STEP 1 Mycology 2 Flashcards
Mucor and Rhizopus spp. cause what disease?
Mucormycosis
In which patient population does mucormycosis occur? Why?
Disease occurs mostly in ketoacidotic diabetic and leukemic patients.
Fungi proliferate in blood vessel walls when there is excess ketones and glucose.
Pathogenesis of mucormycosis
Fungi proliferate in blood vessel walls when there is excess ketons and glucose. The fungi eventually penetrate the cribriform plate and then enter the brain
Signs and symptoms of mucormycosis:
- location of abscesses (2)
- Symptoms (3)
- Variable symptom
- Rhinocerebral and frontal lobe abscesses
- HA, facial pain, black necrotic eschar on face
- May have cranial nerve involvement depending on depth of penetration
Treatment for mucormycosis
Amphotericin B
Microscopy findings of mucor
“Irregular, broad, nonseptate hyphae branching at WIDE angles”
*Aspergillus is at 45 degrees…mucor is wide angles”
What does pneumocystis jirovecii cause?
I know you know it’s pneumonia…but what kind of pneumonia Alex? What kind?
Pneumocystis pneumonia…a diffuse, interstitial pneumonia
Transmission of pneumocystis?
Inhaled yeast
What does the Xray look like in pneumocystis?
How to diagnose?
Xray looks like hell. Well not really…its more diffuse and bilateral infiltrates.
Definitive diagnosis mad via lung biopsy or lavage
What does pneumocystis look like on microscopy? What is the best stain to use?
Disc-shaped yeasts.
Methenamine silver stain of lung tissue
Treatment for pneumocystis?
When to begin prophylaxis in HIV patients?
TMP-SMX. Treat prophylactically once CD4
Sporothrix schenckii causes what?
Sporotrichosis
What does Sporothrix look like on microscopy and where does it live?
Dimorphic, cigar-shaped budding yeast that lives on vegetation.
What is Sporothrix’s nickname?
Rose gardner’s disease. Usually introduced traumatically via thorn
What does Sporothrix look like clinically?
Local pustule or ulcer with nodules along **draining lymphatics.
“Ascending lymphangitis”
Little systemic illness
