Pneumocystis carinii

Kelly Rueckert and Melissa Greco

This parasite/Fungus is commoneverywhere in theworld.

Geographic Distribution

It is considered a fungus, but is mentioned in our book because it is considered a opportunistic parasite that often causes severe pathology and is very dangerous to HIV patients.

It may have fungal properties but is sensitive to protozoan agents.

Ribosomal RNA sequence shows Pneumocystis carinii to be a member of the Fungi

Developing from a small trophozoite into a cyst containing eight sporozoites, the Pneumocystis carinii life cycle superficially resembles those seen both in protozoa and fungi

Fungus or Parasite?

Life Cycle of the Pneumocystis Carinii

A slide of Pneumocystis carinii

Humans of all ages, and especially prelavant in elderly and in small children with weaker immune systems

Also seen in people taking drugs to cure autoimmune disease

Persons with AIDS are especially susceptible.

This organism is wide spread in mammals, many infections may be caught from pets.

Definitive Hosts

In infected lungs the epithelium (wall of cells in the cavities of body) starts to peel and start to fill with foamy liquid.

Rapid unset; fever, cough, rapid breathing, and cyanosis (blue skin around the mouth/eyes

Death is caused by asphyxiation. If you don’t get treated the mortality rate is

100%. Lesions can also occur in lymph nodes,

spleen, liver, and bone marrow.

Pathogenesis and Clinical signs

Slide of Pneumocystis carinii from bronchi

Positive diagnosis is possible only with identification of parasite with staining.

To make a slide, a biopsy of lung tissue is needed.

These are the only tests used to accurately diagnose the parasite.

The parasite is extremely life threatening.

Diagnosis

X-ray ofPneumocystis carinii in the lungs

Pneumocystis carinii in lung tissue

Cysts are thick-walled, rounded and approximately 5-8 µm in size

Even with treatment, mortality is high in immunodeficient patients.

An antibacterial medicine is prescribed called trimethoprim- sulfamethoxazole (TMP SMX) or Bactrim.

Side effects of the drug may be: rash, sick feeling.

More medicine may need to be prescribed for the side effects.

Currently there is no vaccine for this fungus.

Treatment

If your immune system is weak or your CD4 cell count goes below 200, or if you display a temperature above 100 degrees for longer than two weeks.

Not contagious.

Control Measures

Any Questions?

Geographic Distribution ______ Mortality rate____% Life cycle with ____ and ____ Host ____

◦ Who is most susceptible_____ Clinical signs____ What is cyanosis_____ Size of cysts____ Method of Diagnosis ____ Treatment ____

Review – Candy!!

http://www.cdc.gov/hiv/resources/brochures/pcpb.htm

http://www.dpd.cdc.gov/dpdx/HTML/Pneumocystis.htm

http://course1.winona.edu/kbates/Parasitology/Images/pcarinii.jpg

http://www.lexic.us/definition-of/pneumocystis_carinii_pneumonia#2

Works cited