Protozoa Flashcards
describe protozoa
single-celled eukaryotic organisms
What is the STD parasite
Trichomonas Vaginalis
how do you dx trichomonas vaginalis
PCR + trophozoite in discharge
What is the tx for trichomonas vaginalis
metronidazole for pt & partner
What is the life cycle of trichomonas vaginalis
human genital tract–> REPLICATES BY BINARY FISION –> transmitted via sexual contact
frothy greenish discharge
T. vaginalis
Strawberry cervix
T. vaginalis
Twitching trophozite
T. vaginalis
on microscopy you see a trophozoite w/ undulating membrane, 4 anterior flagella and single nucleus
T. vaginalis
MC cause of Amebic dysentary
Entamoeba Histolytica
How do you dx Entamoeba Histolytica
Cysts in stool, serology, Ameba antigen + PCR
How do you tx Entamoeba histolytica
Metronidazole (but doesn’t clear it)
Life cycle of Entamoeba histolytica
fecal-oral –> excitation back to trophozoite in small intestine –> migrate to large intestine
what are the 3 types of presentations for entamoeba histolytica and how do they present
- Asyptomatic: trophozoites produce cysts that live outside the body
- Intestinal dz: “flask shaped” abscesses in L intestine –> bloody dysentary
- Liver dz: gets to portal circulation –> liver abscesses w/ anchovy paste aspirate
anchove paste aspirate in liver
Entamoeba histolytica (w/ liver dz)
Flask shaped ulcers in intestine
Entamoeba histolytica (w/ intestinal dz)
rounded elevated mucosa of intestine w/ necrotic centers and edematous tissue
describes flask shaped ulcers in Entamoeba histolytica
on microscopy you see a single nucleus trophozoite w/ ingested RBC
Entamoeba histolytica
You suspect a parasite and the pt has RUQ pain and dysentary
Entamoeba histolytica
What are the 3 parasites that cause intestinal issues
Entamoeba histolytica, Giardia lamblia, & Cryptosporidium
daycare worker w/ low nutrients, uncontrollable flatulence, bloating, foul-smelling steatorrhea
Giardia lamblia
Camper w/ low nutrients, uncontrollable flatulence, bloating, foul-smelling steatorrhea
Giardia lamblia
Life cycle of giardia?
cysts in water ingested by camper –> trophozoite multiply by BINARY FISION –> excitation –> move to colon and cover and flatten intestinal epithelium (no absorption -> diarrhea)
on microscopy you see a trophozoite w/ 2 nuclei, symmetrical axostyles, & suction discs
Giardia lamblia
on microscopy you see a cyst w/ 4 nuclei and a well defined wall
Giardia lamblia
how do you dx giardia lamblia
symptoms + cysts/trophs in stool
how do you tx giardia
metronidazole
What do you think of when you hear someone gets sick after swimming at a waterpark or reservoir
Cryptosporidium
who is most likely to get infected with cryptosporidium
the IC
What would an HIV pt w/ cryptosporidium present w/
ascending cholangitis
Milwalkee
cryptosporidium
How do you dx cryptosporidium
Serology
how do you tx cryptosporidium
Nitazoxanide
what is the life cycle of cryptosporidium
infectious oocyst releases sporozoites into gastric epithelium which differentiate into merozoites (asexually). these differentiate into gametes which fuze into a zygote which make oocysts
Acid fast oocyst
cryptosporidium
IC pt w/ watery diarrhea +/- gallbladder, biliary tract, & lung dz
Cryptosporidium
how do you estimate the severity of cryptosporidium infection in an immunocompetent pt
ingested oocysts correlates w/ severity of diarrhea
how do you dx toxoplasma gondii infection
serology
CT for congenital toxoplasmosis
what is the tx for toxoplasma gondii
Sulfadiazine + Pyrimethamine
what is the definite host of toxoplasma gondii
cat
what is the intermediate host of toxoplasma gondii
human
what is the life cycle of toxoplasma gondii
sexually divides in cats –> injest cysts from UNCOOKED MEAT & CAT FECES
ring enhancing lesions (brain abscess)
HIV pt w/ toxoplasma gondii
chorioretinitis, hydrocephalus, & intracranial calcifications
classic triad for congenital toxoplasmosis
acute rapid deterioration w/in 1 week of swimming in fresh water
Naegleria Fowleri
what is the most rapidly fatal cause of meningoencephalitis
Naegleria Fowleri
how do you dx Naegleria Fowleri
amoebas in CSF
Nedipots
Naegleria Fowleri
Divers
Naegleria Fowleri
what is the life cycle of Naegleria Fowleri
swimming then the flagellated form enters via cribriform plate to brain
primary amebic meningoencephalitis
Naegleria Fowleri
suspect bacterial CSF (dec glu, inc protein, inc PMN), but does not gram stain
Naegleria Fowleri
Eye infection w/ someone who wears contacts
Acanthamoeba Keratitis
what is the tx for Acanthamoeba Keratitis
topical Rx + steroids
if someone has a bacterial infection of the eye and still wears contacts
Acanthamoeba Keratitis
what 2 forms of Tyrpanosoma Brucei are there and what location in the world are they associated w/
Gambiense (w. africa)
Rhodensiense (E. africa)
how do you dx Tyrpanosoma Brucei
card agglutination test
what is the tx for Tyrpanosoma Brucei
Blood stage: Suramin
CNS stage: Melarsoprol
Tsetse fly
Tyrpanosoma Brucei
Life cycle of Tyrpanosoma Brucei
tsetse fly bite –> trypomastigote spread in blood to lymph nodes + CNS
How does Tyrpanosoma Brucei become a recurrent problem
Antigenic variation (variable surface GPs)
what would you see on microscopy if infected w/ Tyrpanosoma Brucei
trypomastigote w/ kinetoplast + UNDULATING MEMBRANE
Chancre that heals in 2 wks, then develop LAD & fever, eventually causing coma and death
Tyrpanosoma Brucei
what is the hallmark of african sleeping sickness
Encephalitis
person in south america
Chagas dz T cruzi
What bug causes chagas
Reduviid bug
Life cycle of T cruzi
feeds on humans while sleeping, defecates while eating (releases Trypomastigotes) –> penetrates skin (forms chagoma) –> transform into amastigote –> replicate and infect
Unilateral facial swelling @ bite site
T cruzi (chagas)
Damage to nerve ganglia causing dilated cardiomyopathy, megacolon, and megaesophagus
T cruzi (chagas)
What are the 3 leishmania bugs and what do they cause
L. Donovani - visceral
L Braziliensis - mucocutaneous
L. Tropica - cutaneous
Veteran from afghanistan
Leishmania
How do you dx leishmania
serology and protozoa in liver/spleen
how do you tx leishmania
Sodium Sibogluconate
Life cycle of leishmania
Sand fly bites host –> Promastigote invades MACROPHAGE –> transforms into non-motile amastigote in RES system
ulcer @ site of infection that is self limiting
Cutaneous leishmania (L donovani)
ulcers lead to erosion of nasal septum palate and lips (mucoid tissue)
mucocutanious leishmania (L braziliensis)
Hepatomegaly, massive splenomegaly w/ pancytopenia
Kala Azar (visceral leishmania - L tropica)
How do you dx malaria
geimsa smear + immunochromatograph
cyclic Fever w/ chills and anemia, headache, splenomegaly
malaria
What is the worst form of malaria
falciparum
patient from thailand
mefloquine resistant malaria
Life cycle of Plasmodium
Anopheles mosquito injects sporozoites when feeding –> makes way to liver (start of pre-erythrocytic cycle)–> forms trophozoite which divides into thousands of schizonts and make merozoites which are released when the cell bursts–> infect RBC Merozoites become gametes and can be picked up with mosquito bite
fever on 1st and 3rd day
Vivax/ovale
fever on 1st and 4th day
Malariae
irregular pattern of fever btw 36-48 hrs
falciparum
what is a major feature of infected RBCs in falciparum malaria
Rosetting
What carries babesia
Ixodes tick (same as lyme dz)
on peripheral smear you see a maltese cross
babesia
Most commonly seen in NE USA
Babesia
fever, hemolytic anemia, asplenia
babesia
what is the tx for babesia
quinine, clindamycin