Transcript C.Albicans

kingdom
Fungi Ascomycota
Saccharomycetes
Candida albicans (1)
phylum
class
genus
species
T. Walker, 10 Dec 03
Taxonomy, Ecology, Epidemiology
•
A common commensal, normally found in mouth, gastro-intestinal tract,
vagina (B, abstract)
– There is a bit of C. Albicans in the healthy intestine; bacteria that control
yeast growth may by killed through overuse of:
• antibiotics
• too much sugar consumption (feeding C. albicans,
which competes against the bacteria)
• altering pH to suit fungal growth through minimal
vegetable consumption (9).
•
Environmental presence due to human/animal contamination; b/c of this,
found in food, soil, and fomites.
– NOT normally found in environs, except when in mold form for transfer between
hosts.
– Infection by colonizing host’s organisms, e.g. the host’s hosts… (B)
•
Closely related to C.krusei, a cause of fungemia (derivative of sepsis) (3)
Yeast form of C.albicans (10,000x)
Note the reproduction by budding
Taxonomy, Ecology, Epid., c’ond; Prevention
• Medically-important fungi, dimorphic
[having two forms; here yeast when in
host, mold in environs – this is the YM
shift]
• As yeast, in skin/mucous membranes; is
type of opportunism (txt)
Infection symptoms;
• Include fatigue, sweat, pain, sore throat, fever,
numbness, asthma susceptibility, sinusitis,
allergies, irritabilty, abdomen pain, gas
• Notable are irregular menstrual cycles/pain, or
yeast rashes
– Possibly due to lack of estrogen or a menstrual cycle!
– If these symptoms untreated while young, may delay
menarche, and menopause may come earlier
(possibly early 20s).
Pathogenicity; Disease
• Medical abstract suggests “substantial differences in mortality,
organ colonization, and severity of tissue damage” after C.
albicans inoculation (A)
• If lacking a certain compliment in the brain, one is more susceptible
to disease caused by the fungus (A)
• Candida infections one-tenth of hospital bloodstream infections
• 80% AIDS patients have Candida
• Move from bloodstream to organs (4)
• Candidisis is a mycosis [a disease caused by fungi, here
C.albicans]; recognized since early 1800s under many names (txt)
Disease, con’d
• The fungi normally found in body, as mentioned;
growth usually limited by other organisms, but
causes candidisis when uncontrolled
Disease: Paronychia/onychomycosis
Disease: Candidisis
• Again, may be induced by overuse of
antibiotics (kills systemic bacteria that
control C.albicans growth); also
theraputic/surgical procedures (transplants
and prosthetics) that allow it to
contaminate body
• Also STD (txt)
Disease: Candidisis
• Symptoms include arthritis, various
inflammations (eye, heart, abdomen) (4, txt),
meningitis, myositis [muscular pain]
• Vaginal form: yeast infection
• Candidisis affects all organs and tissues!
• Other types are oral candidisis (thrush)
and diaper c’isis (when diapers moist and
erratically changed) (txt)
Oral candidisis: Thrush
Comprised of cellular debris, leukocytes, yeast cells (txt)
whassup!
Disease: Vulvovaginal C’isis (a
reiteration, of sorts); also Prevention
• +50% of women over 25yrs develop it
• Again, recurrance (in less than 5% of cases)
may b/c of:
–
–
–
–
–
Species similar to C. albicans acting “in place” of it)
Many antibiotics
Contraceptives (easier passage than dry skin)
Immunocompromization
Hyperglycemia (excess sugar) (9)
• One should avoid the above factors to repel c’isis, etc.
Treatment; Mortality
• In vitro techniques in conjunction w/
antifungal agents may counter Candida
• A suggested cure is limiting internal
adherance of the fungus; this concept is
not understood, however (6, abstract)
• Very high mortality: 46% mean mortality
from candidemia, with C.albicans involved
in 70% of those deaths (5)
Identification
• TefI gene from C. albicans and C.
dubliniensis amplified, compared to pure
fungal genome (7)
• Another confirmation method:
– After make inoculum, compare with
densitometer to known
– Incubate, then use system like FungiFast to
ID (similar to E-II, for those in 202)
– Based on colours produced by enzymes in
rxns… (8)
Identification: FungiFast table
Works Cited
• http://www.candidapage.com/cccomp.shtml (1)
• http://alces.med.umn.edu/candida/taxonomy.html (3)
• http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=Pu
bMed&list_uids=10999981&dopt=Abstract (11)
• http://pathology5.pathology.jhmi.edu/micro/v16n05.htm (5)
• http://www.unr.edu/mycology/ (6)
• http://www.int-microbio.com/Fungifast_ITwin.htm (8)
• http://www.excel.net/~jaguar/candida.html (9)
• http://www.pubmedcentral.nih.gov/articlerender.fcgi?rendertype=abs
tract&artid=174007 (A)
• http://www.smartcycler.com/pdfs/candidas_poster.pdf (7)
• http://www.intelihealth.com/IH/ihtIH/WSIHW000/9339/9935.html (E)
• http://www.aafp.org/afp/20000601/3306.html (9)
• Some definitions taken from www.m-w.com