Page 202 - First Aid for the USMLE Step 1 2020, Thirtieth edition [MedicalBooksVN.com]_Neat

158 SEcTioN ii Microbiology ` microbiology—Parasitology Microbiology ` microbiology—Parasitology

Protozoa—others
orgaNism Disease traNsmissioN DiagNosis treatmeNt
Visceral infections
Trypanosoma Chagas disease—dilated Triatomine insect Trypomastigote in Benznidazole
cruzi cardiomyopathy with (kissing bug) bites blood smear A or nifurtimox;
apical atrophy, megacolon, and defecates cruzing in my
megaesophagus; predominantly around the mouth Benz, with a fur
in South America or eyes; fecal coat on
Unilateral periorbital swelling transmission into
(Romaña sign) characteristic of bite site or mucosa
acute stage
Leishmania spp Visceral leishmaniasis Sandfly Macrophages Amphotericin B,
(kala-azar)—spiking fevers, containing sodium
hepatosplenomegaly, amastigotes C stibogluconate
pancytopenia
Cutaneous leishmaniasis—skin
ulcers B
Sexually transmitted infections
Trichomonas Vaginitis—foul-smelling, greenish Sexual (cannot exist Trophozoites (motile) Metronidazole for
vaginalis discharge; itching and burning; outside human D on wet mount; patient and partner
do not confuse with Gardnerella because it cannot punctate cervical (prophylaxis; check
vaginalis, a gram-variable form cysts) hemorrhages for STI)
bacterium associated with (“strawberry
bacterial vaginosis cervix”)
A B C D

Nematode routes of Ingested—Enterobius, Ascaris, Toxocara, You’ll get sick if you EATTT these!
infection Trichinella, Trichuris
Cutaneous—Strongyloides, Ancylostoma, These get into your feet from the SANd
Necator
Bites—Loa loa, Onchocerca volvulus, Lay LOW to avoid getting bitten
Wuchereria bancrofti

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