Riley – Day Syndrome, also known as familial dysautonomia, is an inherited disorder that affects autonomous nervous system of the body resulting in multisystem dysfunction. The symptoms of this condition however show when the related gene is passed on to the child by both the parents. The syndrome is named after American pediatricians Conrad Milton Riley and Richard Lawrence Day, who first described it in 1949.
The syndrome is strikingly characterized by lack of tears with emotional crying. In response to emotional stress or pain, patients rather experience episodic hypertension but no tears. Some other signs like decreased perception of pain and temperature changes and excessive sweating and blotchiness of the skin during excitement and eating are also associated with it.
Since body functions controlled by autonomous nervous system—blood pressure, heart rate, sweating, bowel and bladder emptying, digestion, and the senses, are affected, breath-holding spells, vomiting, constipation, reduced sense of taste, diarrhea, and feeding problems appear as other symptoms.