ARULANANDAM TERENCE.T 403(A) Malaria ARULANANDAM TERENCE.T 403(A)

Topicality The worldwide annual incidence of malaria is between 300 and 500 million cases, causing between 1 and 2 million deaths. Areas with significant numbers of malaria cases include Africa, the Middle East, India, Southeast Asia, South America, Central America, and parts of the Caribbean.

Topicality Greater than 90% of severe, life-threatening malaria occurs in children.

Etiology Protozoal microorganism: Plasmodium falciparum Plasmodium vivax Plasmodium malariae Plasmodium ovale

Epidemiology Mosquito transmission is the most common route of infection

Epidemiology Transmission may result from intravenous drug abuse (shared needles) or blood transfusion. In these instances, only the erythrocytic cycle is established, because hepatocytes can be infected only by the sporozoite form of the parasite.

Life cycle Differences Plasmodium falciparum: All falciparum sporozoites that enter the liver remain active and develop into tissue schizonts that proceed to form thousands of merozoites P. falciparum merozoites can infect red blood cells of all ages

Life cycle Differences rapid asexual reproduction - rapid rise in the percentage of infected host red blood cells formation of red blood cell membrane knobs

Life cycle Differences P. vivax and P. ovale can form hypnozoites that can remain dormant within the liver for months P. vivax and P. ovale merozoites bind only young red blood cells, having the highest affinity for reticulocytes

Life cycle Differences P. malariae can persist as a low-level infection for up to 30 years P. malariae tends to infect older red blood cells

Clinical symptoms The incubation period is generally 9 to 40 days The hallmark of all forms of malaria is fever : initial “cold stage” , “hot stage” , “sweating” stage

Clinical symptoms Signs of anemia Splenomegaly and mild hepatomegaly Other symptoms associated with the fever (tachycardia, hypotension, cough, headache, back pain, nausea etc.)

Clinical symptoms Falciparum malaria: severe damage, particularly to the kidneys, brain, and lungs profound hemolysis jaundice blackwater fever renal failure CNS dysfunction up to coma pulmonary edema

Dignosis Thick smears – detection. Microscopic examination of a Giemsa-stained blood smear – identification. ELISA Immunoassay for species-specific parasite lactic dehydrogenase isoenzymes PCR

Diagnosis Hemolysis: Anemia Elevated levels of lactic dehydrogenase Increased reticulocytes Elevated unconjugated bilirubin level without a significant increase in hepatic enzymes (severe cases).

Diagnosis Severe cases of P. falciparum : Elevated serum creatinine Proteinuria Hemoglobinuria Hypoglycemia

Treatment oral chloroquine 600 mg base (1000 mg chloroquine phosphate), followed 6 hours later by 300 mg base (500 mg phosphate), repeated on days 2 and 3 Then for P. vivax or P. ovale oral primaquine 15.3 mg phosphate base (26.5 mg phosphate salt) daily for 14 days

Treatment Chloroquine-resistant P. falciparum: Hospitalization quinine 650 mg every 8 hours for 3–7 days plus doxycycline 100 mg twice daily for 7 days

Intravenous therapy Quinidine gluconate salt 10 mg/kg loading dose (maximum 600 mg) in normal saline should be infused slowly over 1 to 2 hours, followed by a continuous infusion of 0.02 mg/kg every minute until the patient is able to take oral medication

Treatment Levels of parasitemia above 5% require intensive treatment Levels of P. falciparum parasitemia above 10% to 15% - exchange transfusion Monitoring of: volume status, renal function, serum glucose, cardiac function Respirator support in cases of severe pulmonary edema

Chemoprophylaxis In chloroquine-susceptible areas – chloroquine 300 mg base orally per week In chloroquine-resistant areas - mefloquine 250 mg orally per week, or doxycycline 100 mg orally per day, or primaquine 0.5 ,mg/kg base per day