1. Same Symptoms, same disease, same treatment?

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Patients that are diagnosed with the same disease have generally been thought to have the same root cause. Doctors therefore often give these patients the same treatments. However, clinical experience tells us that patients do not all respond in the same way.

In reality, patients diagnosed with the same disease can have very different experiences with their disease. For example, the disease might develop slowly or quickly. It might be more or less severe or it might be chronic (long-term). In addition, different patients may respond very differently to the same treatment:

  • Some will respond well.
  • Some will respond, but less well.
  • Some will not respond.
  • Some may have serious side effects (adverse reactions).
  • Some may develop ‘resistance’ to the medicine (they stop responding) - this can happen even if they responded well at first.

Doctors try to take into account various clinical and lifestyle factors when they treat individual patients. However, often the only option is to try out a treatment, and monitor the patient’s response. If necessary, the dose, schedule or medicine can be changed.

Today, we know that these patients are probably affected by ‘different’ diseases. In other words, patients can show the same symptoms but the symptoms can be caused by different processes in their cells (they have a different underlying pathology). These differences can have a great effect on how a disease will progress, and which is the best treatment.

This is an important change in the way to diagnose and treat disease.