Microbiology

Question 1

What is conjunctivitis?

Answer 1

Inflammation of the conjunctiva could be due to infection, trauma or allergy

Question 2

What is more common, bacterial or viral conjunctivitis?

Answer 2

Viral

Question 3

Signs and symptoms of conjunctivitis?

Answer 3

Sore, red eye/s often with discharge

Purulent discharge if bacterial

Question 4

Bacteria often involved in bacterial conjunctivitis?

Answer 4

Staph A, Strep pneumonia and haemophilus influenza

Question 5

Bacteria often involved in neonatal conjunctivitis?

Answer 5

Staph A, Neisseria, gonorrhoea and chlamydia

Question 6

Who with bacterial conjunctivitis needs referred to ophthalmology?

Answer 6

Neonates

Question 7

Signs and symptoms of chlamydial conjunctivitis?

Answer 7

Often slow onset with discomfort over weeks 
Scanty non purulent discharge 
Follicular reaction (multiple slightly elevated lesions with the appearance of rice grains)

Question 8

Which type of conjunctivitis can cause follicular reactions like rice grains?

Answer 8

Chlamydial

Question 9

3 viruses that may be involved in conjunctivitis? What are the characteristics of each?

Answer 9

Adenovirus, herpes simplex and herpes zoster
Adeno: after a cold, red eye
HSV: Lymph nodes and cutaneous lesions
Zoster: Can effect skin and eye along different CN5 divisions

Question 10

Treatment of viral conjunctivitis?

Answer 10

Self care measures

Should resolve

Question 11

Treatment of herpetic conjunctivitis?

Answer 11

Aciclovir

Need to reduce risk of corneal involvement in HSV and post herpetic neuralgia in zoster

Question 12

Treatment of bacterial conjunctivitis?

Answer 12

May resolve on own if serious or need quick resolution give chloramphenicol

Question 13

Treatment of chlamydial conjunctivitis?

Answer 13

Topical erythromycin or oxytetracycline

Question 14

Describe different preparations of chloramphenicol?

Answer 14

Drops must be stored in fridge

Ointment has preservative so doesn’t need fridge but can’t see well after putting it on

Question 15

What is keratitis?

Answer 15

Corneal inflammation which can be caused by infection

Question 16

What are symptoms of keratitis?

Answer 16

Sensation of foreign body or pain, photophobia and lacrimation

Question 17

Dendritic ulcer =

Answer 17

Herpes simplex keratitis

Question 18

Is keratitis treated in the community?

Answer 18

No
Must be referred to hospital due to risk of scarring
Hourly eye drops!

Question 19

Why must you not use steroids if red eye in community?

Answer 19

Cant rule out herpes simplex keratitis and if use steroids in this you can worsen and risk perforation of the cornea

Question 20

Treatment of herpes simplex keratitis?

Answer 20

Ganciclovir or Aciclovir hourly eye drops

Question 21

2 organisms involved in contact lens associated keratitis?

Answer 21

Acanthomoeba or pseudomas due to water contact

Question 22

Acanthomoeba keratitis is often diagnosed late and extremely painful what is treatment?

Answer 22

Hourly eye drops (potentially with chlorohexidine)

Question 23

Pseudomonas keratitis is treated with?

Answer 23

Hourly oflaxacin drops

Question 24

Signs and symptoms of orbital cellulitis?

Answer 24

Swelling
Painful
Proptotis 
Often associated with paranasal sinusitis 
Pyrexia

Question 25

Treatment of orbital cellulitis?

Answer 25

Sight threatening- urgent! | Treat with ENT and broad spectrum antibiotics

Question 26

Organisms in orbital cellulitis?

Answer 26

Staph A, Strep pneumonia and HIB | ones in URTI/ sinusitis as often spread from here

Question 27

What is endophthalmitis?

Answer 27

Rare infection of the whole globe which is almost always post surgical

Question 28

What type of infection is almost always post surgical?

Answer 28

Endophthalmitis

Question 29

Symptoms of endophthalmitis?

Answer 29

Usually after a surgery Very red eye Very systemically unwell Significantly reduced vision

Question 30

Treatment of endophthalmitis?

Answer 30

Intravitreal sample then antibiotics Systemic antibiotics are probably of little value Amikacin, ceftazidime, vancomycin

Question 31

What is chorioretinitis?

Answer 31

Inflammation of the choroid (pigmented vascular coat) and retina - a form of posterior uveitis

Question 32

Causes of chorioretinitis?

Answer 32

Often congenital cause by toxoplasma or CMV, may also be associated with autoimmune disease. Can be caused by toxocara, CMV can effect those with HIV/ AIDS

Question 33

Presentation of chorioretinitis?

Answer 33

Painless rapid blurring of vision

Question 34

How does toxoplasma enter the bloodstream?

Answer 34

Through ingested, infected material or via maternal placenta

Question 35

Describe toxoplasma and chorioretinitis

Answer 35

Often people are unaware they are infected and have the chorioretinitis, can lie latent for years, if active the chorioretinitis usually subsides over many weeks and only requires treatment if the chorioretinitis is sight threatening (close of adjacent to the macula or optic disc) It is treated with clindamycin/ azithromycin sometimes steroids

Question 36

Describe toxocara and chorioretinitis?

Answer 36

Parasitic nemotode (round worm) Often self limiting as they cannot replicate In immunosuppressed can form granulomas which can cause irreversible visual loss

Question 37

Describe how may determine the difference between orbital cellulitis and pre-septal cellulitis?

Answer 37

If orbital patient will have proptosis and painful eye movements.

Question 38

Symptoms of blepharitis? What is it? Treatment?

Answer 38

``` Inflammation of the eyelids sore eyelids itchy eyes a gritty feeling in the eyes flakes or crusts around the roots of the eyelashes red eyes or eyelids eyelids sticking together in the morning when you wake up SYMPTOMS OFTEN COME AND GO Conservative, clean eye lids, hot packs ```