Lesson 6.1.h. Protozoa

Malaria

Tropical and subtropical worldwide

Plasmodium spp. (P. vivax, P. malariae, P. falciparum, P. ovale, P. knowlesi)

causative agent of Malaria

Anopheles

vector of malaria

Sporozoites

LIFE CYCLE SUMMARY

1. _____________ injected during mosquito feeding

2. Invade ____________

3. Liver replication produces _____________

4. Merozoites invade ____________

5. Repeated ______________________

6. _________________ infect mosquito

7. ____________________ in gut

8. ______________ on gut wall sporozoites invade salivary glands

1 = ?

liver cells

LIFE CYCLE SUMMARY

1. _____________ injected during mosquito feeding

2. Invade ____________

3. Liver replication produces _____________

4. Merozoites invade ____________

5. Repeated ______________________

6. _________________ infect mosquito

7. ____________________ in gut

8. ______________ on gut wall sporozoites invade salivary glands

2 = ?

Merozoites

LIFE CYCLE SUMMARY

1. _____________ injected during mosquito feeding

2. Invade ____________

3. Liver replication produces _____________

4. Merozoites invade ____________

5. Repeated ______________________

6. _________________ infect mosquito

7. ____________________ in gut

8. ______________ on gut wall sporozoites invade salivary glands

3 = ?

red blood cells

LIFE CYCLE SUMMARY

1. _____________ injected during mosquito feeding

2. Invade ____________

3. Liver replication produces _____________

4. Merozoites invade ____________

5. Repeated ______________________

6. _________________ infect mosquito

7. ____________________ in gut

8. ______________ on gut wall sporozoites invade salivary glands

4 = ?

Gametocytes

LIFE CYCLE SUMMARY

1. _____________ injected during mosquito feeding

2. Invade ____________

3. Liver replication produces _____________

4. Merozoites invade ____________

5. Repeated ______________________

6. _________________ infect mosquito

7. ____________________ in gut

8. ______________ on gut wall sporozoites invade salivary glands

5 = ?

erythrocytic schizogony

LIFE CYCLE SUMMARY

1. _____________ injected during mosquito feeding

2. Invade ____________

3. Liver replication produces _____________

4. Merozoites invade ____________

5. Repeated ______________________

6. _________________ infect mosquito

7. ____________________ in gut

8. ______________ on gut wall sporozoites invade salivary glands

6 = ?

Fusion of gametes

LIFE CYCLE SUMMARY

1. _____________ injected during mosquito feeding

2. Invade ____________

3. Liver replication produces _____________

4. Merozoites invade ____________

5. Repeated ______________________

6. _________________ infect mosquito

7. ____________________ in gut

8. ______________ on gut wall sporozoites invade salivary glands

7 = ?

Sporogony

LIFE CYCLE SUMMARY

1. _____________ injected during mosquito feeding

2. Invade ____________

3. Liver replication produces _____________

4. Merozoites invade ____________

5. Repeated ______________________

6. _________________ infect mosquito

7. ____________________ in gut

8. ______________ on gut wall sporozoites invade salivary glands

8 = ?

Recurrent chills and fever

SYMPTOMS AND PATHOLOGY

• synchronized rupture of red cells

36

Recurrent chills and fever

malignant tertian malaria

1. every _______ hours

2. causative agent:

1 = ?

P. falciparum

Recurrent chills and fever

malignant tertian malaria

1. every _______ hours

2. causative agent:

2 = ?

48

Recurrent chills and fever

ovale malaria

1. every _______ hours

2. causative agent:

1 = ?

P. ovale

Recurrent chills and fever

ovale malaria

1. every _______ hours

2. causative agent:

2 = ?

48

Recurrent chills and fever

benign tertian malaria

1. every _______ hours

2. causative agent:

1 = ?

P. vivax

Recurrent chills and fever

benign tertian malaria

1. every _______ hours

2. causative agent:

2 = ?

72

Recurrent chills and fever

quartan malaria

1. every _______ hours

2. causative agent:

1 = ?

P. malariae

Recurrent chills and fever

benign tertian malaria

1. every _______ hours

2. causative agent:

2 = ?

Anemia

SYMPTOMS AND PATHOLOGY

• red cell destruction

large spleen and joint pain

SYMPTOMS AND PATHOLOGY:

• other symptoms

Plasmodium falciparum

plasmodial infection most likely fatal

Cerebral malaria

Plasmodium falciparum causes:

a. red cells, organisms and pigment block brain vessels

b. sudden massive intravascular hemolysis with resultant hemoglobinuria

a = ?

Blackwater Fever

Plasmodium falciparum causes:

a. red cells, organisms and pigment block brain vessels

b. sudden massive intravascular hemolysis with resultant hemoglobinuria

b = ?

Plasmodium vivax

Plasmodial infection most widely disseminated and most prevalent

Glucose-6-phosphate dehydrogenase

INCOMPATIBLE WITH PARASITE SURVIVAL

1. ___________________________________ deficiency

2. ____________________ inheritance

3. ____________________________ (HbSS)

1 = ?

Duffy negative

INCOMPATIBLE WITH PARASITE SURVIVAL

1. ___________________________________ deficiency

2. ____________________ inheritance

3. ____________________________ (HbSS)

2 = ?

Hemoglobinopathies

INCOMPATIBLE WITH PARASITE SURVIVAL

1. ___________________________________ deficiency

2. ____________________ inheritance

3. ____________________________ (HbSS)

3 = ?

Plasmodium vivax (BENIGN TERTIAN MALARIA)

• 48-hour cycle

• Tends to infect young cells

• Enlarged RBCs

• Schüffner’s dots (true stippling) after 8-10 hours

• Delicate ring

• Very ameboid trophozoite

• Mature schizont contains 12-24 merozoites

Plasmodium malariae (QUARTAN MALARIA)

• § 72-hour cycle (long incubation period)

• Tends to infect old cells

• Normal size RBCs

• No stippling

• Thick ring, large nucleus

• Trophozoite tends to form “bands” across the cell

• Mature schizont contains 6-12 merozoites

Plasmodium falciparum (MALIGNANT TERTIAN MALARIA)

• 36-48-hour cycle

• Tends to infect any cell regardless of age, thus very heavy infection may result

• All sizes of RBCs

• No Schüffner’s dots (Maurer’s dots: may be larger, single dots, bluish)

• Multiple rings/cell (only young rings, gametocytes, and occasional mature schizonts are seen in peripheral blood)

• Delicate rings, may have two dots of chromatin/ring, appliqué or accolé forms

• Crescent-shaped gametocytes

Plasmodium ovale

• 48-hour cycle

• Tends to infect young cells

• Enlarged RBCs with fimbriated edges (oval)

• Schüffner’s dots appear in the beginning (in RBCs with very young ring forms, in contrast to P. vivax)

• Smaller ring than P. vivax

• Trophozoite less ameboid than that of P. vivax

• Mature schizont contains an average of 8 merozoites

Plasmodium knowlesi (SIMIAN MALARIA)

• 24-hour cycle

• Tends to infect any cell regardless of age, thus very heavy infection may result

• All sizes of RBCs, but most tend to be normal size

• No Schüffner’s dots (faint, clumpy dots later in cycle)

• Multiple rings/cell (may have 2-3)

• Delicate rings, may have two or three dots of chromatin/ring, appliqué forms

• Band form trophozoites commonly seen

• Mature schizont contains 16 merozoites, no rosettes

• Gametocytes round, tend to fill the cell

• Early stages mimic P. falciparum; later stages mimic P. malariae

Plasmodium species

TREATMENT SHOULD BE GUIDED BY THE FOLLOWING FOUR MAIN FACTORS:

1. Infecting __________________________

2. ___________________ of the patient

3. Expected ___________________ of the infecting parasite as determined by the geographic area where the infection was acquired

4. Previous use of _________, including those taken for malaria chemoprophylaxis

1 = ?

Clinical status

TREATMENT SHOULD BE GUIDED BY THE FOLLOWING FOUR MAIN FACTORS:

1. Infecting __________________________

2. ___________________ of the patient

3. Expected ___________________ of the infecting parasite as determined by the geographic area where the infection was acquired

4. Previous use of _________, including those taken for malaria chemoprophylaxis

2 = ?

drug susceptibility

TREATMENT SHOULD BE GUIDED BY THE FOLLOWING FOUR MAIN FACTORS:

1. Infecting __________________________

2. ___________________ of the patient

3. Expected ___________________ of the infecting parasite as determined by the geographic area where the infection was acquired

4. Previous use of _________, including those taken for malaria chemoprophylaxis

3 = ?

antimalarials

TREATMENT SHOULD BE GUIDED BY THE FOLLOWING FOUR MAIN FACTORS:

1. Infecting __________________________

2. ___________________ of the patient

3. Expected ___________________ of the infecting parasite as determined by the geographic area where the infection was acquired

4. Previous use of _________, including those taken for malaria chemoprophylaxis

4 = ?

Central America west of the Panama Canal, Haiti, and the Dominican Republic

P. falciparum or Species Not Identified — Acquired in Areas Without Chloroquine Resistance

a. For P. falciparum infections acquired in areas without chloroquine-resistant strains, which include _______________________________________________

b. patients can be treated with ________________________________________ at recommended doses.

a = ?

oral chloroquine, or, alternatively, hydroxychloroquine

P. falciparum or Species Not Identified — Acquired in Areas Without Chloroquine Resistance

a. For P. falciparum infections acquired in areas without chloroquine-resistant strains, which include _______________________________________________

b. patients can be treated with ________________________________________ at recommended doses.

b = ?

Artemether-lumefantrine (Coartem™)

For P. falciparum infections acquired in areas with chloroquine resistance

a. ___________________________________ which is the preferred option if readily available

b. used when letter a. is not available

c.____________________________________________ is also a treatment option.

d. For the quinine sulfate combination options, ____________________________ is generally preferred because there are more data on its efficacy

e. ____________, is associated with rare but potentially severe neuropsychiatric reactions when used at treatment dose.

a = ?

atovaquone-proguanil (Malarone™)

For P. falciparum infections acquired in areas with chloroquine resistance

a. ___________________________________ which is the preferred option if readily available

b. used when letter a. is not available

c.____________________________________________ is also a treatment option.

d. For the quinine sulfate combination options, ____________________________ is generally preferred because there are more data on its efficacy

e. ____________, is associated with rare but potentially severe neuropsychiatric reactions when used at treatment dose.

b = ?

Quinine sulfate plus doxycycline, tetracycline, or clindamycin

For P. falciparum infections acquired in areas with chloroquine resistance

a. ___________________________________ which is the preferred option if readily available

b. used when letter a. is not available

c.____________________________________________ is also a treatment option.

d. For the quinine sulfate combination options, ____________________________ is generally preferred because there are more data on its efficacy

e. ____________, is associated with rare but potentially severe neuropsychiatric reactions when used at treatment dose.

c = ?

quinine sulfate plus either doxycycline or tetracycline

For P. falciparum infections acquired in areas with chloroquine resistance

a. ___________________________________ which is the preferred option if readily available

b. used when letter a. is not available

c.____________________________________________ is also a treatment option.

d. For the quinine sulfate combination options, ____________________________ is generally preferred because there are more data on its efficacy

e. ____________, is associated with rare but potentially severe neuropsychiatric reactions when used at treatment dose.

d = ?

Mefloquine

For P. falciparum infections acquired in areas with chloroquine resistance

a. ___________________________________ which is the preferred option if readily available

b. used when letter a. is not available

c.____________________________________________ is also a treatment option.

d. For the quinine sulfate combination options, ____________________________ is generally preferred because there are more data on its efficacy

e. ____________, is associated with rare but potentially severe neuropsychiatric reactions when used at treatment dose.

e = ?

P. malariae and P. knowlesi species

There has been no widespread evidence of chloroquine resistance in ____________________________; therefore, chloroquine (or hydroxychloroquine) may still be used for both of these infections.

Papua New Guinea or Indonesia

Chloroquine (or hydroxychloroquine), remains an effective choice for P. vivax and P. ovale infections except for P. vivax infections acquired in ____________________, countries with high prevalence of chloroquine-resistant P. vivax

artemether-lumefantrine, atovaquone-proguanil, or quinine sulfate plus doxycycline or tetracycline (or clindamycin for pregnant women and children<8 years old),

If chloroquine is not available, or for persons acquiring P. vivax infections in Papua New Guinea or Indonesia, treatment with a regimen recommended for chloroquine-resistant P. vivax infections is appropriate.

1. These include _________________________________________________ and are equally recommended.

2. Mefloquine can be used if no other options are available, because of rare but potentially severe ________________________ when used at treatment dose.

1 = ?

neuropsychiatric reactions

If chloroquine is not available, or for persons acquiring P. vivax infections in Papua New Guinea or Indonesia, treatment with a regimen recommended for chloroquine-resistant P. vivax infections is appropriate.

1. These include _________________________________________________ and are equally recommended.

2. Mefloquine can be used if no other options are available, because of rare but potentially severe ________________________ when used at treatment dose.

2 = ?