Protozoa Flashcards
(18 cards)
Entamoeba histolytica
contaminated food (cysts)-> small intestine (megacyst)-> large intestine ( 8 trophozoites)-> colonize
-Amoebic dysentery (ambebiasis)->button hole ulcers->liver abscesses
-NO CYSTS in active phase
-NO FEVER
Acute phase: triggered by bacteria (bloody stools)
Severe case: ectopic lesion-> RUQ pain
-asymptomatic carriers SPREAD
-Mexico
-nigh soil/veneral spread/careless plumbing
-ID cysts in stools, troph (diarrhea), ultrasound, MRI, CT liver
-metronidazole/tetracycline, iodoquinol or paromomcyin (control)
-wash veges, boil water,
Giardia lamblia
-intestinal flagellate
-troph (8 flagella, 2 nuclei) transmission, liquid stools
-cysts (formed stools)
-Trophs interfere with FAT absorption
-eat contaminated food with CYSTS-> duodenum-> trophs, live on surface villi -> convert to cysts in large intestine-> stools
-daycare centers, fecal-oral route
-dogs and muskrat reservoirs
Metronidazile, Nitrazoxanide, tinidazole, treat whole family and dogs
-cysts look like footballs, (or jellyfish)
trichomonas vaginalis
NO CYSTS, infected by trophs
- increases pH of vagina
- persistent vaginitis, itchy, yellowish/green discharge
- metronidazole, vinegar douche
- treat all partners
cryptosporidium parvum
- intestinal sporozoan
- fecal-oral contamination
- ingest oocysts-> asexual reproduction in intestinal epithelium-> form oocysts-> in feces
- PROFUSE WATERY DIARRHEA
- respiratory effect in IC’s
- related to cyclospora (watery diarrhea, Guatemalan raspberries)
- daycares, AIDS
- Nitrazoxanide (child), Bactrim (SxT)
- resistant to chlorine
Trypanosoma Brucei
- african sleepy sickness
- Tsetse fly (dont fly, sleep at night)
- Tsetse Fly ingests parsite in blood meal-> moves to salivary glands-> inject metacylic trypomastigote into host->PARASITEMIA-> CNS
- sleepy sickness-> invaded CNS
- Antigenic variation
- Winterbottoms sign: lymphadenopathy at base of neck (cervical lymph nodes)
- Nagana (infected cattle)
- ID parasites in blood/lymph/CNS (via LP)
- Suramin (in blood phase only)
- Melarsoprol/DFMO: during sleepy sickness
- DDT, travel at night, remove vegetation
Trypanosoma gambiense
West subspecies
-CNS migration in 1 year-> death in 2-3 years
Trypanosoma rhodesiense
central subspecies
- much more VIRULENT
- CNS migration in 1 month-> death in 6-9 months
- reservoir: antelope
Trypanosoma cruzi
- blood tissue flagella
- Chagas disease (south/central america)
- Triatoma (kissing bug)
- defecate in skin-> human infects self by scratching-> metacyclic trypomastgote-> enter spleen/liver/muscle heart-> transform into amastigote (pseudocyst)
- Romanas sign (swelling around eye)
- acute, chronic phase (10-30years)
- chronis (heart or GI involvement)-> Megacolon megaesophagus
- brain most dangerous, and heart
- Mexico/South central america/ southwest U.S
- serology test done, ID parasite in blood, xenodiagnosis
- benznidazole/nifurttimax (only in blood phase)
- DDT housing, improve living conditions
Leishmania donovani
-tissue flagella
-Sandfly-> takes up amastigotes->promastigote-> injected-> phagocytosed by MQ-> attacks reticuloendothelial cells
-most dangerous one
-sleep, liver, BM affected
-fever, hepato/splenomegaly
-Asia, South America
-reservoir: dogs in Eurasia, latin america
Sodium stibolguconate (toxic)
-amphotericin B, mitefosine
-transmission is aquatic
-ID MQ in blood/tissue
Leishmania tropica/mexicana
CUTANEOUS leishmaniasis (not in blood) papule->skin->ulcer -oriental sore (disfigurement) -African, Mediterranean, southern Asia -mexicana in central america -ID amastigote in skin scrapping Sodium stibolguconate, paromomycin
Leishmania brazilliensis
American Mucocutaneous Leishmania
- primary lesion but secondary ulcerative lesion-> scar (nose is common)
- Mexico, South America
reservoir: Large forest rodents - ID parasite in infected tissue
- Sodium stibolguconate
Toxoplasma gondii
cats
-cat feces-> oocysts
-pseudocysts (raw meat)
-asexually reproduce in humans, immunity in a few wks
symptoms in IC’s
-Congential toxoplasmosis (active infection during pregnancy)
-ingest Bradyzoites in poorly cooked meats, or exposure to cat feces
-ID AB in serology, TSP (toxoplasmosis AB profile)
-do test twice!
Pryimethamine + sulfadiazine, spiramycin (pregnant) to prevent from crossing the placenta
-cook meat thoroughly, if pregnant stay away from cats
Plasmodium spp
Malaria
- mosquitoes
- recurrent chills/fever
- Anemia due to massive RBC destruction and inability to recycle iron
- Western Hemisphere
- humans intermediate host
- only SEXUALLY reproduce in mosquitoes
- Chloroquine (RBC stage, Vivax, m, o)
- Malarone/Quinine sulfate (Chloroquine resistant)
- Primaquine (v/o)-> kills in liver
- Chloroquine phosphate (prophylactic)
- if resistant melfaquine, malarone, doxycycline, artemether (prophylactic)
- airport malaria (N.A., europe)
Plasmodium life cycle
1.) Mosquito injects sporozoites in humans-> liver cells (trophozoites)-> asexual reproduction in liver-> merozoites get into blood stream and attack RBC-> rupture and release more merozoites-> marco and micro gametocytes-> mosquitoes take blood meal-> Okinete formed-> oocysts-> sporozoites go to salivary glands
Plasmodium vivax
benign tertian malaria-> merozoites break out of RBC every 48 hours
-relapse possible from parasite residing in liver for years after
Plasmodium malariae
Quartan malaria: merozoites break out of RBC every 72 hours
NO relapse
plasmodium falciparum
Malignant tertian (95% die)
- NO relapse
- asynchronous release from RBC-> continuous fever
- blackwater fever-> massive BC lysis-> hemoglubin release-> dark urine
- boomerang histology appearance
plasmodium ovale
similar to vivax
