Infections 6 Flashcards
Name the main anti-fungal drugs (6)
Polyenes Azoles Allylamines Echinocandins Flucytosine Griseofulrin
What is the mechanism of action of polyenes?
Polyenes bind to ergosterol forming pores in the cell membrane, leading to cell lysis
What is the mechanism of action of azoles?
Azoles inhibit lanosterol 14-alpha demethylase resulting in no ergosterol synthesis
What is the mechanism of action of allylamines?
Allylamines inhibit squalene epoxidase resulting in no lanosterol synthesis and ergosterol production
What is the mechanism of action of echinocandins?
Echinocandins inhibit the production of beta-1,3-glucan
What is the mechanism of action of flurocytosines?
Fluropyrimidine converts to 5-FU disrupting RNA/DNA synthesis
What is the mechanism of action of griseofulvins?
Griseofulvins bind to polymerised microtubules preventing the mitosis of fungal cells
How is candidiasis transmitted?
It is part of the commensal population of the skin
What are the symptoms of candidiasis?
Creamy curd like plaques on mucosal surface, pain and itching
What is the treatment for candidiasis?
Azoles e.g. Clotrimazole
How is aspergillosis transmitted?
By the inhalation of fungus
What are the symptoms of aspergillosis?
Wheezing, coughing, breathlessness
What is the treatment for aspergillosis?
Azoles e.g. Voriconazole
How is dermatophytosis transmitted?
Direct contact with the host organism
What are the symptoms of dermatophytosis?
Red scaly patches, itchy skin
What is the treatment for dematophytosis?
Head/scalp - Griseofulvin
Other (skin/nail) - Azoles e.g. clotrimazole, econazole
How is pityriasis versicolor transmitted?
Contact
What are the symptoms of pityriasis versicolor?
Brown, scaly patches on the skin
What is the treatment for pityriasis versicolor?
Topical azole e.g. Ketoconazole
How is histoplasmosis transmitted?
Inhalation of spores
What are the symptoms of histoplasmosis?
Cough or flu like symptoms
What is the treatment for histoplasmosis?
Oral azole e.g. Itraconazole
IV amphotericin B if severe
How is a cryptococcal infection transmitted?
Inhalation
What are the symptoms of a cryptococcal infection?
Fever Fatigue Dry Cough Headache Nausea
What is the treatment for a cryptococcal infection?
Amphotericin B
Name the FOUR mechanisms of anti-fungal resistance
Altered drug metabolism
Efflux pumps
Change in the protein target
Prevetnion of drug entry