Infectious Disease: Fungi, Protozoa, Parasites

yeast

unicellular & proliferate by budding

mycelium

mold, formed by hyphae network

fungal meningitis

occurs when contaminated steroids were used for spinal and eye infections

ringworm, jock itch, athlete’s foot, scalp infection, nail infection

what are examples of dermatophytes?

skin and nails

soil fungus or fusarium often infects what?

fusarium

can lead to keratitis and corneal ulcerations, dark spot in the middle where the fungi are making spores and spores are resistant to treatment

ReNu MoistureLoc

solution that increased fungi growth and was recalled

candida albicans

in immunocompromised individuals, overgrowth can lead to oral thrush, yeast infections, diaper rash, and GI candidiasis

itchiness

what is a common side effect of fungal infections?

culture or KOH

fungal infections are diagnosed with what?

CL wear, surgery, trauma due to vegetative matter

what can cause corneal fungal infections?

natamycin, voriconazole

what do you treat corneal fungal infections with?

no

can you use antibiotics and steroids to treat fungal infections?

histoplasmosis

• asymptomatic to flu-like in normal people

• fatal systemic illness in immunocompromised people

• results in lung infection and chorioretinitis

• fungi spread by birds and bats

presumed ocular histoplasmosis syndrome

• causes chorioretinal scars (punched out lesions)

• peripapillary atrophy

• lesions can reactivate and lead to choroidal neovascularization and areas of scarring

protozoal diseases

can infect most areas of the body and most are diagnosed by microscopic examination of blood smears or lesions

malaria

caused by plasmodium, highly prevalent

sporozoite in salivary glands of female mosquitos transmitted by bite

what is the first stage of malaria infection?

invade liver cells and multiply

what is the second stage of malaria infection?

liver cells rupture and release merozoites

what is the third stage of malaria infection?

invade RBCs and hydrolyze hemoglobin

what is the fourth stage of malaria infections?

release from dying RBCs releases cytokines causing chills and fever

what is the fifth stage of malaria infection?

protozoa releasing en masse from RBCs

what causes the immune response in malaria?

yes if not treated

can malaria recur?

P falciparium

causes RBCs to stick to vascular endothelial cells causing infarctions and ischemia responsible for cerebral malaria

RBCs

mutations affecting _____ are highly prevalent in parts of the world where malaria is endemic

blood smear, microscopy

what is used to diagnose malaria?

artemisinins and other anti-malarials

what is the treatment for malaria?

T cruzi

what bacteria causes chagas?

chagas

• caused by kissing bugs that are attracted to mucous membranes (eyes, nose, mouth)

• more common in rural Southern areas

• bug droppings transmit disease

• bite may leave an erythematous nodule (red bump)

acute eyelid swelling

sign of infection of chagas

phagolysosome

T. cruzi requires acidic environment of ___________for life cycle

20-30%

what percentage of people develop debilitating, life threatening illnesses from chagas?

acanthamoeba

• common soil/water amoeba

• free living and encysted phases

• infections: keratitis, encephalitis

• associated with CL wear

• eye infections can look bacterial

no

do antibiotics and steroids help treat amoebas?

ring or dendritic ulcers

acanthamoeba causes what in the cornea?

E coli

what is the acanthamoeba’s favorite food?

biofilm

acanthamoebas can feed on the ______ in CL case and proliferate

complete moisture plus

CL solution that caused an acanthamoeba outbreak

toxoplasmosis

• humans are infected with this by eating infected meat or changing kitty litter

• normal adult infection is asymptomatic of flu-like symptoms

• infants can be born with infection causing TORCH lesions/cysts

• cysts in the eye can cause chorioretinitis

pediculosis

infections by lice

phthirus pubis (pubic louse)

infects pubic regions, armpits, eyelashes, eyebrows, beard, mustache, and chest and back hair; typically transmitted by sexual contact

pick them out and drop into alcohol

how do you treat pubic lice in the eyelashes?

bedbugs

• hide in bedding & cracks

• can live for a year w/o feeding

• normally feed every 5-10days

• pierce host with stylet and suck blood leaving itchy welts

MRSA

what can bed bug bites get infected with?

heat

what is the treatment for bedbugs?