Comparison of isothermal microcalorimetry and BACTEC MGIT960 for the detection of the metabolic activity of Mycobacterium tuberculosis in sputum samples.

INTRODUCTION: This study explores the uses of microcalorimetry to detect Mycobacterium tuberculosis (TB) in sputum. Microcalorimetry measures metabolic heat evolution during cellular proliferation of tuberculosis (TB) and is considered as a possible alternative to conventional diagnostic tools. OBJECTIVES: To compare the time to detection (TTD) from the BACTEC™ MGIT™ 960 and the calScreener™ calorimetric system. METHODS: Sixty-four sputa samples were selected from patients with confirmed pulmonary tuberculosis. Those sample were then decontaminated and analysed using calorimetry and BACTEC MGIT 960 system. RESULTS: The incubation period until detection of M. tuberculosis in the sample was 8·5 ± 3·7 days for the MGIT system and 10·1 ± 4·1 days (mean ± SD) for calorimetry. CONCLUSIONS: The microincubations in the 48-well format calScreener offers potential for rapid and accurate diagnostic of TB in different samples. Although TTD from calorimetry is still longer than with the MGIT, our findings suggest that several improvements are possible. Still, the instrument is ideal for continuous, real-time analysis of net metabolic heat release of limited sample numbers. SIGNIFICANCE AND IMPACT OF THE STUDY: Our result emphasizes that with further optimization, calorimetry can become an alternative detection method for tuberculosis.

An alternative sterility assessment for parenteral drug products using isothermal microcalorimetry.

AIMS: Production and release of injectable drug solutions are highly regulated since the administration of injectables bypasses natural body barriers. The sterility test is the last opportunity of product quality assessment. However, sterility is currently assessed by visual inspection (VI) that is time consuming and somewhat subjective. Therefore, we assessed isothermal microcalorimetry (IMC) as a replacement for the VI of the filtration based state-of-the-art sterility control. METHODS AND RESULTS: We used ATCC strains and house isolates to artificially contaminate frequently produced monoclonal antibodies (Avastin, Mabthera, Herceptin). After filtration, growth was assessed with IMC. Growth of all micro-organisms was reliably and reproducibly detected 4 days after inoculation, which was significantly faster than with VI. CONCLUSIONS: The reliability and the sensitivity of IMC have a large potential to improve sterility controls. Further evaluation of this alternative method is therefore highly recommended. SIGNIFICANCE AND IMPACT OF THE STUDY: Drug safety is of great concern for public health. Faster and safer drug production could be achieved using the technique described here. All the tests were performed with real manufactured drugs and complied with pharmaceutical standards. This suggests that drug sterility testing can be improved with potentially increased safety and cost reduction.

Microcalorimetric assays for measuring cell growth and metabolic activity: methodology and applications.

Isothermal microcalorimetry measures the heat released or consumed by physical or chemical processes. Metabolic activity releases heat that can be measured. However the calorimetric signal can be difficult for new users to interpret. This paper compares microcalorimetry to other techniques and reviews its application to different fields where microbiological activity is important. We also describe different ways to analyze the data and translate it into meaningful (micro)biological equivalents. This paper aims at providing non-specialist reader the tools to understand how isothermal microcalorimetry can be used for microbiological applications.

Increasing prevalence of ciprofloxacin resistance in extended-spectrum-ß-lactamase-producing Escherichia coli urinary isolates.

PURPOSE: To describe the incidence and drug susceptibility profiles of uropathogenic extended-spectrum-ß-lactamase-producing Escherichia coli (ESBL-EC) during a 10-year period and to identify differences in resistance patterns between urological and non-urological ESBL-EC isolates. METHODS: Retrospective analysis of 191,564 urine samples obtained during 2001 to 2010 at the University Hospital Basel, Switzerland. The computerized database of the Clinical Microbiology Laboratory and the Division of Infectious Diseases and Hospital Epidemiology was used to identify ESBL-EC positive urine samples. ESBL-EC isolates were stratified according their origin into two groups: Urology and non-Urology isolates. RESULTS: The rate of ESBL-EC positive urine samples increased significantly during the study period (3 in 2001 compared to 55 in 2010, p < 0.05). The most active agents were imipenem, meropenem, and fosfomycin (100%), followed by amikacin (99.1%) and nitrofurantoin (84%). The least active substances were ampicillin-clavulanate (20%), sulfamethoxazole (28%), and ciprofloxacin (29.6%). ESBL-EC isolates from urological and non-urological patients showed similar susceptibility profiles. However, ESBL-EC isolates from urological patients were significantly less susceptible to ciprofloxacin compared to non-urological isolates (14.7 vs. 32.7%, p < 0.05). CONCLUSIONS: The rate of urinary ESBL-EC isolates is increasing. Their susceptibility to nitrofurantoin, fosfomycin, and carbapenems is excellent, whereas ampicillin-clavulanate, sulfamethoxazole, and ciprofloxacin demonstrate only low susceptibility. In particular, the use of ciprofloxacin should be strictly avoided in urologic patients with suspicion for an ESBL-EC urinary tract infection as well as routine antibiotic prophylaxis prior to urological interventions if not explicit indicated by current international guidelines or local resistance patterns.

Comparison of the roll-plate and sonication techniques in the diagnosis of microbial ureteral stent colonisation: results of the first prospective randomised study.

BACKGROUND: Microbial ureteral stent colonisation (MUSC) is one leading risk factor for complications associated with ureteral stent placement. As MUSC remains frequently undetected by standard urine cultures, its definitive diagnosis depends on microbiological investigation of the stent. However, a standard reference laboratory technique for studying MUSC is still lacking. MATERIALS AND METHODS: A total of 271 ureteral stents removed from 199 consecutive patients were investigated. Urine samples were obtained prior to device removal. Stents were divided into four parts. Each part was separately processed by the microbiology laboratory within 6 h. Ureteral stents were randomly allocated to roll-plate or sonication, respectively, and analysed using standard microbiological techniques. Demographic and clinical data were prospectively collected using a standard case-report form. RESULTS: Overall, roll-plate showed a higher detection rate of MUSC compared with sonication (35 vs. 28 %, p < 0.05) and urine culture (35 vs. 8 %, p < 0.05). No inferiority of Maki's technique was observed even when stents were stratified according to indwelling time below or above 30 days. Compared with roll-plate, sonication commonly failed to detect Enterococcus spp., coagulase-negative staphylococci (CoNS) and Enterobacteriaceae. In addition, sonication required more hands-on time, more equipment and higher training than roll-plate in the laboratory. CONCLUSIONS: This prospective randomised study demonstrates the superiority of Maki's roll-plate technique over sonication in the diagnosis of MUSC and that urine culture is less sensitive than both methods. The higher detection rate, simplicity and cost-effectiveness render roll-plate the methodology of choice for routine clinical investigation as well as basic laboratory research.

Use of isothermal microcalorimetry to quantify the influence of glucose and antifungals on the growth of Candida albicans in urine.

AIMS: Urinary tract infection (UTI) caused by Candida spp. is an increasing problem in clinical practice. Risk factors include diabetes mellitus, extremes of age, urinary tract abnormalities and indwelling catheters. Here, we determined the applicability of isothermal microcalorimetry (IMC) for the detection and antifungal drug susceptibility testing of Candida albicans in artificial urine. METHODS AND RESULTS: Isothermal microcalorimetry was used to monitor the metabolic heat production rates of C. albicans at 37 °C (µW = µJ s(-1) ). The influence of increasing concentrations of glucose and antifungal drugs on the growth of C. albicans was investigated. The growth rate increased linearly from 0.024 ± 0.010 to 0.203 ± 0.006 h(-1) with increasing concentration of glucose from 20 to 1640 mg l(-1) . The minimum inhibitory concentrations (MIC) against C. albicans were determined at a fixed glucose concentration of 560 mg l(-1) . These MIC were 0.5 µg ml(-1) for amphotericin B, 5 µg ml(-1) for flucytosine, 0.8 µg ml(-1) for fluconazole and 0.5 µg ml(-1) for tioconazole, respectively. CONCLUSIONS: IMC is able to detect and quantify growth of C. albicans in artificial urine and to determine the MIC of antifungal drugs against C. albicans. This study demonstrated that IMC can be used for basic research on Candida-UTI and opens promising avenue for the use of IMC as rapid drug resistance screening tool and diagnostic tool. SIGNIFICANCE AND IMPACT OF STUDY: Little is known on the growth of C. albicans in urine. Our study provides measurements of the growth rate of this yeast in urine with various glucose concentrations. Thus, important insights are gathered for risk group such as patients with diabetes or patients with prolonged parenteral nutrition resulting in higher urinary glucose concentration.

Stents and stone disease.

The use of stents in renal stone disease is relatively new. The main advantage is reduced pressure in the renal collecting system during times of infected obstructed collecting systems, surgery or obstructing stones. As much pain relieve theses stents offer when indicated, equally much morbidity is caused when stent materials interface with the human urothelium in terms of symptoms, perforations and the "forgotten stent". This review aim to summarize some of the most important considerations when stents are used in stone disease.

[Prostate biopsy-infection prophylaxis and patient preparation]. / Prostatabiopsie ­ Infektionsprophylaxe sowie Vorbereitung des Patienten.

Prostate biopsy has been at the center of controversy in recent years due to high infection complications associated with the transrectal route and the withdrawal of authorization for fluoroquinolones and fosfomycin trometemol as prophylaxis. The Urological Infections Guideline Group of the European Association of Urology (EAU) recently published a meta-analysis in two parts based on randomized controlled trials (RCTs) and annually updates the data for the EAU guidelines. The meta-analyses show that transperineal prostate biopsy is associated with significantly fewer infectious complications than transrectal biopsy and should therefore be preferred. If transrectal biopsy is still used, then intrarectal cleansing with povidone-iodine and antibiotic prophylaxis should be used. Antibiotic prophylaxis strategies include targeted prophylaxis after sensitivity testing of the rectal flora, augmented prophylaxis with several antibiotics and empirical monoprophylaxis. Data from RCTs are available for aminoglycosides and third-generation cephalosporins.

Microbial ureteral stent colonization in renal transplant recipients: frequency and influence on the short-time functional outcome.

Ureteral stent insertion at the time of renal transplantation significantly decreases complications of urine leakage and obstruction, but bears an intrinsic risk of microbial colonization. Associated urinary tract infection (UTI) may pose a significant risk for graft infection and subsequent graft failure, in particular, during high-level immunosuppression in the early phase after transplantation. The aims of this prospective study were (i) to assess the frequency of microbial ureteral stent colonization (MUSC) in renal transplant recipients by sonication, (ii) to compare the diagnostic value of sonication with that of conventional urine culture (CUC), (iii) to determine biofilm forming organisms, and (iv) to investigate the influence of MUSC on the short-time functional outcome. A total of 80 ureteral stents from 78 renal transplant recipients (deceased donors n = 50, living donors n = 28) were prospectively included in the study. CUC was obtained prior to renal transplantation and at ureteral stent removal. In addition, a new stent sonication technique was performed to dislodge adherent microorganisms. CUCs were positive in 4% of patients. Sonicate-fluid culture significantly increased the yield of microbial growth to 27% (P < 0.001). Most commonly isolated microorganisms by sonication were Enterococcus species (31%), coagulase-negative staphylococci (19%), and Lactobacillus species (19%), microorganisms not commonly observed in UTIs after renal transplantation. The median glomerular filtraton rate (GFR) of the study population increases from 39 mL/min immediately after transplantation (time point A) to 50 mL/min 6 month post transplantation (time point B). In patients without MUSC, the GFR improves from 39 mL/min (A) to 48 mL/min (B) and in patients with MUSC from 39 mL/min (A) to 50 mL/min (B), respectively. In summary, MUSC in renal transplant recipients is common and remains frequently undetected by routine CUC, but colonization had no measurable effect on renal function.

[Infectious complications following prostate biopsy-Major changes 2020]. / Infektionskomplikationen bei Prostatabiopsie 2020 ­ Was hat sich geändert?

BACKGROUND: Infectious complications following prostate biopsy are increasing and fluoroquinolone prophylaxis has recently been suspended in Germany by the national authorities. OBJECTIVES: This review is intended to highlight current strategies for reducing infectious complications following prostate biopsy. MATERIALS AND METHODS: The European Association of Urology (EAU) guideline group on urological infections recently published a meta-analysis in two parts based on randomized controlled trials (RCTs). The most important contents shall be presented here. RESULTS: Transperineal prostate biopsy is associated with significantly reduced infectious complications than transrectal biopsy. If transrectal biopsy is performed, intrarectal cleaning with povidone-iodine and antibiotic prophylaxis without fluoroquinolones should be chosen. Antibiotic prophylactic strategies include targeted prophylaxis after susceptibility testing of the rectal flora, augmented prophylaxis with multiple antibiotics and empiric monoprophylaxis with nonfluoroquinolones. Here data from RCTs are available for aminoglycosides, third generation cephalosporines, and fosfomycin trometamol. CONCLUSIONS: The transperineal approach is preferred to reduce prostate biopsy-related infections. Fluoroquinolones are no longer approved for prophylaxis. Thus, alternative antibiotics based on local resistance, or targeted prophylaxis, in conjunction with povidone-iodine rectal preparation are recommended for transrectal prostate biopsy.

[Urological infections and migration]. / Urologische Infektionen und Migration.

In the context of refugee migrations infectious diseases are being more frequently diagnosed, which the responsible physicians as well as urologists have never seen before. This is due to the poorer health and hygiene conditions in the country of origin, during the flight and in the refugee camps. In Europe increasing incidences of tuberculosis, schistosomiasis and scabies have recently been observed. Tuberculosis and schistosomiasis are often accompanied by unspecific symptoms or can resemble normally encountered urological diseases. Due to the highly contagious nature of scabies, a screening of new arrivals is recommended. A timely differential diagnostic inclusion of these disease patterns is enormously important. Despite the reduction in the numbers of asylum applications in Germany, a higher number of unregistered migrants is generally assumed, who also elude the healthcare system and can therefore contribute to the spread of these rare infectious diseases.

[Syphilis and Henry VIII : A disease writes world history]. / Syphilis und Heinrich VIII. : Eine Erkrankung schreibt Weltgeschichte.

Syphilis is a chronic sexually transmitted disease (STD). At the end of the 15th century, Christopher Columbus imported it as "a souvenir" from his first voyage of discovery. The disease met a weakened and not yet infected population. The disease quickly engulfed all of Europe. The course of the disease was much more dramatic than it is today. Even royal houses were not spared. Using the example of Henry VIII of England this article briefly outlines the influence of syphilis both to the house of Tudor and thus on the big political stage.

[Benign space-occupying cysts in the testis. An overview]. / Benigne zystische Raumforderungen des Hodens. Eine Ubersicht.

Testicular cysts are increasingly diagnosed in the course of scrotal ultrasound examination. Among other things this is due to the general availability of modern high-resolution ultrasound devices. Benign and malignant diseases with testicular cyst formation need to be differentiated by differential diagnosis and by their aetiology. Benign diseases with cystic space-occupying lesions of the testicle are tubular ectasia of the rete testis, cystic dysplasia, epidermoid cysts, simple intraparenchymatous testicular cysts and cysts of the tunica albuginea. Testicular dermoid cyst was long misleadingly regarded as potentially malignant, but is now classified as benign. On diagnosis of a benign lesion of the testis an organ-conserving surgical therapy or an observational watch-and-wait strategy can be recommended in most cases.

[New microbiological techniques]. / Neue mikrobiologische Techniken.

Microbiological diagnostic procedures have changed rapidly in recent years. This is especially true in the field of molecular diagnostics. Classical culture-based techniques are still the gold standard in many areas; however, they are already complemented by automated and also molecular techniques to guarantee faster and better quality results. The most commonly used techniques include real-time polymerase chain reaction (RT-PCR) based systems and nucleic acid hybridization. These procedures are used most powerfully from direct patient samples or in assays to detect the presence of nonculturable or fastidious organisms. Further techniques such as DNA sequencing are not yet used routinely for urological samples and can be considered experimental. However, in conjunction with dropping prices and further technical developments, these techniques promise to be used much more in the near future. Regarding bacterial identification from culture, mass spectrometry (MALDI-TOF MS) has become the technique of choice in recent years especially in Europe. It has tremendously shortened the time to result. This is now going to be extended to antibiotic susceptibility testing. This is of paramount importance in view of ever rising antimicrobial resistance rates. Techniques described in this review offer a faster and better microbiological diagnosis. Such continuous improvements are critical especially in times of cost pressure and rising antimicrobial resistance rates. It is in our interest to provide the best possible care for patients and in this regard a good and effective communication between the laboratory and the clinician is of vital importance.

[Urinary Tract Infections--Current Innovations in Urine Diagnostics]. / Harnweginfektionen - Aktuelle Neuerungen in der Urindiagnostik.

Urine culture (UC) confirms the diagnosis of urinary tract infection (UTI) and is still considered the diagnostic 'gold standard' for pathogen identification, quantification and resistance testing. However, up to 80% of samples will not yield bacterial growth. Different techniques are currently approved for resistance testing. However, all of them are culture based and have the disadvantage of being very slow. In the field of urology, the development of drug resistance of uropathogens complicates the optimal administration of antimicrobial agents not only in the treatment, but also in the prevention of UTI before endourological and open surgical procedures. In this context, rapid identification of microbiological agents, including timely antimicrobial resistance testing (ART) is desirable. This overview presents alternative techniques (flow cytometry, PCR-based techniques, MALDI-TOF MS and microcalorimetry) to urine culture and discusses their advantages and disadvantages.

[Renal aspergilloma: retroperitoneoscopic resection as a minimally invasive organ preservation treatment option]. / Renales Aspergillom: Retroperitoneoskopische Exzision als minimal-invasive organerhaltende Therapieoption.

Aspergillus infections frequently affect immunocompromised patients and are associated with high mortality. We report the case of a renal aspergilloma in a bone marrow transplant recipient. Treatment is challenging and requires a combination of systemic antifungal therapy and surgery. In the present case, a minimally invasive retroperitoneoscopic resection of the aspergilloma was performed.

[Areas of application of isothermal microcalorimetry in urology: an overview]. / Anwendungsbereiche der isothermalen Mikrokalorimetrie in der Urologie : Eine Übersicht.

Isothermal microcalorimetry (IMC) is a nonspecific analytical tool for measurement of heat. With sensitivity in the order of 0.2 µW, IMC can detect very small amounts of heat produced by only a small number of microorganisms or eukaryotic cells. This report is intended to introduce IMC to the urological audience and to give an overview about the past, present and future of this cutting edge technology in the urological context.