Fungi Flashcards
Fungi located in the Ohio-Mississippi river valley that produces calcifications and caseating granulomas, also causes pneumonia like symptoms; Dimorphic
Histoplasmosis
Fungi located in the central and southeastern United states that produces calcifications and suppurlative caseating granulomas; acquired by inhaling soil and rotten wood; broad based budding yeast; most commonly disseminates
Blastomycosis
Fungi located in the southwestern united states that produces calcifications and superlative caseating granulomas; Appears as spherules on microscopy; non-budding
Coccidioidomycosis
Most common fungi to affect the oral cavity
Candida albicans
Fungi-like bacteria
Actinomyces and Nocardia
What are the two growth forms fungi exist in?
1) Yeast
2) Mold (Hyphae septate or non-septate)
What molecule is important in the cell membranes of fungi?
1) Ergosterol
What is the target of drugs against fungi?
1) Ergosterol
Fungi that presents as subcutaneous nodules that occur due to trauma (rose thorn prick); secondary ndoules form along the lymphatic tract draining primary infection
Sporothrix schenckii
Subcutaneous nodule caused by a rose thorn prick
Sporothrix schenckii
Fungi that attack systemically; inhale spores from bird droppings; macrophates phagocytize spores and carry systemically; results in granulomas; common in Mississippi/Ohio river valley
Histoplasma capsulatum
What occurs when Histoplasma capsulatum are located within the macrophages?
1) They replicate as budding yeast
Chicken farmer presents from the Ohio River valley with pneumonia like symptoms, Granulomas appear with small calcium deposits on x-ray; after tissue biopsy yeast was found within macrophages
Histoplasma capsulatum
Fungi that resides in the soil as arthrospores, once inhaled become spherules and then infective endospores; may result in granulomas throughout the body
Coccidioides immitis
Spherules continaing endospores
Coccidioides
Old man visits Death valley. Upon returning from visit he has arthalgia, periarticular swellings, and erythema nodosum. Xray reveals granulomas in lungs
Coccidioides immitis
Fungi that when haled stimulates an IgE response? What is the name of this response?
1) Aspergillus fumigatus
2) Allergic bronchopulmonary aspergillosis
What is the result of an Aspergillus infection if there was previous history of TB
1) Aspergillus grow within the cavity
2) Formation of an aspergilloma
What occurs in an immunocompromised pt. who gets Aspergillus?
1) Aspergillus will enter the lung and invade the tissue
2) Occludes blood vessels and causes pulmonary infarction
What molecule is released by Aspergillus that is believed to be carcinogenic to the liver?
Alfatoxin
Tinea cruces
Jock itch
Yeast found in pigeon droppings that is inhaled and becomes pneumonia, may spread hematogenously causing meningitis; prevalent in immunosuppresed pt
Cryptococcus neoformans
What are the four opportunistic fungi?
1) pneumocystis jirovecii
2) Candida albicans
3) Cryptococcus neoformans
4) aspergillus fumigatus
Bird keeper presents with headache and stiff neck. Ct shows ring like lesions in brain and lumbar puncture reveals increased CSF pressure and encapsulated yeast
Cryptococcus neoformans
Systemic granulomas caused by inhaled fungal spore which become yeast; common In southeastern u.s.a
Blastomycesdermatitidis
Rarest yet most severe form of systemic fungal disease
Blastomyces dermatitidis
What fungi cause a systemic mycoses
1) blastomyces dermatitidis
2) coccidiosis
3) histoplasmosis
What does Candida albicans cause in a normal host? In an immunocompromised host?
1) oral thrush and vaginitis
2) esophagitis and systemic infection
How do amphotericin B and nystatin work? (Polyenes)
1) Work by binding to ergosterol and creating pores
How to the triazoles work to destroy fungi?
1) Work by inhibiting ergosterol synthesis
How do caspofungin and micafungin work?
1) Work by inhbiting glucan synthesis
Fungi that have cysts (containing dark oval bodies) inhaled in childhood, asymptomatic pneumonia; latent infection in lungs in immunocompromised; silver stain
Pneumocystis jirovecii
Treatment Pneumocystis jiroveciii
Trimethoprim-sulfamethoxazole
MOA of Caspofungin
1) Blocks glucan synthesis
2) Effective against Candida and Aspergillus
MOA of Amphotercin B
Binds to ergosterol and causes pore formation
MOA of azoles
Inhbition of ergosterol synthesis
Adverse effect of amphothercin B
Nephrotoxic
“Germ tubes” at 37 C; yeast at other temps
Candida albicans
When does Candida cause vaginitis occur most frequently?
1) When flora is decreased (decreased gram pos. bacteria)
2) Immunosuppresion
Treatment for Candida vaginitis
Fluconazole
Transparent capsules observed on india ink stain
Cryptococcus neoformans
Pt. with a history of immunocompromised state comes in complaining of headache, fever, lethargy; CSF has increased protein and decreased glucose; india ink stain shows transparent capsules
Cryptococcus neoformans
Budding yeast with thick capsule
Cryptococcus neoformans
Ovoid cells within macrophages
Histoplasmosis capsulatum
Mucicarmine
Cryptococcus neofromans
