Candidiasis
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:[1]
Candidiasis can be classified according to the site of infection into:
Localoized mucocutaneous candidiasis:
- 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
References
- ↑ "Candidiasis | Types of Diseses | Fungal Diseases | CDC".
- ↑ Mayer FL, Wilson D, Hube B (2013). "Candida albicans pathogenicity mechanisms". Virulence. 4 (2): 119–28. doi:10.4161/viru.22913. PMC 3654610. PMID 23302789.
- ↑ Donders GG, Babula O, Bellen G, Linhares IM, Witkin SS (2008). "Mannose-binding lectin gene polymorphism and resistance to therapy in women with recurrent vulvovaginal candidiasis". BJOG. 115 (10): 1225–31. doi:10.1111/j.1471-0528.2008.01830.x. PMID 18715406.
- ↑ Pappas PG (2006). "Invasive candidiasis". Infect. Dis. Clin. North Am. 20 (3): 485–506. doi:10.1016/j.idc.2006.07.004. PMID 16984866.