Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Multisystems II > Microbiology-Malaria > Flashcards

Microbiology-Malaria Flashcards

1
Q

What are the 5 species of malaria that infect humans?

A

P. falciparum, P. vivax, P. ovale, P. malariae, P. knowlesi.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

How do you differentiate a malaria parasite from a platelet?

A

Platelets have more than one shade of the same color. Parasites always have a magenta nucleus and a blue cytoplasm.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What stage is this parasite in?

A

Ring trophozoite: note the ring, magenta chromatin and blue cytoplasm.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What stage is this parasite in?

A

Growing trophozoite: note the pigment granules, blue-purple cytoplasm and magenta chromatin.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What stage is this parasite in?

A

Mature trophozoite

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What stage is this parasite in?

A

Young Immature Schizont

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What stage is this parasite in?

A

Old Immature Schizont

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What stage is this parasite in?

A

Mature Schizont: note the pigment clump and merozoite

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Parasites that leave red cells the same color and size or slightly smaller than surrounding cells.

A

P. falciparum, P. malariae or P. knowlesi

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Parasites that do not leave red cells the same color and size.

A

P. vivax and P. ovale.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

This parasite has only small delicate rings, Mauer’s clefts, no trophozoites and very rare schizonts. It’s gametes look like bananas.

A

P. falciparum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Parasites with band and basket forms, pigment, a few chunky merozoites and all stages of development.

A

P. malariae and P. knowlesi

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Parasites that are extremely ameboid, have pigment, Schuffner’s dots and many merozoites?

A

P. vivax

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Parasites that are ameboid, have pigment and fimbriae, Shuffner’s dots and fewer merozoites?

A

P. ovale

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What parasite is seen on the thick smear below?

A

P. falciparum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What parasite is seen on the thick smear below?

A

P. malariae

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What parasite is seen on the thick smear below?

A

P. vivax

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What parasite is seen on the thick smear below?

A

P. ovale

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Fill in the blanks

A

*

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

OIFs

A

Oil immersion fields used to identify presence of malaria under microscopy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Quantitative measurements of malaria

A

*

22
Q

What type of pathogen is malaria? What does it infect?

A

Protozoa. It infects RBCs, these don’t have MHCs so it’s a good place to hide.

23
Q

A 28 year old woman presents with body aches, chills and a fever that morning. She has been working in Cameroon for the past two years. What do you need to do next?

A

Get a blood smear immediately. In non-immune patients falciparum malaria can kill in 24 hours.

24
Q

Patient returns from the tropics with a fever, what is the 1st thing you need to check?

A

Malaria, malaria, malaria! Check in any traveler with a fever, this is why you always have to ask a travel history.

25
Q

Risk factors for severe malaria

A

Nominate individuals (immunity wanes after living in non-endemic areas for ~5 years), children < 5, pregnant women, asplenic patients.

26
Q

5 species of malaria? Vector? Reservoir?

A

P. falciparum, P. vivax, P. ovale, P. malariae, P. knowlesi. Anophelene mosquito is the vector. All human reservoir except P. knowlesi which is found in macaques and people.

27
Q

Malaria most likely to kill people

A

P. falciparum

28
Q

Life cycle of malaria

A

Sporozoites injected into blood stream by mosquito -> Transformation into 10,000+ merozoites in hepatocytes -> Released back into blood stream -> Infects RBCs -> Forms trophozoites -> Matures into schizonts -> Forms more merozoites -> RBC ruptures and they infect more cells.

29
Q

Liver cells infected with malaria without amplification.

A

Hypnozoite: only happens with P. vivax and P. ovale. They remain dormant in liver cells for weeks to years and cause cyclic fevers.

30
Q

Malaria that takes the longest time to burst out of liver cells and cause infection

A

P. malariae. However, other types can take longer if chemoprophylaxis is not perfectly adherent.

31
Q

Malaria species that can cause an asymptomatic chronic erythrocyte infection for 20+ years that will present with fever at immunosuppression

A

P. malariae

32
Q

Necessary for spread from one person to another

A

Uptake of male and female gametocytes by mosquito to form trophozoites that will be injected from the salivary gland of the mosquito into another person.

33
Q

Traits in humans that evolved in malaria endemic countries

A

Sickle cell trait: red cells that are infected are more readily cleared because of sickling. G6PD. Duffy antigen negative RBCs (necessary for entry into RBCs)

34
Q

Classic symptoms of malaria

A

Fever, chills, headache

35
Q

Symptom that presents in travelers 20% of the time when they have malaria?

A

Abdominal pain/diarrhea

36
Q

Lab values that hint toward malaria

A

Elevated LDH, anemia and elevated bilirubin because of hemolysis.

37
Q

3 clinical types of malaria

A

Acute uncomplicated (all species), severe and hyper-reactive malarial syndrome (tropical splenomegaly).

38
Q

A patient comes in with chills, then develops a fever of 105 and then the fever breaks as the patient begins to sweat. These episodes last 6-10 hours, then recur. How many days apart would you expect to see these paroxysms if he was infected with P. vivax, P. ovale or P. falciparum? What if it were P. malariae?

A

Vivax, ovale and falciparum is seen every 2 days (tertian fever, basically every other day). P. malariae is every 3 days because this is how the parasites sync up with the red blood cell cycles.

39
Q

How does malaria kill people?

A

Severe malaria = damaged tissues. This differs by age. CHILDREN: cerebral malaria, respiratory distress and severe anemia. ADULTS: renal failure, hypoglycemia, shock and coagulopathy. Note that these are see when parasitemia > 2% in falciparum infection

40
Q

Important prognostic factors of malaria

A

Acidosis and parasitemia (>1% makes you worried).

41
Q

Why are falciparum infections most lethal?

A

They have no predilection for RBC age and no inhibition on the degree of parasitemia

42
Q

Why do tissues become hypoxic and patients acidotic with malaria?

A

Parasitized RBCs become sticky, stick against capillary walls (sequestration). This results in ischemia distal to the region of RBC sequestration. This is the cause of acute encephalopathy in patients with cerebral malaria, not infection of neurons.

43
Q

Why do people become hypoglycemic with malaria?

A

Increased metabolic rate due to infection and decreased consumption

44
Q

Why do people have renal failure with malaria?

A

Filtration of hemolyzes RBC products

45
Q

Why do people have anemia with malaria?

A

Hemolysis, sequestration and splenic removal.

46
Q

Diagnosing malaria

A

Blood smear, antigen testing and PCR.

47
Q

What do you do if someone has a fever but the malaria test was negative yesterday?

A

Test again

48
Q

Presentation of someone with malaria who took chemoprophylaxis?

A

Subacute

49
Q

What do you do if you are in the field and there are no diagnostic methods for malaria?

A

Treat empirically?

50
Q

Things to watch for in patients admitted with malaria

A

Respiratory compromise, hypoglycemia, neurologic changes…treat ASAP before they crash. Parasitemia > 5% with neurologic changes = IV therapy.

51
Q

If a patient has vivax or ovale what therapy should they receive?

A

Primaquine to eradicate remaining hypnozoites.

Multisystems II (32 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions