Infectious Disease

Question 1

What is HIV and when was it first recognised?

Answer 1

Human immunodeficiency virus

1984

Question 2

When has treatment for HIV been available since?

Answer 2

1996

Question 3

How many people are living with HIV now worldwide?

Answer 3

37 million people

Question 4

How many people are living with HIV in the UK now? How many are undiagnosed?

Answer 4

100 000

18000 undiagnosed

Question 5

How many new diagnoses of HIV are made each year in the uk?

Answer 5

6000 a year, mainly 20-39 year olds

Question 6

What is the mortality of HIV if diagnosed late when CD4 count is less than 100?

Answer 6

8% at 1 year

Question 7

What is the mortality rate of HIV when diagnosed early, when CD4 count is more than 200?

Answer 7

0.5% mortality at 1 year

Question 8

What is normal CD4+ T cell levels and what is it when opportunistic infections arise?

Answer 8

500+ normal

Question 9

When should you be tested again for HIV if risk of exposure?

Answer 9

Test when exposed and 3 months after

Question 10

Who should be routinely tested for HIV?

Answer 10

Men who have sex with men
IV drug users
Pregnant women
Anyone with another STI/partner has STI
From a country of high prevalence or partner from that country

Question 11

Indicators for HIV testing?

Answer 11

Any opportunistic infection
Pneumonia
Blood disorders
Weight loss
Shingles
Lymphadenopathy

Question 12

Name the 5 most common opportunistic infections

Answer 12

Seroconversion illness 
Pneumocystis jirroveci pneumonia (PCP)
Toxoplasmosis gondii
Kaposi's sarcoma
Tuberculosis

Question 13

What is seroconversion illness also called?

Answer 13

Acute HIV syndrome
Similar to glandular fever
Can drop CD4+ counts low enough to get infections

Question 14

What is the commonest opportunistic infection in the UK?

Answer 14

Pneumocystis Jirroveci pneumonia

Question 15

Signs and symptoms of PCP pneumonia? Treatment?

Answer 15

Subacute insidious onset of breathlessness, fever, cough
Progressive hypoxia
Treatment= co-trimoxazole +/- steroids

Question 16

Toxoplasmosis gondii

Answer 16

Protozoan parasite
May be latent and reactivated when immunocompromised
Space occupying lesion in brain
Treated with sulfadiazine and pyrimethamine

Question 17

Kaposi’s sarcoma

Answer 17

AIDS associated cancer
Vascular tumour of spindle cells -> dark red pigmented lesions
Skin and viscera
Driven by co-infection with HHV-8

Question 18

What is the most common complication of HIV worldwide?

Answer 18

TB

Question 19

Who should be giver ART?

Answer 19

All people with HIV at any CD4+ count

-> prevents onward transmission, extends life and improve health

Question 20

What is PrEP and who should be on it?

Answer 20

Pre-exposure prophylaxis
Anyone at substantial risk of HIV
(serodiscordant couples, sex workers, injecting drug users, men who have sex with men/transgender women, transgender people, prisoners)

Question 21

What is a community acquired infection?

Answer 21

An infection contracted outside of a healthcare setting, or present

Question 22

Why is it important to know if an infection is community or hospital acquired?

Answer 22

Different organisms and resistance patterns

Community cases are a potential marker for developing outbreaks

Question 23

What is the most common community and hospital acquired cause for pneumonia?

Answer 23

Comm: Strep pneumonia
Hosp: Gram -ve E.coli/Klebsiella

Question 24

What is the most common community and hospital acquired cause for meningitis?

Answer 24

Comm: Strep pneumonia
Hosp: Gram -ve E.Coli/Klebsiella

Question 25

What is the most common community and hospital acquired cause for UTI?

Answer 25

Comm: E.coli Hosp: E. coli

Question 26

What are the main infective organisms for hospital acquired infections?

Answer 26

Gram -ve E.coli and Klebsiella Pseudomonas Staph aureus

Question 27

What are the 2 main infective organisms for community acquired infections?

Answer 27

Strep pneumoniae | Haemophilus influenzae

Question 28

Signs and symptoms of meningitis

Answer 28

``` Headache, neck stiffness, photophobia CSF raised WCC and raised protein Meningeal enhancement on CT Sepsis? Rash (in neisseria meningitis) ```

Question 29

What is the most common cause of meningitis in the young versus old

Answer 29

Viral in young | meningococcal if older

Question 30

Why is travel history useful in meningitis presentation?

Answer 30

Tick borne encephalitis West nile virus Lyme's disease

Question 31

Treatment of meningitis?

Answer 31

``` Stabilise airway, breathing, circulation Intensive care? Senior review? GCS documented Blood cultures and nasopharyngeal swab LP if not shock or sever sepsis Start treatment (antibiotics) Fluid resus if septic ```

Question 32

If CSF us cloudy/purulent, what is likely?

Answer 32

Bacterial meningitis

Question 33

If CSF is viscous and clear/opaque what is likely?

Answer 33

TB meningitis

Question 34

If CSF is clear, what is likely?

Answer 34

Viral meningitis

Question 35

If CSF >90% neutrophils present and low protein, what is likely?

Answer 35

Bacterial meningitis

Question 36

If CSF has few neutrophils plus low protein what is likely?

Answer 36

Viral meningitis

Question 37

if CSF has high protein and low glucose, what is likely?

Answer 37

TB meningitis

Question 38

What antibiotics usually treat bacterial meningitis?

Answer 38

Ceftriaxone/Cefoxione IV

Question 39

If meningitis is penicillin resistant pneumococci?

Answer 39

Add vancomycin IV

Question 40

Complication of meningitis infection?

Answer 40

Subdural empyema Seizures Hydrocephalus Central venous sinus thrombosis