The urinary tract is the most common site of nosocomial infections  and urinary tract infections account for approximately 40% of all hospital-acquired infections in the United States . Most of the urinary tract infections are associated with an indwelling urinary catheter . Referred to as Catheter Associated UTI (CA-UTI) these infections cause substantial morbidity in both men and women and is a preventable patient safety issue. In 2007, the Center for Disease Control, USA reported 139,000 CA-UTI cases  resting in a massive increase of the medical cost (131 million USD) . It has been long acknowledged that CA-UTI is the most common infection type in Intensive care units. In a study that provided the national estimate of Healthcare- associated infections in the US, urinary tract infections comprised 36% of the total Healthcare- associated infections estimate. (Figure 1) 
CA-UTI is complex and alters the body’s ability to eradicate bacteria in the lower urinary tract, leading to urosepis and septicemia. The infection is often associated with long-term catheter use. CA-UTIs may occur atleast twice a year in patient with indwelling catheters and usually require hospitalization. Other adverse outcomes of CA-UTI include prolonged hospital stay, secondary bacteremia/ sepsis, increased mortality, late onset sequellae, formation of urinary encrustations and obstruction to flow, multidrug resistance, urethral strictures, prostatitis and orchitis.  Deadly consequences of the disease demand effective identification, management and prevention strategies.
Therefore, Pseudomonas, Serratia, coagulase-negative Staphylococci, Acinetobacter and other non-intestinal or environmental microbes can result in CA-UTI. [9, 10] These bacteria can ascend to the urinary tract via either the external or internal surface of the catheter. External bacterial ascension occurs due colonization of bacteria on the surface of the catheter (often creating biofilms), after one to three days of catheterization. Internal bacterial ascension occurs as bacteria tend to be introduced when opening the otherwise closed urinary drainage system.  Hence, accurate, rapid and sensitive identification of disease aetiology helps in establishing efficient disease management measurements.Many strains endogenous intestinal flora; including Escherichia coli, Enterobacter, Klebsiella, Enterococci, and Proteus act as common pathogens of the urinary tract and potential colonizers of urinary catheters. In addition, inadequately decontaminated equipment and hands of healthcare workers may introduce environmental and common skin bacteria during insertion or maintenance of the urinary catheter.
However, current disease identification practices are entirely dependent on conventional techniques. These techniques include culturing, colony counting and gram staining of samples as well as non- culture based methods such as urine microscopy, biochemical testing (nitrate tests, leukocyte esterase tests).  Although culture methods are considered as gold-standard, have major drawbacks which intervene with identification procedures, and may often generate uncertain or erroneous results. Result generation is usually time –consuming, with results taking 7-10 days to receive. In addition, fastidious growth requirements or unculturable organisms, unusual biochemical reactions or lack of previous data impede culture based identification methods. The urine Gram stain test has the important advantage of providing immediate information as to the nature of the infecting bacterium, but disadvantages such as insensitivity (identification is reliable only if the concentration of bacteria in the urine is ≥105 CFU/ml; infections with bacterial concentrations of 102–103 CFU/ml may not be detected by this test) and tediousness limit its usefulness in most clinical settings.  Biochemical processes based on identification of chemicals produced by bacteria, fail to detect certain urinary tract pathogens in the absence of desired chemical production (e.g.,nitrite production is not associated with urinary-tract pathogens such as S. saprophyticus, Pseudomonas species, or enterococci ) .
Drawbacks of conventional methods may lead to adverse health conditions in CA- UTI patients. Without timely results from a urine culture, patients may experience complications, prolonged infections, increased hospitalization and, potentially, death. Over prescription of antibiotics increases the potential for creating resistant strains of bacteria. Due to these factors, it is apparent that an accurate, rapid, sensitive tool for diagnosis of CA-UTI is needed. Healthcare providers are therefore moving towards faster, reliable identification methods that deliver accurate and highly sensitive data with higher transparency.
Sequence based identification of 16s rRNA gene of pathogenic bacteria is a rapid, novel method that facilitate the fast identification of microbial pathogens causing Catheter-Associated Urine Tract Infections. This test, known as BactFast is made available in Sri Lanka by Credence Genomics for the very first time. With the availability of BactFast, the causative organisms can be identified faster, consequently accelerating the antimicrobial therapy. Deep knowledge on the presence of specific organisms with certainty narrows down the treatment scope, focusing on elimination of the causative organisms unlike in earlier techniques.
BactFast is clearly a life saving approach due to its rapid turnaround time – it only requires a turnaround time of 48 hours. In contrast to conventional techniques such as plating, pathological or histological analysis which consist of time- consuming, cumbersome, error prone protocols BactFast®, delivers safest, most accurate and sensitive results allowing faster identification of pathogenic bacteria. The technique is capable of identifying the entire spectrum of known pathogens present in a sample within a single run making BactFast® the only test of its kind. In addition, the technique facilitates identification of intragenic variations among closely related species, while determining the relative abundance of each strain within the population.
BactFast® provides a vast range of opportunities to resolve a number of issues that burdens the healthcare system. Early detection of the disease helps the physicians to identify the course of therapy before the infection worsens and continuous medication procedures can minimize the disease complexity. It also helps to minimize the cost spent on antibiotics and additional medical care while reducing the tendency of developing antibiotic resistant microbial strains that could affect the patient’s life in long term. Moreover, it greatly reduces the hospital stay while decreasing the tendency of administration of non- specific drugs that could adversely affect other underlying diseases, imposing life threatening situations. With the exact etiology of CA-UTI being revealed with sequenced base 16s rRNA gene analysis, significantly effective disease preventive measures as well as increased sanitary conditions can be established at Intensive Care Units, in turn reducing the prevalence rate of this deadly hospital- acquired infection.
Following is a comparison between BactFast and conventional methods of diagnosis of CA-UTI
|Conventional methods of CA-UTI diagnosis||BactFast®|
|Immune-compromised patients at ICUs require fast identification of disease etiology.Culture based identification requires a minimum turnaround time of 7-10 Days, which subsequently delays the antimicrobial therapy.||Very short turnaround time. Generates results within 21 hours.Patients can be administered with specific antimicrobial therapy.|
|Delayed identification process can be life threatening for immune compromised patients.||Fast identification, Clearly a life saving approach.|
|Results can be non-specific and error prone and may contain a specific degree of uncertainty.||Results are highly accurate, sensitive and entirely reliable.|
|May often lead to overuse or misuse of antibiotics that helps in developing antibiotic resistant strains of bacteria.||No overuse or misuse of antibiotics. No drug abuse that may end up in adverse effects. Maximum treatment efficacy.|
|Results in Prolonged hospital stays.Increased cost of hospitalization||Reduces the cost of hospitalization by greatly cutting down the requirement of prolonged hospital stay.|
|Increased cost on antibiotics and other relevant medical care.||Reduces the cost on antibiotics and medical care.|
|Results in high rates of mortality and morbidity.||Lowers morbidity and mortality rates.|
|Does not permit to identify intragenic variations and relative abundances of identified organisms.||Intragenic variations among species and their relative abundances can be identified. This allows further analysis of test organisms.|
|Culture based techniques are often hindered by non-culturable organisms, fastidious growth requirements, unusual biochemical reactions, morphological variations and lack of previous data.||BactFast® is culture independent. Diagnosis is never affected by external factors.|
|Number of organisms identified per test is always a limiting factor.||Can identify the entire spectrum of microorganisms in a single test. Unlimited test scope.|
|Some clinical methods used in identification of VAP can be aggressively invasive.||BactFast® is an entirely safe, non-invasive technique.|
- Klevens RM, Edward JR, Richards CL, et al. “Estimating Healthcare Associated infections and deaths in U.S. hospitals,2002”.Public Health Rep.2007;122(2):160-166
- Kunnin CM. “Nosocomial urinary tract infections and the indwelling catheter: what is new and what is true?” Chest.2001; 120(1):10-12
- Anderson DJ, Kirkland KB, Kaye KS. et al “Underresourced hospital infection control and prevention programmes: penny wise, pound foolish?” Infection control hospital epidemiology.2007;28(7);767-773
- Wise M. Burden of major hospital-onset device-associated infection types among adults and children in the United States, 2007. 21st Annual Scientific Meeting of the Society of Healthcare Epidemiology of America.2011.
- Burton, Deron C., et al. “Trends in catheter-associated urinary tract infections in adult intensive care units—United States, 1990–2007.” Infection Control and Hospital Epidemiology8 (2011): 748-756.
- Klevens, R. Monina, et al. “Estimating health care-associated infections and deaths in US hospitals, 2002.” Public health reports2 (2007): 160.
- Newman, DIANE K. “Prevention and management of catheter-associated UTIs.”Infect Dis(2010): 13-20.
- Kunin, Calvin M. Urinary tract infections. Detection, prevention, and management. No. Ed. 5. Williams & Wilkins., 1997.
- Greene, L., J. Marx, and S. Oriola. “Guide to the elimination of catheter-associated urinary tract infections (CAUTIs).” APIC(2008).
- Tambyah, Paul A., Valerie Knasinski, and Dennis G. Maki. “The direct costs of nosocomial catheter-associated urinary tract infection in the era of managed care.” Infection control and hospital epidemiology2002(23.1): 27-31.
- Rebmann, Terri, and Linda R. Greene. “Preventing catheter-associated urinary tract infections: An executive summary of the Association for Professionals in Infection Control and Epidemiology, Inc, Elimination Guide.” American journal of infection control8 (2010): 644-646.
- Mancini, Nicasio, et al. “The era of molecular and other non-culture-based methods in diagnosis of sepsis.” Clinical microbiology reviews1 (2010): 235-251.