5 health conditions that are difficult to diagnose

We take a look at the journey behind a diagnosis of type 2 diabetes, coeliac disease, hypothyroidism, PCOS, and Lyme disease.

Some health conditions present differently from one person to the next and many share the same symptoms as another condition. Both of these factors can make it difficult to diagnose certain conditions.

It can take years and many trips to the doctor before some health conditions are diagnosed. At best, this leaves people with irritating or even disabling symptoms; at worst it means their condition progresses, bringing additional health risks and misery.

A reliable diagnosis is a crucial stage in any health journey, not only to ensure you receive the most effective and appropriate treatment, but a reliable diagnosis can provide long-awaited relief. After experiencing mysterious symptoms, a reliable diagnosis can provide an empowering explanation for your symptoms, especially if you’ve been proactive about your health and have been well-prepared for your visits to your GP.

Five common health conditions that can go un-diagnosed:

  1. Type 2 diabetes
  2. Coeliac disease
  3. Hypothyroidism 
  4. Polycystic ovary syndrome
  5. Lyme disease

1. Type 2 diabetes

Type 2 diabetes causes the amount of sugar in the blood to become too high [1]. Being overweight, aged 40 years or having a family history of type 2 diabetes, can considerably increase your chances of developing the disease.

Type 2 diabetes can be difficult to identify and is frequently only detected following tests for unrelated medical problems [1]. In the early stages, symptoms may not necessarily make you feel unwell, so many people have type 2 diabetes without realising it [1].

Symptoms of type 2 diabetes include:

  • Feeling thirsty all the time
  • Feeling tired
  • Losing weight without trying [1]
  • Urinating more often than usual, particularly at night

Diagnosing type 2 diabetes early is important because, if left untreated, the disease may lead to further health problems, such as nerve damage and vision loss.

Medichecks offers a simple Diabetes (HbA1c) Blood Test, which assesses your body’s ability to regulate blood sugar. HbA1c is a long-term measure of sugar attached to haemoglobin in red blood cells and is, therefore, a thorough and reliable evaluation which reflects your average blood sugar over months rather than just taking a snapshot at a particular point in time.

Lifestyle modifications, such as dietary changes and increasing physical activity, are important in managing type 2 diabetes. Encouragingly, if diagnosed in the early stages, type 2 diabetes may be reversed through weight loss but speak to your GP before making any extreme lifestyle changes.

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2. Coeliac disease

It is estimated that over 500,000 people in the UK live with undiagnosed coeliac disease [2] and sadly, the average time to diagnosis is 13 years [3]. Coeliac disease is an autoimmune disease triggered by the consumption of gluten (found in foods containing wheat, barley and rye), which causes the body to attack its healthy tissues [4].

Coeliac disease can impair the body’s ability to absorb nutrients from foods [5] and lead to distressing symptoms such as:

  • Bloating and flatulence
  • Diarrhoea Abdominal pain
  • Prolonged fatigue [4]
  • Unexpected weight loss

Coeliac disease may be difficult to diagnose for several reasons. Firstly, symptoms are not specific and may overlap with other health conditions such as the more common condition of irritable bowel syndrome (IBS) [6].

You may have noticed a gluten sensitivity, and therefore (understandably) have excluded it from your diet. However, excluding gluten from your diet may cause false-negative test results [5], as your body doesn’t produce antibodies to gluten if you haven’t eaten gluten, so there is nothing to be detected in a blood test.

Coeliac disease

Diagnosing coeliac disease, even if you or your doctor suspects it, is further complicated by the fact that there is no simple test for it. You may be required to have a whole series of tests which means introducing gluten back into your diet on many occasions. When you read the list of symptoms above, you can see that this is not a pleasant experience for people with coeliac disease.

Other diagnostic methods include having an endoscopy and biopsy, whereby a tissue sample is collected from the digestive tract [4], this is often used to confirm a diagnosis when a blood test suggests coeliac disease. Whilst having an endoscopy and biopsy can be uncomfortable, it is rarely painful.

It is important to diagnose coeliac disease, as left untreated, it may lead to nutritional deficiencies and/or other complications such as osteoporosis and cancer [4]. Reassuringly, once a positive diagnosis has been made, many people can manage their symptoms successfully by excluding gluten from their diet. Your GP may also recommend a nutritional supplement, such as vitamin B12, to compensate for any gaps in nutrient absorption.

Our Complete Coeliac Blood Test is where the laboratory performs the succession of tests required (if indicated) from a single blood sample. Coeliac blood tests often just look for transglutaminase IgA antibodies, but these can miss coeliac disease in people with selective IgA deficiency. Selective IgA deficiency is the most common primary antibody deficiency and is more common in people with coeliac disease. The Complete Coeliac Blood Test will perform a different, more appropriate test if selective IgA deficiency is suspected. Nutritional tests for Iron and Vitamin B12 are also available to investigate whether you are absorbing enough nutrients.

3. Hypothyroidism

The body’s thyroid gland produces hormones called triiodothyronine (T3) and thyroxine (T4), which regulate our metabolism. Hypo- means ‘less than normal’, and therefore individuals with hypothyroidism do not produce enough thyroid hormones [7] and experience a slow metabolism.

This may lead to symptoms such as:

  • Depressive symptoms
  • Excessive hair growth on the body [7]
  • Low energy and tiredness
  • Weight gain

Hypothyroidism can affect anybody, although it is more common in women [7]. Thyroid UK states that it can take 20 years to diagnose hypothyroidism and further studies have shown that it can take 6 to 12 visits to a GP before diagnosis [8].

Hypothyroidism is often difficult to diagnose because it can develop slowly and may not be noticed for years [7] and many of the symptoms can be confused with other conditions.

Importantly, the seemingly superficial ‘cosmetic’ distress caused by weight gain and hair growth may be overlooked, which can be frustrating and distressing and can lengthen the time to diagnosis.

Furthermore, the symptoms are wide-ranging; one individual may experience a collection of entirely different symptoms than another. For example, weight changes are not always present [9]. As a further challenge, some symptoms are similar to nutritional deficiencies. For example, an iron deficiency can also cause fatigue [10].

Experiencing hypothyroidism can be debilitating. A reliable diagnosis is essential to receive the most relevant help in managing the condition and avoiding future health complications. After receiving a positive diagnosis, hormone replacement therapy can help many people lead happy and healthy lives.

Thyroid condition

Medichecks offers a first-stage Thyroid Function Blood test to measure how well your thyroid is working. You may also be interested in taking an advanced blood test (Advanced Thyroid FunctionBlood Test) to measure thyroid function and other nutritional markers (vitamin D and iron), to investigate the underlying source of your symptoms. Testing your Selenium and Iodine status could also be valuable.

4. Polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is thought to affect 1 in 10 women in the UK [13], making it one of the most common female reproductive disorders.

This condition causes fluid-filled sacs to develop on the ovaries, which may lead to ovulation problems, hormonal imbalances, and the following symptoms: Irregular or missing periods Acne Weight gain Excess hair growth on the body Difficulty getting pregnant [13]

The cause of PCOS is unknown, and there is no one specific test [13], so it may be difficult to diagnose. Many symptoms can also overlap with other conditions (See symptoms of Hypothyroidism). Doctors may investigate your medical history, and sometimes a pelvic exam may be performed, or an ultrasound, to check for abnormalities [13]. As ultrasounds are not recommended for adolescents due to the normal occurrence of multi-follicular ovaries during this stage of life, this can create another obstacle in the diagnosis process [14]

A blood test is often a valuable and relatively non-invasive investigation, as it can check that specific sex hormones fall within normal ranges, particularly the male hormone testosterone, which may be in excess for women with PCOS [14].

If experiencing symptoms of PCOS, it is important to get this checked as PCOS can lead to health problems in later life, such as type 2 diabetes and cardiovascular disease [13]. Getting a diagnosis will enable effective treatments and lifestyle changes to manage often troubling symptoms and reduce the risk of future health conditions.

Medichecks offers a number of different blood tests to investigate PCOS, such as the Polycystic Ovary SyndromeBlood Test.

5. Lyme disease

Lyme disease is a common bacterial disease transmitted through infected ticks [15]. Ticks are spider-like creatures that live in long grass and wooded areas all over the UK [15]. After biting, ticks extract blood from the host, but in some cases, a bacterium can enter the bloodstream, leading to Lyme disease.

Lyme disease’s most obvious symptom is a circular, bulls eye-like, red rash that develops around a tick bite area. It may not be easy to connect this symptom back to a tick bite, as there is often a delay between being bitten and rash development – sometimes up to three months [15]. Many people may not even notice that they have been bitten, as ticks excrete a natural anaesthetic. In 2019, it was found that the number of new cases of Lyme disease in the United Kingdom was about three times higher than previously thought [16].

If you develop this characteristic rash at any time following a suspected tick bite, arrange to see your GP immediately, as you likely have Lyme disease and will need treatment as soon as possible [17].

Not everyone who develops Lyme disease will have a rash; some may experience flu-like symptoms such as high temperature and muscular pain, which could be misinterpreted as a health condition such as a seasonal virus. If a rash is not present, blood tests are currently recommended to investigate Lyme disease [17].

Symptoms of Lyme disease impact daily life and can persist for a long time [15]. If left untreated, the infection may spread and lead to health problems such as arthritis and heart problems [17]. However, after diagnosis, antibiotics may be provided, and most fully recover [15].

Our at-home Lyme Disease (ELISA) Blood Test investigates the presence of antibodies associated with having had Lyme disease.

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  1. NHS. Type 2 diabetes. Health A to Z 2020 [cited 2020 12th October]; Available from: https://www.nhs.uk/conditions/type-2-diabetes/.
  2. Mustalahti, Kirsi, et al., The prevalence of celiac disease in Europe: results of a centralized, international mass screening project. Annals of medicine, 2010. 42(8): p. 587-595.
  3. UK, Coeliac. Myths about coeliac disease. [cited 2020 12th October]; Available from: https://www.coeliac.org.uk/information-and-support/coeliac-disease/about-coeliac-disease/myths-about-coeliac-disease/.
  4. NHS. Coeliac disease. Health A to Z 2019 [cited 2020 24th August]; Available from: https://www.nhs.uk/conditions/coeliac-disease/.
  5. NICE. Coeliac disease: recognition, assessment and management. 2015 [cited 2020 24th August]; Available from: https://www.nice.org.uk/guidance/ng20.
  6. UK, Coeliac. About coeliac disease. 2020 [cited 2020 24th August]; Available from: https://www.coeliac.org.uk/information-and-support/coeliac-disease/about-coeliac-disease/.
  7. NHS. Underactive thyroid (hypothyroidism). Health A to Z 2018 [cited 2020 24th August]; Available from: https://www.nhs.uk/conditions/underactive-thyroid-hypothyroidism/.
  8. Gibbons, Veronique, et al., Investigating the pathways in primary practice leading to the diagnosis of central hypothyroidism. NZ Med J, 2012. 125(1364): p. 83-90.
  9. Portmann, Luc and Vittorio Giusti, Obesity and hypothyroidism: myth or reality? Revue medicale suisse, 2007. 3(105): p. 859-862.
  10. NHS. Iron Deficiency Anaemia. Health A to Z 2018 [cited 2020 24th August]; Available from: https://www.nhs.uk/conditions/iron-deficiency-anaemia/.
  11. Jackson, Malcolm J, Caroline S Broome, and Francis McArdle, Marginal dietary selenium intakes in the UK: are there functional consequences? The Journal of nutrition, 2003. 133(5): p. 1557S-1559S.
  12. Zimmermann, Michael B, Iodine deficiency. Endocrine reviews, 2009. 30(4): p. 376-408.
  13. NHS. Polycystic ovary syndrome. Health A to Z 2019 [cited 2020 24th August]; Available from: https://www.nhs.uk/conditions/polycystic-ovary-syndrome-pcos/.
  14. NICE. What investigations should I arrange? Polycystic ovary syndrome 2018 [cited 2020 24th August ].
  15. NHS. Lyme Disease. Health A to Z 2019 [cited 2020 24th August]; Available from: https://www.nhs.uk/conditions/lyme-disease/.
  16. Cairns, Victoria, et al., Incidence of Lyme disease in the UK: a population-based cohort study. BMJ open, 2019. 9(7): p. e025916.
  17. NICE. Lyme Disease NICE guidelines [NG95]. 2018 [cited 2020 24th August]; Available from: https://www.nice.org.uk/guidance/ng95.

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