Malaria Turki M. Alanazi

Objective •Clinical picture of malaria.

•Complication of acute sever malaria.

Malaria

•Malaria is caused by Plasmodium parasites.

•P. falciparum is the most prevalent malaria parasite on the African continent. It is responsible for most malaria-related deaths globally.

•P. vivax,P.ovale & P.malariae are benign .. Rarely progress to severe malaria.

Clinical features • Initially ; flue like symptoms

headache, Fatigue. abdominal discomfort. muscle aches. Arthralgia. FEVER Splenomegaly. Mild jaundice.

Fever paroxysms • An abrupt onset of an initial ‘cold stage’ associated with a

dramatic rigor (paroxysm ) in which the patient visibly shakes.

• An ensuing ‘hot stage’ during which the patient may have a temperature >40°C, be restless and excitable, and vomit or convulse.

• Finally, the sweating stage, during which the patient's temperature returns to normal (defervesces) and sleep may ensue.

• Such a paroxysm can last 6-10 h.• A prolonged asymptomatic period may follow lasting ;• 38-42 h in the case of p.vivax and p.ovale

malaria (‘tertian’ fever) • 62-66 h in P. malariae infections (‘quartan’

fever).

• paroxysms associated with synchrony of merozoite release

• between paroxysms temper-ature is normal and patient feels well

• falciparum may not exhibit classic paroxysms (continuous fever)

Complication of Acute Sever Falciparum

Malaria

WHO criteria for sever falciparum malaria One or more of the following clinical or laboratory features

1 -Cerebral malaria (CM):

• ‘unrousable coma in the presence of peripheral parasitaemia where other causes of encephalopathy have been excluded'.

▫Febrile convulsion in children , hypoglycemia.•Most important complication of flaciparum

malaria.•Mortality rates of 20% among adults and

15%among children.•Focal deficits are uncommon •Retinal hemorrhages may be observed ;30 to 40

percent of cases.

2 -Hypoglycemia•  Hypoglycemia is a common complication of severe

malaria, although the usual signs (sweating, tachycardia, neurologic impairment) are difficult to distinguish from systemic symptoms due to severe malaria.

• Hypoglycemia occurs as a result of the following factors:

I. Diminished hepatic gluconeogenesisII. Depletion of liver glycogen storesIII. Increase in the consumption of glucose by the host

(and, to a much lesser extent, the parasite)IV. Quinine-induced hyperinsulinemia• Hypoglycemia is associated with a poor prognosis,

particularly in children and pregnant women.

3 -Acidosis  •Acidosis is an important cause of death from

severe malaria; it is caused by several factors, including:▫Anaerobic glycolysis in host tissues where

sequestered parasites interfere with microcirculatory flow

▫Parasite lactate production▫Hypovolemia▫Insufficient hepatic and renal lactate clearance

•The prognosis of severe acidosis is poor.

4 -Hematological abnormalities •Anemia in the setting of malaria occurs as

a result of the following factors: ( common in children )

Hemolysis of parasitized red cells Increased splenic sequestration and clearance

of erythrocytes with diminished deformability Cytokine suppression of hematopoiesis Shortened erythrocyte survival Repeated infections and ineffective

treatments•Disseminated intravascular coagulation

(DIC)

5-LIVER DYSFUNCTION•Mild hemolytic jaundice is common in malaria. •Severe jaundice is associated with P. falciparum

infections; is more common among adults than among children;

•Results from ▫hemolysis, ▫hepatocyte injury ▫cholestasis.

•When accompanied by other vital-organ dysfunction (often renal impairment), liver dysfunction carries a poor prognosis.

•6- NONCARDIOGENIC PULMONARY EDEM A;

Adults w ith severe falciparum malaria may develop noncardiogenic pulmonary edema even after several days of antimalarial therapy .

Pathogenesis unclear.

•7- RENAL IMPAIRM ENT Renal impairment is common among adults w

ith severe falciparum malaria but rare among children.

Pathogenesis unclear.

References