Other Helminths, Protozoa, and Fungi Info Flashcards
Blastomyces dermatitidis (True Pathogen Fungi)
Pulmonary blastomycosis -
Most common manifestation
Initial pulmonary lesions are mostly asymptomatic
When symptoms occur they are nonspecific
The disease typically resolves but may become chronic
Cutaneous blastomycosis -
Painless lesions on the face and upper body
Osteoarticular blastomycosis -
Spread of the fungus to the spine, pelvis, cranium, ribs, long bones, or subcutaneous tissues surrounding joints
Meningitis -
Dissemination of the fungus to the central nervous system
Can occur in AIDS patients
Diagnosis based on identification of fungi in culture or samples
Paracoccidioides brasiliensis (True Pathogen Fungi)
Infection begins as a pulmonary condition
The fungus can spread and create lesions
Diagnosis based on the presence of yeast in a “steering wheel” formation in patient samples
Aspergillosis (Oppurtunistic Fungi)
Hypersensitivity aspergillosis -
Manifests as asthma or other allergic symptoms
Noninvasive aspergillomas -
Masses of fungal hyphae form in the cavities following pulmonary tuberculosis
Acute invasive pulmonary aspergillosis -
May present as pneumonia
Cutaneous and systemic aspergillosis also occur
Pneumocystis Pneumonia (Opportunistic fungi)
Pneumocystis jiroveci
Transmission most likely occurs through inhalation
Infection in immunocompetent is usually asymptomatic
Common opportunistic fungal infection of AIDS patients
Presence of the disease is almost diagnostic for AIDS
Can result in death if left untreated
Diagnosed based on clinical and microscopic findings
Cryptococcus neoformans (Opportunistic Pathogen Fungi)
Cryptococcus neoformans gattii -
Infects immunocompetent individuals
Cryptococcus neoformans neoformans -
Infects AIDS patients
Results from inhalation of spores or dried yeast in bird droppings
Various diseases can result from infection -
Primary pulmonary cryptococcus -
Asymptomatic or mild pneumonia
Cryptococcal meningitis -
Most common clinical form of cryptococcal infection
Follows dissemination of the fungus to the CNS
Cryptococcoma -
Rare condition in which solid fungal masses can form
Cutaneous cryptococcosis -
Skin lesions or inflammation of subcutaneous tissues
Dermatophytes
Tinea pedis (“athlete’s foot”)
Tinea cruris (“jock itch”)
Tinea unguium (onychomycosis) -
Superficial white onychomycosis: patches or pits on the nail surface
Invasive onychomycosis: yellowing and thickening of the distal nail plate, often leading to loss of the nail
Tinea capitis -
Ectothrix invasion: fungus develops arthroconidia on the outside of the hair shafts, destroying the cuticle
Endothrix invasion: fungus develops arthroconidia inside the hair shaft without destruction
Favus: crusts form on the scalp, with associated hair loss
Taenia saginata (Cestodes Helminth)
the beef tapeworm (cattle are intermediate host)
Echinococcus granulosus (Cestodes helminth)
Canine tapeworm
Humans are accidental intermediate hosts
Consume food or water contaminated from dog feces
Causes hydatid disease
Larvae travel throughout body and form hydatid cysts
Symptoms follow enlargement of cysts in infected tissue
Diagnose by immunoassay and visualization of cysts
Fasciola hepatica and Fasciola gigantica
(Trematodes)
Infect sheep and cattle worldwide
Humans are accidental definitive hosts
Ingest metacercariae from aquatic vegetation
Chronic infections occur when flukes reside in the bile ducts
Symptoms coincide with episodes of bile duct obstruction and inflammation
Diagnosis based on presence of eggs in feces, and symptoms
Trematodes - Schistosoma
S. mansoni
S. haematobium
Ancylostoma duodenale (Nematodes)
Same info as Necator americanus
Anisakis simplex (Nematodes)
Humans are accidental host
Infected by consuming raw or undercooked fish
Infections are typically asymptomatic
Some individuals develop allergies to the worms
Diagnosis based on endoscopic identification of worms in the intestine
Dermacentor andersoni
a wood tick
Sarcoptes scabeii
Mite
Pediculus humanus capitis
head lice
Phthirus pubus
pubic louse
Aedes mosquito
Ctentocephalidis canis
a flea
Musca domestica
a housefly, which can carry microbes on its body
Balantidium coli (Ciliates)
Humans infected by food or water contaminated with feces containing cysts
Trophozoites attach to mucosal epithelium lining the intestine
Infections generally asymptomatic in healthy adults
Balantidiasis occurs in those with poor health
Persistent diarrhea, abdominal pain, and weight loss
Severe infections may produce dysentery and ulceration of the intestinal mucosa
Presence of trophozoites in stool is diagnostic for the disease
Entamoeba histolytica (amoebae)
Carried asymptomatically in the digestive tracts of humans
Infection most commonly occurs by drinking contaminated water
Excystment occurs in the small intestine
Trophozoites migrate to the large intestine
Luminal amebiasis -
Asymptomatic infections in healthy individuals
Invasive amebic dysentery -
Severe diarrhea, colitis, appendicitis, and ulceration of the intestinal mucosa
Invasive extraintestinal amebiasis -
Trophozoites in the blood are carried through the body
Acanthamoeba (Amoebae)
Enters through cuts, scrapes, the conjunctiva, or inhalation
Keratitis occurs when trophozoites invade the eye
Amebic encephalitis is the more common disease
Causes headache, altered mental state, neurological defects, and eventually death
T. brucei rhodesiense (flagellates)
Strain
Leishmania (flagellates)
Cutaneous leishmaniasis -
Large painless skin ulcers form at the bite wounds
Mucocutaneous leishmaniasis -
Skin lesions enlarge to encompass mucous membranes of the mouth, nose, or soft palate
Visceral leishmaniasis -
Macrophages carry the parasite to the liver, spleen, bone marrow, and lymph nodes * Fatal in 95% of untreated cases
Diagnosis through skin scraping
Apicomplexans of Plasmodium
P. vivax
P. ovale
P. malariae
P. knowlesi
Cryptosporidium parvum (apicomplexan)
Humans can carry the parasite asymptomatically
Infection usually results from drinking contaminated water
Fecal-oral transmission can occur
Causes severe diarrhea accompanied by headache, muscle pain, cramping, and fluid and weight loss
Many diagnostic techniques cannot detect Cryptosporidium
Oocysts detected by microscopic examination or use of fluorescent-labeled antibodies
Cyclospora cayetanensis (Apicomplexans)
Infection occurs from ingesting contaminated food or water
Outbreaks linked to raspberries from Central and South America
