Archive Of Standardized Exam Questions: Malaria (Plasmodium Species)

OVERVIEW

This page is dedicated to organizing various examples of standardized exam questions whose answer is malaria. While this may seem a odd practice, it is useful to see multiple examples of how malaria will be characterized on standardized exams (namely the boards and the shelf exams). This page is not meant to be used as a tradition question bank (as all of the answers will be the same), however seeing the classic “test” characterization for a disease is quite valuable.

KEY CHARACTERISTICS OF THIS CONDITION (ON EXAMS)

When it comes to standardized exams, each topic has its own “code” marked by key buzzwords, lab findings, clues, etc. If you are well versed in this code you will be able to more quickly identify the condition that is being discussed, and get the right answer on the exam you are taking. Below is the “code” for malaria. 

  • Travel/residence to an endemic area: Africa
  • Symptoms: include fever headache, anemia, splenomegaly. The exact symptoms will depend on the organism that has cause the infection.
  • Blood smear: exact findings can vary depending upon the causal organism.
    • Trophozoite ring form within RBCs: 
    • Red granules in the cytoplasm: seen in P. vivax/ovale
QUESTION EXAMPLES

Question # 1

A 3 year old African American boy is brought to the hospital because he has a fever. Ever since returning from a family trip to Ghana last week, he has been very lethargic and has been complaining of a headache and nausea. He has also had several episodes of vomiting and watery diarrhea each day. His parents also explain that the he has had high spiking fevers, chills, and drenching sweats as well. The boy’s past medical history is notable for his diagnosis of sickle cell trait. He does not have any allergies, takes no medications, and all of his vaccinations are up to date. His temperate is 103.9°F, blood pressure is 90/55 mm Hg, push is 135/min, and respirations are 25/min. A physical exam shows a tired appearing boy who is jaundiced. Hepatosplenomegaly is present. The rest of the exam is non-contributory. Lab studies are conducted and reveal both anemia and thrombocytopenia. What is the likely diagnosis in this patient?

Explanation # 1

 

Question # 2

I 35-year-old male comes to the emergency room because of headaches, fever, and fatigue. He has developed intense chills with shivering, followed by high-grade fever’s and then perfuse sweating. A few days ago, the patient explained that he experienced similar symptoms that seem to go away. Both he and his wife returned from two weeks ago. His wife experience diarrhea dream trip but had no other symptoms. The patient has no notable past medical history and does not take any chronic medications. He was in the Pacific Northwest and works as a business consultant. He did not go on any other travels prior to his safari trip. Patient was vaccinated fever before his trip and has received no other vaccines recently. When the patient was in Kenya he explains that that he wore a long sleeve clothing, and do not drink a bottle water or eat raw food. His temperature is 102.3°F, blood pressure is 110/60 mmHg, his pulse is 115 per minute and respirations are 18 per minute. His physical exam is only notable for conjunctival pallor. Lab studies are shown below:

  • Hemoglobin: 10.7 g/dL
  • Hematocrit: 33%
  • Platelets: 105,000/mm³
  • Leukocytes: 11,000/mm³

What is the likely diagnosis in this patient?

Explanation # 2

Cyclic pattern of chills/fevers that come and go + recent travel to endemic area = malaria

Question # 3

 

Explanation # 3

 

 

TESTABLE FACTS ABOUT THIS TOPIC (BEYOND ITS IDENTIFICATION)

Many questions on standardized exams go beyond simply recognizing the underlying topic. Often there are specific testable facts regarding some aspect of the topic’s pathophysiology/management/clinical implications that are commonly asked. Some of these are listed below:

  • Which strains have dormant form: P. vivax/ovale form hypnozoite (dormant form) that will stay in the liver.
  •  Treatment
    • Chloroquine (for sensitive species): blocks Plasmodium heme synthesis
      • Mefloquine/atovaquone/proguanil: for species resistant to chloroquine.
    • Primaquine added to treatment for P. vivax/ovale strains: because these have hypnozoites that will remain in the liver.

 

 

 

Page Updated: 11.24.2016