candidiasis Flashcards
sx of candidiasis
mouth - white patches or erythema of buccal mucosa/ Patches may be hard to remove and bleed if scraped
pain in tongue
dysphagia
odynophagia
cracks, ulcers or crusted fissures radiating from angles of the mouth
oropharyngeal - white patches on erythematous background (plaque type), sore, inflammed areas (erythematous type)
GU - sore, white patches/discharge, itch, dyspareunia, burning
skin - in folds/interdigital
RF for candidiasis
extremes of age
DM, hypoPTH, hypoadrenalism
pregnancy
AB
immunosuppression - long term corticosteroids, including inhalers, cytotoxics, malignancy, HIV
hyposalvation/xerostomia
poor oral hygiene, especially among denture wearers
malabsorption and malnutrition - reduce effectivness of the immune response
Ix for candidiasis
endoscope
microscopy and culture - smear of lesion
definition of candidiasis
usually from candida albicans
commensal in mouth, vagina and GI tract
summarise invasive candidiasis
infection of the blood or normally sterile sites
in association with fever, hypotension and/or leukocytosis
in immunocompromised, comorbidity or ITU settomhs
genetic suseptibility
Estimated 250 000/yr with 50 000 deaths. Candidaemia in ~7/1000 ICU patients
organisms may be disseminated to multiple sites, notably retina, kidney, liver and spleen, bones, and the central nervous system.
Chronic disseminated candidiasis usually implies involvement of liver and/or spleen in association with recovery from chemotherapy-induced neutropenia.
sx of invasive candidiasis
RF for invasive fungal disease
febrile with no microbiological evidence for infection
new murmer
muscle tenderness
skin nodules
dx of invasive candidiasis
repeated blood/tissue culture
PCR
candida in resp secretions alone is insufficient
epidemiology for oral candidiasis
range from 40-70% of healthy children and adults - higher rates in children with carious teeth and older adults wearing dentures
carriage increase with cancer radiation, therapy, dm, HIV
colonisation may lead to opportunistic mucosal infection as well as disseminated and multi-system organ development in immunocompromised people
Antifungal agents are often used during radiation and chemotherapy to prevent opportunistic infection among patients under treatment for cancer
aetiology of oral candidiasis
candida albicans
dimorphic fungus - sperical or ovoid yeast cells or elongated hyphal forms, capable of penetrating epithelial tossies
A small subset of cases are due to one or more alternative species, such as C glabrata, C tropicalis, C parapsilosis, C guilliermondii, C krusei, or C dubliniesis, and most recently C auris
pathology of oral candidiasis
Establishment of infection requires a number of events,:
- including thigmotropism (contact sensing)
- attachment to epithelial cells
- intercellular penetration through secretion of secretory aspartyl proteinases and phospholipase B
ability to colonise and infect oral tissues requires specific local and systemic defects in host immune response
aetiology of systemic candidiasis
endogenous source of infection
generally unable to traverse intact epithelium
glabrata and C tropicalis are known to colonise the GI tract,
C parapsilosis tends to colonise skin and intravascular catheters, can be found on hands of healthcare workers.
pathology of systemic candidiasis
candida have specific receptors that assist in binding to mucosal surfaces
disruption of the epithelial barrier, usually through insertion of an IV catheter, gut mucosal ulceration due to chemi in pts with neutropenia, rarely from focal infections eg pyelonephritis secondary to an ascending UTI
The alteration of normal flora by giving broad-spectrum antibiotics allows the yeast to proliferate in high numbers during invasion
RF for invasive fungal disease
use fo central venous catheter
exposure to broad spectrum AB
haemodialysis
surgery
parenteral nutrition
innunosuppressants eg chemo, systemic, corticosteroids
Ix for systemic candidiasis
blood culture
FBC - WCC and thrombocytopenia
ABG - hypoxia, hypercapnia
lactate levels - hyperlactataemia
coagulation studies - prolongued
renal func tests - creatinine twice normal, sign of sepsis
liver func tests - sepsis - high alanine amminotransferase, aspartate aminotransferase, alkphos, GGT, BR
serum glucose
