NURS 236 ~ Fungal, Protozoal, and Helminth Infections of Humans

what are helminths

parasitic worms

how can helminths be classified

Macroscopic, multicellular, eukaryotic organisms

what is the life cycle of a helminth

Eggs, larvae, adult worms (each can serve as the infective stage for different helminths)

what are the three classifications of helminths

nematodes, cestodes, trematodes

which forms of worms are nematodes

roundworms

which forms of worms are cestodes

tapeworms

which forms of worms are trematodes

flukes

which helminths are flat worms

cestodes and trematodes

ascaris lumbricoides and wuhereria bancrofti are examples of which helminths

nematodes

taenia saginata and taenia solium are examples of which helminths

cestodes

Schistosoma haematobium and Fasciola hepatica are examples of which helminths

trematodes

which pathogen causes ascariasis

ascaris lumbricoides

what are clinical features of ascariasis

Abdominal discomfort, intestinal obstruction, growth impairment in children

what is the mode of transmission for ascariasis

Fecal-oral route, ingestion of contaminated food or water

what are risk factors of ascariasis

Poor personal hygiene, inadequate sanitation, consuming unwashed fruits and vegetables

A 7-year-old child from a rural community is brought to the clinic with worsening abdominal discomfort and poor appetite. His mother reports he frequently plays outside barefoot and often eats fruit picked straight from the garden without washing it. Imaging reveals intestinal obstruction caused by large parasitic worms. what might this patient be experiencing?

ascariasis

which pathogen causes filariasis

Wuchereria bancrofti

what are the clinical features of filariasis

Severe lymphedema of the limbs (due to the lodging of worms in lymphatic vessels) and fibrosis of the skin

What is the mode of transmission of filariasis

Bite of infected mosquitoes in the genera Culex, Anopheles, or Aedes

What are risk factors for filariasis

Inadequate sanitation, residing close to stagnant water bodies (e.g. ponds, marshes)

filariasis is charachterized by what

swelling of the lower limbs and thickening of the skin

what is elephantiasis

the swelling of the lower limbs and thickening of the skin due to filariasis

what pathogens cause taeniasis

Taenia saginata (beef tapeworm),

Taenia solium (pork tapeworm)

A 42-year-old man living in a rural region near stagnant marshes presents with progressive swelling of his lower legs, leading to thickened, fibrotic skin that makes walking difficult. He reports many mosquito bites, especially at night, and his village has limited sanitation. What parasitic infection might be causing this?

filariasis

what are clinical features of taeniasis

while mostly asymptomatic, some pts experience abdominal discomfort as well as a loss of appetite

what is the mode of transmission for taeniasis

The ingestion of raw or undercooked beef or pork

contaminated with human feces

What are risk factors for taeniasis

Poor personal hygiene, inadequate sanitation

What pathogen causes schistosomiasis

Schistosoma haematobium (blood fluke)

What are the clinical features of schistosomiasis

Fever, malaise, abdominal pain, dysentery, ascites (due to portal hypertension in some cases)

What is the mode of transmission for schistosomiasis

Penetration of the skin after coming into contact with contaminated freshwater

What are the risk factors for schistosomiasis

Bathing or swimming in contaminated freshwater

A 29-year-old man presents to the clinic with vague abdominal discomfort and decreased appetite. He reports that he recently attended a cultural festival where he ate raw beef dishes and admits that food hygiene at the event "didn't look great." Given his symptoms and exposure history, what parasitic infection should be suspected?

taeniasis

A 12-year-old boy from a rural village presents with fever, malaise, abdominal pain, and new-onset distended abdomen. His mother reports that he swims daily in a nearby freshwater pond where other children play. Labs later show signs consistent with portal hypertension, and stool testing reveals characteristic ova. what might you as the nurse suspect him experiencing?

schistosomiasis

what pathogen causes fascioliasis

Fasciola hepatica (liver fluke)

what are clinical features of fascioliasis

Fever, malaise, abdominal pain, diarrhea, inflammation of the liver, gallbladder, and hepatobiliary tree

What is the mode of transmission for Fascioliasis

Ingestion of contaminated food (especially raw watercress) or water

what are risk factors for facioliasis

Inadequate sanitation, consuming unwashed aquatic plants or salad vegetables

A 32-year-old woman presents with fever, malaise, and persistent right-upper-quadrant abdominal pain. She reports frequent diarrhea and recently began eating raw watercress from a local farm. Imaging shows inflammation of the liver and biliary tract. which parasitic infection might this kid have?

fascioliasis

what is the pathogen for african trypanosomiasis

trypanosoma brucei

what is the alternative name for african trypanosomiasis

african sleeping sickness

what are the early stage clinical features of african trypanosomiasis

fever, headache, myalgia

what are the late stage clinical features of African trypanosomiasis

Reversal of the normal sleep-wake cycle as the protozoan crosses the blood-brain barrier and affects the sleep centers in the hypothalamus

what is the mode of transmission for african trypanosomiasis

the bite of an infected tsetse fly

what is the pathogen for american trypanosomiasis

trypanosoma cruzi

What is the alternative name for American Trypanosomiasis

chagas

what are the early stage clinical features of american trypanosomiasis

fever, headache, myalgia

what are the late stage clinical features of american trypanosomiasis

Cardiac complications (e.g. arrhythmias) and GI involvement (e.g. dysphagia, constipation)

what is the mode of transmission for american trypanosomiasis

the bite of an infected triatomine bug(the kissing bug) followed by the defecation into the wound

what is a common sign found in pts with american trypanosomiasis

romands sign

what is romands sign

Unilateral eyelid and periorbital edema (following the accidental rubbing of bug feces into the eye) is an early sign

what pathogen causes malaria

multiple protozoan species in the genus plasmodium

which pathogens cause tertian malaria

P. vivax, P. ovale, P. falciparum

which pathogen cause quartan malaria

P. malariae

what are the clinical features of malaria

Fever, chills, sweating, headache, nausea and vomiting

which malaria causing pathogen can result in liver and kidney failure, pulmonary and cerebral edema, coma, and death

p. falciparum

what means of locomotion does malaria have

none

what are the reservoirs of malaria

human and miquitoes

what is the mode of transmission for malaria

the bite of an infected female anopheles mosquito

A 26-year-old woman returns from a humanitarian trip to West Africa and develops fever, chills, and intense sweating every 48 hours. Over the next few days, she becomes progressively more ill, with severe headache, nausea, and episodes of confusion. Her blood smear shows intracellular parasites consistent with what

tertian malaria

A 34-year-old man who recently traveled to rural South America presents with recurrent fevers occurring every 72 hours, accompanied by chills, vomiting, and malaise. He reports that the pattern has been consistent and predictable for over a week. Microscopic analysis of his blood reveals which type of infection?

quartan malaria

what pathogens cause amebiasis

entamoeba histolytia

what are the clinical features of amebiasis

Fever, nausea, vomiting, abdominal pain, diarrhea or

dysentery, Amebic abscesses may develop in the liver, and Amebomas may develop in the colon

what are the key features of amebiasis

Amebic abscesses may develop in the liver, and Amebomas may develop in the colon

what is the mode of transmission for amebiasis and balantidiasis

fecal-oral route, ingestion of contaminated food or water

how do amebae move

pseudopods aka false feet

A 32-year-old man returns from a trip where he frequently ate street food and drank untreated water. He now presents with fever, abdominal pain, nausea, and episodes of bloody diarrhea; imaging later reveals a solitary liver abscess. Which parasitic infection best explains his symptoms?

amebiasis

what is the pathogen for balantidiasis

balantidium coli

what are the clinical features of balantidiasis

Fever, nausea, vomiting, abdominal pain, diarrhea or dysentery

which individuals are more likely to experience signs and symptoms of balantisiasis

those who are immunocompromised

What is the reservoir for Balantidiasis`

pigs

how do ciliates in balantidiasis move

by means of hair-like projections

what is the pathogen for giardiasis

gardia lamblia

what are the clinical features of giardiasis

Fever, nausea, vomiting, abdominal pain, diarrhea or dysentery

which type of stool is commonly found in individuals with giardiasis

steatorrhea

how do flagellates travel in individuals with giardiasis

by means of whip-like flagella

A 7-year-old girl returns from summer camp with fever, abdominal pain, and several days of foul-smelling, bulky, yellow-gray diarrhea that floats in the toilet. Her mother reports the child drank water from a stream during a hike. What parasitic infection is the most likely cause of her symptoms?

giardiasis

what pathogen causes trichomoniasis

Trichomonas vaginalis

what are the clinical features of trichomoniasis in women

Inflammation of the vagina and cervix, characterized by itching or burning

what are the clinical features of trichomoniasis in men

burning during urination or after jactulation

what might the discharge characteristics of a female patient experiencing trichomoniasis

greenish-yellow discharge that appears to be frothy or foamy

what is the mode of trichomoniasis

person to person by sexual contact

A 26-year-old woman comes to the clinic with vaginal itching, burning, and a frothy, greenish-yellow discharge with an unpleasant smell. She recently became sexually active with a new partner and has no history of yeast infections. Pelvic exam confirms inflammation of the vaginal walls and cervix.

trichomoniasis

A 30-year-old man reports burning during urination and mild discomfort after ejaculation. He denies penile ulcers or testicular pain. His partner was recently diagnosed with a sexually transmitted infection. Urinalysis is negative for bacteria.What infection is most likely causing his symptoms?

trichomoniasis

what is a characteristic sign of trichomoniasis found on woman's cervix's

capillary hemorrhages(strawberry cervix)

what is a protozoa

eukaryotic, non-photosynthetic organism found in soil and water

what is the trophozoites stage of protozoa

motile, feeding, and dividing stage, rarely serves as the infective stage

what is the cyst, oocytes, and spore stage of protozoa

non-motile dormant, survival stages, serves as the infective stage

how are protozoa infections diagnosed

via microscopic examination of body fluids, tissues, or feces

what pathogen causes cutaneous leishmaniasis

leishmania donovani

what are the clinical features of cutaneous leishmaniasis

it starts as a papule that enlarges into a crater-like ulcer, that can coalesce, causing tissue destruction and sever disfunction

what is the reservoir for cutaneous leishmaniasis

humans, dogs, and wild animals

what is the mode of transmission for cutaneous leishmaniasis

the bite of an infected sand fly

A 26-year-old man returns from a recent trip to rural Brazil and reports that a small papule on his forearm has gradually enlarged into a painful, crater-like ulcer. He now has multiple coalescing ulcers with significant tissue destruction. He mentions being bitten repeatedly by sand flies during evening hikes. what might he be experiencing?

cutaneous leishmaniasis

where can protozoan cells from cutaneous leishmaniasis spread from an initial skin lesion

liver, spleen, and bone marrow

what can occur if leishmania donovani spreads to the liver, spleen, and bone marrow via the bloodstream

visceral leishmaniasis or kala-azar

which pathogen causes acanthamoeba keratitis

multiple protozoan species in the genus Acanthamoeba

what are clinical features of acanthamoeba keratitis

inflammation of the cornea, charachterized by severe pain, pus formation, and scarring

what are the reservoirs for acanthamoeba keratitis

water bodies such as pools and tanks

what is the mode of transmission of acanthamoeba keratitis

swimming in contaminated water or wearing improperly disinfected contact lensed

what is the incidence in the US for Acanthamoeba keratitis

1-2 cases per million contact lens users annually