As you may know, dysautonomia is not a specific medical diagnosis. Dysautonomia is an umbrella term used to describe any malfunction of the autonomic nervous system. There are many underlying diseases and conditions that can lead to dysfunction of the autonomic nervous system. This is not an all inclusive list, so check with your doctor if you believe you might have an underlying cause for your POTS or other form of dysautonomia. Remember that not every dysautonomia patient can find a specific underlying cause, and some of these conditions are very rare.