Eukaryotic Pathogens Practice Exam Flashcards

This set of flashcards covers the vocabulary and essential diagnostic/pathological facts for eukaryotic pathogens (parasites and fungi) based on medical faculty exam transcripts.

Echinococcus granulosus

A cestode that causes calcified splenic hydatid cysts and is associated with dogs as definitive hosts and sheep as intermediate hosts.

Diphyllobothrium latum

A tapeworm acquired from raw fish (salmon or trout) that causes intestinal absorption competition leading to vitamin $B_{12}$ deficiency.

Taenia solium

A cestode whose larval stage (Cysticerci) infests undercooked pork; humans can develop cysticercosis through the ingestion of its eggs.

Schistosoma haematobium

A trematode associated with urogenital cancer; its life cycle requires freshwater snails as an intermediate host.

Trichinella spiralis

A nematode causing muscle pain, fever, and periorbital swelling after consumption of undercooked meat containing encysted larvae; diagnosed via muscle biopsy.

Enterobius vermicularis

Commonly known as pinworm, this parasite causes intense nocturnal itching in the perianal area and is diagnosed via the presence of tiny white worms near the anus.

Trypanosoma cruzi

The causative agent of Chagas disease, transmitted through the fecal material of triatomine bugs (kissing bugs) containing metacyclic trypomastigotes.

Trypanosoma brucei

The causative agent of African sleeping sickness transmitted by the tsetse fly; it evades the immune system through antigenic variation of surface glycoproteins.

Plasmodium falciparum

A protozoan species causing severe malaria characterized by merozoites destroying erythrocytes; it can lead to cerebral malaria and is often resistant to chloroquine.

Visceral Leishmaniasis

Also known as Kala-azar, this disease is caused by $Leishmania$ $donovani$ and presents with fever, weight loss, and splenomegaly (enlarged spleen).

Naegleria fowleri

A free-living amoeba found in fresh water that causes acute meningoencephalitis.

Entamoeba histolytica

A protozoan that causes amebic dysentery (bloody diarrhea) and liver abscesses; it utilizes proteolytic enzymes to damage the intestinal mucosa.

Toxoplasma gondii

A parasite transmitted via undercooked meat or cat feces; primary infection during the first trimester of pregnancy poses the highest risk of severe fetal consequences.

Wuchereria bancrofti

A nematode transmitted by mosquitoes that causes lymphatic obstruction, leading to swelling of the lower extremities (elephantiasis).

Ascaris lumbricoides

A large nematode with a life cycle involving ingestion of eggs followed by larval migration through the lungs before maturing in the intestines.

Ancylostoma duodenale

A hookworm that infects humans through skin penetration by larvae (filariform larvae) from contaminated soil.

Cryptococcus neoformans

An encapsulated yeast-like fungus diagnosed using India ink staining to visualize its thick capsule; often associated with pigeon/bird droppings.

Sporothrix schenckii

A dimorphic fungus causing sporotrichosis, characterized by a series of nodules in a linear pattern following a minor scratch from a rose bush.

Aspergillus

A mold characterized by hyphae that branch at an angle of approximately $45^\text{o}$; it can cause allergic reactions and invade blood vessels.

Pneumocystis jirovecii

A fungus that causes bilateral diffuse lung infiltrates in immunocompromised patients (e.g., HIV); it typical does not grow in standard fungal cultures.

Dectin-1

A human immune receptor protein that specifically recognizes fungal $\beta$-glucan.

Amphotericin B

A potent antifungal drug that binds to and extracts ergosterol from membranes; its major clinical adverse effect is nephrotoxicity.

Terbinafine

An antifungal medication that inhibits the enzyme squalene epoxidase, disrupting ergosterol synthesis.

Metronidazole

An antimicrobial drug used to treat infections from anaerobic bacteria and protozoa like $Giardia$ $lamblia$, $Trichomonas$ $vaginalis$, and $Entamoeba$ $histolytica$.

Praziquantel

The primary drug used for treating infections caused by trematodes ($Schistosoma$) and certain cestodes ($Taenia$).

Conidia

The asexual spores formed by various fungi for reproduction and dispersal.

Tinea Nigra

A superficial fungal infection typically caused by $Hortaea$ $werneckii$, presenting as dark lesions on the palms of the hands.

Piedraia hortae

The causative agent of Black Piedra, a fungal infection of the hair scalp.