Connect with us

Medical Devices / Diagnostics

VDRL test: What to know



The laboratory procedure for venereal disease research (VDRL) is a blood test that can recognize infections with the syphilis. Syphilis is one of Sexually Transmitted Infections (STIs) most common.

In 2018, 115,045 new cases of syphilis were identified in the Centers for Disease Control and Prevention (CDC).

Untreated syphilis, including the brain, spinal cord and heart, can damage vital organs.

Doctors can diagnose syphilis and other early stage STIs with the help of screening and testing procedures.

This article looks at the VDRL test which is one form of screening test for syphilis.

What is it?

A doctor may order a VDRL test to diagnose syphilis.
A doctor may order a VDRL test to diagnose syphilis.

The VDRL test is one of three Nontreponemal tests for syphilis detection. Nontreponemal tests are not syphilis objective, and may show false-positive results.

Doctors can not single-handedly diagnose syphilis infections based on positive VDRL tests alone. We need a treponemal test, which is specific to syphilis, to confirm the infection.

A doctor may do a VDRL test on either the blood or the spinal cerebral fluid (CSF).

Usually, a CSF VDRL test happens when a doctor believes the syphilis is at a more advanced stage when it can affect the brain and central nervous system. That is known as neurosyphilis.

A doctor can extract CSF for this examination through a procedure called a lumbar puncture which is also known as a spinal tap.

How does it work?

The bacterium Treponema pallidum (T. pallidum) causes infections with the syphilis.

If T. Pallidum enters the body, and the immune system produces antibodies that are proteins that destroy bacteria that invade it.

The VDRL test fails to respond to the T. Bacterium pallidum. Rather, the test tests the amount of antibodies in the blood, or CSF.

Healthcare providers collect a sample of blood or spinal fluid and send it out to a laboratory where it is tested for antibodies by a technician.

A blood test with VDLR involves adding to the blood sample a colorless alcoholic solution consisting of cardiolipin, lecithin, and cholesterol.

A CSF test involves the addition of a lipid mixture, called reagin. It suggests a positive reaction if clumping happens, and hence the presence of syphilis.


Health care providers conduct VDRL tests in most cases by taking blood samples. They can perform the test though using a CSF sample.

Blood draw

A blood test requires the injection of a hollow needle into a vein in the elbow or back of the hand by a health care provider.

The blood flows into an airtight collection tube that is attached to the other end.

Before inserting the needle, a healthcare provider may tie a rubber band or tourniquet above the injection site to make it easier to locate the veins.

CSF collection

CSF samples are obtained by health care providers through a process known as a lumbar puncture or spinal tap.

A person will lie on their side during the procedure and pull their knees towards their chest.

The healthcare provider will disinfect the injection site with a local anesthetic and become numb.

They will then insert a spinal needle into the lower spine which is used to extract a small amount of CSF.

What do the results mean?

The laboratory will forward the findings to the physician who ordered the examination.

The physician will clarify the test results of a person either at a follow-up appointment or over the phone.

The trial can take 3–5 days.

Negative results

Negative test results typically mean that the blood does not contain any antibodies to syphilis.


A negative result of a VDRL blood test suggests that there is no evidence of an infection.

People who get a negative result usually don’t need additional testing.

People with a high risk of syphilis, however, may want to consider getting routine screening tests about every three months.


According to the New York City Department of Health and Mental Hygiene Bureau of Sexually Transmitted Infections, a negative CSF result does not rule out a diagnosis of neurosyphilis.

Positive results

A positive result means that the VDRL test detected the presence of the syphilis antibodies.


The blood test with VDRL isn’t always successful. Infections like HIV or pneumonia and other autoimmune disorders can cause a false-positive outcome.

If the result is positive, another test, such as the fluorescent treponemal absorption assay, will be carried out by a doctor. The test will decide if the infection is syphilis.


A doctor will typically recommend a CSF VDRL test when they believe a individual may have late syphilis stages.

Usually, if a person is given a positive result, a doctor may conduct a treponemal test that detects the antibodies to the T Pallidum proteins. If this is positive it means that the central nervous system has been compromised with syphilis.

However, sometimes the doctors test in reverse for syphilis. They will start by testing a person with a tréponemal test specific to syphilis. If this proves positive, they will carry out a nontreponemal test, like a VDRL


The VDRL test provides a safe and convenient screening method for syphilis infections. The evaluation itself bears no significant risks.

However, the method of drawing blood and lumbar punctures can pose some minor complications.

Blood draws could cause:

  • tenderness or pain near the injection site
  • bruising or bleeding immediately after the procedure
  • dizziness
  • lightheadedness

Although rare, a lumbar puncture can cause the following complications:

  • a mild to severe headache
  • numbness or tingling in the lower back or legs
  • lower back or leg pain
  • bleeding
  • infections at the injection site

When to see a doctor

The United States Preventative Services Task Force (USPSTS) recommend screening for syphilis infections in the following populations:

A doctor may use a VDRL test to screen for syphilis if someone:

  • has symptoms of syphilis
  • has recently been treated for syphilis
  • believes they may have had exposure to T. pallidum
  • is currently receiving treatment for another STI
  • engages in sexual activity without the use of barrier contraceptives

A person should get tested for syphilis if they experience the following symptoms.

  • The appearance of a chancre: This is a painless, round, firm sore. The chancre will heal after 3–6 weeks, even if a person does not receive treatment.
  • The appearance of rashes or sores: The rash may be red and rough, and sores may appear on areas of the body.

Other symptoms may include swollen lymph glands, fever, hair loss, weight loss, and headaches.


Symptoms of syphilis vary according to the stage of the disease.

Primary Stage

A chancre appears during the primary stage of syphilis. It will appear where the infection entered a person’s body.

If a person does not receive treatment, syphilis will develop into the secondary stage.

Secondary stage

This is when skin rashes and lesions appear. They may occur in the vagina, the anus, or the mouth.

The rashes are not typically itchy.

A person may also develop a fever, muscle aches, swollen lymph glands, sore throat, and hair loss.

Latent Stage

No symptoms of syphilis appear in this stage.

Tertiary Syphilis

This stage can be fatal and typically occurs between 10–30 years after the initial infection.

It can affect the brain, eyes, heart, blood vessels, joints, and bones.

The symptoms may vary depending on which organ the syphilis is affecting.

Neurosyphilis and Ocular Syphilis

This may happen at any stage of the infection. Ocular syphilis affects the body, and neurosyphilis affects the nervous system and the brain.

Signs include anxiety, fatigue, depression, physical function issues and behavioral changes.


Doctors and other healthcare providers can screen for syphilis using the VDRL test. Syphilis is an STI resulting from T. Bacterium pallidum.

Antibodies that kill bacteria and other potentially harmful microbes are produced by the body’s immune system.

The VDRL test measures how many antibodies are present in the blood or spinal fluid of a person.

A health care provider will need to collect blood or a sample of spinal fluid to perform the test.

These procedures can cause minor side effects near the injection site, such as headaches, bruising and soreness.

Those who most likely have negative outcomes don’t have syphilis. Nevertheless, if someone has a recent exposure or has a high risk for syphilis, a doctor might suggest repeating the test at a later date.

Early detection of syphilis will lead to better, more effective treatment outcomes.

Early treatment reduces the risk of complications in the long term, which helps prevent further transmission.

Click to comment

Leave a Reply

Your email address will not be published.

eleven + 12 =

Blood / Hematology

Types and normal ranges of kidney function tests



Kidney function tests are basic procedures that use blood or urine to diagnose kidney abnormalities. A variety of kidney function tests are available to assess various aspects of renal health.

A kidney function test can detect sluggish waste filtering. Another test may detect protein leakage from the kidneys.

In cases where a doctor suspects a kidney disease, routine testing can help all individuals.

According to the National Kidney Foundation, 1 in 3 adults in the US is at risk for kidney disease, and many early cases show no symptoms. It’s important to detect and treat this condition early to avoid permanent damage.

In this article, you’ll learn about kidney function tests and their results.

What is it?

consulting a doctor

Kidney function tests use blood or urine to assess many elements of kidney health.

Doctors frequently request multiple tests to provide a comprehensive picture of kidney health.

The kidneys are vital to the body’s wellbeing. Their major function is to filter waste from the blood and excrete it in the urine.

Kidney disease can hinder the kidneys from filtering waste effectively, causing hazardous symptoms.

Regular testing may help detect disorders like kidney disease early on, halting its disease.

Doctors may also arrange imaging or a biopsy to learn more about the kidney.

Continue reading to learn about kidney function testing.

Urine tests

Pee tests may demand a little sample or all of a person’s urine in 24 hours.


Urinalysis helps doctors uncover underlying disorders or decide which test to employ next. Urinalysis can discover unwanted particles in urine such as:

  • sugar
  • protein
  • pus
  • blood
  • bacteria

A positive test for one or more of these particles means:

The microalbuminuria or albumin-to-creatine ratio

Both tests require a little urine sample. Both aid in detecting albumin in urine.

Albumin is an important protein in the blood. Not doing your job properly if your kidneys excrete too much albumin.

30 mg/g or less urine albumin is normal. Any higher may indicate renal disease.

As a result, microalbuminuria can detect even minute levels of protein in the urine.

Even if other urine protein tests are negative, people at increased risk of renal disease may need a microalbuminuria test.

Creatine clearance

A creatine clearance test involves both blood and urine. It entails taking a 24-hour urine sample and a blood sample.

Creatine is a naturally occurring waste product in the body from muscular use.

Doctors compare creatine levels in urine to blood levels. This chart compares the amount of waste the kidneys filter out, which may indicate their general health.

Blood tests

An arm blood test requires a doctor or nurse to extract a little amount of blood from the patient. The person may need to fast or take the test early in the morning.

Serum creatine test

Serum creatine levels that are excessively high could indicate that the kidneys aren’t doing their job properly. As part of the creatine clearance test, doctors will also prescribe a serum creatine test.

Serum creatine levels exceeding 1.2 for women and 1.4 for men, according to the National Kidney Foundation, may be an early warning that the kidneys aren’t working properly. As renal disease advances, these figures may grow even higher.

This test can also be used to calculate a person’s glomerular filtration rate (GFR) to confirm a diagnosis or to order additional tests to double-check the results.

The GFR test adjusts the findings of a serum creatine test for a variety of parameters, including age, gender, and race. A GFR of 60 or higher is considered normal. A GFR of 60 or less is indicative of renal disease.

Blood urea nitrogen test

The blood urea nitrogen (BUN) test looks for urea nitrogen and other waste products in the blood.

When proteins in food break down, urea nitrogen is produced, and high amounts may indicate that the kidneys are not filtering these waste products adequately.

BUN levels typically range from 7 to 20 milligrammes per deciliter. Higher levels could indicate a kidney-related underlying condition.

However, numerous other factors, such as drugs or antibiotics, might impact BUN levels. A diet high in protein may also have an impact on levels.

To acquire a better picture of how successfully the kidney filters this waste, doctors would often compare these results to the results of a creatine test.

Imaging tests

Imaging scans may aid in the detection of any physical abnormalities to the kidneys, such as injuries or kidney stones.


To take photos, ultrasound exams use innocuous sound waves. An ultrasound may be ordered by a doctor to check for changes in the shape or position of the kidneys. An ultrasound may also be requested to screen for tumours or obstructions, such as kidney stones.

CT scans

A CT scan is a procedure that employs a sequence of X-ray images to build a 3D image of the kidneys. It could aid in the detection of any structural alterations or deformations in the kidney.

A dye injection is sometimes required for the scan, which might be problematic for people who have kidney disease.


Doctors may recommend a kidney biopsy in some instances. This is a procedure in which a tiny needle is inserted into the kidney to remove renal tissue. The tissue will be sent to a lab for testing by the doctor.

When doctors need to diagnose a specific disease and determine how well it might react to treatment, they may perform a biopsy. A biopsy may also be used to assess the progression of renal disease.


Multiple positive test findings indicate that there is a problem with the kidneys.

Each of these tests provides doctors with a more complete view of a person’s overall kidney health. The scans can also detect renal disease signs, allowing for the ordering of additional tests.

Doctors will strive to completely identify the condition and design a treatment strategy once they have determined that there is a problem with the kidneys.

Kidney failure can be caused by a variety of underlying diseases. In order to discover the best treatment for each instance, a comprehensive diagnosis is required.


Renal function tests are an important element in diagnosing and treating kidney problems. Even if there are no symptoms, some people may need to be tested on a regular basis.

People at increased risk for kidney problems should get frequent kidney function testing, according to the National Institute of Diabetes and Digestive and Kidney DiseasesTrusted Source. Those with the following people are at a high risk:

Regular renal function testing can help detect kidney abnormalities early on, when the outlook is the best.

People can assist prevent the condition from progressing by sticking to a treatment plan. The best method to evaluate and manage any indicators of kidney damage or underlying issues is to work directly with a doctor.



Continue Reading

Cardiovascular / Cardiology

What is an echocardiogram?



An echocardiogram is an ultrasound image of the heart. It can help doctors diagnose a range of heart problems.

Doctors use echocardiograms to help them diagnose heart problems, such as damaged cardiac tissue, chamber enlargement, stiffening of the heart muscle, blood clots in the heart, fluid around the heart, and damaged or poorly functioning heart valves.

In this article, we explain how doctors use echocardiograms, what to expect during the test, and how to interpret the results.

What is it?


Ultrasound waves are used in echocardiography to create a picture of the heart, which is referred to as an echocardiogram (echo).

It is a minimally invasive medical technique that emits no radiation and has few negative effects.

A doctor can see the following things during an echocardiogram:

  • any blood clots in the heart
  • areas of damaged or weak cardiac muscle tissue
  • the size and thickness of the chambers
  • how the valves of the heart are functioning
  • problems affecting the pericardium, which is the fluid-filled sac around the heart
  • causes of a stroke
  • the direction of blood flow through the heart

Doctors frequently utilize echocardiography to assess a person’s overall heart health, particularly following a heart attack or stroke.

What is the procedure?

Echocardiograms are simple, noninvasive procedures that require little preparation.

We’ll go over what to expect before, during, and after an echocardiography in the sections below.


The person does not need to prepare if the echocardiogram is taken from the outside of the body by a healthcare expert.

A doctor will advise people who are getting a transesophageal echocardiography to avoid eating or drinking anything for at least 6 hours before the procedure. Following the local anesthetic wears off, people can resume eating and drinking 1–2 hours after the echocardiography.

During the test

The transthoracic (external) echocardiography will be performed by a sonographer. Sonographers are medical practitioners who specialize in producing images and movies for diagnostic purposes utilizing ultrasound instruments.

The person getting the echocardiography will take off their clothes from the waist up throughout the procedure. If they want to be covered during the exam, they can wear a hospital gown.

The sonographer will then urge the patient to lie on their back or left side on a table. They may inject a saline solution or dye into the veins of the patient to make the heart seem more distinct on an echocardiogram.

The type of echocardiography determines the procedure. Consider the following example:

Transthoracic echocardiogram

The sonographer will apply a gel to the chest if a doctor has ordered a transthoracic echocardiogram. After that, the sonographer will move the transducer across the chest to obtain various images of the heart.

The sonographer may ask someone to change positions or take or hold a deep breath throughout the examination. To gain a better view of the heart, they could press the transducer into the chest.

Transesophageal echocardiogram

If a clinician wants more detailed or sharper images of the heart than a transthoracic echocardiogram can provide, they may perform a transesophageal echocardiogram.

The person may be given a small sedative to help relax the muscles in their throat and a topical anesthetic to block the gag reflex during a transesophageal echocardiogram.

A doctor will guide a small transducer on the end of a long tube down the throat and esophagus until it reaches the back of the heart once the sedative and local anesthetic have taken effect.

As the doctor moves the transducer around the esophagus, the sonographer will record images of the heart. After swallowing the probe, the user should not feel the transducer or tube in their esophagus.

After the test

After a transthoracic echocardiography, most people can resume their normal activities.

After a transesophageal echocardiography, people may be required to stay at the hospital or healthcare center for a few hours. They may have a sore throat at first, but it should go away within a day or two.

If you were given a sedative prior to the exam, you should not drive for many hours afterward.

What does it diagnose?

Echocardiograms allow doctors to see the size, structure, and activity of different parts of the heart.

This allows them to identify heart abnormalities, assess the need for additional tests, decide their next actions, and monitor changes and improvements.

Doctors may use this approach to examine for signs or symptoms that could indicate the following:

  • Heart attack: The test can look for anomalies in the heart muscle tissue’s blood supply, as well as wall irregularities and blood flow, all of which can signal a heart attack.
  • Blood clots (thrombus) or tumors: In a study published in 2021, echo was proven to be a viable alternative to cardiac magnetic resonance in detecting thrombosis. According to a 2020 study, it is also an important noninvasive method for detecting heart masses such as malignancies.
  • Atherosclerosis and coronary artery disease (CAD): While an echo cannot detect artery blockages, narrowing and obstructed arteries can impair the heart’s ability to pump blood and disrupt the heart’s wall motion. This is more noticeable during times of stress, making a stress echo a useful diagnostic tool.
  • Aortic aneurysm and aortic dissection: An echo can detect a wide, weaker aorta, as well as unruptured aneurysms and their size, as well as fibrosis and thrombus formation in the vessel.
  • Cardiomyopathy: The test can determine the size and function of the heart and link it to factors such as wall thickness, weak heart muscle, leaky heart valves, heart failure, and high blood pressure.
  • Pulmonary hypertension: The test can measure heart pressure, which can indicate the presence of pulmonary hypertension and aid doctors in determining the following steps in the diagnosis.
  • Congenital heart disease: In newborns and early children, the test can detect congenital cardiac problems such as septal defects and holes.
  • Heart valve disease: The test checks for leakage, constriction, infection, and blockage in heart valves, as well as irregular cardiac blood flow.
  • Problems with the pericardium: The test can determine whether the pericardium (the sac that surrounds the heart) is inflamed (pericarditis) or has become filled with fluid or blood (pericardial effusion).
  • Heart failure: It can detect cardiac muscle that is weak, stiff, or thickened, which can be a symptom of heart failure.

Doctors frequently utilize the test to determine the cause of an abnormal electrical heart test, known as an electrocardiogram (EKG).

The method is also used to track how effectively the heart responds to various heart treatments, such as heart failure, drugs, prosthetic valves, and pacemakers.

If a doctor suspects a patient has cardiac abnormalities, an echocardiography will be ordered. The following are signs and symptoms that could suggest a cardiac condition:

Types of echocardiogram

Different types of echocardiograms are available, all of which use high-frequency sound waves. The following are some of the most frequent types.

The most common form of echocardiography is the transthoracic echocardiogram.

An ultrasound wand called a transducer is placed on the outside of the chest, near the heart, for this test. Sound waves are sent through the chest and into the heart via the device.

Sound waves move more easily when a gel is applied to the chest. These waves bounce off the heart and appear on a screen as images of the heart’s architecture.

Transesophageal echocardiogram

A thinner transducer attached to the end of a lengthy tube is used in a transesophageal echocardiogram. The tube will be swallowed and inserted into the esophagus, which connects the mouth to the stomach and runs behind the heart.

Because it gives a “close up” view of the heart, this type of echocardiography produces more detailed images of the heart than the typical transthoracic echocardiogram.

Doppler ultrasound

Doppler ultrasounds are used by doctors to check blood flow. They accomplish this by producing sound waves at specified frequencies and observing how the waves bounce off and return to the transducer.

Color doppler ultrasounds can be used by doctors to map the direction and velocity of blood flow in the heart. The blood flowing toward the transducer shows red, while the blood flowing away appears blue. It can also tell you how bad the blockages are.

A doppler ultrasound can detect issues with valves or holes in the heart’s walls, as well as let doctors examine how blood flows through it.

3D echocardiogram

A detailed 3D image of the heart is created through a 3D echocardiography. 3D echocardiograms can be used by doctors to:

  • plan heart valve or structural interventional surgery
  • image complex structures within the heart
  • assess valve functionality in people who have heart failure
  • assess the function of the heart in 3D
  • diagnose heart problems in infants and children

Stress echocardiogram

A doctor can order an echocardiogram as part of a stress test. A stress test involves physical exercise, such as walking, jogging on a treadmill, or riding a bike.

During the test, the doctor will keep track of your heart rate, blood pressure, and electrical activity in your heart.

Before and after the activity, a sonographer will do a transthoracic echocardiogram.

Stress tests are used by doctors to diagnose:

Point-of-care (POC) echocardiogram

A POC echocardiogram is a type of echocardiogram that can be performed at a patient’s bedside by a clinician. These can assist a doctor in answering specific inquiries about possible differential diagnoses.

Limited and focused POC echo are the two types of POC echo.

A limited echocardiogram aids a clinician in determining the cause and repercussions of a heart injury. A focused echo is used by a doctor to assist narrow down the list of other possible diagnoses or to answer a specific query.

With each heartbeat, a POC echocardiogram can determine how well the left or right ventricles pump blood.

Fetal echocardiogram

A fetal echocardiogram allows doctors to see the heart of an unborn baby. This check is normally done between 18 and 22 weeks of pregnancy. Because echocardiograms do not involve radiation, they are safe for both the mother and the infant.

Interpreting the results

The echocardiographic images will be sent to the doctor who requested the test by the sonographer after the exam. The doctor will examine the photos for indicators of cardiac disease, such as:

  • abnormal chamber size
  • poorly functioning valves
  • chamber size
  • masses in the heart, such as blood clots or tumors
  • damaged heart muscle tissue
  • pumping function of the heart
  • thick or thin ventricle walls

What can it miss?

Echocardiograms are very useful in detecting structural heart abnormalities. They may, however, not be the ideal way to check the coronary arteries.

Blockages can cause the structure of the heart. Changes in cardiac function, weak muscles, or thinner heart walls are frequently detected by doctors, prompting them to order additional tests such as a coronary angiogram.

Echocardiograms cannot detect conduction disorders or electrical difficulties that impact the heart’s rhythm, but they can measure the effects of these abnormalities on the heart.

Echocardiogram vs. electrocardiogram

An echocardiogram should not be confused with an electrocardiogram, or EKG, which is another diagnostic procedure. The electrical impulses or waves that flow through cardiac muscle tissue are measured by an EKG.

The electrical activity in the heart causes the heart muscle tissues to contract and relax, resulting in the rhythmic heartbeat that a stethoscope can detect.

Electrodes are placed on the skin of the chest, arms, or legs by a qualified technician, nurse, or doctor. These electrodes capture electrical activity and transfer it to a computer, which translates it into a graph that a doctor may see.

Are there any side effects?

An echocardiogram has a very minimal risk of problems or side effects. When the sonographer guides the tube down the throat during a transesophageal electrocardiogram, the person’s gag reflex may be triggered. After the exam, some people may experience a sore throat.

A significant consequence, such as injury to the throat, vocal cords, or esophagus, can occur very rarely as a result of the transesophageal echocardiogram.

Some people may have an adverse reaction to local anesthetics, sedatives, contrast dyes, or saline used during the exam. Only use contrast dyes if absolutely essential when pregnant.

The following are some of the potential negative effects of contrast dyes:

During a stress test, some people may experience changes in blood pressure or a reduction in oxygen delivery to the heart. In the event that a person has any issues during the assessment, a stress test will be performed in a fully equipped medical facility.

When a person is given sedatives, the stomach contents have a risk of entering the lungs. To avoid this, the patient will be asked to come to the surgery on an empty stomach.


Doctors utilize echocardiography to diagnose heart-related issues. A doctor will assess how well a person’s heart pumps blood during the test.

Doctors can also use echocardiography to check for indicators of cardiac disease such weak heart muscle, blood clots inside the heart, or malfunctioning heart valves.

An echocardiogram may be ordered by a clinician if a patient exhibits symptoms of heart disease, such as:

  • heart murmurs
  • irregular heartbeat
  • shortness of breath
  • abnormal blood pressure
  • leg swelling

The test has a low risk of serious problems or side effects in general. However, some people may have discomfort, and other people may be allergic to the contrast material or anesthesia.



Continue Reading

Blood / Hematology

TSH levels: All you need to know



Thyroid-stimulating hormone (TSH) testing determines the level of TSH in the blood. The results show how well a person’s thyroid is working.

TSH test results can be used by doctors to diagnose thyroid problems such as hypothyroidism and hyperthyroidism.

TSH, a hormone that stimulates the thyroid gland, is produced by the pituitary gland.

The thyroid gland is a butterfly-shaped gland located in the throat. It secretes hormones that aid in the regulation of various biological systems, including metabolism, heart rate, and body temperature.

The TSH test and its findings are described in this article. We also go over what high and low TSH values mean and what therapies are available.

Typical TSH range

MNT-infographic_guide infographic by Diego Sabogal 1401179-TSH-levels-original
MNT-infographic_guide infographic by Diego Sabogal 1401179-TSH-levels-original

The typical range is determined by a person’s age and whether or not she is pregnant.

As a person gets older, the ranges tend to widen. TSH levels in males and females have not been found to differ consistently in studies.

However, doctors generally consider levels to be within a normal range of 0.4–4.0 milliunits per liter (mU/l), according to the American Thyroid Association.

TSH levels that are normal, low (showing hyperthyroidism), and high (indicating hypothyroidism) are estimated in the table below:

HyperthyroidismNormalMild hypothyroidismHypothyroidism

These reference values are often used in laboratories.

These ranges, however, are subject to some disagreement. According to the author of a 2016 review, normal levels are more likely to be in the range of 0.5–2.5 milli-international units (mIU) per milliliter.

TSH levels by sex

Females are more likely than guys to suffer from thyroid problems. According to the Office of Women’s Health, one out of every eight females will encounter thyroid difficulties at some point in their lives. Hyperthyroidism and hypothyroidism are examples of this. Thyroid disorders are more common during pregnancy and around menopause.

TSH levels in males and females do not differ consistently, according to research. TSH levels are usually greater in females, according to some data. TSH levels are greater in females, according to 2020 studies of Chinese and French populations, although other factors, including as age, are more likely to alter TSH levels.

Thyroid problems have been connected to sexual dysfunction in certain people. Males may be affected more than females. According to a 2019 study, 59–63 percent of male hypothyroidism patients also suffer sexual dysfunction, compared to 22–46 percent of female hypothyroid patients.

TSH levels by age

Blood TSH levels tend to rise as people age, with research indicating that hypothyroidism is the most frequent thyroid condition in people over 60, and that it rises steadily with age.

According to research involving older persons, between 7–14 percent of people may have TSH levels over the upper limit of reference ranges.

Normal TSH levels in pregnancy

Pregnancy hormones naturally raise blood levels of some thyroid hormones. This is necessary for the unborn brain and nervous system to grow.

TSH levels in the blood decrease at the same time. As a result, during pregnancy, doctors adopt lower reference ranges. The lower TSH range is reduced by about 0.4 mU/l, while the higher limit is reduced by around 0.5 mU/l.

TSH levels in the blood steadily rise during the second and third trimesters, but they remain lower than in non-pregnant women.

TSH levels are carefully monitored by doctors throughout pregnancy. Having abnormally high or low levels might cause the risk of miscarriage and lead to pregnancy-related problems such as:

Normal TSH levels in children

TSH levels peak at birth and progressively decline as a child grows older. As a result, TSH levels can differ amongst children. After the newborn period, health professionals may describe moderate hypothyroidism in children as TSH levels ranging from 4.5 to 10 mU/l.

According to an older study that included data from 512 healthy children, the following table depicts TSH levels for children by age:

AgeReference ranges (mU/l)
Day of birth3.84–11.75
1 month1.18–3.57
1 year1.17–3.55
5 years1.15–3.47
12 years1.09–3.31
18 years1.05–3.16

What exactly do high levels imply?

TSH levels that are too high indicate hypothyroidism. When the thyroid produces insufficient hormones, people suffer hypothyroidism.

When a person’s thyroid gland does not generate enough hormones, the pituitary gland increases TSH production to compensate.

Hypothyroidism symptoms may include:

  • irregular or heavy menstrual periods
  • fertility problems
  • depression
  • constipation
  • fatigue
  • increased sensitivity to cold temperatures
  • dry skin
  • weight gain
  • swelling of the face and neck
  • thinning hair
  • a slow heart rate

What exactly do low levels imply?

TSH levels that are too low indicate hyperthyroidism. This is also referred to as an overactive thyroid.

When a person’s thyroid gland secretes high amounts of hormones, the pituitary gland generates less TSH.

Hyperthyroidism can cause the following symptoms:

  • difficulty sleeping
  • frequent bowel movements or diarrhea
  • weight loss
  • mood changes
  • irregular or rapid heartbeat
  • muscle weakness
  • nervousness or irritability

How to measure TSH levels

A healthcare practitioner will draw blood from a vein in the inner arm for the TSH test. They then submit the blood sample to a laboratory for analysis.

Typically, people do not need to prepare for a TSH test. If the doctor is screening the blood for more than one problem, the patient may need to fast or prepare in another way. This information will be provided by the doctor ahead of time.

A TSH test is frequently the most accurate approach to assess thyroid function. If a person’s TSH levels are excessively high or low, the doctor may need to run at least one further diagnostic test to determine the underlying cause. Specific thyroid hormones and antibodies are measured in these assays.

Factors influencing levels

TSH levels can be affected by a variety of circumstances, including age, sex, and pregnancy. TSH levels may be affected by genetic, environmental, or intrinsic causes, according to evidence. Some of these elements could be:

  • time of day and time of year
  • autoantibodies and heterophilic antibodies
  • smoking
  • pollutants
  • other conditions occurring at the same time
  • medications
  • supplements
  • ethnicity
  • diet and iodine status

Hypothyroidism treatment (high TSH levels)

Doctors can treat hypothyroidism with drugs that restore the missing thyroid hormones, such as levothyroxine.

This drug should be taken once a day or as directed. Every few months, the doctor will do further blood tests to see how well the medicine is working.

People should take levothyroxine once a day, on an empty stomach, at least half an hour before eating, according to the Food and Drug Administration (FDA).

The FDA also advises people to notify their doctor if they consume soybean flour, walnuts, dietary fiber, or cottonseed meal, as these foods can alter how the body uses levothyroxine. Drinking grapefruit juice may also delay levothyroxine absorption.

Treatment of hyperthyroidism (low TSH levels)

Treatment for hyperthyroidism focuses on lowering thyroid hormone levels in order to avoid long-term health consequences.

Beta-blockers and antithyroid medicines may be required.

Radioiodine therapy is another successful treatment. This entails ingesting a capsule or liquid containing radioactive iodine-131, which destroys thyroid hormone-producing cells. People who receive radioiodine therapy, on the other hand, may develop hypothyroidism in the future.

Severe hyperthyroidism can be treated surgically by removing the thyroid gland. Doctors frequently reserve this for patients who are unable to take first-line drugs or who have severe hyperthyroidism.


A TSH test determines the level of the hormone in the blood. The results can be used by doctors to diagnose thyroid problems such as hypothyroidism and hyperthyroidism.

Normal TSH readings can vary greatly based on age, sex, and weight. TSH reference ranges are still debatable, however for most people, the typical range is between 0.4 to 4.0 mU/l.

A thyroid that is overactive or underactive might cause health problems that interfere with a person’s daily life. TSH levels that are extremely high or low during pregnancy can cause difficulties.

More information about the TSH test and interpreting the findings can be obtained from a doctor.



Continue Reading

Copyright © 2022