From the Guidelines
The diagnosis of yeast UTI should be based on a combination of clinical presentation, laboratory findings, and imaging studies, rather than relying solely on urine culture results, as colonization and infection can be difficult to differentiate 487, 1. When evaluating a patient for a yeast UTI, it is essential to consider the clinical context, including symptoms such as dysuria, frequency, urgency, or suprapubic pain, as well as risk factors like diabetes, immunosuppression, recent antibiotic use, indwelling urinary catheters, and pregnancy.
- Key diagnostic findings include:
- Pyuria (white blood cells in urine)
- Hematuria
- Visualization of yeast cells on microscopy
- Imaging studies, such as ultrasound or CT scanning, to define structural abnormalities, hydronephrosis, abscesses, emphysematous pyelonephritis, and fungus ball formation [490–492,1]
- The presence of yeast in urine culture with a colony count of >10^3-10^4 CFU/mL can support the diagnosis, but it is crucial to differentiate between colonization and infection 488, 489, 1.
- Fluconazole is the drug of choice for treating Candida UTI, with a recommended dose of 200mg on day 1 followed by 100mg daily for 7-14 days for uncomplicated cases 496, 1.
- For catheterized patients, catheter removal or replacement is essential when possible, and irrigation of the bladder with AmB deoxycholate may be considered in some cases, although it is generally discouraged due to the risk of recurrent candiduria [503–505,1].
- It is also important to address underlying risk factors to prevent recurrent infections, such as managing diabetes, avoiding unnecessary antibiotic use, and removing indwelling urinary catheters when possible 94, 1.
From the Research
Criteria for Yeast UTI
The following criteria can be used to diagnose and treat yeast UTI:
- Candiduria is a nonspecific finding that can occur due to contamination of a urine sample, colonization of an indwelling catheter and/or the bladder, symptomatic cystitis, and invasive upper tract infection 2
- Most patients with candiduria are colonized and do not require antifungal therapy, and removing predisposing factors such as indwelling catheters and antibiotics can clear candiduria in almost 50% of asymptomatic patients 2
- For patients with symptomatic Candida urinary tract infections, treatment options include fluconazole, amphotericin B, and flucytosine, with fluconazole being the antifungal agent of choice 2, 3
Treatment Options
- Fluconazole is the recommended treatment for symptomatic Candida urinary tract infections, with a dose of 200-mg loading dose followed by 100 mg/d for at least four days 3
- Amphotericin B and flucytosine can be used in rare cases, but newer azole agents and echinocandins are not recommended due to inadequate urine concentrations 2
- Posaconazole has been shown to be effective against yeasts, including fluconazole-resistant Candida albicans, but its use in treating yeast UTI is not well established 4, 5
Antifungal Resistance
- Some yeast species, such as Candida dubliniensis, can develop resistance to fluconazole more rapidly than other species 5
- Antifungal resistance can be a concern in treating yeast UTI, and susceptibility testing may be necessary to guide treatment decisions 6
- Certain yeast species may exhibit unusual MIC distributions, indicating potential resistance to one or more antifungal agents 6