Why is it that POTS patients go to health care providers complaining of a multitude of unexplainable symptoms such as headaches, fatigue, lightheadedness, “brain fog,” rapid heart, blurry vision and abdominal pain without their POTS being suspected? Misdiagnosis and delay is so typical for POTS. In fact, Dysautonomia International reports that the average delay in establishing a POTS diagnosis is almost 6 years. One important reason is that performance of routine physical examinations and routine screening laboratory tests always fail to provide clues as to the responsible diagnosis, POTS. Yes, the special HUTT (Head-Up Tilt Test) that reveals the onset of rapid heart rate upon assuming the upright posture would be helpful, but it is not thought of or readily available.
However, there are subtle skin signs, frequently overlooked, that are important clues to the presence of POTS. The most consistent and almost diagnostic physical sign of POTS is observed in the lower extremities. Associated with the excessive pooling of venous blood in the lower extremities is a bluish-purple discoloration of the legs below the knees. This discoloration can be seen best following standing for a few minutes. This clue, leg discoloration, goes by the name of acrocyanosis (extremity blueness). This bluish-purple pooling discoloration in the legs is usually bilateral, symmetrical and generalized. But, it can also be blotchy and spotty. Congestion within the veins causes the lower legs to feel cool and moist to touch. When the venous stretching has been chronic, swelling of the feet can occur. POTS patients do not report experiencing this bluish-purple discoloration clue of their legs. When looked for, this diagnostic clue can often be discovered after standing.
Additional skin symptoms provide evidence of autonomic nervous system dysfunction in POTS patients. POTS patients frequently report experiencing flushing and sweating of the neck, upper chest and arms. Others report “Raynaud’s phenomenon,” the tips of fingers turning white with associated pain when exposed to the cold. Generally this paleness clears when the hands are warmed. These latter clues occur in many other disorders and are not as diagnostic of POTS as is the bilateral, bluish-purple pooling discoloration clue in the legs.