MALARIA

Question 1

Malaria species that predominates in Africa, New Guinea, and Hispaniola (i.e., the Dominican Republic and Haiti)

Answer 1

P. falciparum

Question 2

Malaria species that is more common in Central and South America and Southeast Asia

Answer 2

P.vivax

Question 3

Malaria species that is found in most endemic areas, especially throughout sub-Saharan Africa

Answer 3

P. malaria

Question 4

Processes central to the pathogenesis of falciparum malaria

Answer 4

cytoadherence, rosetting, and agglutination

Question 5

Genetic disorders that confer protection against death from falciparum malaria

Answer 5

RBC disorders such as thalassemias, sickle cell disease, hemoglobins C and E, hereditary ovalocytosis, glucose-6- phosphate dehydrogenase (G6PD) deficiency

Question 6

Clinical features indicating poor prognosis in severe Falciparium malaria

Answer 6

Marked agitation, Hyperventilation (respiratory distress), low core temp (<36.5), bleeding, deep coma, repeated convulsions, anuria, shock

Question 7

Hematologic findings in severe Falciparium malaria

Answer 7

Leukocytosis >12,000/uL, severe anemia, coagulopathy (low plt <50,000, prolonged PT and APTT, decreased fibrinogen)

Question 8

Manifestations of severe Falciparium malaria

Answer 8

unarousable coma/cerebral malaria, acidemia/acidosis (ph<7.2, HcO3<15), severe normocytic normochromic anemia (Hct<15, Hgb<50), renal failure (crea>265 mmol/L or >3mg/dL), non-cardiogenic pulmonary edema, hypoglycemia (CBG<40mgdL), hypotension/shock, DIC and conculsion

Question 9

A drug used for the treatment of uncomplicated malaria that causes hypoglycemia?

Answer 9

Quinine - a powerful stimulant of pancreatic insulin secretion, which is still widely used for the treatment of both severe and uncomplicated falciparum malaria

Question 10

True or False: Are convulsions in cerebral malaria generalized?

Answer 10

TRUE

Question 11

Pathogenesis of Hypoglycemia in cerebral malaria

Answer 11

both a failure of hepatic gluconeogenesis and an increase in the consumption of glucose by the host and, to a much lesser extent, the malaria parasites.

Question 12

TRUE OR FALSE: In QUARTAN MALARIAL NEPHROPATHY, chronic or repeated infections with P. malariae may cause soluble immune complex injury to the renal glomeruli, resulting in the NEPHROTIC SYNDROME

Answer 12

TRUE

Question 13

TRUE OR FALSE: Childhood Burkitt’s lymphoma is strongly associated with Epstein-Barr virus (EBV) and with high transmission of P. falciparum

Answer 13

TRUE

Question 14

Definitive diagnosis of malaria

Answer 14

demonstration of asexual forms of the parasite in stained peripheral-blood smears.

Question 15

In severe malaria, a poor prognosis is indicated by what findings in microscopy?

Answer 15

Predominance of more mature P. falciparum parasites (i.e., >20% of parasites with visible pigment) in the peripheral-blood film or by the presence of phagocytosed malarial pigment in >5% of neutrophils

Question 16

WHO recommended first-line treatment for uncomplicated P. falciparum malaria in malaria-endemic areas

Answer 16

Artemisinin-based combination therapy (ACT)

Question 17

Drug for malaria that may exacerbate psoriasis?

Answer 17

Chloroquine and Hydroxycholoroquine

Question 18

How do you take Chloroquine, Hydoxycholorquine, and Mefloquine as chemoprophylaxis?

Answer 18

Begin 1–2 weeks before travel to malarious areas. Take weekly on the same day of the week while in the malarious areas and for 4 weeks after leaving such areas.

Question 19

How do you take Atovaquone-proguanil (Malarone) and primaquine as chemoprophylaxis?

Answer 19

Begin 1–2 days before travel to malarious areas. Take daily at the same time each day while in the malarious areas and for 7 days after leaving such areas.

Question 20

This drug is contraindicated in patients with G6PD and pregnancy?

Answer 20

Primaquine

Question 21

The only drug advised for pregnant women traveling to areas with drug-resistant malaria. This drug is generally considered safe in the second and third trimesters of pregnancy.

Answer 21

Mefloquine

Question 22

TRUE OR FALSE? Atovaquone-proguanil (Malarone) is not recommended if the estimated
glomerular filtration rate is <30 mL/min.

Answer 22

TRUE

Question 23

TRUE OR FALSE: Mefloquine is contraindicated for use by travelers with known hypersensitivity and by persons with active or recent depression, anxiety disorder, psychosis, schizophrenia, another major psychiatric disorder, or seizures

Answer 23

TRUE

Question 24

What is the primary mode of malaria transmission?
A) Contaminated food and water
B) Inhalation of infected droplets
C) Bite of an infected female Anopheles mosquito
D) Direct contact with an infected person

Answer 24

Answer: C) Bite of an infected female Anopheles mosquito

Rationale: Malaria is caused by protozoan parasites of the genus Plasmodium, which are transmitted to humans through the bite of an infected female Anopheles mosquito. It is not spread through food, air, or direct contact.

Question 25

Which Plasmodium species is most commonly responsible for severe malaria? A) Plasmodium vivax B) Plasmodium malariae C) Plasmodium falciparum D) Plasmodium ovale

Answer 25

Answer: C) Plasmodium falciparum Rationale: P. falciparum is the most virulent species, responsible for the majority of severe malaria cases, including cerebral malaria, multi-organ failure, and high mortality rates.

Question 26

What is the dormant form of Plasmodium found in P. vivax and P. ovale infections that can cause relapses? A) Trophozoites B) Schizonts C) Hypnozoites D) Merozoites

Answer 26

Answer: C) Hypnozoites Rationale: Hypnozoites are dormant liver-stage parasites in P. vivax and P. ovale infections that can remain in the liver for weeks to years, causing relapses.

Question 27

In which region is Plasmodium vivax more commonly found? A) Africa B) New Guinea C) Hispaniola D) Southeast Asia

Answer 27

Answer: D) Southeast Asia Rationale: P. vivax is more common in Central and South America, as well as Southeast Asia, whereas P. falciparum predominates in Africa, New Guinea, and Hispaniola.

Question 28

What is the primary reason for anemia in malaria patients? A) Vitamin B12 deficiency B) Hemolysis and splenic clearance of infected RBCs C) Decreased iron absorption D) Autoimmune destruction of RBCs

Answer 28

Answer: B) Hemolysis and splenic clearance of infected RBCs Rationale: Malaria-induced anemia occurs due to destruction of infected RBCs during schizogony, increased splenic clearance of RBCs, and ineffective erythropoiesis.

Question 29

Which genetic disorder provides protection against severe P. falciparum malaria? A) Cystic fibrosis B) Marfan syndrome C) Sickle cell disease D) Down syndrome

Answer 29

Answer: C) Sickle cell disease Rationale: Individuals with sickle cell trait (HbS) have a protective advantage against P. falciparum malaria because the parasite has difficulty surviving in their red blood cells.

Question 30

What is a characteristic clinical feature of cerebral malaria? A) Seizures and coma B) Diarrhea and dehydration C) Skin rash and joint pain D) Severe cough and chest pain

Answer 30

Answer: A) Seizures and coma Rationale: Cerebral malaria, caused by P. falciparum, presents with coma and generalized seizures due to sequestration of infected RBCs in brain capillaries.

Question 31

Which of the following is the World Health Organization's (WHO) first-line treatment for uncomplicated P. falciparum malaria? A) Chloroquine B) Artemisinin-based combination therapy (ACT) C) Doxycycline D) Primaquine

Answer 31

Answer: B) Artemisinin-based combination therapy (ACT) Rationale: WHO recommends ACT for uncomplicated P. falciparum malaria due to its high efficacy and ability to reduce resistance.

Question 32

What is the best laboratory test for diagnosing malaria? A) PCR test B) ELISA test C) Blood smear (thick and thin) D) Urine antigen test

Answer 32

Answer: C) Blood smear (thick and thin) Rationale: Microscopic examination of thick and thin blood smears remains the gold standard for malaria diagnosis, allowing identification of parasite species and density.

Question 33

Which antimalarial drug is contraindicated in patients with psychiatric disorders? A) Mefloquine B) Artemisinin C) Doxycycline D) Primaquine

Answer 33

Answer: A) Mefloquine Rationale: Mefloquine is contraindicated in individuals with a history of psychiatric disorders (e.g., depression, anxiety, schizophrenia) due to the risk of neuropsychiatric side effects.

Question 34

What is the recommended malaria prophylaxis for a pregnant woman traveling to a malaria-endemic area? A) Atovaquone-proguanil B) Mefloquine C) Doxycycline D) Primaquine

Answer 34

Answer: B) Mefloquine Rationale: Mefloquine is the only antimalarial recommended for pregnant women traveling to malaria-endemic areas, particularly in the second and third trimesters.

Question 35

Which chronic complication is associated with Plasmodium malariae infection? A) Hyperreactive malarial splenomegaly B) Quartan malarial nephropathy C) Burkitt’s lymphoma D) Non-cardiogenic pulmonary edema

Answer 35

Answer: B) Quartan malarial nephropathy Rationale: Chronic P. malariae infection can cause immune complex-mediated nephrotic syndrome, known as quartan malarial nephropathy.

Question 36

How long should travelers continue malaria prophylaxis after leaving an endemic area? A) 1 week B) 2 weeks C) 4 weeks D) 6 weeks

Answer 36

Answer: C) 4 weeks Rationale: Antimalarial prophylaxis should be continued for 4 weeks after leaving an endemic area to ensure that any parasites acquired during travel are cleared.

Question 37

Which of the following laboratory findings is associated with an increased risk of mortality in severe malaria? A) Hypoglycemia (<2.2 mmol/L) B) Mild thrombocytosis C) Normal serum creatinine D) Mildly elevated ALT/AST

Answer 37

Answer: A) Hypoglycemia (<2.2 mmol/L) Rationale: Severe malaria can cause hypoglycemia due to increased glucose consumption by the parasite and quinine-induced hyperinsulinemia, leading to poor prognosis.

Question 38

A patient with severe malaria has a serum lactate level of 6 mmol/L. What does this indicate? A) Normal metabolic function B) Mild dehydration C) Hyperlactatemia and poor prognosis D) Low risk of complications

Answer 38

Answer: C) Hyperlactatemia and poor prognosis Rationale: Hyperlactatemia (>5 mmol/L) is a marker of tissue hypoxia and impaired perfusion, often due to microvascular sequestration of parasitized red blood cells, leading to poor outcomes.

Question 39

Which of the following is a major manifestation of cerebral malaria? A) Brief headache episodes B) Mild confusion C) Unarousable coma persisting for >30 minutes after seizure D) Occasional dizziness

Answer 39

Answer: C) Unarousable coma persisting for >30 minutes after seizure Rationale: Cerebral malaria is characterized by a prolonged unarousable coma following a seizure, indicating severe neurological involvement and a poor prognosis.

Question 40

Which laboratory finding is associated with severe normochromic, normocytic anemia in severe malaria? A) Hematocrit <15% or hemoglobin <50 g/L B) Hematocrit >45% C) Hemoglobin >13 g/dL D) Increased platelet count

Answer 40

Answer: A) Hematocrit <15% or hemoglobin <50 g/L Rationale: Severe anemia in malaria results from hemolysis of parasitized RBCs, leading to a significantly low hematocrit and hemoglobin, often with high parasitemia (>10,000/μL).

Question 41

Which seizure pattern is most concerning for severe malaria? A) Brief focal seizures B) Single tonic-clonic seizure lasting <1 minute C) More than two generalized seizures in 24 hours D) Absence seizures with full recovery

Answer 41

Answer: C) More than two generalized seizures in 24 hours Rationale: Multiple generalized seizures in a short time indicate severe neurological involvement, which is a hallmark of cerebral malaria and associated with increased mortality.

Question 42

Which of the following antimalarial drugs is contraindicated in pregnant women? A) Chloroquine B) Doxycycline C) Hydroxychloroquine D) Mefloquine

Answer 42

Answer: B) Doxycycline Rationale: Doxycycline is contraindicated in children under 8 years and pregnant women due to its potential effects on bone and teeth development.

Question 43

How long should Atovaquone-proguanil (Malarone) be continued after leaving a malaria-endemic area? A) 3 days B) 7 days C) 4 weeks D) 8 weeks

Answer 43

Answer: B) 7 days Rationale: Atovaquone-proguanil should be taken daily while in malaria-endemic areas and continued for 7 days after leaving to ensure any remaining parasites are cleared.

Question 44

Which antimalarial is preferred for prophylaxis in areas with chloroquine-resistant Plasmodium falciparum? A) Hydroxychloroquine B) Chloroquine C) Doxycycline D) Primaquine

Answer 44

Answer: C) Doxycycline Rationale: Doxycycline is recommended for prophylaxis in areas with chloroquine- or mefloquine-resistant P. falciparum.

Question 45

Which antimalarial should be avoided in individuals with a history of psychiatric disorders or seizures? A) Chloroquine B) Mefloquine C) Doxycycline D) Hydroxychloroquine

Answer 45

Answer: B) Mefloquine Rationale: Mefloquine has been associated with serious neuropsychiatric effects, including depression, anxiety, and seizures, making it unsuitable for individuals with such histories.

Question 46

Which of the following drugs should NOT be given to individuals with G6PD deficiency? A) Hydroxychloroquine B) Primaquine C) Mefloquine D) Doxycycline

Answer 46

Answer: B) Primaquine Rationale: Primaquine can cause hemolysis in individuals with glucose-6-phosphate dehydrogenase (G6PD) deficiency, making it contraindicated in such patients.