What causes trace lysed blood in urine. How is trace lysed blood in urine diagnosed. What are the treatment options for trace lysed blood in urine. Is trace lysed blood in urine a serious condition. When should you see a doctor for trace lysed blood in urine.

Understanding Trace Lysed Blood in Urine

Trace lysed blood in urine is a medical finding that can be detected during routine urinalysis. It refers to a very small amount of blood in the urine where the red blood cells have broken open, or lysed. This condition falls under the broader category of microscopic hematuria, which means blood in the urine that is not visible to the naked eye.

Dr. Louis Kavoussi, chairman of urology for Northwell Health, explains, “With microscopic hematuria, the red blood cells are still intact. But with traced lysed blood in the urine, the cells are broken. So the conditions are a little different, but trace lysed blood in the urine starts off as microscopic hematuria before the cells break open.”

Is trace lysed blood in urine a cause for concern?

In most cases, trace lysed blood in urine is not a significant health concern. Dr. Kavoussi reassures, “Most of the time, it is not of any significance.” However, it’s essential to understand the potential causes and when further investigation might be necessary.

Causes of Trace Lysed Blood in Urine

There are several factors that can contribute to the presence of trace lysed blood in urine:

• Improper handling of the urine sample
• High urine alkalinity (often due to kidney disease or urinary tract infections)
• Extended storage of the urine sample
• Inflammation in the urinary tract
• Infections
• Injuries to the urinary system
• Strenuous exercise or physical trauma
• Kidney disease
• Exposure to certain chemicals

Dr. Vikas Desai, a urologist at Northwestern Medicine Delnor Hospital, adds that holding in urine or not urinating when you feel the need to can be risk factors for trace lysed blood in urine, as these behaviors can lead to urinary tract infections.

Diagnosing Trace Lysed Blood in Urine

Trace lysed blood in urine is typically detected through a routine urinalysis. This test uses a dipstick, which changes color in the presence of blood. Dr. Kavoussi explains, “Trace amounts of blood will cause the urine dipstick to become slightly discolored.”

What tests are used to diagnose trace lysed blood in urine?

In addition to the initial urinalysis, doctors may order several other tests to determine the underlying cause:

1. Blood tests
2. CT scan
3. Cystoscopy (a small camera inserted through the urethra to examine the bladder)
4. Kidney biopsy
5. Kidney ultrasound
6. Urine cytology (analysis of cells shed in urine)

Treatment Options for Trace Lysed Blood in Urine

In many cases, trace lysed blood in urine does not require specific treatment. Dr. Kavoussi states, “Often there is no specific treatment for trace lysed blood in the urine. The vast majority of the time it is not a life-threatening finding.”

However, if an underlying condition is identified, treatment will be tailored to address that specific issue. This may include:

• Antibiotics for urinary tract infections
• Lifestyle changes to reduce risk factors
• Treatment for kidney disease, if present
• Management of any identified injuries or traumas

When to See a Doctor

While trace lysed blood in urine is often not a cause for immediate concern, there are situations where medical attention is warranted.

When should you consult a healthcare professional about trace lysed blood in urine?

Consider seeing a doctor if:

• You experience persistent or recurring episodes of blood in your urine
• You have other urinary symptoms such as pain or burning during urination
• You have a history of kidney disease or urological issues
• You’ve been exposed to chemicals or have a history of smoking
• You have a family history of kidney or bladder disorders

Prevention and Risk Reduction

While not all cases of trace lysed blood in urine can be prevented, there are steps you can take to reduce your risk:

• Stay hydrated to maintain proper urinary function
• Urinate when you feel the need, rather than holding it in
• Avoid smoking and limit exposure to harmful chemicals
• Maintain a healthy diet and exercise routine
• Attend regular check-ups and follow your doctor’s recommendations for urinalysis screenings

Understanding Hematuria: The Broader Context

To fully grasp the significance of trace lysed blood in urine, it’s important to understand the broader context of hematuria, or blood in the urine. Hematuria can be classified into two main categories:

1. Gross hematuria: Blood that is visible in the urine to the naked eye
2. Microscopic hematuria: Blood that is only detectable under a microscope

Trace lysed blood falls under the microscopic hematuria category. According to a study published in the journal Deutsches Arzteblatt International, hematuria is quite common, affecting between 2% and 30% of the population.

How does trace lysed blood differ from other forms of hematuria?

The key difference lies in the state of the red blood cells. In typical microscopic hematuria, the red blood cells remain intact. However, in cases of trace lysed blood, these cells have ruptured. Dr. R. Mark Ellerkmann, an assistant professor at Johns Hopkins School of Medicine, explains, “Under the microscope, it looks as if the red blood cells have ruptured.”

The Role of Urine pH in Trace Lysed Blood

The pH level of urine can play a significant role in the presence of trace lysed blood. Urine that is highly alkaline (having a high pH) can cause red blood cells to break down more easily.

What factors can affect urine pH?

Several factors can influence the pH of urine:

• Diet: Certain foods can make urine more alkaline or acidic
• Medications: Some drugs can alter urine pH
• Kidney function: Impaired kidney function can affect the body’s ability to regulate urine pH
• Urinary tract infections: These can often lead to more alkaline urine

Understanding these factors can help healthcare providers determine the underlying cause of trace lysed blood in urine and develop appropriate treatment strategies.

Long-term Outlook and Monitoring

For most individuals, the presence of trace lysed blood in urine is not a cause for long-term concern. However, it’s important to follow up with your healthcare provider and adhere to any recommended monitoring or follow-up tests.

How often should you have your urine checked after a finding of trace lysed blood?

The frequency of follow-up urinalysis tests will depend on several factors:

• Your overall health status
• The presence of any underlying conditions
• Your risk factors for urological issues
• Your doctor’s assessment of your individual case

Your healthcare provider will develop a personalized monitoring plan based on these factors. This may involve regular urinalysis tests, imaging studies, or other diagnostic procedures to ensure your urinary health remains stable.

The Impact of Lifestyle on Urinary Health

While not all cases of trace lysed blood in urine are preventable, certain lifestyle factors can significantly impact your overall urinary health and potentially reduce the risk of developing this condition.

How can lifestyle changes improve urinary health?

Consider implementing the following lifestyle modifications:

• Maintain proper hydration: Drinking adequate water helps flush out the urinary system
• Practice good urinary habits: Urinate when you feel the need, and avoid holding it for extended periods
• Exercise regularly: Physical activity can improve overall health, including urinary function
• Manage stress: High stress levels can impact various bodily functions, including urinary health
• Quit smoking: Smoking is a risk factor for various urological issues
• Limit alcohol and caffeine intake: These substances can irritate the bladder and affect urinary function

By adopting these healthy habits, you can contribute to better urinary health and potentially reduce the risk of developing trace lysed blood in urine or other urological issues.

What Is Trace Lysed Blood in Urine?

GettyImages/xavierarnau

Urine tests are routine–most everyone has peed in a cup for their doctor at one time or another. But what happens when the tests come back and you see “trace lysed blood in urine” on the report? That blood part may be alarming to you.

First things first: You probably have nothing to worry about from a report of trace lysed blood in urine. “Most of the time, it is not of any significance,” says Louis Kavoussi, M.D., chairman of urology for Northwell Health and professor of urology at the Zucker School of Medicine at Hofstra/Northwell in Uniondale, NY.

So what does it mean when you have trace lysed blood in your urine? Here’s what you need to know about what it is, what may be causing it, and what treatment you might need.

Blood in Urine, Explained

If blood is found in your urine, you have hematuria, which could have many causes ranging from an infection to trauma to bladder or kidney disease. Hematuria is labeled either “gross,” when you can see the blood in your urine, or “microscopic,” meaning it is visible only under a microscope. Either way, blood in urine is very common. A study in the journal Deutsches Arzteblatt International estimates that somewhere between 2% and 30% of the population has it.

What Is Trace Lysed Blood in Urine?

“Trace” means a very small amount of blood, while “lysed” means that the walls of the red blood cells in the urine have broken open and are no longer intact, explains Dr. Kavoussi.

“Under the microscope, it looks as if the red blood cells have ruptured,” explains R. Mark Ellerkmann, M.D., an assistant professor at Johns Hopkins School of Medicine in the department of gynecology and obstetrics and director of the Center for Urogynecology at the Weinberg Center for Women’s Health and Medicine at Mercy Medical Center in Baltimore, MD.

Trace lysed blood in the urine is a subcategory microscopic hematuria, Dr. Kavoussi says. “With microscopic hematuria, the red blood cells are still intact,” he explains. “But with traced lysed blood in the urine, the cells are broken. So the conditions are a little different,” he says, but adds that trace lysed blood in the urine starts off as microscopic hematuria before the cells break open.

What Causes Trace Lysed Blood in Urine?

While red blood cells are designed to break down naturally every 110 to 120 days on average, if they are breaking down in your urine, there’s usually another cause at work.

Red blood cells in the urine can break open if the urine sample is handled improperly, if the urine is very alkaline—meaning it has a high pH, usually caused by kidney disease or a urinary tract infection (UTI)—or if the urine sample is stored too long, Dr. Ellerkmann says. In some cases, it may occur if there is inflammation, an infection, or an injury, he says.

“The finding needs to be looked at, along with the results of other blood tests, symptoms, and any history of exposure to cigarette smoking, chemical exposure, and family history,” Dr. Kavoussi says. “A history of cigarette smoking puts you at risk for kidney disease,” which can cause blood in the urine, he adds.

Holding in urine or not urinating when you feel the need to are risk factors for trace lysed blood in the urine, says Vikas Desai, MD, a urologist at Northwestern Medicine Delnor Hospital in Geneva, IL, because it’s a risk factor of a urinary tract infection, which can cause microscopic hematuria. “Trauma or injuries to your muscle during a car crash also could be responsible, as could strenuous exercise and training for a marathon,” he says.

Diagnosing Trace Lysed Blood in Urine

There are no symptoms of trace lysed blood in urine, says Dr. Kavoussi. In fact, since you can’t even see it with the naked eye, you’ll need a urine test, or urinalysis, to know you have it.

If your doctor has reason to be concerned about blood in your urine or is trying to diagnose an infection, you’ll be asked to provide a urine sample for testing. The test uses a dipstick, which can quickly detect tiny amounts of blood in your urine. The dipstick is a chemical strip that changes color when certain substances are present or if their levels are high. Trace amounts of blood will cause the urine dip stick to become slightly discolored, says Dr. Kavoussi.

Other tests that may be helpful in diagnosing the cause of lysed blood in urine can include:

• Blood tests

• CT scan

• Cytoscopy (a small camera that is inserted through the urethra—using numbing gel—to check the bladder)

• Kidney biopsy

• Kidney ultrasound

• Urine cytology (analysis of cells lining the bladder and kidneys that are shed in urine)

Treatment for Trace Lysed Blood in the Urine

“Often there is no specific treatment for trace lysed blood in the urine,” Dr. Kavoussi says. “The vast majority of the time it is not a life-threatening finding. Usually, the doctor will follow you over time and other tests may be indicated if the amount of blood increases.”

While there is no specific treatment for trace lysed blood itself, Dr. Kavoussi says, whatever is causing the trace lysed blood may need to be addressed. The most common, according to the American Academy of Family Physicians (AAFP), include:

• Benign prostatic hyperplasia (enlarged prostate)

• Bladder stones

• Kidney disease

• Urinary tract infection

No cause can be found between 43 and 68% of the time, according to the AAFP.

Yes, blood in your urine can be worrisome. But if you can’t see it, and only know you have trace lysed blood in urine because a urinalysis told you so, you can breathe a little easier. The presence of trace lysed blood in urine is common and not especially worrisome, Dr. Kavoussi says. “It is an isolated finding and does not mean a whole lot,” he says. “In the vast majority of cases, it means absolutely nothing.”

Notes: This article was originally published January 30, 2012 and most recently updated May 22, 2023.

Definition of Hematuria: National Institute of Diabetes and Digestive and Kidney Disorders. (2022.) “Hematuria (Blood in the Urine).” https://www.niddk.nih.gov/health-information/urologic-diseases/hematuria-blood-urine

Incidence of Blood in Urine: Deutsches Arzteblatt International. (2018.) “The Investigation of Hematuria.” https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6365675/

Causes of Hematuria: Cleveland Clinic. (2022.) “Hematuria.” https://my.clevelandclinic.org/health/diseases/15234-hematuria

Red Blood Cell Lifespan: MedLinePlus. (2022.) “Hemolysis.” https://medlineplus.gov/ency/article/002372.htm

Hemolysis Definition: Journal of Medical Biochemistry. (2018.) “Effect of Blood Cell Subtypes Lysis on Routine Biochemical Tests.” https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6294101

Urine pH: MedLinePlus. (2021.) “Urine pH test.” https://medlineplus.gov/ency/article/003583.htm

Diagnosis: UpToDate. (2022.) “Patient education: Blood in the urine (hematuria) in adults (Beyond the Basics). ” https://www.uptodate.com/contents/blood-in-the-urine-hematuria-in-adults-beyond-the-basics

Dipstick: Urology Care Foundation.” (2020.) “How blood in the urine is tested and treated.” https://www.urologyhealth.org/healthy-living/care-blog/2020/how-blood-in-the-urine-is-tested-and-treated

Kidney Disease Symptoms: World Journal of Nephrology. (2015.) “Pathogenesis of glomerular haematuria.” https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4419128/

Treatments for Blood in the Urine: American Academy of Family Physicians. (2022.) “Microscopic Hematuria.” https://familydoctor.org/condition/microscopic-hematuria/

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Is Blood in your Urine a Reason to be Concerned?

If you notice blood in your urine, don’t ignore it. There are many possible causes of this condition, known as hematuria. While some are simply treated and not dangerous, others may need immediate medical attention.

Not all hematuria can be seen with the human eye. In fact, the most common type of hematuria-called microscopic hematuria-can only been seen by a health care expert under a microscope. In many cases, microscopic hematuria is spotted when a person has a urine test during a health exam.

When a person can see the blood in his or her urine, the condition is called gross hematuria. People with gross hematuria have urine that is pink, red or brown.

“There’s a common misconception that if you see blood in your urine once and then it goes away that you’re in the clear,” says Angela B. Smith, MD, Assistant Professor of Urology at the University of North Carolina School of Medicine in Chapel Hill. “But it’s important to seek care the very first time you see blood in the urine, so your doctor can confirm that it’s there and refer you to a urologist for an evaluation. “

In most cases, people with either type of hematuria do not have pain or any other signs or symptoms.

What Causes Hematuria?

Common Causes of Hematuria: 

• Urinary tract infection
• Enlarged prostate
• Kidney stones
• Vigorous exercise such as long-distance running
• Certain drugs, such as blood thinners, aspirin and other pain relievers, and antibiotics

More serious causes are swelling of the kidney, urethra, bladder or prostate, or cancer of the kidney or bladder. Only a small percentage of people with microscopic hematuria have cancer. A history of smoking raises the risk of bladder or kidney cancer.

Risk Factors for Hematuria: 

• A family history of kidney disease
• Chronic urinary tract infection 
• Smoking
• Exposure to chemicals in the workplace
• Treatment with radiation for pelvic cancer

“In many cases, kidney cancer and bladder cancer do not cause physical symptoms, so the tumor may continue to grow without a person being aware of it,” says Michael J. Kennelly, MD, Professor in the Department of Surgery, Division of Urology at the Carolinas Medical Center – Charlotte in North Carolina. “By the time the tumor does cause symptoms, it may not be curable. That’s why it is so important to seek medical attention if you see blood in your urine. It could be a warning sign for a potentially life-threatening illness. Fortunately, the majority of the time, blood in the urine is not a sign of a serious illness.”

Diagnosing the Cause

If your doctor thinks you may have hematuria, you will have a repeat urine test to make sure the first test was right. Your doctor will ask you about your health history, including infections, kidney stones, smoking, menstruation and recent injuries. He or she will also ask about medications you are taking.

Your doctor will perform a physical exam to check for pain or tenderness in the bladder or kidney area. Men may be given a digital rectal exam to look for prostate problems. Women may have a pelvic exam to look for the source of red blood cells in the urine.

Other Tests May Include:

Cystoscopy. This is a procedure a urologist performs to see inside the bladder and urethra (the tube that allows urine to pass out of the body). The doctor uses a thin tube with a camera and light on the end–called a cystoscope–to look for cancer cells or other problems.
Kidney imaging tests. The doctor may order an imaging test such as ultrasound, CT scan or MRI to look for a tumor, a kidney or bladder stone, an enlarged prostate or other problem.

Your doctor may order one more urine test to look for signs of infection, kidney disease and cancer. You may have a blood test to check for high levels of the protein creatinine, a sign of kidney disease.

In many cases, the doctor is not able to find out why there is blood in the urine, Dr. Smith notes. He or she may decide to retest your urine in a year. If blood is found, you may undergo more tests. Or you may be retested several years later.

Treatment

Hematuria is managed by treating its underlying cause. For example, if the condition is caused by a urinary tract infection, it is treated with antibiotics. Treatment for kidney stones can include waiting for the stone to pass by itself, medication or surgery.

If you are found to have kidney or bladder cancer, your doctor may refer you to an oncologist or urologic surgeon. If the tumor is found early, the cancer often can be cured. There are a number of options for kidney and bladder cancer treatment, including surgery, chemotherapy and radiation.

If the doctor rules out any medical problem causing hematuria, you will not need treatment.

“If you find blood in your urine, or your doctor tells you that you have microscopic hematuria, don’t panic,” Dr. Kennelly says. “The good news is that with proper evaluation, your doctor can find out the cause and if needed, make sure you get the correct treatment right away.”

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Forensic characterization of traces of blood at the scene of the incident

During the period of military service, the possibility of conflict situations between servicemen, the commission of self-mutilation with infliction of injuries accompanied by external bleeding is not ruled out. Material evidence of biological origin is also discovered and seized during the examination of victims and persons suspected of a crime, searches and other investigative actions and are subject to a forensic medical examination.

One of the main places among the material evidence of crimes against human life and health is occupied by traces of blood. Traces of blood in forensic medicine and criminology are understood as the presence of any amount of blood in the environment, outside the human or animal body.

The study of blood traces aims to obtain mainly diagnostic information about the location of a person (the source of bleeding), his movements and other actions of expert significance.

Blood traces can be divided into two large groups: contact and non-contact. There are also static and dynamic, local and peripheral, primary and secondary traces of blood.

In the work of forensic medical experts, the classification of blood traces has become widespread, dividing them into:

1. Elementary traces are single traces that provide information about the physical factors that formed them and which depend on the properties of the trace-receiving surface.
2. Complex traces – a set of traces that provides information about the dynamics and conditions of their formation.

Morphological features of elementary and complex traces are largely determined by the mechanisms of their formation.

Puddles (clumps) are formed as a result of the outflow of blood spreading over a non-absorbent surface that does not have a steep slope. Particularly large puddles are found at the site of profusely bleeding injuries.

Impregnations are formed on porous surfaces, forming, unlike puddles, areas of saturation of the absorbent material with liquid blood. On multilayer textile objects, by the location of the stains and the degree of spread to different layers, it is possible to restore the initial relative position of the layers of the victim’s clothing [1].

Leaks are formed when liquid blood enters the gap between two closely spaced surfaces, where it is drawn under the influence of surface tension. If, at the time of the blood flow, the objects were in close contact, and after it had dried, they were separated, the shape of the blood flow on each of them would be the same, which would make it possible to prove their previous contact with each other.

Streaks are traces formed in the form of strips when blood drains under the influence of gravity along steep or inclined surfaces. In the lower part of the drip, a club-shaped thickening is noted. On smooth surfaces, streaks are usually straight, on uneven surfaces – tortuous. In the event of a change in body position with continued bleeding, the streaks will change their direction.

Drops. A drop is the minimum amount of liquid for given conditions, which takes a rounded shape due to the adhesion of its particles. When drops fall from stationary objects onto a horizontal smooth surface, the shape and size of the spot depend on the height of the fall. When drops fall from an object moving at low speed (a walking person), the shape of the blood spot becomes pear-shaped with thinning in the direction of movement. In the case of droplets falling on an inclined surface, the shape and character of the spot change somewhat: the spot lengthens in the direction of the slope, and the lower part of the trace is thicker. Thus, these traces help to determine the direction of movement of the wounded, to identify the pace of movement, the places of stops.

Splashes are traces of blood resulting from the collision of flying droplets with fixed obstacles. The shape of the splashes depends on the angle of their incidence on the barrier; when they come into contact with the surface at an acute angle, the splash marks have an elongated pear-shaped shape or an exclamation mark shape. When struck with a blunt object on a bloody surface at a right angle, the splashes spread in all directions, at an acute angle, mainly in the direction opposite to the blow.

Blood smears are formed as a result of sliding contact of a bloody part of the body or an object stained with blood, with any surface. A special kind of smears are traces of dragging, formed during the sliding movement of a massive bloody object.

Blood impressions are formed by static contact of a blood-stained object with a flat surface. These footprints may show signs of a trace-forming object and be used for identification purposes.

In the resolution on the appointment of a forensic medical examination, the main issue is to establish the mechanism for the formation of traces of blood, which is the subject of a medical forensic examination.

Detection and removal of traces of blood for their subsequent expert examination is one of the tasks of the investigator conducting the inspection of the scene. Inspection is carried out with the naked eye or with a magnifying glass in sufficiently intense natural or artificial light.

When examining the instruments of injury and other objects, certain rules must be observed: work with rubber gloves, touch only areas free from traces, do not disassemble and separate parts of the object at the scene of the incident.

In rooms, carefully inspect floor cracks, under skirting boards, ventilation grilles, on furniture legs, on door handles, windows, cabinets, tables. Particular attention should be paid to places where the offender could wash clothes and instruments of injury (water taps, sinks, basins, buckets, drains, seams between tiles. )

Garments should be inspected from the front and from the wrong side, where washed spots can be found. Particular attention is paid to hidden places where traces of blood are more difficult to destroy or notice: seams, pockets, material behind buttons, etc.[2]

It is necessary to carefully examine the hands of a suspect in a crime, to remove the subungual contents. In sexual crimes, traces of blood can be found on the genitals and on the thighs.

In doubtful cases, as well as in cases of deliberate destruction of traces of blood by the criminal, their detection will be facilitated by preliminary tests:

1. UV inspection;
2. Sample with 3% hydrogen peroxide solution;
3. Sample with “Voskoboynikov’s reagent”;
4. Test with reactive paper “Gemotsvet – 1”;
5. HemoFan assay;
6. Luminol test.

Fixation of traces of blood is carried out by photographing, a detailed description in the inspection protocol, measurement and drawing on the plan.

First, an overview large-scale photograph of the general view of the location of blood traces at the scene of the incident is made, then nodal, with their location on separate objects, and detailed, fixing individual traces or their groups.

In all cases, only items with dry traces should be removed and packed. Traces of blood, if possible, are taken together with the trace-bearing object or with a part of it. When it is not possible to remove even a part of the object, they resort to scraping or flushing. A part of the trace-bearing object is also sent for a control study. Liquid blood is collected on clean gauze.

The seized and packaged traces of blood are sent for a forensic medical examination.

To solve identification problems, a forensic medical (biological) examination is carried out, which solves the following problems[3]:

1. Establishing the presence of blood is based on the detection of the coloring substance of blood – hemoglobin – and its derivatives.

2. Determining the type of blood is dictated by the circumstances of the incident, when in the process of investigation there are versions about the origin of blood on objects not only from humans, but also from animals.

3. Determination of blood grouping is possible on objects, in dismembered parts of corpses, in liquid blood taken from victims or suspects as samples. In forensic practice, to solve identification problems, the blood group is determined within the erythrocyte system, as well as in systems R.Lewis , MNSs . Rhesus and others.

Determining the grouping of blood makes it possible to exclude its belonging to a certain person (victim or suspect) or indicate that such an exception cannot be made.

Recently, biological science has developed and successfully introduced into everyday practice the method of genotyposcopic identification of a person, which is based on the analysis of deoxyribonucleic acid (DNA) found in the nuclei of any cells of the human body.

4. Determination of pregnancy by detecting chorionic gonadotropin in the blood.

5. Determining whether blood belongs to an infant or an adult.

6. The definition of regional bleeding is based on the detection of cells or impurities in the contents of those organs from which the blood flowed.

7. Determining the age of blood stain formation. It is determined by the change in blood hemoglobin.

8. Establishment of the amount of spilled blood by stains.

9. Determining the origin of blood from a living person or from a corpse.

The solution of the last three problems has not found wide application in practice[4].

Thus, traces of blood occupy one of the main places among the material evidence of committed crimes against the life and health of a person. The forensic significance of traces of blood is based on the study of its biological properties and on the analysis of the totality of traces of blood at the scene, both in terms of their appearance and localization.

A comprehensive assessment of traces at the scene on the clothes and bodies of victims and suspects, on the instruments of injury, in some cases, allows you to conduct a situational analysis of the incident, to establish not only the mechanism for the formation of individual traces of blood, but also to obtain information about the conditions for their occurrence, the location of the person at the moment of causing damage, its subsequent movements and other actions, i.e. restore the dynamics of the incident.

[1] V.N. Kryukova Forensic medicine. – Norma, M., 2008. – S. 57.

[2] I.A. Gedygushev Forensic medical examination in the reconstruction of the circumstances and conditions of causing damage (methodology and practice). – M., 1999. – S. 78-83.

[3] Nazarov G.N., Pashinyan G.A. Medico-forensic investigation of traces of blood: A practical guide. Nizhny Novgorod: Publishing house of NGMA. 2003. – S. 102-111.

[4] Inspection of the scene. Handbook for doctors and lawyers. – Ed. A.A. Matyshev and Professor Yu.A. Molina. – NPO “Professional” St. Petersburg, 2011. – S. 65-78.

More in this category:
«Problems of qualifying crimes related to military evasion by desertion

«There was blood on the soles» Killers make fatal mistakes at the crime scene. What gives them away?: Books: Kultura: Lenta.ru

Poirot could easily tell which weapon the bullet had been fired from, and Miss Marple was a master at blood spatter analysis. Also, Agatha Christie loved to “kill” the heroes of her books with various poisons, which is explained by her work in a pharmacy during both world wars. In The Recipe for Murder, forensic scientist Carla Valentine talks about how Agatha Christie managed through the cases that were revealed in her books to contribute to the development of a new science for everyone, later called “forensic science”. With the permission of the Bombora publishing house, Lenta. ru publishes a fragment of the text.

When archaeologists unearth ancient clay pot shards, they are registered, cleaned and reconstructed. The pot is either photographed for publication in magazines or put on public display in a museum. Depending on the state of preservation of the potsherds, the cracks in the reconstructed pot may be almost imperceptible: the skillful and careful hands of the archaeologist do their best to repair the damage.

This is how the broken heart of Agatha Christie was restored by archaeologist Max Mallowan. After the most difficult year of her life, when she experienced the betrayal of her husband, the death of her beloved mother and a period of psychological and emotional distress (in other words, a nervous breakdown), Agatha Christie found herself on the threshold of her 40th birthday alone, and she really needed a vacation. In modern terms, she wanted to find herself.

Although Christie had already bought a ticket to the West Indies for this purpose, she was fascinated by stories about the Middle East she once heard at a dinner party, and so she decided to go to Baghdad on the Orient Express. The journey had a huge impact on the later life of the writer and honed her talents, just as a craftsman shapes pieces of flint, turning it into pointed tools and arrowheads.

During a visit to Mesopotamia, Christie visited the excavation site of the famous archaeologist Leonard Woolley, and there she met his assistant, Max, her future husband. Agatha and Max returned to this most mysterious corner of the planet until the end of their lives.

While working on the books, Christy managed to help Max by cleaning, photographing and sketching the finds. She described this process in some of her writings, including Murder in Mesopotamia and Appointment with Death.

Agatha helped excavate famous artefacts, and, interestingly, National Geographic magazine compared this work to conducting an investigation: “Max Mallowan, Christie’s second husband, was the” senior investigator “and the “detectives” were not the police, but archaeologists”

Archeology is often compared to detective work, so it is not surprising that Agatha liked it (there is even a separate discipline called “forensic archeology”). Tool marks, footprints, and cuts play no less important role in archeology than in forensics, but have a slightly different meaning.

For example, in archeology, a “slice” is a kind of slice, consisting of various cultural layers, each of which reflects a certain historical period. When something was dug up or buried in the past, it was within the specific time frame of archaeology.

A grave dug many decades or centuries ago will be covered with several layers of earth, and archaeologists will be able to determine from them when it was originally dug. They will find “evidence”, such as shards of crockery and possibly coins with the year on them. The layers and the artifacts they contain make it possible to recreate a complete picture – the same as we see at the end of a detective novel or at the end of a crime scene.

Murder in Mesopotamia series

Frame: Agatha Christie’s Poirot series

Like artifacts found during excavations that need to be evaluated according to various criteria (what they are, what cultural layers they were in, what other objects or organic traces were nearby, etc. ), evidence also requires complex research.

For example, when a bloody footprint of a shoe is found, an analysis of blood splashes and sole prints is required, and when an ink fingerprint is found, fingerprinting and forensic examination of the document are required. Christie often combines different types of evidence. For example, in the novel Cards on the Table, Colonel Race speaks of “a soiled glove, fingerprints on a dentifrice glass, a piece of burnt paper.”

This chapter brings together various types of evidence that are closely related to each other, although at first glance it may not seem so. People whose work is related to forensics may be experts in not one, but two or three areas at once.

Many forensic scientists work in tandem: blood splatter experts team up with serologists (experts in bodily fluids), and medical examiners team up with toxicologists. Archaeologists have discovered many places where prehistoric footprints were visible – traces of ancient people that have been preserved for millions of years. The same tools and “evidence” are used to reconstruct the past, whether it’s a burial place in ancient Greece or the scene of a crime committed just yesterday.

In a forensic context, a trace occurs when one object comes into close enough contact with another object to leave an imprint or indentation on it.

Fingerprinting, forensic ballistics, and even document forensics deal with fingerprints: fingerprints on putty, screw marks on a fired bullet, embossed text on a notepad sheet, etc.

However, in this chapter we will focus on the types of evidence that as footprints, as well as traces of tools, tires and dragging. Then we’ll talk about the different types of edged weapons and the bodily harm they cause. We will consider them as a separate type of physical evidence, since they go hand in hand: often during an autopsy, the medical examiner determines which weapon caused a particular wound. He does this by examining the mark he left on the soft tissues or bones of the victim.

Agatha Christie photographs an Assyrian ivory figure in Nimrud, Iraq. There, her husband, Sir Max Edgar Lucien Mullovan, was excavating the site of the ancient Assyrian military capital. Fingerprints, for example, are considered non-damaging because they are simply a unique and specific pattern. As the title of this chapter suggests, damage marks occur when an object receives or inflicts an injury, leaving a specific mark. Such marks are left by shoes and tools, which become even more valuable evidence when they have distinctive features as a result of wear and use (like the typewriters discussed earlier).

Forensics textbooks say, “Millions of rubber soles are practically the same at the time of production and sale, but after just a few days of wear they acquire individual characteristics.” Simply put, the more worn out the outsole of a shoe, the more unique its footprint becomes.

There is a difference between group characteristics, which combine evidence with similar features (knives or hammers, for example), and individual characteristics, which link evidence to a specific person or object. Sneaker sole marks found at a crime scene can be run through a database to determine the shoe brand.

Let’s assume that the sneakers are made by Reebok – this is the group to which they belong. With further research, it is possible to identify individual identification signs – traces of wear on the soles of sneakers, reflecting the unique way of wearing shoes that is characteristic of a particular person. Uniqueness is determined by the characteristics of the gait, the distribution of weight during movement, the surface on which the person moves, how often this pair of shoes was used, and so on.

The Murder of Roger Ackroyd episode

Frame: Agatha Christie’s Poirot episode

The police might have a suspect (let’s call him Bill) and if experts examine other pairs of his shoes and find that the wear marks on them match those left at the crime scene, there’s a good chance the Reeboks are Bill’s. If the cops manage to find the right pair from Bill, it will be a good deal, and they will know that they are on the right track. If the shoes are not found, the investigator can check the suspect’s banking history and see if he ever bought sneakers from such a company and when he did it: before
a crime was committed, or after.

Agatha Christie was very good at traceology, and this becomes evident in The Murder of Roger Ackroyd.

When the shrewd Inspector Raglan begins his investigation, he takes the shoes belonging to the suspect: “Here are his shoes. They have ribbed rubber soles. He has two pairs of these boots. I grabbed them to compare with the prints on the windowsill.” After that, the inspector compared them with the footprints on the windowsill:

“The same ones,” he said confidently. – That is, this is not that pair – he left in that one. But this pair is completely identical to that one, only the old one – look how worn out the soles are. Christy, without realizing it herself, speaks of group and individual identification features! Group signs are the same brand or type of shoe (“this pair is exactly the same as that one”), and individual signs are soles worn in a certain way.

Footprints are useful because they help to understand whether one person was present at the crime scene or several. Thus, they are able to confirm or refute testimony and alibis.

Footprints also show where a person came from and where they went. A typical example is the footprints on the flower bed under the window and the earth from it in the room (in this case, it is clear where the person came from). In the novel The Mystery of Chimneys Castle, which is more of a thriller than a detective story, Agatha still does not leave the reader without a corpse.

While investigating the murder of Count Stanislaus at the wealthy Chimneys estate, detectives find dirty footprints outside the house, near the open window where the body lay. They came to the conclusion that the perpetrator left traces when he climbed into the house through an open window and then climbed out into the street. The same scenario is repeated in several stories: Agatha had a clear understanding of trace evidence and its role in the reconstruction of the crime.

The Chimneys Castle series

Frame: Agatha Christie’s Miss Marple series

Most importantly, in the case of several crimes, the same traces can indicate a connection between them. The same footprints in different places allow not only to connect the crimes with a person, but also to draw a parallel between various pieces of evidence that are useless on their own, but together help solve the case.

For example, at one crime scene the police will find traces and blond hair, at another – traces and blood splatters, the analysis of which will show that the offender was about 180 centimeters tall, and at the third – traces and fibers of a Ford rug. Separately, these pieces of the puzzle may not be very informative, but when they are put together, the police will understand that they need to look for a blond man who is about 180 centimeters tall, who drives a Ford.

Evidence like this can narrow down the list of suspects considerably, or at least point to where to investigate. How do specialists, having collected material evidence, examine it? First, let’s look at footprints. Trace examination depends on how they look.

There are three main types, like fingerprints. Clear footprints are visible to the naked eye, as are fingerprints. They usually remain when a person walks on paint or dirt and pulls them away. If, after a particularly brutal murder, bloody rather than muddy footprints lead to the back of the house and out the door, this means that the person who was present at the crime scene left that way.

In the story “The Boar of Erymanthus”, Poirot describes it this way: “Footprints… I think there was blood on the soles, and they come from an uninhabited wing of the hotel.” It was enough just to photograph them at a right angle to avoid distortion. It is very important to place a ruler next to the footprint in order to accurately determine its length and determine the size of the person’s foot. To fix faintly visible traces so that they are more clearly visible in the photograph, obliquely directed light is used. In the same way, experts use special lighting to distinguish embossed text on paper.

Invisible footprints cannot be detected without special equipment. These are the marks left by seemingly clean shoes on a smooth surface. On a “clean” sole, a mixture of oils and dusty substances may remain, which will be transferred when walking, for example, on glass, linoleum or paper. Invisible marks can also be the result of static electricity. Take a look at a balloon that has been flying around the room for several days: there will be hair, dust and small debris on its surface, attracted by static electricity.

Finding invisible prints is tricky, but experts with years of experience and many crime scenes know how to do it. Such traces can be made visible using fingerprint powder, and then removed with film or tape. Today it is common to use silicone pastes (compounds) or a special electrostatic device to transfer the print to the film, but in Christie’s time this was not possible. Now you understand what fingerprints and footprints have in common and why some forensic experts are experts in several fields at once.

Three-dimensional traces are the first thing that comes to mind when thinking about detective novels.

These are three-dimensional prints left on some plastic surface (mud, sand, snow, etc.) as a result of pressure. They need to be photographed (especially if they are in the snow), after setting the light in such a way that the camera conveys all the details as accurately as possible. Volumetric traces on a dispersed basis (dust, flour, cement, and so on) are first sprayed with shellac or hairspray to stabilize the material and make the outlines more contrasting.

After that, the imprint is surrounded by a wooden frame and the resulting rectangle is filled with gypsum or silicone paste, which penetrates into all the grooves of the imprint. The solution solidifies, and the result is a three-dimensional cast of the trace. Plaster has indeed been used for this purpose in the past, and as early as 1924 Christie mentions this method of removing footprints in the storybook The Accomplices, which tells of the adventures of Mr. Tommy and Mrs. Tuppence Birsford, a husband and wife who run a private detective agency.

Trial of Innocence episode

Frame: Agatha Christie’s Miss Marple series

In “The Case of the Pink Pearl,” Tuppence asks Tommy, “I hope you’ll be making plaster casts of the footprints?” A forensic textbook published in the 1930s describes interesting alternative methods that can be applied in the absence of a cast. In emergencies, pork fat, porridge, or a mixture of flour and water was used instead. Salt added to gypsum accelerated the drying process, while sugar, on the contrary, slowed it down.

Who would have thought there were so many items in the kitchen cupboard that could be used during a scene inspection? Tire tracks are a lot like sole prints: they can be voluminous if left on mud or grass; obvious if the vehicle drove over blood, tar or paint; and even invisible, since they can be made up of oils used in the manufacture of tires. Vehicle tracks are removed in the same way as shoe prints.

Surprisingly, cars did not occupy an important place in Christie’s works, although they became the main mode of transport during the life of the writer, and she was very fond of her “Morris Cowley”

For this reason, I will not pay much attention to tire tracks.

The branch of forensic technology is transport traceology, which deals with wheel tracks, younger than that which analyzes sole prints. It should be noted that once Agatha still uses tire tracks as evidence – in the story “Gold Bars” (1928). Inspector Badgworth, one of the main characters, is investigating a possible location for the stolen gold and notices clear tire tracks, the individual identification of which could be very important.

It indicates a defect in one of the tires:

“One of the treads is damaged and leaves a very characteristic print.” On a hunch, Budgworth examines the suspect’s truck, taking with him Miss Marple’s nephew, Raymond West, who is also the narrator (he appears or is at least mentioned in many of the Miss Marple novels and stories).