MALARIA Flashcards
(101 cards)
1
Q
True or False: Apicomplexans are extracellular protozoans
A
FALSE: Apicomplexans are intracellular organisms—lives inside a host/cell. For this particular parasite, Apicomplexans they are found inside the red cells
2
Q
Which species of Plasmodium is the most prevalent in the Philippines? Give the complete scientific name
A
Plasmodium falciparum : most prevalent in the Philippines and the most dangerous
3
Q
________ are dormant exo-erythrocytic stages present in the liver of P. vivax infected patients.
A
Hypnozoite : the dormant stage that are found inside the liver; the stage primarily responsible for malarial relapse
4
Q
What is the preferred stain for the preparation of malarial smears
A
Giemsa : best for detecting blood parasites—malarial parasites
5
Q
True or False: The detection of hrp-2 antigen in blood samples is associated with P. vivax infections
A
False : Histidine-rich protein 2 (hrp-2) is a specific marker for Plasmodium falciparum
6
Q
Take note, the malarial parasite belong to the Phylum
A
Phylum Apicomplexa
7
Q
The unique characteristic of Apicomplexa:
A
apex/apical complex which is used for penetration. Remember that Apicomplexans are intracellular and they use this component—apex/apical complex—to penetrate the cell
8
Q
Apicomplexans have complex life cycle which is
A
Alternating sexual and asexual stages
9
Q
Final Host: Intermediate host Habitat MOT IS to FH IS to IH
A
Final Host: Mosquito (Female Anopheles) Intermediate host: Man Habitat: : Liver, RBCs MOT : Bite of mosquito IS to FH: Gametocyte IS to IH: Sporozoites
10
Q
Vector of malaria
A
Bite of mosquito
11
Q
Only one that can feed on blood and the sporozoite must live long enough to develop and move to the salivary gland which is found only in
A
Female Anopheles
12
Q
Harbor sexual stage of the parasite
A
Final Host: Mosquito (Female Anopheles)
13
Q
harbors the asexual stage of the parasite
A
Intermediate Host: MAN
14
Q
Habitat of malaria if it undergoes exo-erythrocytic cycle
A
Liver
15
Q
Habitat of malaria if it undergoes erythrocytic cycle
A
Red blood cell
16
Q
Female Anopheles are usually
A
night-biter
17
Q
For the mosquito to be infected by the malarial parasite, the mosquito must get this stage found in humans
A
gametocyte
18
Q
Mosquito bites inject this stage to the human
A
sporozoites
19
Q
Gametocyte:
Sporozoites:
A
Gametocyte: Humans
Sporozoites: Female Anopheles
20
Q
what are the 5 Species:
A
Plasmodium falciparum Plasmodium vivax Plasmodium ovale Plasmodium malariae Plasmodium knowlesi
21
Q
In the Philippine setting, this is the most common malarial parasite, followed by Plasmodium vivax
A
Plasmodium falciparum
22
Q
Roughly 90% of the total infection in the Philippine setting is actually brought by the combination of
A
Plasmodium falciparum and Plasmodium vivax
23
Q
a malarial parasite that is rare or not encountered in the Philippines
A
Plasmodium ovale
24
Q
a malarial parasite that is also detected in Philippines
A
Plasmodium malariae
25
a malarial parasite that is a zoonotic infection because this is isolated from monkeys
Plasmodium knowlesi
26
This is the malarial parasite of the old world monkeys
Also detected in Philippines and other Southeast Asian countries
Plasmodium knowlesi
27
mistaken as P. malriae because they are morphologically the same
Plasmodium knowlesi
28
the major way to differentiate P. knowlesi from P. malariae is through
Polymerase Chain Reaction (PCR) – a nucleic acid test
29
most common cause of malarial infection in the Philippine setting
Plasmodium falciparum
30
three (3) malarial stages detected in humans:
trophozoite
schizont
gametocyte
31
Malarial stage detected in human:
growing form
ring form (young)
amoeboid form
trophozoite
32
Malarial stage detected in human:
| dividing form
Schizont
33
1 schizont =
multiple merozoites
34
P. falciparum is said to be the deadliest because it has
more merozoites compared to other Plasmodium species
35
Malarial stage detected in human:
Sexual form
infective stage to the mosquito
has two forms
Gametocyte
36
2 forms of gametocyte
Microgametocyte (male)
| Macrogametocyte (female)
37
both malarial specie infects red cells of normal size
P. falciparum and P. malariae
38
Red cell of this Form of P. falciparum in thin smear that has single chromatin mass and abundant cytoplasm
Plasmodium falciparum ring form (trophozoite stage)
39
P. falciparum ring form in thick smear has (2)
no red cells and not dehemoglobinized
40
ring forms found protruding on the surface of red cells mostly in P. falciparum infection
Appliqué or Accollé
41
Characteristic that is common in P. falciparum infection (but can be found in other species as well)
Double ring form / Double chromatid dot
42
ratio of red cell infected to parasite for--
Most malarial parasites:
P. falciparum:
Most malarial parasites: 1:1
| P. falciparum: 1:1 or 1:2 (one red cell infected by two parasites resulting to the double ring form)
43
most of the malarial parasites (except P. falciparum) have
ring forms inside the red cells
44
stage of p. falciparum in a thin blood smear has numerous merozoites = multiple infection in one red cell
can be mature or immature
once the red cell ruptures, merozoites are released and can infect another red cell
Schizont of P. falciparum
45
P. falciparum is considered the most dangerous malarial parasite because it has
the highest number of merozoites in a single red cell
46
Stage of P. falciparum that is usually not detected in blood smear unless it is already a severe malaria
Schizont of P. falciparum
47
another way to identify malarial parasite is
by determining the number of merozoites in a schizont (each malarial parasite has a corresponding merozoite number
48
Schizont of P. falciparum characteristics
Accole, applique form, double chromatin
49
Stage of P. falciparum that is Banana-shaped or sausage shaped; usually elongated;
Gametocyte of P. falciparum
50
Type of gametocyte that has
Chromatin mass - dots inside
Compact chromatin mass
Macrogametocyte
51
Type of gametocyte that has dispersed / scattered chromatin mass
Microgametocyte
52
Second most common parasite in the Philippines
Plasmodium vivax
53
Type of Plasmodium specie in which:
Infected RBCs are usually larger as compared to the uninfected cell (including that of P. ovale)
Has enlarged RBCs
Plasmodium vivax
54
rare to see the mature trophozoite form in what Plasmodium specie
Plasmodium falciparum
55
Common to see trophozoite form in what Plasmodium specie
Plasmodium vivax
56
A distinct characteristic seen in mature trophozoite stage (not seen in ring form) or P. vivax
Seen in almost all erythrocytes that contain the mature stages of the malarial parasite
Denotes the Degradation product of hemoglobin
Hemozoint pigments
57
Type of malarial specie by which:
Merozoites are seen
1 merozoite will infect 1 red cell
Number of merozoite is one way to differentiate malarial parasites.
P.vivax Schizonts Stage
58
Usually rounded (for vivax, ovale, malariae); sausage or banana-shaped (for falciparum)
P.vivax Gametocyte
59
Hemozoint pigment of P. vivax
Schuffner dots
Other types: Stephen, Christopher, Maurer's dots
60
Fifth malarial parasite of man
Plasmodium malariae
61
Malarial specie (and stage) that has Band trophozoite
Plasmodium malariae
62
Malarial specie (and stage) in which the Infected red cells are normal in size
Plasmodium malariae trophozoite
63
Malarial specie (and stage) in which:
Merozoite in fruit pie or rosette appearance
Paikot ang merozoite formation
Plasmodium malariae schizont stage
64
Red cell of this malarial specie is fimbriated (irregular projection) though not yet encountered in PH
Plasmodium ovale
65
Cycle found in the red cell
| when Red cells are infected
Febrile/Erythrocytic Cycle
66
```
What do you call the Febrile/Erythrocytic Cycle of each malarial species
Plasmodium falciparum:
Plasmodium vivax:
Plasmodium ovale:
Plasmodium malariae:
Plasmodium knowlesi:
```
Plasmodium falciparum: Malignant Tertian
Plasmodium vivax: Benign Tertian
Plasmodium ovale: Ovale Tertian
Plasmodium malariae: Quartan Malaria
Plasmodium knowlesi: Quotidian Malaria
67
Febrile/Erythrocytic Cycle
| Fever every 36-48 hrs
Plasmodium falciparum: Malignant Tertian
68
Febrile/Erythrocytic Cycle
| Fever every 48hrs
Plasmodium vivax: Benign Tertian
and
Plasmodium ovale: Ovale Tertian
69
Febrile/Erythrocytic Cycle
| Fever every 72hrs
Plasmodium malariae: Quartan Malaria
70
Febrile/Erythrocytic Cycle
Non-relapsing
Lacks exoerythrocytic stage
Plasmodium knowlesi: Quotidian Malaria
71
GOLD standard in diagnosing malarial infection
Thick and Thin Smear
72
Best stain for malarial/blood parasite is ___
| alternative is ___
Giemsa
| Wright stain
73
Smear for parasite screening, sensitivity
Thick smear
74
Smear for identification, specificity
Thin smear
75
3 Factors to consider in examining smears
Appearance of the infected Red cell
Appearance of the parasite
Stages found
76
Dehemoglobinizing agent in thick smear
Water
77
type of smear:
| Dehemoglobinize using water prior to staining
Thick smear
78
type of smear:
| Stain immediately; no need to fix with MEOH (methanol)
Thick smear
79
Utilizing more blood – more sensitive to detect presence or absence of malarial parasite
Thick smear
80
Use this type of smear for qualitative reporting
Thick smear
81
We can report negative if there is no malarial parasite present per
100 FIELDS
82
Use this type of smear to determine the number of malarial parasites per ul of blood
Thick smear
83
Formula of #malarial parasites/ul
of parasites counted / 200 WBCs x 8000
we use 8000, if not provided exact WBC count of the patient and if provided then we use the actual WBC count provided
84
type of smear:
Fix with MEOH (methanol)
Stain with Giemsa-recommended stain for malarial parasite, kung wala they can use Wright stain
Thin smear
85
```
Developing trophozoite (ameboid form)
is not usually detected in
```
Falciparum infection
86
presence of this in smear of Plasmodium falciparum infected cell means bad prognosis
presence of merozoite
87
The most common here is the amoeboid form
Plasmodium vivax
88
Malarial stage that is not usually detected in P. falciparum but is common in P. vivax
matured trophozoite / ameboid form
89
Form of P. vivax that is rounded compared to the P. falciparum which has sausage shape
Gametocyte form of P. vivax
90
3 Diagnostic tests for malarial infection
Rapid diagnostic test (RDTs)
Quantitative Buffy Coat (QBC)
Indirect Fluorescent antibody test (IFAT)
91
The principle of this test is immunochromatography (in nature)
Rapid diagnostic test (RDTs)
92
Advantages of this diagnostic test include:
you can have the result as fast as 15-30 mins. depending on the manufacturer
can be used without electricity and special equipment,
No need for training in microscopy
Rapid diagnostic test (RDTs)
93
Disadvantages of this diagnostic test include:
Lack of sensitivity at low levels of parasitemia, can result to a false negative result
can detect presence of malarial parasite but unable to quantify the parasite density *for malaria – we need both identity and count
Cannot differentiate plasmodium ovale, plasmodium malarae, and plasmodium vivax
That’s why In every RDT, it is reported as Plasmodium falciparum or other plasmodium species since there are no antigens yet to differentiate plasmodium ovale, plasmodium malarae, and plasmodium vivax
Persistent positive despite parasite clearance
You will be positive even if you are already treated. Maybe because there is still presence of circulating antigen
More expensive than thick and think blood smear
Rapid diagnostic test (RDTs)
94
This test Detect Plasmodium specific antigens:
-HRP-II or the Histidine Rich Protein II
specific for Plasmodium falciparum. produced by trophozoite and young gametocyte of Plasmodium falciparum
-Plasmodium Lactate Dehydrogenase (PLDH)
produced by sexual and asexual stage
can distinguish Plasmodium falciparum form non-Plasmodium falciparum
Plasmodium aldolase
This is produced by all plasmodium species
Rapid diagnostic test (RDTs)
95
This diagnostic test makes use of:
Capillary tube with acridine orange stain (florescence stain)
Blood will be centrifuged in a microhematocrit tube,
Then you will apply acridine orange stain and it will bind with to the nucleic acid of the malarial parasite
Bind particularly in the nucleus – contains nucelic acid
*rbcs are not stained, they do not have the nucleus
QUANTITATIVE BUFFY COAT (QBC)
96
color of a Positive result in QBC
(positive +) bright green and yellow under florescence microscope
97
Band formation, rosette arrange of merozoites and normal sized infected RBCs are all associated with which species of plasmodium? give the complete scientific name
Plasmodium malariae
98
True or False: IFAT detects antibodies against plasmodium
True
| indirect – detection of antibodies; direct – detection of antigen
99
Which species of plasmodium is endemic in Southeast Asia and can be mistaken for P. malariae?
Plasmodium knowlesi
100
sausage shaped gametocytes, accole and applique ring forms are all associated with which species of plasmodium? give the complete scientific name
Plasmodium falciparum
101
True or False: Fixation of the thick smear is required
False
| This is also used to the detect the malarial parasite
