UTI Screening: Molecular Diagnostics Vs Urine Culture

UltimateDx specializes in molecular diagnostic testing. Our focus on infectious disease coupled with molecular diagnostic elevates our laboratory services. We offer comprehensive pathogen detection as well as identifying antibiotic resistance through gene amplification and analysis. UltimateDX’s laboratory capabilities puts us at the forefront of diagnostic services. Very few commercial laboratories are able to provide comprehensive, accurate, and timely results through the use of molecular genetics.

UTI screening is an area of focus for our laboratory. The use of molecular diagnostics has shown substantial benefits to conventional UTI screening used through culturing.

Culture vs Molecular UTI Screening:

Turn-around time:

Standard bacteria cultures can take up to 3 days to show results. This high turn-around time can lead to antibiotic resistance and interfere with the ability to prescribe the right medication. Molecular diagnostics can show results within hours. The use of Real-Time PCR analysis allows for our lab to correctly analyze pathogenic genetic components to improve the accuracy of results. Our laboratory technicians are well trained in PCR techniques for molecular diagnostics in order to provide results from 12-24 hours of receiving the sample. Not only is our use of molecular genetics a faster and more accurate way of detecting pathogens, but it is a more precise way to provide reports to physicians to allow for better treatment plans.

Accuracy of Results:

Culture growth is dependent on the microbial presence within a sample. This causes difficulty when culturing samples to provide results. Sometimes the microbial presence is not enough to provide accurate results through culturing. Since UTI screening is done through specimen samples, it would need to be done within hours of the sample being collected. The samples need to be cultured in a timely manner to avoid false-positive results that can skew the overall diagnosis. Molecular diagnostic techniques however, are not dependent on the volume of microbial presence. This is because we are able to extract the DNA of any microbios that are present in the sample with great sensitivity and accuracy.

Co-Infection Sensitivity and Specificity:

It is not uncommon for conventional culture analysis to miss pathogens. This is due to the barriers of specificity that are present when culturing a sample. Cultures do not have the ability to isolate samples with more than two pathogens. Co-infection is a crucial part of diagnosing a sample, but cultures cannot provide results that differentiate more than one to two different microorganisms. This can also result in antibiotic resistance to certain pathogens that may not be detected through culturing. Conversely, molecular diagnostic techniques, such as PCR, allow for us to detect pathogens with much more pathogen sensitivity and specificity. This means that we are able to isolate the genetic components of a variety of microbes that are present within a sample. Not only are we able to identify co-infected specimens, but we are able to classify which pathogens are present in low volumes and in high volumes. Specifically in UTI screening, PCR is used to detect both the presence of bacteria and yeast in one test. This can be compared to traditional culturing’s need to use two separate cultures to identify bacteria and yeast independently.

	Urine Culture	Molecular Diagnostics
Faster Turn-around time
Sensitivity and accuracy in Test Result
Highly Specific and Sensitive Co-Infection

UTI Culture Screening:

Takes 3-5 days to complete (can lead to antibiotic resistance)
Specificity and sensitivity are compromised due to the inherent risk of missing pathogens within a culture.
Culture growth is dependent on microbial load within a sample (can cause false-negative results and prevent culture growth)
Results are skewed after hours of sample collection (the longer the sample sits, the more variable the pathogen presence is)
Cannot detect co-infection with accuracy (can only detect 1-2 microorganisms)

UTI Molecular Diagnostic Screening:

Can be completed with accurate results within hours
UTI pathogens are detected with greater accuracy (pathogen DNA is identified to show the presence of the exact pathogen)
Results are dependent on DNA presence of pathogens as opposed to the volume of microbes in the sample.
High specificity and sensitivity allows for detection of co-infections with numerous pathogens, and even low microbial presence
Reports antibiotic resistance to help physicians diagnose and treat patients accurately and efficiently.

Urinary Tract Infections:

UTI’s are also known as urinary tract infections. They are a result of bacteria that can go to any part of your urinary system including your kidneys, bladder, ureters, and urethra. UltimateDX uses PCR analysis to detect resistance markers and cultures to identify pathogen colonization.
Problems with UT Identification:
1. UTIs have always been difficult to diagnose. Symptoms may be vague and can be seen in a variety of ailments. It has been shown that a typical UTI culture can miss up to 75% of UTI diagnosis. This means that due to the inaccuracy of cultures, many patients have inaccurate diagnoses that can have dangerous consequences.
2. Mutli-Drug Resistant Organisms are microorganisms that develop resistance to medication such as antibiotics. As bacteria multiply and proliferate, they develop resistance to antibiotics. This has made treatment of UTIs much more difficult for physicians. This illustrates the importance of accurate diagnostic practices in order to give the right antibiotics to the right individuals. Individuals that show the presence of Multi-Drug Resistant Organisms must not be given antibiotics that cannot interact with the infection. Similarly, individuals who take antibiotics due to false-positive results can develop antibiotic resistance, which will be much more difficult to treat in the future.
UTI Pathogen Detection:
- Candida species
- Proteus mirabilis
- Klebsiella pneumoniae
- Morganella moranii
- Serratia marescens
- Klebsiella oxytocai
- Enterobacter cloacae
- Providence suartii
- Pseudomonas aeruginosa
- Streptococcus agalactiae
- E. coli
- Citobacter freundii
- Staphylococcus aureus
- Staphylococcus saprophyticus
- Enterococcus faecalis
- Ureaplasma urealyticum
- Mycoplasma hominis
Symptoms: While UTI’s can be asymptomatic, infected individuals may experience a strong urge to urinate, burning sensation during urination, small amounts of urine passing, cloudy urine, bloody urine, or pain in the pelvic region.
Causes and Risk factors: UTI’s are most common among women. The most common region to be infected is the bladder, which is known as cystitis. This infection is caused by E.Coli, which is found throughout the GI tract which can be easily exposed to the urethra.
Treatments and Prevention: In order to prevent UTI development, it is essential to drink plenty of fluids. Some fluids such as cranberry juice have been known to be a novel way to prevent UTI’s. It is important to maintain genital hygiene and limit the exposure of bacteria from the anus. It is also critical to urinate after sexual intercourse to flush out any bacteria that may have come in contact with the urethra.