Should I Be Worried About a Repeat Blood Test?

medical worker picking up blood test vials

Has your doctor ordered a follow-up blood test after you have already done one? This is naturally quite worrying for many people, especially those worrying about a potential serious diagnosis.

The truth is that repeat blood tests are far more common than you might think, and they are usually nothing to worry about. Find out all you need to know about what a repeat blood test might mean and whether you should worry right here. Hopefully, it will ease your mind.

Understanding Blood Tests and What They Measure

Before diving into what a repeat blood test might mean, it helps to understand what blood tests measure in the first place.

Essentially, a blood test is a process in which your blood is closely analysed in a lab. What exactly gets measured depends on the type of blood test you are doing, with some common ones including:

Full Blood Count: Measures red blood cells, white blood cells, platelets, and haemoglobin.

Lipid Panel: Measures cholesterol and triglycerides.

Thyroid Panel: Measures thyroid hormones, including TSH, T3, and T4.

Liver Function Tests: Measures proteins and enzymes that are produced in the liver.

So, if you have done a full blood count test, this can be used to investigate your blood cells to check for overall and general health issues, which are particularly common when individuals show symptoms like fatigue and bruising. If you have done a thyroid panel, it’s to investigate the potential of hypothyroidism or hyperthyroidism.

Is a Repeat Blood Test a Bad Sign? Should You Be Worried?

One of the most common questions doctors hear after ordering a repeat blood test is, “Should I be worried about repeat blood test?”. The truth is, there are so many variables, so it’s hard to say what the reason behind the repeated blood test is. However, there are some very common reasons a repeat blood test is necessary, many of which are not anything to worry about. So, it is best not to fret; instead, follow your doctor’s instructions and rest assured that there are many reasons for a repeat blood test that do not indicate anything medically serious.

5 Reasons a Repeat Blood Test is Needed

These are the most common reasons a repeat blood test is needed.

1. Abnormal Results from the Blood Test

This is the potential reason that most people worry about. In some cases, a repeat blood test is necessary because of abnormal results. The blood test may have detected something out of the ordinary. In the most serious and critical cases, patients may need to access immediate medical care. Keep in mind that this definitely is not always the case. Plus, abnormal results may be worrisome, but there will likely be a treatment option to help you get back to good health.

2. Borderline Results

A very common reason for a repeat blood test is that the results are only slightly outside of the typical reference range. These borderline results require an additional blood test so that doctors can come to a clearer conclusion about your health and any potential treatments.

3. Compromised Samples

Samples sometimes get compromised; it happens. It may be because of not following the instructions properly, not collecting the right amount of blood, or samples getting mixed up in a lab.

Home test kits are very reliable, but make sure you follow the instructions to a T if you are doing it yourself.

If any samples are compromised, you will simply need to do another one.

4. Monitoring Conditions/Treatments

It is common for individuals with chronic conditions to need to do repeated blood tests. This is so that doctors can monitor your health over time. Also, if you start a new treatment, it’s normal for doctors to want to do a repeat blood test so they can see if the treatment is working or not.

5. Inconclusive Results

Oftentimes, a repeat blood test is necessary simply because the results were inconclusive. For doctors to reach an accurate diagnosis, the results need to be crystal clear. If that is not achieved on the first blood test, a follow-up test is needed.

Does the Timing Matter?

Yes – the timing of a repeat blood test matters. You can also gauge the potential reasons for a repeat blood test by looking at how quickly it is necessary.

Why repeat blood test in 3 months: A repeat blood test after around three months is usually to monitor long-term conditions or track the effectiveness of a treatment.

Why repeat blood test in 4 weeks: A repeat blood test after four weeks could be to monitor a new medication. It could also be to follow up on abnormal or inconclusive results.

Why repeat blood test in 2 weeks: Generally, this is to check borderline or abnormal results. However, it can be used to track trends, especially if it’s a liver or kidney function test.

Why repeat blood test in 2 days: This is usually done when monitoring conditions that can rapidly change, such as infections.

What to Do if You Need to Do a Repeat Blood Test

If you have been asked to do a repeat blood test, it is important to do it promptly and follow any instructions you have been given.

  • Stay Calm: Firstly, stay calm. Worrying about the potential reasons behind a repeat blood test will not help you in any way, and the chances are it will be okay. If you are worried during the blood test, be sure to tell your doctor about your concerns. You can also try some breathing exercises to ease your body and mind. For example, breathing in for four seconds, holding for seven seconds, and releasing for eight seconds.
  • Talk to Your Doctor: If you have any concerns at all, it is always best to talk to your doctor. You can ask them directly why they are repeating the blood test.
  • Follow Instructions: Remember to follow all of the instructions as closely as possible. If your doctor tells you to fast before the appointment, for example, make sure you do so for as long as you need to, as this will make sure the results are reliable.
  • Get the Repeat Blood Test: Do not avoid the appointment. This will only prolong the process. Your doctor has ordered a repeat blood test for a reason, so make sure you schedule an appointment at a time that suits you and attend it.

medical worker looking at blood test vials through a microscope

What Can a Repeat Blood Test Show?

In some cases, a repeat blood test is simply used to monitor a condition or new medication. In others, it shows that your levels are completely normal, and no more intervention is necessary.

However, there are also times when a repeat blood test may actually help diagnose a new condition.

  • Anaemia: Anaemia is a very common blood disorder that occurs when the blood does not have enough red blood cells or haemoglobin. A full blood count can show this.
  • Liver Dysfunction: Liver dysfunction is when the liver cannot perform all of its normal functions, such as filtering toxins and processing nutrients from food. Liver function tests are key to diagnosis.
  • Kidney Problems: A kidney function test can indicate kidney problems, such as kidney infections, injuries, kidney stones, and chronic kidney disease.
  • Diabetes: Diabetes refers to chronically high levels of glucose in the blood, and a HbA1c test can help with a diagnosis.
  • Infections: A blood test detects infections by looking specifically at the white blood cells in the blood. It can also help detect an infection by looking at inflammatory markers and pathogens.
  • Certain Cancers: A repeat blood test can, in some cases, detect certain cancers. This includes leukaemia, lymphoma, myeloma, prostate cancer, liver cancer, and pancreatic cancer.

When Should You Have a Blood Test?

You might wonder, how often should you have a blood test? It all depends on whether or not you are showing symptoms.

If you are a healthy adult under the age of 40, get a routine blood test every 2 to 3 years. If you are a healthy adult over 40, try to get one once per year, or at least every 2 years.

Then, if you show any symptoms, get a blood test as soon as you can to investigate why the symptoms might be there. It’s a key part of getting a diagnosis early.

What Happens if Your Blood Test Results Show an Illness?

If your repeat blood test indicates you have an illness, your doctor will likely perform some follow-up tests. Your doctor may investigate using your medical history, your family’s medical history, imaging tests, and a biopsy, for example. In some cases, you may be referred to a specialist doctor, for example, a haematologist who specialises in blood disorders.

Once a condition is accurately diagnosed, you will then begin a form of treatment. Of course, this treatment depends on the diagnosis. You might need to start a new medication or perhaps implement some lifestyle changes. You will likely also need to undergo more blood tests over time to monitor your condition.

Keeping Track of Your Health from Home

Do you want to have more control over your health? Perhaps your busy lifestyle means booking an appointment at your GP office is not so simple. If so, there is an easy way to track your health by using at-home blood test kits.

At Repose Healthcare, we offer a range of home test kits to help you understand your health on a deeper level. Doing one of these tests could be key to discovering an abnormality early, leading to a better medical outcome in the long run. They are simple to use, and you can find your results online within just three working days after sending back your sample.

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