Chronic urinary tract infection due to Candida utilis

Area of Science:

• Medical Mycology
• Clinical Microbiology
• Urology

Background:

• Urinary tract infections (UTIs) are commonly caused by bacteria, with yeast infections being less frequent.
• Candida species are known causes of UTIs, but non-albicans Candida species are less common pathogens.
• Candida utilis, an industrially significant yeast, has not previously been reported as a cause of human urinary tract infections.

Observation:

• An elderly male patient presented with recurrent pyuria and yeast isolates over three years.
• Urine specimens consistently yielded "Candida species, not C. albicans" at significant concentrations.
• The yeast was identified as Candida utilis (anamorph) / Pichia jadinii (teleomorph) via conventional and molecular techniques.

Findings:

• The study confirms the isolation of Candida utilis from a patient's urine, marking the first documented instance of this yeast causing a UTI.
• Molecular methods, including karyotyping and restriction enzyme analysis, verified the identity and consistency of the isolates.
• The patient had co-existing conditions including benign prostatic hypertrophy and chronic obstructive pulmonary disease.

Implications:

• This case highlights the potential for unusual yeast species, like Candida utilis, to cause chronic and symptomatic urinary tract infections.
• The findings suggest that non-albicans Candida species, even those considered low-virulence or industrially significant, should be considered in the differential diagnosis of persistent UTIs.
• Further research is warranted to understand the clinical significance and pathogenic potential of Candida utilis in human infections.