Association Between Candiduria and Candidemia: A Clinical and Molecular Analysis of Cases

Best Practices in Treatment of Fungal Urinary Tract Infections

Fungal pathogens within the urine, specifically Candida species, are a common finding amongst hospitalized patients. Risk factors for the development of candiduria involve patients with indwelling urinary drainage devices, surgical patients, patients undergoing urologic instrumentation, and diabetic patients. Candiduria often presents with an asymptomatic course but can also be a severe life-threatening process. This article will review the epidemiology and risk factors associated with fungal urinary tract infections, and the diagnosis and categorization of these infections along with a review of current medical and surgical treatments for this condition.

Ascending renal infection following experimental candiduria by Candida tropicalis in immunocompromised mice

The present study evaluated renal infection resulting from the implantation of C. tropicalis in the bladder of immunosuppressed mice. Yeasts were implanted in two manners: planktonic and via preformed biofilm on a small catheter fragment (SCF). Renal histopathology and cultures was performed 72 and 144 h after cystotomy was carried out in mice from three groups: group I contained non-contaminated mice implanted with a sterile SCF; group II mice received a sterile SCF plus a yeast suspension containing 1 × 107 yeasts/mL in a planktonic form; group III mice were implanted with a SCF containing preformed C. tropicalis biofilm. Viable yeasts were found in the kidneys of mice from both groups II and III. However, after 72 h the planktonic cells (group II) invaded more quickly than the sessile cells (group III). Over a longer period (144 h), group III exhibited a more invasive infection (50% of the animals presented renal infection and the renal fungal load was 3.2 log10 CFU/g tissue) than in group II, where yeasts were not found. C. tropicalis introduced into the bladder in two ways (in planktonic or biofilm form) were able to reach the kidney and establish a renal fungal infection, causing interstitial disorders. The data of the present study therefore support the hypothesis of an ascending pathway for renal infections by C. tropicalis. Furthermore, the biofilm resulted in a greater and progressive risk of renal infection, attributed to the slow detachment of the yeasts.

Opportunistic Candida Infections in Critical COVID-19 Patients

The frequency of opportunistic fungal infections in critically ill patients whose intensive care unit stays are prolonged due to coronavirus disease 2019 (COVID-19) is higher than in the period before COVID-19. We planned this study to improve the management of Candida infections by defining the Candida species, the etiology of infections caused by Candida species, and the antifungal susceptibility of the species. This retrospective study included patients older than 18 hospitalized in the intensive care unit (ICU) with a definitive diagnosis of COVID-19 for seven months (from March 2021 to September 2021). All study data that we recorded in a standard study form were analyzed with TURCOSA (Turcosa Analytics Ltd. Co., Turkey, www.turcosa.com.tr) statistical software. The patients were evaluated in four groups as group 1 (candidemia patients, n = 78), group 2 (candiduria patients, n = 189), group 3 (control patients, n = 57), and group 4 (patients with candidemia in urine cultures taken before Candida was detected in blood culture, n = 42). Candida species were identified using both conventional and VITEK® 2 (BioMérieux, France) methods. The antifungal susceptibility of fungi was determined using the E test method. Of the 5,583 COVID-19 patients followed during the study period, 78 developed candidemia, and 189 developed candiduria. The incidence of candidemia (per 1,000 admissions) was determined to be 1.6. As a result of statistical analysis, we found that Candida albicans was the dominant strain in candidemia and candiduria, and there was no antifungal resistance except for naturally resistant strains. Candida strains grown in blood and urine were the same in 40 of 42 patients. Mortality was 69.2% for group 1, 60.4% for group 2, and 57.8% for group 3. Antifungals were used in 34 (43.5%) patients from group 1, and 95 (50.2%) from group 2. In the candidemia group without antifungal use, mortality was quite high (77.2%). Antifungal use reduced mortality in the group 2 (p < 0.05). Length of ICU stays, comorbidity, broad-spectrum antibiotics, and corticosteroids are independent risk factors for candidemia in critically ill COVID-19 patients. Our study contributes to the knowledge of risk factors for developing COVID-19-related candida infections. The effect of candiduria on the development of candidemia in critically ill COVID-19 patients should be supported by new studies.

Atypical Presentation of Bacteremic Urinary Tract Infection in Older Patients: Frequency and Prognostic Impact

In older patients, urinary tract infection (UTI) often has an atypical clinical presentation, making its diagnosis difficult. We aimed to describe the clinical presentation in older inpatients with UTI-related bacteremia and to determine the prognostic impact of atypical presentation. This cohort study included all consecutive patients older than 75 years hospitalized in a university hospital in 2019 with a UTI-related gram-negative bacillus (GNB) bacteremia, defined by blood and urine cultures positive for the same GNB, and followed up for 90 days. Patients with typical symptoms of UTI were compared to patients with atypical forms. Among 3865 inpatients over 75 with GNB-positive urine culture over the inclusion period, 105 patients (2.7%) with bacteremic UTI were included (mean age 85.3 ± 5.9, 61.9% female). Among them, UTI symptoms were reported in only 38 patients (36.2%) and 44 patients (41.9%) had no fever on initial management. Initial diagnosis of UTI was made in only 58% of patient. Mortality at 90 days was 23.6%. After adjustment for confounders, hyperthermia (HR = 0.37; IC95 (0.14–0.97)) and early UTI diagnosis (HR = 0.35; IC95 (0.13–0.94)) were associated with lower mortality, while UTI symptoms were not associated with prognosis. In conclusion, only one third of older patients with UTI developing bacteremia had UTI symptoms. However, early UTI diagnosis was associated with better survival.

Evaluation of a Novel Laboratory Candiduria Screening Protocol in the Intensive Care Unit

Background

Since urine cultures are only guaranteed for patients with obvious urinary symptoms in most cases, most of candiduria episodes are ignored in clinic.

Objective

This study aimed to design a screening protocol to improve diagnostic efficiency of candiduria, and provide information of Candida species and drug susceptibility.

Methods

All patients, who were admitted to the intensive care unit (ICU) of our hospital during December 1, 2018 and October 1, 2019, were enrolled in this study. Urinalysis was performed every three days for each subject from the first day of ICU admission. Urine specimens were sampled for fungal culture with either condition: (1) yeast-like cell counting (YLCC) ≥200; (2) positive YLCCs were observed in two consecutive tests, and at least one YLCC ≥100.

Results

The screening protocol dramatically improved the candiduria diagnostic rate of ICU patients from 2.28% to 17.27%. However, compared to the historical control, the screening protocol has no time-saving advantage in candiduria diagnosing. Higher percentage of C. albicans in screening protocol-identified candiduria patients was observed, although there was no statistical difference. Our results indicated that female gender, pneumonia, diabetes and infarction/hemorrhage patients were more prone to develop candiduria. Non-candiduria patients showed a better tendency for survival and shorter ICU stay length. Multisite colonization was common in the surveyed candiduria patients, who were up to 70.83% showed Candida positive cultures in sputum.

Conclusion

The screening protocol established in the study was a convenient and practical tool for early warning and feasible management of candiduria and IC.

Clinical and microbiological features of candiduria in critically ill adult patients in Shiraz, Iran (2016-2018): deviations from international guidelines and fluconazole therapeutic failure

Candiduria is common among patients admitted to intensive care units (ICUs); however, clinical and microbiological data are limited, which accounts for non-compliance with international guidelines, including over treatment of asymptomatic candiduria that promotes antifungal resistance. This prospective study included adult patients admitted to ICUs of five referral hospitals in Shiraz, Iran, during 2016-2018. Species were identified by MALDI-TOF MS, and antifungal susceptibility was assessed according to CLSI M27-A3/S4. Among 2086 patients, 162 and 293 developed candiduria and bacteriuria, respectively. In total, 174 yeast isolates were collected; 88.5% were Candida albicans (91/174; 52.2%), C. glabrata (38/174; 21.8%), and C. tropicalis (25/174; 14.3%). Antifungal resistance was rare; only two isolates (one C. tropicalis and one C. krusei) were fluconazole resistant. Symptomatic candiduria was noted in 31.4% of patients (51/162); only 37% (19/51) of them were treated and 36.82% (7/19) showed fluconazole therapeutic failure. Two symptomatic patients developed candidemia shortly after candiduria. Among asymptomatic patients, 31.5% (35/111) were overtreated with fluconazole. The mortality rate was 25.3% (41/162); it did not differ between symptomatic and asymptomatic patients. Our results indicate that deviation from standard-of-care treatment for candiduria is a matter of concern given the high rate of fluconazole therapeutic failure among patients with symptomatic candiduria.

LAY SUMMARY

Candiduria is an underestimated clinical presentation among critically ill patients and detailed data are scarce in this regard. Given the high rate of fluconazole therapeutic failure and development of candidemia in some cases, the mistreatment of candiduria should not be overlooked by clinicians.

Management of candiduria in hospitalized patients: a single-center study on the implementation of IDSA guidelines and factors affecting clinical decisions

Candiduria are common findings in clinic especially in hospitalized patients, while its significance remains undetermined. Since there are few criteria to follow, physicians tended to make decisions by personal experience in many cases in clinical practice. The present study was designed to unveil the present situation of candiduria management in hospitalized patients in clinical practice. A total of 251 hospitalized candiduria patients were retrospectively enrolled in the study. Clinical data on patient demographics, basic conditions, catheter using, urinary symptoms, laboratory data, and antifungal therapies were obtained from electronic medical records. The high rate of the candiduria cases were managed inappropriately after the introduction of the Infectious Diseases Association of America (IDSA) evidence-based recommendations, both in the management of urinary catheter and antifungal agents. Overtreatment was common in asymptomatic candiduria patients. For symptomatic patients, improper drug selections were not rare. In addition, a part of candiduria patients did not receive antifungal therapies although the IDSA recommends. A statistically significant difference was only found in hospital charges of symptomatic candiduria patients managed following IDSA or not. The recurrence rate, mortality, and hospital stay length were similar in candiduria patients regardless of the clinical management. Physicians tend to start empiric antifungal therapy for candiduria patients with pneumonia, multisite of Candida colonization, higher urine Candida CFUs, and long hospital stay. Candiduria has not received special attention today, and empirical antifungal treatment is common. IDSA guidelines are important to standardize the management of candiduria in clinic; however, the significance of the guidelines needs to be further clarified in future multicenter investigations.

Candida urinary tract infections in adults

Candiduria is commonly seen in hospitalized patients and most of the patients are asymptomatic, but it may be due to cystitis, pyelonephritis, prostatitis, epididymo-orchitis or disseminated candidiasis. Major risk factors are diabetes mellitus, indwelling urinary catheters, use of broad-spectrum antibiotics, urinary obstruction, and admission to intensive care units. Candida urinary tract infections can be caused by hematogenous spread following candidemia, or retrograde route via the urethra. The presence of Candida species in urine in asymptomatic patients does not warrant antifungal therapy except neutropenic patients, very low-birth-weight infants and patients undergoing urologic procedures. Fluconazole is the treatment of choice for symptomatic infections, it achieves high urinary levels. The other azole antifungals and echinocandins do not reach sufficient urine levels. Amphotericin B deoxycholate is the alternative antifungal agent if fluconazole can not be used because of resistance, allergy or failure.

Creation and assessment of a clinical predictive model for candidaemia in patients with candiduria

Candidaemia is the most common clinical presentation of invasive candidiasis and is a major cause of morbidity and mortality. Candiduria is a predictor for candidaemia; however, patient characteristics that are associated with concurrent candidaemia in the setting of candiduria are unclear. Identifying these characteristics could aid in the early detection of systemic disease. We performed a retrospective cohort analysis of hospitalised patients with candiduria at our institution over a 13-year period. Our evaluation of patient characteristics included demographics, comorbidities, medications, procedures, devices, vital signs and laboratory values. We developed a multivariable logistic model to identify factors associated with candidaemia in patients with candiduria. We identified 4240 patients with candiduria, 263 (6.2%) of whom had candidaemia. Predictors for increased risk of candidaemia with candiduria included hospitalisations > 12 days, central venous catheter, parenteral nutrition, haematological and gynaecological malignancy, and receipt of β-lactam/β-lactamase inhibitors. Vital signs and laboratory values associated with candidaemia included elevated heart rate, temperature and creatinine, along with neutropenia and neutrophilia. Factors that demonstrated a decreased risk of candidaemia included diabetes mellitus, gastrostomy and urinary catheter with antibiotic use. The c-statistic was 0.741 (95% CI, 0.710-0.772). We identified a set of clinical characteristics that can predict the presence of candidaemia with candiduria.

Candiduria in hospitalized patients: an investigation with the Sysmex UF-1000i urine analyzer

Background

Candiduria is common in hospitalized patients. Its management is limited because of inadequate understanding. Previous epidemiological studies based on culture assay have been limited to small study populations. Therefore, data collected by automated systems from a large target population are necessary for more comprehensive understanding of candiduria in hospitalized patients.

Methods

To determine the performance of the Sysmex UF-1000i in detecting candiduria, a cross-sectional study was designed and conducted. A total of 203 yeast-like cell (YLC)-positive and 127 negative samples were randomly chosen and subjected to microbiologic analysis. The receiver operating characteristic curve (ROC) was used to evaluate the ability of YLC counts as measured by the Sysmex UF1000i to predict candiduria. Urinalysis data from 31,648 hospitalized patients were retrospectively investigated, and statistical analysis was applied to the data collected.

Results

Using a cutoff value of 84.6 YLCs/µL, the sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of the yeast like cell (YLC) counts to predict candiduria were 61.7%, 84.1%, 88.6% and 66.3%, respectively. C. glabrata (33.6%) and C. tropicalis (31.4%) were more prevalent than C. albicans (24.3%) in the present study. Of the investigated hospitalized patients, 509 (1.61%) were considered candiduria-positive. Age, gender and basic condition were associated with candiduria in hospitalized patients. In the ICU setting, urinary catheterization appeared to be the only independent risk factor contributing to candiduria according to our investigation. Although antibiotic therapy has been reported to be a very important risk factor, we could not confirm its significance in ICU candiduria patients because of excessive antibiotic usage in our hospital.

Conclusions

The YLC measured by Sysmex UF-1000i is a practical and convenient tool for clinical candiduria screening prior to microbiologic culture. Candiduria is common in hospitalized patients, and its incidence varies according to age, gender and the wards where it is isolated. Candiduria had no direct connection with mortality but might be considered a marker of seriously ill patients who need particular attention in the clinic.

The Impact of 2015 NHSN Catheter-associated Urinary Tract Infection (CAUTI) Definition Change on Central Line-associated Bloodstream Infection (CLABSI) Rates and CLABSI Prevention Efforts at an Academic Medical Center

The 2015 changes in the catheter-associated urinary tract infection definition led to an increase in central line-associated bloodstream infections (CLABSIs) and catheter-related candidemia in some health systems due to the change in CLABSI attribution. However, our rates remained unchanged in 2015 and further declined in 2016 with the implementation of new vascular-access guidelines.Infect Control Hosp Epidemiol 2018;878-880.

Nosocomial Candiduria in the Elderly: Microbiological Diagnosis

Candiduria is associated with high morbidity, mortality, and long hospitalization, involving high costs for the healthcare system. The use of increasingly aggressive treatments has prolonged the lives of patients susceptible to candiduria, namely the immunosuppressed, the premature, and the elderly. Our objective was to evaluate the incidence of nosocomial candiduria and the implicated species in hospitalized patients aged over 80 years old from three Spanish centers during 2012 and 2013. Urine samples received from these patients were cultured and analyzed by flow cytometry in search of leukocyturia, hematuria, proteinuria, and microbial nitrate reductase activity. The isolated yeast species were identified microscopically, by germ tube formation in serum, colony morphology after subculture onto CHROMagar Candida (Becton-Dickinson, UK), assimilation of carbon compounds ID32C (bioMérieux, France), matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDITOF) (Bruker Daltonics, Germany) and, in case of inconsistency, by sequencing of the ITS regions of ribosomal DNA (ITS1-5, 8S-ITS2). Susceptibility tests were also performed. The incidence of candiduria in the elderly population was 10.3%. A total of 155 strains of yeasts were isolated. The predominant species was Candida albicans, followed by Candida glabrata and then Candida tropicalis. Several infrequent species were found; among them, the first isolate of candiduria-producing Candida pulcherrima described in the literature. Our finding should raise concerns about the elderly population, which is probably the most important risk group for candiduria in the present moment, and the emergence of unusual yeast species producing candiduria, which are resistant against the commonly used antifungal agents.