Lec 20 Arthropod-Borne Infections

Question 1

True of dengue virus EXCEPT

A. spherical particle with single-stranded DNA
B. has 7 non-structural proteins
C. most infections are asymptomatic
D. short-term cross protection against other serotypes

Answer 1

A

It is an RNA virus.

Question 2

ID: Mosquito vectors of dengue.

Answer 2

Aedes aegypti

Aedes albopictus

Question 3

Found in temperate regions

A. Aedes aegypti
B. Aedes albopictus
C. both
D. none

Answer 3

B

Question 4

Typically feeds and rests indoors

A. Aedes aegypti
B. Aedes albopictus
C. both
D. none

Answer 4

A

Question 5

Found in the tropics and subtropics

A. Aedes aegypti
B. Aedes albopictus
C. both
D. none

Answer 5

C

Question 6

What is the intrinsic incubation period of dengue?

Answer 6

4-13 days

Question 7

Primary dengue infection may result in the following EXCEPT

A. dengue fever
B. subclinical infection
C. undifferentiated febrile syndrome
D. dengue shock syndrome
E. AOTA

Answer 7

D

DSS happens after the 2nd dengue infection

Question 8

What cells do dengue viruses infect first?

Answer 8

immature dendritic cells in the skin

Question 9

What is the first noticeable laboratory finding in a person infected with dengue?

Answer 9

low WBC count

Question 10

Enumerate the clinical manifestations of dengue fever.

Answer 10

fever
retro-orbital pain
headache
muscle and joint pain
anorexia
rash

Question 11

True of the torniquet test EXCEPT

A. Torniquet is tied midway through the arm.
B. Test is done for 5 minutes
C. Counting is done on an area of 1 square inch.
D. Positive test is 20 or more petechiae per square inch.
E. NOTA

Answer 11

A

Torniquet is not used in the torniquet test.
You use BP cuff and inflate midway between the systolic and diastolic pressures.

Question 12

T/F: The patient is viremic during the critical phase.

Answer 12

F

The patient is viremic only during the febrile phase.

Question 13

During the critical phase, which occurs first?

A. leukopenia
B. thrombocytopenia
C. hemoconcentration
D. anemia
E. NOTA

Answer 13

A

leukopenia

Question 14

What is the main underlying cause of the warning signs seen in the critical phase?

Answer 14

plasma leakage due to increased capillary permeability

Question 15

Severe dengue is characterized by the following EXCEPT

A. severe plasma leakage
B. severe bleeding
C. severe organ impairment
D. severe anemia
E. NOTA

Answer 15

D

The patient is polycythemic NOT anemic.

Question 16

The critical phase of dengue lasts for how long?

Answer 16

24-48 hours

Question 17

Which of happens first during the recovery phase?

A. defervescence
B. WBC rise
C. platelet count rise
D. hemodilution

Answer 17

A

defervescence - WBC rise - hemodilution - platelet count rise

Question 18

What is the main differential of dengue fever?

Answer 18

chikungunya

Question 19

Which rises faster and higher during a secondary dengue infection?

A. IgM
B. IgG
C. both
D. secondary infection does not involve antibodies

Answer 19

B

IgG - rapid and higher increase

Question 20

WHO 1997 Criteria for dengue fever include the ff EXCEPT

A. leukopenia (

Answer 20

D

20% increase is already a sign of plasma leakage therefor it is already dengue HEMORRHAGIC fever

5-10% Hct increase only for uncomplicated dengue fever

Question 21

DHF patient presenting with platelet count 57,000, spontaneous bleeding, weak pulse, and 15 mmHg pulse pressure. The patient has DHF grade

A. Grade I
B. Grade II
C. Grade III
D. Grade IV

Answer 21

C

Question 22

What sign, apart from those in Grades 1-3, must be present to be classified DHF as Grade IV?

Answer 22

profound shock

- undetectable BP and pulse

Question 23

T/F: The 1997 criteria has high sensitivity.

Answer 23

F

Question 24

DHF Grades III and IV are collectively termed as what?

Answer 24

dengue shock syndrome

Question 25

Patient has 2 day history of fever, myalgia, retro-orbital pain, and nausea. Laboratory test showed leukopenia and (+) dengue IgM antibody. Based on the 2011 DOH revised classification, the patient has ``` A. probable dengue fever B. confirmed dengue fever C. dengue fever with warning signs D. severe dengue E. a condition other than dengue ```

Answer 25

A probable dengue fever only A confirmed dengue fever should have (+) viral isolation or (+) PCR

Question 26

Which is can be used for rehydration? ``` A. reduced osmolarity ORS B. high sodium, high glucose ORS C. gatorade or similar sports drink D. plain water E. AOTA ```

Answer 26

``` A reduced osmolarity (Na: 50-70 mmol/L) ```

Question 27

First line IV fluid for dengue shock A. crystalloids B. colloids C. NOTA D. AOTA

Answer 27

A

Question 28

Which is not recommended for transfusion? A. packed RBC B. fresh whole blood C. platelet concentrate D. NOTA

Answer 28

C platelet concentrate - may exacerbate fluid overload

Question 29

ID: Vector of chikungunya.

Answer 29

Aedes aegypti Aedes albopictus same as dengue

Question 30

ID: hallmark of chikungunya

Answer 30

severe and often debilitating joint pains

Question 31

The following are true in the recent (ca. 2005-2008) chikungunya pandemic EXCEPT A. more efficient viral replication in Ae. aegypti B. spread in temperate countries C. unusual clinicopathologic complications D. high morbidity

Answer 31

A Aedes albopictus

Question 32

T/F: Co-infection of dengue and chikungunya results in more severe or additive symptoms.

Answer 32

F

Question 33

3-day fever with myalgia and mild arthralgia. Which can you prescribe? ``` A. paracetamol B. ibuprofen C. aspirin D. celecoxib E. AOTA ```

Answer 33

A Do not prescribe NSAIDs or aspirin. Case may be a possible dengue and these drugs are contraindicated.

Question 34

More headache, body ache, and abdominal pain. A. dengue B. chikungunya

Answer 34

A