The typical rare disease patient visits an average of 7.3 physicians before receiving a diagnosis.

Rare disease patients receive 2-3 misdiagnoses on average, each of which can involve unnecessary and invasive testing and administration of treatments that do not properly target the right disease.

Below, we'll explain four reasons why doctors have difficulty diagnosing rare diseases.

A Hispanic female patient who is covering her head

Rare Diseases & Lack of Awareness

  • Not only patients, but doctors also lack information about rare diseases

According to a study published by “The Economist” in 2020:

The EIU conducted a survey of 503 healthcare professionals from five countries in the Asia Pacific region during November and December of 2019. The purpose of this survey was to understand the level of understanding of rare diseases and current challenges of the healthcare system.

The participants of the survey included 172 current healthcare professionals, 40 nurses, 62 pharmacists, and 229 of the general population.

The distribution by country was as follows:

  • 103 in Australia
  • 100 in China
  • 100 in Japan
  • 100 in Korea
  • 100 in Taiwan.

Only 28% of healthcare professionals assessed their colleagues' knowledge level about rare diseases to be sufficient.

14% of the participants (10% healthcare professionals) stated that they had never encountered a rare disease patient during their career.

Difficulties in interpreting symptoms of rare diseases

  • Because symptoms can be complex and change over time, it is difficult to properly interpret them.
  • This can lead to a greater likelihood that the appropriate diagnostic tests are not used.
  • If inappropriate diagnostic tests are used that do not match the patients’ true condition, doctors will interpret inappropriate results causing an inaccurate diagnosis.


Newly Discovered Rare Diseases

  • With so many new rare diseases being continuously discovered, it is difficult for any medical professional to stay up to date on the latest findings
  • Based on data curated by Orphanet and Online Mendelian Inheritance in Man (OMIM), an average of about 260–280 rare genetic diseases are discovered per year.


Inadequate Insurance Coverage for Testing

  • Lack of insurance coverage for genetic tests is a source of problems for both patients and doctors, preventing the use of genetic tests.
  • Above everything, the high costs and procedural difficulties are the main reasons that the diagnostic odyssey of rare disease patients is so long.


Due to these reasons, despite the long and repeated efforts by medical staff to diagnose, rare disease patients end up visiting various hospitals without being diagnosed, leading to an endless diagnostic odyssey.

However, as technology advances it is becoming easier to end the diagnostic odyssey. With the price of NGS tests decreasing, whole exome sequencing (WES) is becoming more accessible.

With advanced AI technology, analysis of rare diseases has become more efficient; as we can now reflect the latest findings on genetic variants in real-time, the diagnostic rate continues to increase.

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