Antifungals and Foundations Immunology Flashcards
What is the structure of a fungus ?
They are multicellular Eukaryotic organisms with well defined nucleus, and organelles. However, their cell walls have no peptidoglycan, but sterois. They undergo mitotic division and have DNA with histone. They have more than one chromosome and has a size range of 10-100 micrometeres.
What are the two different types of micotic infections ?
Superficial and systemic infections.
What are the two types of superficial infections ?
(1)dermatomycoses
(2)candidiasis
What is dermatomycoses?
These are infections of the skin,
hair and nails commonly due to Tinea organisms.
What is superficial candidiasis ?
It is infection
of yeast-like organism
within the mucous membranes of
the mouth, vagina or skin.
What is an example of systemic micotic infection ?
Cryptococcal meningitis: Caused by the
fungus Cryptococcus. Mainly infects
immunocompromised patients.
What are the causes of fungal endocarditis?
Candida and
Aspergillus species most common.
What is Pulmonary aspergillosis?
Aspergilloma is a growth (fungus ball) that
develops in an area of past lung disease
or lung scarring such as tuberculosis
or lung abscess. Invasive pulmonary
aspergillosis is a serious infection with
pneumonia. It can spread to other parts of
the body
What is the general classification of anti-fungal drugs ?
1.) Drugs that disrupt the fungal cell membrane/wall
2.) Drugs that inhibit processes within the fungal cell
What is the action of Amphotericin B?
It is a polyene with fungicidal and fungistatic MOA and is used to treat systemic mycoces. The drug binds to ergosterol and forms large pores in the membrane through which intracellular ions leak out – this causes fungal cell death.
What are the modes of administration of Amphotericin B?
The drugs can be given topically ,iv admin, liposomes, losenges and has wide distribution.
What are the side effects of Amphotericin B?
fever, renal impairment, hypotension, anaemia
What is the action of Echinocandins?
They inhibit a key enzyme beta (1,3)-D–Glucan synthase necessary for integrity of the fungal cell wall which makes the fungi susceptible to
osmotic instability and cell death.
What are the two types of Echinocandins?
Caspofungin
Micafungin
What is the action and indication of Flucytosine (5-fluorocytosine)?
They are indicated for the treatment of subcutaneous and systemic fungal infections. It is generally used only in combination with amphotericin B for systemic mycoses and meningitis. It acts by inhibiting nucleic acid
synthesis.
