Infection

Question 1

What is Ankylosing Spondylitis? Which HLA is it associated with?

Answer 1

Type of autoimmune disease.

Kind of arthritis involving long-term inflammation of the joints of the spine.

More than 90% of those with the condition have HLA-B27

Question 2

Which HLA is associated with Insulin-dependent Diabetes Mellitus?

Answer 2

50-75% of those with the condition have HLA DQ2

Question 3

What are the main types of malaria?
Which is most common?
What are the symptoms if severe?

Answer 3

Plasmodium falciparum, vivax and ovale.

Plasmodium falciparum is most common.

SYMPTOMS:
CVS - tachycardia, hypotension, arrythmias
CNS - Confusion, fits
Respiratory - ARDS
Blood - Low WCC, low platelets, DIC
GI - Diarrhoea, deranged LFTs, high bilirubin
Metabolic - hypoglycaemia
Renal - AKI

Question 4

What is the lifecycle of plasmodium falciparum?

Answer 4

1. Infected female Anopheles mosquito injects SPOROZITES
2. These migrate to liver and form MEROZOITES - released and invade RBCs
3. Here they become TROPHOZOITES
4. Multiply to form new MEROZOITES within RBCs - released when cell ruptures
5. Some become GAMETOCYTES and get picked up by female mosquito

Sexual cycle happens in mosquito to form new SPOROCYTES

Question 5

What is the treatment for Plasmodium falciparum?

And P. Vivas, ovale, malariae?

Answer 5

P. Falciparum - ARTESUNATE or QUININE + DOXYCYCLINE

P. Vivax, ovale, malariae - CHLOROQUINE + PRIMAQUINE, HYPNOZOITES in liver stage to prevent relapse due to dormant parasites

Question 6

Which organisms cause typhoid and paratyphoid (enteric fever)?
What antibiotics treat them?

Answer 6

Salmonella enterica serovar typhi/paratyphi A, B, C

CEFTRIAXONE or AZITHROMYCIN