Malaria

Question 1

What is malaria?

Answer 1

Malaria is an infectious disease caused by protozoa of the Plasmodium family

Question 2

What are the species of Plasmodium known to cause malaria?

Answer 2

Plasmodium falciparum
Plasmodium vivax
Plasmodium ovale
Plasmodium malariae
Plasmodium knowlesi

Question 3

What is the pathophysiology of malaria?

Answer 3

Malaria is spread by mosquitoes - when a mosquito sucks up infected blood, parasites reproduce in the gut, producing sporozites (malaria spores)

The sporozites are injected into a person’s blood, where they travel to the liver.

The malaria parasites mature into merozoites, which enter the blood and infect red blood cells, causing rupture, and haemolytic anaemia

Question 4

How often does rupture and release of merozoites occur in malaria?

Answer 4

For P. vivax and P. ovale:
- Rupture and release of merozoites occurs every 48 hours

For P. falciparum:
- More frequent or irregular fever spikes

For P. malariae
- Spikes every 72 hours

Question 5

What is tertian malaria?

Answer 5

Malaria where the patient has a fever every other day (every 48 hours), due to rupture and release of merozoites every 48 hours

Question 6

What are the preventative measures that can be taken against malaria?

Answer 6

Avoiding outdoor activity after sunset
Insect repellants
Wearing long sleeved clothing and trousers
Insecticide-treated bed nets

Question 7

What medications can be used for malaria prophylaxis?

Answer 7

Chloroquine
Atovaquone/Proguanil
Doxycycline
Mefloquine

Question 8

What is the presentation of malaria?

Answer 8

Fever (up to 41 degrees)
Sweats and rigors
Myalgia
Headache
Nausea
Vomiting
Abdominal pain
Anorexia
Diarrhoea

Question 9

What are the signs of malaria on examination?

Answer 9

Pallor due to anaemia
Hepatosplenomegaly
Jaundice

Question 10

What investigation is diagnostic of malaria?

Answer 10

Malaria blood film
- Three negative samples over three consecutive days are needed to exclude malaria as a diagnosis

Question 11

What other investigations may be useful in the diagnosis of malaria?

Answer 11

Rapid diagnostic test (RDTs)
FBC - anaemia
Clotting screen - long PTT
U&Es
LFTs - unconjugated bilirubin

Question 12

What is the first line management of Plasmodium falciparum?

Answer 12

Oral chloroquine or hydroxychloroquine

Question 13

What is the second line management for Plasmodium falciparum?

Answer 13

If it is chloroquine resistant:
- Oral artemether/lumefantrine

Question 14

What is the first line management of severe Plasmodium falciparum?

Answer 14

IV artesunate

Question 15

What is the second line management of severe plasmodium falciparum?

Answer 15

IV artemether

Question 16

What is the management of non-falciparum species of malaria?

Answer 16

First line - oral chloroquine or hydroxychloroquine
Second line - oral primaquine

Question 17

What is the most common and severe cause of malaria?

Answer 17

Plasmodium falciparum

Question 18

What are the complications of P. falciparum malaria?

Answer 18

Cerebral malaria
Seizures
Reduced consciousness
AKI
Pulmonary oedema
DIC
Severe haemolytic anaemia
Multi-organ failure