Urinary tract candidiasis: report of a case with bilateral ureteral obstruction

A brief review of the literature on urinary tract candidiasis is presented. The presence of Candida albicans in the urine is rather uncommon and most patients have candiduria without any apparent disease. Among the others, three different clinical types of infection are recognized: (1) pyelonephritis, (2) lower urinary tract infection and (3) ureteral obstruction. Of this last type only seven cases were found in the literature; four of the patients died. We add one case in which the patient did very well after the obstruction of the ureters was relieved by means of ureteral catheters and a large urinary output was maintained for several days.     

An in vitro urinary tract catheter system to investigate biofilm development in catheter-associated urinary tract infections

Biofilm development in urinary tract catheters is an often underestimated problem. However, this form of infection leads to high mortality rates and causes significant costs in health care. Therefore, it is important to analyze these biofilms and establish avoiding strategies. In this study a continuous flow-through system for the cultivation of biofilms under catheter-associated urinary tract infection conditions was established and validated. The in vitro urinary tract catheter system implies the composition of urine (artificial urine medium), the mean volume of urine of adults (1 mL min^-1), the frequently used silicone catheter (foley silicon catheter) as well as the infection with uropathogenic microorganisms like Pseudomonas aeruginosa. Three clinical isolates from urine of catheterized patients were chosen due to their ability to form biofilms, their mobility and their cell surface hydrophobicity. As reference strain P. aeruginosa PA14 has been used. Characteristic parameters as biofilm thickness, specific biofilm growth rate and substrate consumption were observed. Biofilm thicknesses varied from 105 ± 16 μm up to 246 ± 67 μm for the different isolates. The specific biofilm growth rate could be determined with a non invasive optical biomass sensor. This sensor allows online monitoring of the biofilm growth in the progress of the cultivation.     

An in vitro urinary tract catheter system to investigate biofilm development in catheter-associated urinary tract infections

Biofilm development in urinary tract catheters is an often underestimated problem. However, this form of infection leads to high mortality rates and causes significant costs in health care. Therefore, it is important to analyze these biofilms and establish avoiding strategies. In this study a continuous flow-through system for the cultivation of biofilms under catheter-associated urinary tract infection conditions was established and validated. The in vitro urinary tract catheter system implies the composition of urine (artificial urine medium), the mean volume of urine of adults (1 mL min^–1), the frequently used silicone catheter (foley silicon catheter) as well as the infection with uropathogenic microorganisms like Pseudomonas aeruginosa. Three clinical isolates from urine of catheterized patients were chosen due to their ability to form biofilms, their mobility and their cell surface hydrophobicity. As reference strain P. aeruginosa PA14 has been used. Characteristic parameters as biofilm thickness, specific biofilm growth rate and substrate consumption were observed. Biofilm thicknesses varied from 105 ± 16 μm up to 246 ± 67 μm for the different isolates. The specific biofilm growth rate could be determined with a non invasive optical biomass sensor. This sensor allows online monitoring of the biofilm growth in the progress of the cultivation.     

Characteristics of Biofilms from Urinary Tract Catheters and Presence of Biofilm-Related Components in Escherichia coli

Long term catheterization of the urinary tract leads to bacterial colonization of the urine, whereby adherence to the catheter surface is a major determinative factor for colonization. Collection of bacterial isolates from urine and urinary catheters of 45 patients showed multi-species catheter-colonization, while Escherichia coli isolates were frequently found in the urine in high numbers. Biofilm formation of catheter and urine-derived E. coli isolates was associated with the presence of the fluA gene, loss of O-antigen, and expression of type 1 fimbriae. The second messenger cyclic di-GMP (cdiGMP), a major regulator of biofilm formation, regulated adherence to the catheter surface in a selected clinical isolate suggesting that the cdiGMP second messenger pathway may be a target for anti-biofilm therapeutic approaches.     

Diurnal fluctuations of protein contents and the pH dependence of β<Subscript>2</Subscript>-microglobulin stability in urine

Diurnal fluctuations of protein excretion into urine and the effect of urinary pH on the urinary protein concentrations were studied in patients with various kidney diseases. The diurnal kinetics of γ-immunoglobulin, transferrin, albumin, α₁-microglobulin, γ-immunoglobulin light chains, and the retinol-binding protein proved to positively correlate with the diurnal fluctuations of proteinuria and to negatively correlate with urinary pH. Diurnal changes in urinary β₂-microglobulin content did not correlate with those of any other protein. Oral bicarbonate intake alkalinized the urine, increased the urinary β₂-microglobulin content, and led to a direct correlation between β₂-microglobulin excretion and excretion of other low-molecular proteins. Thus, proteinuria, single protein excretion, and urinary pH displayed diurnal rhythmicity in the patients; β₂-microglobulin was unstable in acid urine and its urinary level depended on the urinary pH.     

Infecciones urinarias nosocomiales por levaduras. Estudio multicéntrico de 14 hospitales de la red de micología de la Ciudad Autónoma de Buenos Aires

BackgroundUrinary tract infections are a frequent ailment in patients in intensive care units. Candida and other yeasts cause 5-12% of these infections. The value of the finding of any yeast is controversial, and there is no consensus about which parameters are adequate for differentiating urinary infections from colonization or contamination.AimsTo analyse the epidemiological characteristics of patients with funguria, to determine potential cut-off points in cultures (to distinguish an infection from other conditions), to identify the prevalent yeast species, and to determine the value of a second urine sample.MethodsA multicentre study was conducted in intensive care units of 14 hospitals in the Buenos Aires City Mycology Network. The first and second samples of urine from every patient were cultured. The presence of white cells and yeasts in direct examination, colony counts, and the identification of the isolated species, were evaluated.ResultsYeasts grew in 12.2% of the samples. There was no statistical correlation between the number of white cells and the fungal colony-forming units. Eighty five percent of the patients had indwelling catheters. Funguria was not prevalent in women or in patients over the age of 65. Candida albicans, followed by Candida tropicalis, were the most frequently isolated yeasts. Candida parapsilosis and Candida glabrata appeared less frequently. The same species were isolated in 70% of second samples, and in 23% of the cases the second culture was negative.ConclusionsIt was not possible to determine a useful cut-off point for colony counts to help in the diagnosis of urinary infections. As in other publications, C. albicans, followed by C. tropicalis, were the most prevalent species.     

In Vitro Evaluation of the Efficacy of a Silver-Coated Catheter

Bacteria commonly associated with nosocomial urinary tract infections were examined in vitro for their relative adherence to latex, 100% silicone-, hydrogel-coated latex-, and hydrogel/silver-coated latex urinary catheters. Degrees of adherence within 2 h were determined with cells radiolabeled with leucine. Adherence was greatest and equivalent on silicone and latex catheters. Adherence of four strains of Escherichia coli to the hydrogel/silver-coated catheter was decreased by 50% to 99% in comparison with the other catheters. Repeat testing with strains of E. coli and Pseudomonas aeruginosa with over 50 catheters demonstrated a consistency in the inhibition. The hydrophilic coating of the catheter appeared to be primary in the decreased adherence phenomenon followed by a secondary biocidal effect of the silver ion. Received: 2 December 1995 / Accepted: 3 January 1996     

High urinary excretion of lipid peroxidation-derived DNA damage in patients with cancer-prone liver diseases

Chronic inflammatory processes induce oxidative and nitrative stress that trigger lipid peroxidation (LPO), whereby DNA-reactive aldehydes such as trans-4-hydroxy-2-nonenal (HNE) are generated. Miscoding etheno-modified DNA adducts including 1,N⁶-etheno-2′-deoxyadenosine (?dA) are formed by reaction of HNE with DNA-bases which are excreted in urine, following elimination from tissue DNA. An ultrasensitive and specific immunoprecipitation/HPLC-fluorescence detection method was developed for quantifying ?dA excreted in urine. Levels in urine of Thai and European liver disease-free subjects were in the range of 3–6 fmol ?dA/μmol creatinine. Subjects with inflammatory cancer-prone liver diseases caused by viral infection or alcohol abuse excreted massively increased and highly variable ?dA-levels. Groups of Thai subjects (N = 21) with chronic hepatitis, liver cirrhosis, or hepatocellular carcinoma (HCC) due to HBV infection had 20, 73 and 39 times higher urinary ?dA levels, respectively when compared to asymptomatic HBsAg carriers. In over two thirds of European patients (N = 38) with HBV-, HCV- and alcohol-related liver disease, urinary ?dA levels were increased 7–10-fold compared to healthy controls. Based on this pilot study we conclude: (i) high urinary ?dA-levels, reflecting massive LPO-derived DNA damage in vivo may contribute to the development of HCC; (ii) ?dA-measurements in urine and target tissues should thus be further explored as a putative risk marker to follow malignant progression of inflammatory liver diseases in affected patients; (iii) etheno adducts may serve as biomarkers to assess the efficacy of (chemo-)preventive and therapeutic interventions.     

内毒素和降钙素原在妇科术后尿路感染中的鉴别诊断价值

目的评价中段尿内毒素和血清降钙素原在妇科术后不同种类细菌尿路感染中的鉴别诊断价值。方法收集临床1205例妇科术后患者中段尿进行细菌培养及内毒素检测,同时对患者进行血清降钙素原检测,比较结果对尿路感染的鉴别诊断价值。结果1205份标本中尿培养出阳性350例,感染率为29．04％,其中298例为均存在留置导尿管,而在剩余400例尿培养阴性的患者中仅仅120例留置导尿管。两组之间差异有统计学意义（χ2=26．78,P〈0．05）。其中革兰阴性杆菌189例（54％）,革兰阳性菌112例（32％）,真菌49例（14％）。在三组患者中,中段尿内毒素在革兰阴性菌引起的术后尿路感染较革兰阳性菌和真菌的患者中明显升高,差异均有统计学意义（P〈0．05）。而对于血清降钙素原在革兰阴性菌和革兰阳性菌感染的患者明显高于真菌尿路感染的患者,差异均有统计学意义（P〈0．05）。而在革兰阴性菌和革兰阳性菌感染的患者中差异无统计学意义（P〉0．05）。结论妇科术后尿路感染与留置导尿管密切相关,革兰阴性菌是引起妇科术后尿路感染的主要致病菌,中段尿内毒素有助于鉴别诊断出革兰阴性菌引起尿路感染,而血清PCT升高时则有助于排除真菌尿路感染。     

dsdA Does Not Affect Colonization of the Murine Urinary Tract by Escherichia coli CFT073

The urinary tract environment provides many conditions that deter colonization by microorganisms. D-serine is thought to be one of these stressors and is present at high concentrations in urine. D-serine interferes with L-serine and pantothenate metabolism and is bacteriostatic to many species. Uropathogenic Escherichia coli commonly possess the dsdCXA genetic locus, which allows them to use D-serine as a sole carbon, nitrogen, and energy source. It was previously reported that in the model UPEC strain CFT073, a dsdA mutant outcompetes wild type in the murine model of urinary tract infection. This “hypercolonization” was used to propose a model whereby UPEC strains sense D-serine in the urinary tract and subsequently up-regulate genes necessary for pathogenesis. Here, we show that inactivation of dsdA does not lead to hypercolonization. We suggest that this previously observed effect is due to an unrecognized secondary mutation in rpoS and that some D-serine specific effects described in other studies may be affected by the rpoS status of the strains used. Inactivation of dsdA in the original clinical isolate of CFT073 gives CFT073 ΔdsdA a growth defect in human urine and renders it unable to grow on minimal medium containing D-serine as the sole carbon source. However, CFT073 ΔdsdA is able to colonize the urinary tracts of CBA/J mice indistinguishably from wild type. These findings indicate that D-serine catabolism, though it may play role(s) during urinary tract infection, does not affect the ability of uropathogenic E. coli to colonize the murine urinary tract.     

Changes in Gut Flora after Cephalexin Treatment

Eighteen patients with urinary tract infection were treated with cephalexin orally. Absorption was variable, between 29 and 89% of the total daily dose being excreted in the urine in 24 hours. A significant number of patients became faecal carriers of Pseudomonas aeruginosa compared with a control group who received no antibiotics. Four of the cephalexin-treated patients acquired a strain of Ps. aeruginosa known to be present in food from the hospital diet kitchen and one developed a urinary tract infection with this strain.     

The problem of catheter encrustation

Catheter encrustation was studied in a group of long-stay hospital patients using both latex and silicone catheters. Moisture accounted for 80% by weight of the encrusted material with both catheters. Of the dry weight 90% was composed of protein, calcium, phosphorus, magnesium and uric acid. No relationship was found between the amounts of these substances in the urine and in the encrusted material. High levels of calcium, phosphorus and magnesium were found in the encrusted material from patients infected with Proteus organisms. No direct relationship was found between the duration of catheter drainage and the degree of encrustation, and there was a variation in patient susceptibility to encrustation irrespective of the catheter material. There was significantly less encrustation associated with silicone catheters.     

GC–MS determination of creatinine in human biological fluids as pentafluorobenzyl derivative in clinical studies and biomonitoring: Inter-laboratory comparison in urine with Jaffé, HPLC and enzymatic assays

In consideration of its relatively constant urinary excretion rate, creatinine in urine is a useful biochemical parameter to correct the urinary excretion rate of endogenous and exogenous biomolecules. Assays based on the reaction of creatinine and picric acid first reported by Jaffé in 1886 still belong to the most frequently used laboratory approaches for creatinine measurement in urine. Further analytical methods for creatinine include HPLC–UV, GC–MS, and LC–MS and LC–MS/MS approaches. In the present article we report on the development, validation and biomedical application of a new GC–MS method for the reliable quantitative determination of creatinine in human urine, plasma and serum. This method is based on the derivatization of creatinine (d₀-Crea) and the internal standard [methyl-trideutero]creatinine (d₃-Crea) with pentafluorobenzyl (PFB) bromide in the biological sample directly or after dilution with phosphate buffered saline, extraction of the reaction products with toluene and quantification in 1-μl aliquots of the toluene extract by selected-ion monitoring of m/z 112 for d₀-Crea-PFB and m/z 115 for d₃-Crea-PFB in the electron-capture negative-ion chemical ionization mode. The limit of detection of the method is 100 amol of creatinine. In an inter-laboratory study on urine samples from 100 healthy subjects, the GC–MS method was used to test the reliability of currently used Jaffé, enzymatic and HPLC assays in clinical and occupational studies. The results of the inter-laboratory study indicate that all three tested methods allow for satisfactory quantification of creatinine in human urine. The GC–MS method is suitable for use as a reference method for urinary creatinine in humans. In serum, creatine was found to contribute to creatinine up to 20% when measured by the present GC–MS method. The application of the GC–MS method can be extended to other biological samples such as saliva.     

Maintenance of dominance is mediated by urinary chemical signals in male European lobsters,Homarus gammarus

We studied the relevance of urine cues in Homarus gammarus dominance maintenance, hypothesising that urinary signals are necessary to mediate recognition of former opponents. Males in size-matched pairs interacted on two consecutive days with or without blocking urine release by adding catheters to both contestants on the second day. European lobsters established dominance in a first fight, and fight duration and aggression levels decreased strongly from first to second day in animals with free urine release, indicating the maintenance of this dominance relationship. If urine was blocked on the second day, fight durations were long in both first and second day interactions. Results demonstrate that urine signals contribute to the maintenance of dominance in H. gammarus males.     

The use of Opalina sudafricana in a biological test for diagnosing disordered metabolism of tryptophan in human subjects

Injections of urine of patients with bladder cancer linked with bilharziasis, simple urinary bilharziasis, ascariasis or ancylostomiasis, induced cyst formation found in Opalina sudafricana when injected into its host Bufo regularis. It is suggested that the carcinogenic tryptophan metabolites present in the injected urine reach the parasites in the recta of the experimental toads and stimulate them to divide mitotically to form small forms which eventually encyst. This test may be of a diagnostic help in detecting any abnormality in tryptophan metabolism in some human patients.     

Human Urinary Composition Controls Antibacterial Activity of Siderocalin

During Escherichia coli urinary tract infections, cells in the human urinary tract release the antimicrobial protein siderocalin (SCN; also known as lipocalin 2, neutrophil gelatinase-associated lipocalin/NGAL, or 24p3). SCN can interfere with E. coli iron acquisition by sequestering ferric iron complexes with enterobactin, the conserved E. coli siderophore. Here, we find that human urinary constituents can reverse this relationship, instead making enterobactin critical for overcoming SCN-mediated growth restriction. Urinary control of SCN activity exhibits wide ranging individual differences. We used these differences to identify elevated urinary pH and aryl metabolites as key biochemical host factors controlling urinary SCN activity. These aryl metabolites are well known products of intestinal microbial metabolism. Together, these results identify an innate antibacterial immune interaction that is critically dependent upon individualistic chemical features of human urine.     

Identification of urinary metabolites that distinguish membranous lupus nephritis from proliferative lupus nephritis and focal segmental glomerulosclerosis

Introduction

Systemic lupus erythematosus (SLE or lupus) is a chronic autoimmune disease, and kidney involvement with SLE, a.k.a. lupus nephritis (LN), is a frequent and severe complication of SLE that increases patient morbidity and mortality. About 50% of patients with SLE encounter renal abnormalities which, if left untreated, can lead to end-stage renal disease. Kidney biopsy is considered the criterion standard for diagnosis and staging of LN using the International Society of Nephrology/Renal Pathology Society (ISN/RPS) classification, which was developed to help predict renal outcomes and assist with medical decision-making. However, kidney biopsy-based classification of LN is highly invasive and impractical for real-time monitoring of LN status. Here, nuclear magnetic resonance (NMR) spectroscopy-based metabolic profiling was used to identify urinary metabolites that discriminated between proliferative and pure membranous LN as defined by the ISN/RPS classification, and between LN and primary focal segmental glomerulosclerosis (FSGS).

Methods

Metabolic profiling was conducted using urine samples of patients with proliferative LN without membranous features (Class III/IV; n = 7) or pure membranous LN (Class V; n = 7). Patients with primary FSGS and proteinuria (n = 10) served as disease controls. For each patient, demographic information and clinical data was obtained and a random urine sample collected to measure NMR spectra. Data and sample collection for patients with LN occurred around the time of kidney biopsy. Metabolic profiling analysis was done by visual inspection and principal component analysis.

Results

Urinary citrate levels were 8-fold lower in Class V LN compared to Class III/IV patients, who had normal levels of urinary citrate (P < 0.05). Class III/IV LN patients had > 10-fold lower levels of urinary taurine compared to Class V patients, who had mostly normal levels (P < 0.01). Class V LN patients had normal urinary hippurate levels compared to FSGS patients, who completely lacked urinary hippurate (P < 0.001).

Conclusions

This pilot study indicated differences in urinary metabolites between proliferative LN and pure membranous LN patients, and between LN and FSGS patients. If confirmed in larger studies, these urine metabolites may serve as biomarkers to help discriminate between different classes of LN, and between LN and FSGS.     

Type 1 Fimbriae Contribute to Catheter-Associated Urinary Tract Infections Caused by Escherichia coli

Biofilm formation on catheters is thought to contribute to persistence of catheter-associated urinary tract infections (CAUTI), which represent the most frequent nosocomial infections. Knowledge of genetic factors for catheter colonization is limited, since their role has not been assessed using physicochemical conditions prevailing in a catheterized human bladder. The current study aimed to combine data from a dynamic catheterized bladder model in vitro with in vivo expression analysis for understanding molecular factors relevant for CAUTI caused by Escherichia coli. By application of the in vitro model that mirrors the physicochemical environment during human infection, we found that an E. coli K-12 mutant defective in type 1 fimbriae, but not isogenic mutants lacking flagella or antigen 43, was outcompeted by the wild-type strain during prolonged catheter colonization. The importance of type 1 fimbriae for catheter colonization was verified using a fimA mutant of uropathogenic E. coli strain CFT073 with human and artificial urine. Orientation of the invertible element (IE) controlling type 1 fimbrial expression in bacterial populations harvested from the colonized catheterized bladder in vitro suggested that the vast majority of catheter-colonizing cells (up to 88%) express type 1 fimbriae. Analysis of IE orientation in E. coli populations harvested from patient catheters revealed that a median level of ∼73% of cells from nine samples have switched on type 1 fimbrial expression. This study supports the utility of the dynamic catheterized bladder model for analyzing catheter colonization factors and highlights a role for type 1 fimbriae during CAUTI.     

Arsenic concentration in the urine of patients with Blackfoot disease and Bowen’s disease

Extensive epidemiological study implicates that high arsenic content in artesian well water is the causal factor responsible for Blackfoot disease. We determine the arsenic concentration in urine samples of patients with Blackfoot and Bowen’s diseases and examine whether there exists any discrepancy of urinary arsenic concentrations among patients and the normal population. The analyses were made by hydride atomic absorption spectrophotometry (AAS) and the analytical reliability of the method was checked with a standard urine sample (ORTHO Bi-Level Urine Metal Control). The results show that the mean urinary arsenic concentration in 100 healthy adults is 63.4±29.7 μg/L, and those means for 23 and 11 patients with Blackfoot disease and Bowen’s disease are 75.7±39.1 μg/L (P vs controls >0.05) and 201±58 μg/L (P vs controls <0.001), respectively. From the analytical results obtained, we cannot conclude that urinary arsenic is associated with Blackfoot disease, as was disclosed from the epidemiological studies. However, urinary arsenic concentrations are possibly very closely associated with Bowen’s disease.