (HSV-1)
* Rhinovirus
* Coronavirus
* Adenovirus
* Bacteria
* Streptococcus pyogenes
* Haemophilus influenzae
* Corynebacterium diphtheriae
discuss CMV
Cytomegalovirus (CMV)
* Transmission in body secretions and organ transplants
* Usually asymptomatic or mild in healthy adults
* CMV causes cold-like symptoms, such as a
sore throat, fever, fatigue and swollen glands.
* Symptoms last for only a few short weeks and is
not worrying for healthy children or adults.
* Virus can reactivate and cause disease when cellmediated immunity is compromised
* Treatment with ganciclovir, foscarnet, cidofovir
what is tonsilitis
Inflammation of the tonsils
– typically palatine. Can be viral or bacterial.
Therefore
– may or may not need antibiotics.
* Symptoms: Dysphagia, odynophagia, cervical lymphadenopathy, fever * 90% of cases will resolve in 7 days without treatment
what is fever pain scoring
- A score of 0-1 is associated with 13-18%
isolation of streptococcus (close to
background carriage rates). - No antibiotics recommended.
- A score of 2 is associated with 30-35%
isolation of streptococcus. - Delayed antibiotic may be
appropriate. - A score of 3 is associated with 39-48%
isolation of streptococcus. - Delayed antibiotic may be
appropriate. - A score of 4 or more is associated with 62-
65% isolation of streptococcus. - Consider antibiotics if symptoms
are severe or a short delayed
prescribing strategy may be
appropriate (48 hours).
what are some complications of streptococcus pyogenes
complications * Scarlet Fever * Caused by
erythrogenic toxin
from S. pyogenes
* Peritonsillar abscess
(“quinsy”)
* Otitis media / sinusitis * Rheumatic heart
disease
* Glomerulonephritis
acute Group A streptococcal (GAS): * 5 to 15 years old * more common in the winter * High Fever PAIN or CENTOR score * A scarlatiniform rash may be
present, especially in children. * Significant complications if not
treated
Treatment: * Able to swallow Benzylpenicillin IV * Unable to swallow Penicillin V * Paracetamol, Ibuprofen, IV Fluids
what is quinsy
- Collection of pus between the tonsillar capsule and superior
constrictor muscle. - Complication of untreated bacterial pharyngitis / tonsillitis
- Symptoms: Fever, pain, trismus, general malaise
- Signs: Hot-potato voice, unilateral swelling, deviation of uvula
- Management: Same day hospital admission to ENT.
- Needle aspiration / drainage, IV antibiotics (Penicillin based) and IV
Steroids, analgesia and IV Fluids until oral route available. - Complications: Retropharyngeal or deep neck space infection in
fascial planes of the neck,
HOT POTATO VOICE
what is glandular fever
Replicates in B lymphocytes
* Clinical features:
* Fever
* Headache
* Malaise
* Sore throat
* Anorexia
* Palatal petechiae
* Cervical lymphadenopathy
* Splenomegaly
* Mild hepatitis
Diagnosis: EBV Serology, FBC and LFTs
EBV IgM – Acute 4-6 weeks
EBV IgG – Lifelong (Indicative of past infection)
what is the mumps virus
parotitis
Clinical features:
* Fever, Malaise, Headache
* Anorexia, Trismus, joint pain
* Severe pain and swelling of
parotid gland(s)
* Treatment is supportive /
symptomatic
* 88% resistance with full
vaccination
what is acute epiglottitis
HAEMOPHILUS INFLUENZA
- Present in nasopharynx of 75% healthy people
- 88% reduction in cases since vaccine in 1992
- Clinical features:
- High fever / Bacteraemia
- Massive oedema of the epiglottis - tripod position
- Severe airflow obstruction – Stridor, Dysponoea
Most often seen in young children 2 to 6 years of age
MEDICAL EMERGENCY needing 999 ambulance to hospital
for intubation and IV antibiotics. Do Not examine a child with
suspected epiglottitis without an anaesthetist.
what is diagnosis and treatment for diptheria
diagnosis: * Made on clinical grounds as therapy is
usually urgently required
* Treatment: * Prompt anti
-toxin therapy administered
intramuscularly
* Concurrent antibiotics (penicillin or
erythromycin)
* Strict isolation and contact tracing
