Microbiology

Question 1

An infection of the cornea is also know as?

Answer 1

Keratitis

Question 2

What are the common pathogens in neonatal bacterial conjunctivitis?

Answer 2

S.Aureus
N.Gonorrhoeae
Chlamydia Trachomatis

Question 3

What should be done with a case of neonatal bacterial conjunctivitis?

Answer 3

All should be referred onto ophthalmology

Question 4

What are the common pathogen in bacterial conjunctivitis?

Answer 4

S.aureus
Strep Pneumonia
H.Influenza - Children

Question 5

What is the treatment for bacterial conjunctivitis?

Answer 5

Swab + Topical Antibiotics

Question 6

What is the most used antibiotic in bacterial conjunctivitis?

Answer 6

Chloramphenical

Question 7

What other antibiotics can be used in bacterial conjunctivitis?

Answer 7

Gentamicin - Gram -ve and +ve

Fusidic Acid - Staph Aureus

Question 8

What are the common pathogens in viral conjunctivitis?

Answer 8

Adenovirus
Herpes Simplex
Herpes Zoster

Question 9

What is the clinical picture of someone with adenovirus conjunctivitis ?

Answer 9

Red irritated sclera, clear lense, no excess exudate

Question 10

What is the clinical picture of someone with herpes simplex conjunctivitis?

Answer 10

White pustules around the orbit
Red sclera
No excess exudate

Question 11

What is the clinical picture of someone with herpes zoster conjunctivitis ?

Answer 11

Punched out lesions in dermatomal pattern

Question 12

What is the disease history in someone with chlamydia conjunctivitis?

Answer 12

Often chronic and unresponsive to treatment.

Question 13

When should chlamydia conjunctivitis be suspected?

Answer 13

Bilateral conjunctivitis in a young adult

+/- urethritis or vaginitis

Question 14

What is important to get the patient too do once a diagnosis of chlamydia has been given?

Answer 14

Contact tracing

Question 15

What is the clinical picture of someone with chlamydia conjunctivitis?

Answer 15

Red irritated sclera
Excess exudate - gunk and tears
Follicles on the conjunctiva underside of the eyelid
Subtarsal scarring

Question 16

What is the treatment for chlamydia conjunctivitis?

Answer 16

Topical oxytetracyline

Oral azithromycin for the genital infection

Question 17

What method is used to diagnose and detect the disease causing pathogen in microbial keratitis?

Answer 17

Corneal scrapes

Question 18

What is the clinical picture in someone with bacterial keratosis?

Answer 18

White blood cell rich exudate within the anterior chamber look for fluid level within the cornea.
Red irritated sclera
Excess exudate

Question 19

What topical antibiotics can be used in bacterial keratosis?

Answer 19

Gentamicin + Cefuroxime

Gram +ve and -ve

Question 20

What should be done for someone with bacterial keratosis?

Answer 20

Admission for hourly drops and daily review

Question 21

What is bacterial keratosis linked to?

Answer 21

Contact lenses

Question 22

What is the clinical picture in someone with a herpes keratosis?

Answer 22

Very painful - look for ulceration
Irritated sclera
Lack of exudate

Question 23

What is the treatment plan for herpes keratosis?

Answer 23

Topical antiviral - acyclovir

NEVER use steroids as cause corneal perforation.

Question 24

Chronic herpes keratosis can cause what within the eye?

Answer 24

Loss of corneal sensation- won’t detect or respond t to damage being done to the eye.

Question 25

What is the clinical picture of someone with adenovirus keratosis?

Answer 25

Bilateral conjunctivitis Sub epithelial infiltrates within the anterior compartment. Red irritated sclera

Question 26

What usually precedes adenovirus keratosis?

Answer 26

An URTI

Question 27

What is the added risk of adenovirus keratosis?

Answer 27

It is infectious

Question 28

What is the treatment for someone with adenovirus keratosis?

Answer 28

Topical antiviral Topical antibiotic to prevent secondary infection Chronic infections - steroids can speed the healing

Question 29

What are the common organisms that cause fungal keratosis?

Answer 29

Pseudomonas Aeruginosa | Acanthamoeba

Question 30

What is the disease profile of someone with fungal keratosis?

Answer 30

Slow progression but also slow to heal | Linked to trauma from vegetation.

Question 31

What is the clinical picture of someone with orbital cellulitis?

Answer 31

Excruciating pain on movement of the eye Proptosis - out bulging go the eye and eyelid Fever Systemically unwell

Question 32

What is an orbital cellulitis linked to?

Answer 32

Paranasal sinusitis Post operative Focal Orbital infection

Question 33

What should be undertaken immediately once orbital cellulitis is suspected?

Answer 33

CT scan to determine whether the optic nerve, artery and vein have been occluded.

Question 34

What is the treatment for someone with orbital cellulitis?

Answer 34

Broad spectrum antibiotics + Monitor | Severe cases where sight is threatened drainage as a surgical intervention is an emergency.

Question 35

How is the causative organism identified in endophthalmitis?

Answer 35

Aqueous or vitreous culture.

Question 36

What is the clinical picture in someone with endophthalmitis?

Answer 36

``` Very painful Decreasing vision Really irritated and red sclera Massive exudate Yellow misty cornea ```

Question 37

What are the main causative organisms in endophthalmitis?

Answer 37

Staph epidermis | Conjunctival commensals

Question 38

What is the treatment for someone with endophthalmitis?

Answer 38

Intravitreal Amikacin / Ceftazidime / vancomycin | Topical antibiotics

Question 39

What is chorioretinitis?

Answer 39

Inflammation of the choroid and the retina

Question 40

If a patient with AIDS presents with chorioretinitis what is the most likely cause?

Answer 40

CMV - Cytomegalovirus

Question 41

On fundoscopy what does a CMV infection look like?

Answer 41

Fluffy white perivascular lesions Haemorrhage Granular retinal necrosis

Question 42

What is toxoplasma gondii associated with in chorioretinitis?

Answer 42

Raw meat and cats

Question 43

What is the clinical picture in someone with toxoplasma gondii chorioretintis?

Answer 43

Mild flu White focal retinitis +Vitreous inflammation Chronic - cysts

Question 44

What is toxocara Canis?

Answer 44

Roundworm

Question 45

What us toxocara Canis linked to?

Answer 45

Dogs and cats

Question 46

Why do toxocara Canis present a risk despite being self limiting?

Answer 46

They form granulomas

Question 47

How does chloramphenicol work?

Answer 47

Inhibits peptidyl transferase - stops protein synthesis

Question 48

Chloramphenicol is bactericidal to which organisms?

Answer 48

Streptococci | Haemophilus

Question 49

Chloramphenicol is bacterostatic to which organisms?

Answer 49

Staphylococci

Question 50

What antibiotics inhibit cell wall synthesis?

Answer 50

Penicillins Cephalosporins Both have a Beta lactic ring

Question 51

What antibiotics inhibit nucleic acid synthesis?

Answer 51

Quinilones e.g. Ofloxacin | Inhibit DNA gyrase so DNA unravels