Micro- Mycology and parasitology Flashcards
How are local vs systemic mycoses treated?
local: fluconazole, itraconazole
systemic: amphotericine B
Common in Missippi and Ohio River Valley
Causes pneumonia
Histoplasmosis
Histo shows macrophage filled with small spherules (smaller than RBC)
Histoplasmosis
Common in states east of Mississippi river, central america
Causes pneumonia that can disseminate to bone and skin
Blastomycosis
Pneumonia with broad-base budding yeast
Blastomycosis
Southwestern US, California
causes pneumonia and meningitis
can also have erhythema nodosum, arthralgias
Coccidiodomycosis
Spherules (much larger than RBCs) filled with endospores
Coccidiodomycosis
Common in Latin America
“captain’s wheel” formation budding yeast
Paracoccidiomycosis
What systemic mycosis is a spherule in tissue
Coccidiomycosis
Causes hyper or hypopigmented skin patches
spaghetti and meatball appearance
Malassezia furfur
What do the dermatophytes infect:
Microsporum
Trichophyton
Epidermophyton
Microsporum- hair, skin
Trichophyton- skin, hair, nails
Epidermophyton- nail, skin
What type of infection is common following Tb?
aspergilloma
What type fungus has septate hyphae branching at 45deg?
aspergillus
What forms a condiophore with radiating chains of spores?
aspergillus
What can cause bronchiectasis and eosinophilia and is associated with asthma and CF
Allergic bronchopulmonary aspergillosis
What fungal infection is associated with Hepatocellular carcinoma?
aspergillus aflatoxins
5-10um yeasts with wide capsular halos and unequal budding
Cryptococcus neoformans
What is cultured on Sabouraud agar?
Cryptococcus neoformans
Describe how Cryptococcus neoformans causes meningitis?
acquired via inhalation, spreads hematogenously to lungs
What is a common cause of meningitis in AIDS patients?
Cryptococcus neoformans
Shows “soap bubble” lesions in brain
Cryptococcus neoformans
How does one test for Cryptococcus neoformans?
positive latex agglutination test
What type of patients are susceptible to mucormycosis?
ketoacidic diabetic and leukemic patients
Causes rhinocerebral frontal lobe abscesses
Mucor/rhizopus
Describe how mucor infects?
proliferates in blood vessels, penetrates cribiform plate and enters brain
How is PCP diagnosed?
lung biopsy or lavage
Shows diffuse, bilateral CXR; disk shaped yeast on methenamine silver stain
PCP
When should prophylaxis for PCP be started?
CD4 <200
Dimorphic, cigar-shaped yeast that lives on vegetation
Sporothrix schenkii
Causes bloating, flatulence, foul smelling fatty diarrhea
Giardia lamblia
What is the treatment for Giardia?
Metronidazole
Cysts with up to 4 nuclei in the stool
Entamoeba histolytica
Diagnosed by oocysts in acid-fast stain
Cryptosporidium
Causes severe diarrhea in AIDS patients
Cryptosporidium
What is the treatment for Cryptosporidium?
Nitazoxanide
Causes bloody diarrhea and liver abscess
Entamoeba histolytica