Eukaryotic Cells (Eukaryotic Pathogens) Flashcards
Define Hapha (singular)/ Haphae (plural)
-long filaments on cells in a mold
What is the function of a hapha?
-Releases digestive enzymes to digest their surroundings and absorb nutrients by diffusion
What are the most common Fungi that can aspergillosis (2)?
Most common:
- Aspergillus Fumigatus
- A. Flavin
Rare:
-A. Terreus
Locations/work that increase the opportunity to infect immunocompetent people with Aspergillosis
-construction, agriculture, hospital renovation (repeated exposure everyday)
Aspergillosis may go systemic (invasive) in what kind of patient?
-immunocompromised patient
How is aspergillosis commonly transmitted?
What are the common locations of contraction?
- inhalation of spores
- Construction, agriculture, hospital renovation
What is used to treat Aspergillosis?
-antifungal medications
Pre existing medical conditions that increase opportunity to infect immunocompetant people with Aspergillosis
- asthma
- cystic fibrosis
What is the case fatality rate of systemic aspergillosis in Immunocompromised Patients?
40-75%
Explain how Aspergillosis can be fatal to a patient with HIV?
1) The mold invades body becoming systemic
2) Gets into the bloodstream
3) Damages deep layers of skin
4) Gets into the bone, brain, and nervous system
How can Aspergillosis be dangerous in a hospital environment?
- molds can grow in the walls of a hospital, and is not revealed until renovation
- renovation can spread the spores in the air of the hospital
- hospital is filled with immunocompromised patients, and spreading the spores is dangerous
What are the species that cause intestinal Amebiasis?
- Entamoeba Hitolytica
- E. Diaper
- E. Moshkovskii
What is the ratio and percentage of symptomatic vs asymptomatic infections of Amebiasis?
- 1:5
- 20% symptomatic, 80& asymptomatic
How does Amebiasis present itself under a symptomatic infection?
- Diarrhea; can be bloody (dysentery)=amoebic dysentery (extreme case)
- Rare:liver abscesses,lung/heart abscesses
Greatest risk for contracting amebiasis worldwide vs US
-Countries with poor water treatment systems
-US: less common; community transmission through fecal-oral transmission
Risk group: men who have sex with men
How is amebiasis transmitted?
- fecal oral transmission
- parasite only loves in humans and is passes in the feces of an infected person
How is amebiasis prevented?
-Public health measures:
Water treatment Cook food thoroughly Wash hands frequently Use of appropriate barriers during sexual contact
How is amebiasis treated?
-antiprotozoal medications
What are the characteristics of a entamoeba cyst
- (most infectious form)
- dormant/ no phagocytosis
- does not eat RBC/ not getting nutrients
- does not reproduce
- durable:resistant to dehydration
What are the characteristics of a Trophozoite?
- performs phagocytosis
- reproduces
- found in intestines, liver, heart, lungs
What is the most common worm infection (enterobiasis) in the US?
-Enterobius Vermicularis (Pinworm)
What is the ratio of people infected with enterobius vermicularis in the US
-1/8 people; 40 million
Who are the most common people infected with Enterobius Vermicularis
-preschool and school aged children
What are the signs/symptoms of enterobius vermicularis (pinworm)?
- usually asymptomatic
- can cause itchiness of the anus
- Rare cases: anorexia, abdominal pain, disrupted sleep
What is a granuloma?
-formed when immune cells clump together and create tiny nodules at the site of infection or inflammation
How is enterobius vermicularis transmitted?
-fecal-oral transmission, usually through objects contaminated with E. Vermicularis ova/fecal matter
What are the different ways to diagnose Enterobius Vermicularis?
1) directly observe the anus of a child about 1-2 hours after they fall asleep
2) Preferred: to take a specimen in the morning using some adhesive tape and observing through a microscope
Describe the life cycle of Enterobius Vermicularis
1) Human injects pinworm eggs
2) in the small intestine, larvae hatch and grow (after 30 days)
3) female worms migrate to the anus, where they release their eggs (worms live 60 days)
4) scratching of irritated anus promotes egg transmission to new host
How is enterobius vermicularis treated?
-antihelminthic medications
What are the 2 different types of tapeworms?
- Tania Solium = Pork tapeworm
- T. Saginata = beef tapeworm
How does one get infected with Taeniasis (tapeworm)?
-eating undercooked pork/beef containing cysticerci (encysted worms in muscle tissue)
Describe the structure of a Taenia Tapeworm
- usually 5m long, but can grow up to 25m (can cause bowel obstruction)
- Scolex: head of tape worm, embeds in the intestinal wall
- proglottid: repeating segments that make up the majority of the tapeworm. Each one is full of reproductive organs (makes ova and sperm)
Explain what happens to the proglottids at the tail end of the tapeworm
-proglottids either disintegrate and release their fertilized eggs, or the entire proglottis just detaches and then the eggs and or proglottids are released in the fecal matter
What are the symptoms of Taeniasis (tapeworm)?
- usually asymptomatic
- when present: abdominal pain, loss of appetite, weight loss, upset stomach
- proglottids visible in feces
How can one contract cysticercosis?
- Consumption of embryonic eggs in contaminated food or by autoinfection.
- the embryonic eggs hatch, release oncospheres, which can migrate to the muscle and or other tissues forming cysticerci.
What can help prevent the growth of cysticerci? What is the disadvantage of this treatment?
-using antihelminthic medications;
may worsen symptoms due to immune response (steroids fighting inflammation)
