Question: how do you know the names of the diseases?

Nina Rzechorzek answered on 29 Apr 2020: last edited 28 Apr 2020 11:35 pm

This is such an important question – especially for brain diseases. If you can be sure about the underlying cause of a disease (e.g. a specific genetic mutation, or a specific pathogen such as virus) it is much easier to give it a name. This is pretty relevant to the current pandemic, where the pathogen (the virus) and the disease it causes are named as follows:
Virus = COVID-19
Disease = severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)
where ‘severe’ = really bad, ‘acute’ = sudden onset, ‘respiratory’ = affecting the lungs, and ‘syndrome’ = a number of symptoms occurring together and characterizing a specific disease
This page explains how these names were determined:
https://www.who.int/emergencies/diseases/novel-coronavirus-2019/technical-guidance/naming-the-coronavirus-disease-(covid-2019)-and-the-virus-that-causes-it
Now back to the brain – what if you cannot name the disease until after death? This is the case for many chronic brain disorders – particularly the age-related neurodegenerative disorders such as Alzheimer’s disease. Often an official diagnosis can only be reached once a specialist called a ‘neuropathologist’ has looked at the patient’s brain tissue under a microscope – and that can only happen after death. Before that time a ‘likely’ or ‘probable’ diagnosis is made based on the symptoms of the patient and the progression of these symptoms. Some symptoms are measured using cognitive tests (tests of brain function such as memory); other tests to support a diagnosis include brain scans. Question then arise: who determines the diagnosis? Who gives the disease a name? Is it the doctor performing the cognitive tests or the neuropathologist looking down a microscope? Often, until a definitive diagnosis is made, patients are told they have ‘dementia’. ‘Dementia’ is not a diagnosis, it is ‘a word used to describe a group of symptoms including memory loss, confusion, mood changes and difficulty with day-to-day tasks’ and it can have a number of underlying causes. See this page for more info:https://www.alzheimersresearchuk.org/dementia-information/?gclid=CjwKCAjwqJ_1BRBZEiwAv73uwMl-PxBTZbbQViuJEbD1Asm9b8HqnOlAcXqzU4FSOEcouUUDEM6RrRoCwa4QAvD_BwE
Although it can be difficult to give a disease an official name, having a diagnosis is often very important to the patient – if they can name their disease, they are empowered to rationalise and understand their symptoms (even if there may be no effective treatments for some diseases currently). Incidentally, many diseases are named after the person who first described them e.g. Alzheimer’s disease, Parkinson’s disease, Huntington’s disease, Creutzfeldt-Jakob disease (CJD). Nowadays disease names tend to be more descriptive about the underlying pathology e.g. chronic traumatic encephalopathy (CTE) in sports, where ‘chronic’ = occurring over a long time, ‘traumatic’ = caused by trauma (in this case, repetitive trauma), and ‘encephalopathy’ = disorder or disease of the brain’.
Finally to clear up some definitions:
Disease = a particular distinctive process in the body with a specific cause and characteristic symptoms.
Disorder = irregularity, disturbance, or interruption of normal functions.
Syndrome = a number of symptoms occurring together and characterizing a specific disease.