Candidiasis
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Candidiasis Main page |
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1];Associate Editor(s)-in-Chief: Ahmed Younes M.B.B.CH [2]
Overview
Causes
Classification
Classification:(1)
Candidiasis can be classified according to the site of infection into:
Localoized mucocutaneous:
- Oropharyngeal candidiasis
- Esophageal candidiasis
- Candida vulvovaginitis
- Chronic mucocutaneous candidiasis.
Invasive Candidiasis:
More serious and usually presenting in an immunocompromised host.
- Candidaemia
- Candida endophthalmitis
- Candida endocarditis
- Candida osteoarticular disease
Pathophysiology
Candida is a normal commensal of skin and mucous membranes. A competent immune system and an intact regenerating healthy skin prevent the virulence of Candida.
Candida Virulence factors
The main virulence factors that mediate the infection: (2)
- Secreting molecules that mediate adherence into host cells
- Production of hydrolases which has a lytic effect on tissues and facilitate the invasion by the bacteria.
- Polymorphism: Candida has the ability to grow either as pseudohyphae (elongated elipsoid form) or in a yeast form (rounded to oval budding form. While the role of #polymorphism is not clearly understood in the virulence of Candida, it’s noted that species capable of producing the most severe form of the disease has this ability.
- Biofilm production: which means the ability to form a thick layer of the organism on the mucosal surfaces or even on catheters and dentures.
Patients was candida vulvovaginitis were found to have decreased levels of mannose binding lectins (MBL) . Further investigations revealed that 2 genetic mutations in genes responsible for MBL and IL4 production increase the host susceotibility of getting recurrent candidal vulvovaginitis.(3)
Host immune defects
Any condition that compromises cell mediated immunity, worsens the general status of the patient or provide a favorable medium for candida to form biofilms put the patient at increased risk for having candidiasis.(4)
Conditions that compromises cell mediated immunity:
- T cell deficiencies as in DiGeorge syndrome, Wiscot-Aldrich syndrome and ataxia-telengictasia.
- Bone marrow transplant
- Leukaemias
- Corticosteroids use or immunosuppresive drugs.
Conditions that worsens the general condition:
- Malignancies
- Recent chemotherapy
- Trauma
- Recent surgery
- Prolonged hospitalization
- Broad spectrum antibiotics
- Renal failure
- Haemodialysis (especially if prolonged)
Dentures that provide a favorable media for forming biofilms:
- Prolonged central venous catheters insertion
- Prolonged foley’s catheter insertion
- Prolonged mechanical ventilation