Malaria

Question 1

Plasmodium Falciparum

Answer 1

-Most common
-Responsible for severe disease and malaria-related deaths
-Incubation 7-14 days
Quotidian or irregular paroxysms

Question 2

Plasmodium Vivax

Answer 2

• Causes benign tertian malaria

- Relapse due to dormant parasites

Question 3

Plasmodium Ovale

Answer 3

-Relapsing course as with P. vivax

Question 4

Plasmodium Malariae

Answer 4

• Beningn quartan malaria
• Long incubation period
• Causes nephrotic syndrome in late stages

Question 5

Malaria Pathogenesis

Answer 5

• Sporozoites travel via bloodstream to liver where they mature
• Mature organisms then rupture to release further organisms (merozoites) into the blood where they invade RBCs and undergo asexual reproduction
• Feeding mosquitos ingest theses and in mosquito gut they undergo sexual reproduction to produce thousands of sporozoites

Question 6

Malaria Presentation

Answer 6

• No specific symptoms
• Fever, chills, rigors, headache, cough, splenomegaly, hepatomegaly
• In severe disease (usually falciparum), impaired consciousness, SOB, bleeding, fits, nephrotic syndrome
• Symptoms may occur from six days of naturally acquired infection to many months later
• Most patients with P. falciparum infection present in first month or within first six months
• vivax and ovale present later than 6 months, sometimes after years

Question 7

Malaria Differentials

Answer 7

• Typhoid
• Hepatitis
• Dengue fever
• Influenza
• HIV
• Meningitis/encephalitis

Question 8

Malaria Investigations

Answer 8

• Thick and thin blood smears with Giemsa stain are ‘gold standard’
• When negative get two further blood samples
• FBC (thrombocytopenia and anaemia)
• G6PD before starting some treatments
• LFTs
• U&Es show lowered sodium and creatinin

Question 9

Malaria Management Non-Falciparum

Answer 9

-Admit if falciparum or severe or unsure

Non-falciparum

• Manage on an outpatient basis unless comorbid
• Chloroquine
• Where chloroquine fails quinine, artemether and lumefantrine
• Primaquine to prevent relapse

Question 10

Malaria Management Falciparum

Answer 10

• Admit
• Oral quinine sulphate plus doxycycline
• Atovaquone-proguanile
• Artemether with lumefantrine
• If severe give quinine IV and doxycycline