At present, medical diagnosis includes multiple examinations that allow for better precision and more positive patient outcomes. Probably, the most significant tests that help with differential diagnosis are blood and urine tests. As seen from the term, blood test is a scientific test that examines a blood sample, typically for the purposes of diagnosis or detection of the presence of drugs or other substances. Urine test investigates the appearance, concentration and content of a patient’s urine for the same purposes: either differential diagnosis or substance detection. This report discusses the history of urine toxicology and blood testing and their use in modern medicine. Aside from that, this paper outlines the barriers to successful testing as well as advantages and disadvantages of the method.
History and Purpose
The history of blood testing started in 1901 when an Austrian biologist and immunologist Karl Landsteiner put forward a proof of the existence of three blood types – A, B, and C (later renamed to O) (Castiglioni, 1). In 1902, Landsteiner’s colleagues, Alfred Decastello and Adriano Sturli, discovered AB as the fourth and the final blood type. The scientists’ discovery was a breakthrough in the world of medicine. While it had been long recognized that human blood composition varied from person to person, Landsteiner was able to show that human blood is not universally compatible. The second greatest breakthrough, also made by Landsteiner, was in 1939 when the biologist discovered the Rh factor in blood. Landsteiner’s contributions to medicine made blood transfusions immensely safer as now it was possible to test for both type and factor.
Around the same time, in the 1930-1940s, testing for bloodborne diseases became the norm in American society (Castiglioni, 1). Actually, in most states, it was mandatory to have a clean bill of health after testing for syphilis and/or rubella to obtain a marriage license in those days. Thanks to blood testing, spouses-to-be could receive the necessary treatment before infecting each other or endangering the health of their future children. 1971 was marked with the first blood test for 1971, and fast forward to 1985, the world saw the first HIV test. Today, the Red Cross performs more than ten tests on all blood donations to enable safe transfusion.
The history of urinalysis dates back to the ancient world. It is believed that Hippocrates was the original uroscopists, though there is evidence that urine diagnosis pre-dates him (Castiglioni, 1). Some important breakthroughs in the history of urinalysis include the discovery of the protein, Albuminuria, in 1694. In the same century, the advent of the microscope made it possible to analyze urine sediments. Starting from 1827, per the initiative of the English physician Richard Bright, urine examination became a routine examination for all patients. The 1970-1980s were marked with popularization of urine drug testing which was first done in the military and then became commonplace in the corporate environment.
Step by Step Procedures
Blood test starts with blood collection: blood is typically drawn from the vein on the outer portion of the arm next to the elbow, using a needle. After drawing blood, a laboratory worker labels the sample, using a unique patient identification number or a barcode. The next step is documentation: once the lab receives a specimen, it is logged into its tracking system. Documentation helps to ensure that the blood sample will undergo all the necessary tests and the results will be matched with the patient’s name. Depending on the type of test needed, it might be necessary to process blood as most routine blood tests are administered on either plasma or serum (Chernecky and Berger 2). In most cases, blood testing is automated, and modern blood analyzers can process rather large batches of blood simultaneously.
For urinalysis, patients are given clear cups to urinate into at the doctor’s office, hospital, or specialized facility (patients are given privacy while doing it). It is recommended to clean the genital area before urinating so that urine samples are turned in clean. After urine is collected, a doctor or a laboratory worker administers some or all of the following tests. As the name suggests, a microscopic exam is done with the help of a microscope; it helps to detect abnormalities in a patient’s red or while blood cells, kidney disease, or bladder cancer. A dipstick test involves inserting a chemically treated stick into a urine sample, which helps to detect the presence of bilirubin, blood, protein, sugars, and other compounds (Chernecky and Berger 2). Both urine and blood tests end with communicating results to the patient and giving further instructions and recommendations.
Use of Urine Toxicology and Blood Testing
Urinalysis and blood tests are able to disclose the evidence of many diseases and the presence of substances such as drugs. They are particularly useful for diagnosing conditions that do not show clear signs or symptoms. For this reason, blood and urine tests make a part of a routine health check for all patients. Urinalysis helps with the diagnosis of infections related to a urinary tract or kidneys and identification of causes of kidney failure. Urine tests results may also be reflective of the progression of chronic conditions such as diabetes mellitus and high blood pressure (hypertension). National Heart, Lung, and Blood Institute (3) provides a list of what modern blood tests are able to show, which includes but is not limited to:
- Kidneys, liver, thyroid, and heart function;
- Diseases such as Cancer, HIV/AIDS, diabetes, anemia, and coronary heart disease;
- Risk factors for heart disease;
- Effectiveness of a treatment plan.
Barriers to Successful Testing
In primary care, testing and result communication often face barriers. Their successful completion is contingent on the coordination of efforts of medical staff at a given facility. Litchfield et al. (4) identified a total of six areas of growth that medical facilities should be paying more attention to:
- delayed phlebotomy;
- lack of a fail-safe to make sure that blood tests return from the laboratory;
- difficulties in evaluating results by telephone;
- the role of non-medical staff in communicating results. Litchfield et al. (4) note that both patients and healthcare workers were skeptical and cautious of receptionists communicating results. Receptionists are considered to be unable to answer further questions about blood and urine tests;
- communicating normal results have been found a waste of resources by some respondents;
- lack of a standardized protocol.
Advantages and Disadvantages
The main advantage of blood testing and urine toxicology is their helpfulness with detecting abnormalities and making diagnosis. Blood and urine tests are routine procedures that do not cause much discomfort in patients and yield fast, highly interpretable results. What is more, a great number of conditions are largely asymptomatic and only manifest themselves once a patient approaches a critical stage where their health quickly deteriorates. Routine testing promotes proactivity in health care that focuses on prevention rather on handling the consequences (Faiella et al., 5).
On the other hand, there is usually an interval of acceptable accuracy, which means that some results prove to be false positive – as in, they mistakenly detect a disease or a substance. The accuracy of tests has grown to be a major problem amidst the chaos of the COVID-19 pandemic. Deeks et al. (6) report that the existing COVID-19 antibody tests are mostly reliable; however, the timing of their administration is crucial. The authors have found that when done a week after the first symptoms, blood tests could only detect 30% of positive cases. The precision surged during the second week (70%) and peaked around the three-week mark (90%).
Conclusion
Urine toxicology and blood testing have a long history, and by now, they have been refined to meet the demands of the healthcare industry. The major breakthroughs in the history of blood testing included the discovery of blood types and the Rh factor as well as the invention of reliable tests for blood borne diseases. Urinalysis evolved to help look for early signs of disease, evaluate the efficiency of medical treatment, and detect the presence of substances. Despite the advent of laboratory testing, there are still some barriers to successful use of available technologies. As recent literature suggests, these barriers largely revolve around human communication and logistics. Blood testing and urine toxicology promote proactive healthcare as they play a role in preventing diseases. Yet, there are still some concerns regarding the accuracy of tests.
References
Castiglioni A. A history of medicine. Routledge; 2019.
Chernecky CC, Berger BJ. Laboratory Tests and Diagnostic Procedures-E-Book. Elsevier Health Sciences; 2012.
Blood tests [Internet]. Washington: National Heart, Lung, and Blood Institute; 2019.
Litchfield I, Bentham L, Hill A, McManus RJ, Lilford R, Greenfield S. Routine failures in the process for blood testing and the communication of results to patients in primary care in the UK: a qualitative exploration of patient and provider perspectives. BMJ quality & safety. 2015;24(11):681-90.
Faiella G, Parand A, Franklin BD, Chana P, Cesarelli M, Stanton NA, et al. Expanding healthcare failure mode and effect analysis: a composite proactive risk analysis approach. Reliability Engineering & System Safety. 2018;169:117-26.
Deeks JJ, Dinnes J, Takwoingi Y, Davenport C, Spijker R, Taylor-Phillips S, Adriano A, Beese S, Dretzke J, di Ruffano LF, Harris IM. Antibody tests for identification of current and past infection with SARS‐CoV‐2. Cochrane Database of Systematic Reviews. 2020(6).