Molecular diagnosis of candidemia by seminested PCR in critically ill patients

Abstract

Objectives: to standardize a molecular test based on semi-nested PCR for diagnosis of candidemia.

Methods: we developed a pilot study by means of optimizing the extraction protocol and use of ribosomal DNA, amplifying the complete ITS-2 region of Candida spp. and by semi-nested PCR reamplifying specific segments of nine clinically relevant Candida species. Clinical samples of plasma of critically ill patients with microbiologically proven candidemia from a third level hospital in Bogotá. Another sample of simulated candidemia was used with Candida strain form a urine sample.

Results: we were able to standardize this technique and achieved from clinical samples of plasma a likely sensitivity of 90% and a theoretical specificity of 100%. The detection capability of this test is up to 1 cell per 200 µl of plasma.

Conclusion: a molecular test for detection of candidemia among critically ill patients was standardized