PROTOZOAN (Coccidia) Flashcards
memorization
Alternation of generation occurs in the same host:
Monoxenous
Alternation of generation occurs in different hosts:
Heteroxenous
Plasmodium species
Intermediate host:
Definitive host:
Plasmodium species
Intermediate host: Humans
Definitive host: Mosquito
Plasmodium species
Sexual stage:
Asexual stage:
Plasmodium species
Sexual stage: Mosquito
Asexual stage: Humans
Malaria type of P. falciparum:
Malignant tertian malaria
- Blackwater fever
Malaria type of P. vivax:
Benign tertian malaria
Malaria type of P. malariae:
Quartan malaria
Malaria type of P. ovale:
Tertian malaria
Malaria type of P. knowlesi:
Quotidian malaria
Plasmodium species that has TRUE RELAPS:
- P. vivax
- P. ovale
Plasmodium species that infect young/immature RBCs:
- P. vivax
- P. ovale
Plasmodium species that infect old/senescent RBCs:
P. malariae
Plasmodium species that infect all ages of RBCs:
- P. falciparum
- P. knowlesi
Inclusion/stippling present in. P. falciparum:
Maurer’s
Inclusion/stippling present in. P. vivax:
Shuffner’s
Inclusion/stippling present in. P. malariae:
Ziemann’s
Inclusion/stippling present in. P. ovale:
Jame’s/Shuffner’s
Inclusion/stippling present in. P. knowlesi:
Stinton and Mulligan’s
Ring forms (young troph):
Delicate small ring with 2 chromatin dot; applique forms present
P. falciparum
Ring forms (young troph):
1/3 of cell diameter’ heavy chromatin dot
P. vivax
Ring forms (young troph):
Larger and more amoeboid than P. vivax
P. ovale
Ring forms (young troph):
Resembles falciparum applique, 2 chromatin dots:
P. knowlesi
Amoeboid form Trophozoites:
P. vivax
Band shaped trophozites:
- P. malariae
- P. knowlesi
Ring shape trophozoites:
P. ovale
Schizonts fill the entire RBC
P. vivax
Schizontes: Rosette or daisy head; Evenly distributed
P. malariae
Schizonts: Rosette or irregular cluster (irregular distribution)
P. ovale
Plasmodium species that has crescent or sausage-shaped gametocytes:
P. falciparum
Rounded/ oval gametocytes with homogenous cytoplasm:
P. vivax
P. malariae
P. ovale
P. knowlesi
What causes true relapse?
Reactivation of HYPNOZOITES; a dormant, nonreplicating form of Plasmodium parasite that can occur inside liver cells after invasion by sporozoites of the species P. vivax, P. ovale
Blood group characteristic that is resistant to P. vivax:
Fy (a-b-)
Blood group characteristics that is resistant to P. falciparum:
- Sickle cell trait and anemia
- G6PD deficiency
Gold standard for diagnosing malaria:
Thick and thin smear
Preferred sample for microscopic examination for malaria:
Capillary blood
Thick smear preparation:
____ drops of blood, _____ cm away from the smear, _____ cm diameter:
3 drops of blood
1 cm away from the smear
1 cm diameter
Blood smear in thick smear must _____ to allow dehemoglobinization (lyse RBC)
must not be fixed
How many OIF must be finished in examination of Thick smear:
100 OIF
Thin smear preparation:
______ large drop of blood
1 large drop of blood
Thin smear should ______ to prevent cell lysis.
Thin smear should be fixed with mehanol
Thick smear purpose:
Thin smear purpose:
Thick smear purpose: For rapid DETECTION
Thin smear purpose: For SPECIES IDENTIFICATION
Malarial antigen found ONLY in P. falciparum:
Histidine protein 2 (HRP-2)
Malarial antigen can be found in all malarial parasites:
- Parasite Lactate Dehydrogenase (pLDH)
- Plasmodium aldolase
Test that is only positive for P. falciparum:
Parasight F - detects HRP-2
Test that detects both HRP-2 and pLDH:
OptiMAL test
OptiMAL test interpretation:
+2 lines:
+3 lines:
OptiMAL test interpretation:
+2 lines: All except P. falciparum
+3 lines: P. falciparum
Immunochromatography test that detects HRP-2 and plasmodium aldolase
ICT Malaria P. f/P. v
ICT Malaria P. f/P. v test interpretation:
+2 lines:
+3 lines:
ICT Malaria P. f/P. v test interpretation:
+2 lines: all except P. falciparum
+3 lines: P. falciparum
Babesia microti resembles P. falciparum ring forms but:
No malarial pigments
Babesia microti
Intermediate host:
Definitive host:
Babesia microti
Intermediate host: Man (or other mammals)
Definitive host: Ixodid ticks
Pathogenesis of B. microti
Babesiosis
- headache
- fever
- hemolytic anemia with hemoglobinuria
Causative agent of Red Water fever in cattles:
Babesia bigemina
Mode of transmission of intestinal coccidia:
Fecal-ral route through water, food, meat
Habitat of intestinal coccidia:
Small intestines. They invade enterocytes causing malabsorption & diarrhea
Monoxenous intestinal coccidia species:
- Isospora belli
- Cryptosporidium parvum
- Cyclospora cayetanensis
Note: part of “No MILCC” mnemonic, Acid-Fast organisms
“ICC” acid-fast protozoans
Heteroxenous coccidia:
Sarcocystis species
Isospora belli
Infective stage:
Diagnostic stage:
Isospora belli
Infective stage: Mature oocyst
Diagnostic stage: Immature oocyst
Disease caused by Isospora belli
Isosporiasis - diarrhea in immunocompromised person
Cryptosporidium parvum
Infective stage:
Diagnostic stage:
Cryptosporidium parvum
Infective stage: Mature oocyst
- Thick-walled = external
- Thin-walled = internal
Diagnostic stage: Mature oocyst
Diseases caused by Cryptosporidium parvum:
- Water-borne parasite causing Gay bowel syndrome
- Pulmonary Sporidiosis
*can cause autoinfection
Cyclospora cayetanensis
Infective stage:
Diagnostic stage:
Cyclospora cayetanensis
Infective stage: Mature oocyst
Diagnostic stage: Immature oocyst
Diseases caused by Cyclospora cayetanensis
- Cyclosporiasis
- Cyclosporidiosis
Sarcocystis species
Infective stage:
Diagnostic stage:
Sarcocystis species
Infective stage: Mature oocyst (thin-walled)
- Sporocyst
- Encysted bradyzoites in undercooked meat
Diagnostic stage: Mature oocyst (thin-walled) sporocyst
Disease caused by Sarcocystis lindemanni:
- Diarrhea in immunocompromised host
- Myalgia (muscle pain)
Toxoplasma stage ingested when eating undercooked meat or other animals:
Zoitocyst
Toxoplasma stage transmitted in blood transfusion:
Tachyzoites
Toxoplasma stage transmitted in organ transplantation:
- Zoitocyst
- Tachyzoites
- Bradyzoite
Toxoplasma stage transmitted from mother to fetus:
Tachyzoites
SABIN’S TETRAD in toxoplasmosis:
- Retinochoroiditis
- Cerebral calcification
- Hydrocephalus or microencephalus
- Seizures
Diagnostic stage of Toxoplasmosis:
Toxoplasmosis (Toxoplasma gondii)
Diagnostic stage:
- Tachyzoites (blood)
- Zoitocyst (tissue)
Sabin-Feldman dye test (+) result for toxoplasmosis:
(+) Toxoplasma trophozoites are not stained (with methylene blue) because their cell membrane are destroyed by the complement activated by the Ab-Ag complex
