Relationship between Sap prevalence and biofilm formation among resistant clinical isolates of Candida albicans

Afr Health Sci. 2018 Dec;18(4):1166-1174. doi: 10.4314/ahs.v18i4.37.

Abstract

Background: Fungal infections represent a serious health problem especially in immunocompromised individuals. Candida albicans is the most common fungi that cause superficial and systemic infections with high mortality rates. Anti-fungal resistance of C. albicans may be attributed to its virulence. Biofilm formation and proteolytic activity are major virulence determents that may influence both pathogenicity and anti-fungal resistance of Candida albicans.

Objective: This work studied the relation between biofilm formation, proteolytic activity and prevalence of some Sap genes with reduced susceptibility of C. albicans to different anti-fungal agents.

Methods: Fifty three C. albicans strains isolated from patients with systemic infections, identified by germ tube, chromogenic agar and confirmed by PCR, were subjected to evaluate their proteolytic activity, the degree of biofilm production and the prevalence of Sap9 and Sap10 genes. The susceptibility of the isolates was determined by disk diffusion method against five antifungal drugs.

Results and conclusion: Four of the C. albicans isolates were resistant to 3 anti-fungal drugs, strong biofilm producer, have proteolytic activity and contain either Sap9 or Sap10 or both. Conclusively, although anti-fungal resistance among the isolates was rare, a relation between the anti-fungal resistance and some major virulence factors was evidently proved in this study.

Keywords: Candida albicans; Sap; biofilm; proteolytic; resistance.

MeSH terms

  • Antifungal Agents / pharmacology
  • Aspartic Acid Endopeptidases / genetics*
  • Biofilms
  • Candida albicans / classification
  • Candida albicans / genetics*
  • Candida albicans / isolation & purification*
  • Candida albicans / physiology
  • Drug Resistance, Fungal / genetics*
  • Fungal Proteins / genetics*
  • Genotype
  • Humans
  • Microbial Sensitivity Tests
  • Peptide Hydrolases / metabolism
  • Phenotype
  • Prevalence
  • Virulence
  • Virulence Factors

Substances

  • Antifungal Agents
  • Fungal Proteins
  • Virulence Factors
  • Peptide Hydrolases
  • Aspartic Acid Endopeptidases
  • Sap10 protein, Candida albicans
  • Sap9 protein, Candida albicans