Pneumocystis carinii

Pneumocystis cariniiPresented by: Samantha Todd & Sandra Thorbus

Pneumocystis carinii vs. jirovecii

Both Pneumocystis carinii and Pneumocystis jirovecii (yee row vet zee) currently refer to the same organism. P. jirovecii is the organism isolated from humans, while P. carinii is found in rats.Not a protozoan, but a fungus.

HostsDefinitive Host: Humans, other mammals. Intermediate Host: None

PrevalenceAIDS/HIV patientsImmunosuppressed individualsOrgan transplant recipientsChemotherapy patientsPremature, malnourished infants

Most healthy children have been exposed by age 5

GeographyWorldwide

Three Morphological Forms

All three forms are found in the lungs1. Precyst

Oval shapedFew filopodiaCell wall thickeningIncrease in number of nuclei from one to four

Three Morphological Forms1. Cyst

-Mature cysts are spherical, have a thick chitinous membrane and eight intracystic bodies (young trophozoites)

Three Morphological Forms3. Trophozoite

Filopodia form pockets in interstitial cellsMost abundant during infection (9:1)

Life Cycle

Life CycleInhalation of infective respiratory dropletsMakes its way inside the respiratory tract, settles into alveolar spaces and replicates:

Asexual Reproduction1. Trophozoite reproduction

Sexual Reproduction1. Conjugation2. Formation of Precyst3. Formation of early cyst4. Maturation and ExcystmentLife cycle repeats

TransmissionFound in environment, lungs & upper respiratory tract of humans and animalsSpread by inhalation of infected respiratory droplets

Symptoms Causes Pneumocystis Pneumonia (PCP)FeverCoughShortness of breathCyanosisNon-productive coughChest painMalaise

Symptoms develop more slowly in those with AIDS and tend to be less severe

DiagnosisSputum examinationLung biopsyBronchial lavageBlood gas testChest X-rayMortality rate is 100% in untreated patients.

Cysts of Pneumocystis carinii in smear from bronchoalveolar lavage.

TreatmentTrimethoprin-sulfamethoxazole (TMP/SMX, Bactrim)Intravenous or oral administrationAlternative Treatments include:

PentamidineAtovaquoneCombination of Trimethoprin and Dapsone

PreventionPrimary PCP prophylaxis (preventative antibiotic treatment before the onset of disease)Reduces occurrence of PCP by 90%

Reviewhttp://www.youtube.com/watch?v=cuZb539SaaY

Bibliographyhttp://www.pathologyimagesinc.com/emhandbook/opport-infections-section/inf-agents-pages/pneumocystis-carnii.htmlhttp://microbewiki.kenyon.edu/index.php/Pneumocystis_cariniihttp://www.nlm.nih.gov/medlineplus/ency/images/ency/fullsize/17278.jpghttp://health.nytimes.com/health/guides/disease/pneumocystis-carinii-pneumonia/overview.htmlhttp://pathmicro.med.sc.edu/mycology/opportunistic.htmhttp://www.healthscout.com/ency/68/558/main.html#PreventionofPneumocystisCariniiPneumonia(PCP)http://dpd.cdc.gov/dpdx/html/Pneumocystis.htmhttp://summaries.cochrane.org/CD005590/antibiotic-treatment-for-the-prevention-of-pneumocystis-pneumonia-pcp-in-non-hiv-immunocompromised-patients