Pneumocystis jiroveci, Microsporidia, etc

Question 1

Pneumocystis (carinii) jiroveci General Biology

Answer 1

Classified as a Fungus but missing fungal components in PM. Two stages: trophozoites and cysts in lungs. transmitted in air.

Question 2

Active infection of Pneumocystis (carinii) jiroveci

Answer 2

degenerates alveolar epithelium and fills spaces with cysts, debris, plasma cells. Causes foamy apperance in lungs, thickening of septa. eventually causes tachypnea and dyspnea and non-productive cough, fever, rales

Question 3

Diagnosis of Pneumocystis (carinii) jiroveci

Answer 3

bilateral diffuse interstitial and alveolar infiltrate evenly invading ALL portions of the lung X-ray. Bronchoalveloar lavage via methenamine silver.

Question 4

Pneumocystis (carinii) jiroveci Epidemiology

Answer 4

occurs in immunocompromised patients, including those with AIDS, malnourished or premature babies. AIDS patients given prophylactic treatment reduces number of cases

Question 5

Microsporidia general characteristics

Answer 5

7 genera and 13 species have been found in humans
Spore has an extrusion apparatus consisting of polar tubule coils that dominates the spore contents. After the spore is ingested, the everted coiled tube penetrates host cells and injects sport contents into the cell cytoplasm. The parasite then divides and spread to other tissues or to the environment

Question 6

Clincal Presentation in AIDS patients

Answer 6

GI infections causes chronic diarrhea wasting, malabsorption. corneal infections lead to conjunctival irritation, photophobia, foreign body sensation. Modes of transmission not known

Question 7

Epi and Diagnosis of Microsporidia

Answer 7

electron/light level microscopy with special stains. found in Aids patients

Question 8

Toxoplasma gondii General Characteristics

Answer 8

Obligate intracellular parasite that infects all mammals and birds
Infects all cells EXCEPT erythrocytes

Question 9

Life Cycle of Toxoplasma gondii

Answer 9

sexual reproduction in intestine of cats ooyctes released in feces. Parasites invaded macrophages and replicated there

Question 10

Chronic Infections of Toxoplasma gondii

Answer 10

Develop in the brain and muscle. viable for life of the host where they can rupture or infected other hosts if eaten.

Question 11

Congenital transmission of Toxoplasma gondii

Answer 11

most infections during pregnancy particuarly in the third trimester. Most disease occurs in the first trimester. Can transfer to the fetus.

Question 12

Heart transplant recipients Transmission of Toxoplasma gondii

Answer 12

Serelogical negative patient receives a heart from seropositive donor. serious disease can occur and prophylactic treatment.

Question 13

Congenital Infection of Toxoplasma gondii

Answer 13

May be abortion or stillbirth. If fetus survives, may be cerebral calcification, hydrocephalus or microcephaly . Retinochoroiditis can occur later in life.

Question 14

AIDS Patient P Infection of Toxoplasma gondii

Answer 14

Half develop cerebral toxoplasmosis. Most commonly due to recrudescence of a latent infection. Can led to brain necrosis and death. Chorioretinitis Is not Common

Question 15

Diagnosis of Toxoplasma gondii

Answer 15

Serology, CT and MRI for AIDS patient

Question 16

Prognosis of Toxoplasma gondii

Answer 16

Treatment usually not needed unless it severe symptoms or active retinochoriditis. life long therapy for immunocompromised patients.

Question 17

Cryptosporidium parvum General Biology

Answer 17

Sexual and asexual reproduction occurs in the intestinal tract of a single host: Oocysts released in the stool are ingested and then sporozoites exit and attach to microvilli of small intestine epithelial cells. After a few cycles of asexual reproduction, gametes form which fuse to yield an oocyst. Oocysts are immediately infective

Question 18

Normal Patients Infection of Cryptosporidium parvum

Answer 18

Watery, explosive and perfuse diarrhea with abdominal pain, anorexia, malaise, myalgia and weight loss. NO reinfection

Question 19

Immunocompromised Patients Cryptosporidium parvum

Answer 19

Parasites are found throughout the GI tract and may be found in the lungs, liver and elsewhere
Severe diarrheal illness characterized by frequent, voluminous watery bowel movements persistent for months

Question 20

Cryptosporidium parvum location

Answer 20

resides under the cell membrane of the microvilli

Question 21

Transmission of Cryptosporidium parvum

Answer 21

Worldwide, Person-to-person transmission is the primary method of transmission, food or water contamination by human or animal feces is secondary

Question 22

Cryptosporidium parvum Epidemiology

Answer 22

Found worldwide, but more commonly in the tropics. Seroprevalence US: 25% and Tropical regions (e.g. Venezuela): 65%

Question 23

Diagnosis of Cryptosporidium parvum

Answer 23

Acid-fast or fluorescent staining for oocysts in feces

Question 24

Cyclospora cayetanensis

Answer 24

very similar to Cryptosporidium. Infection associated with fever, ab pain, and diarrhea. Water and some fruits (raspberries).