1-  hydroxylation defect in postural orthostatic tachycardia syndrome: remission with calcitriol supplementation

Abstract

A 37-year-old woman presented with a history of reactive hypoglycaemia, non-classic adrenal hyperplasia (NCAH), osteopenia and fibromyalgia. After several months of palpitations, postural orthostatic tachycardia syndrome (POTS) was diagnosed by tilt table studies. Her heart rate (HR) reached 191 bpm at 60 degrees from horizontal. Investigation suggested increase in epinephrine and norepinephrine levels in response to tilt table. Her 25(OH) vitamin D level measured by immunoextraction radioimmunoassay was 35 pg/ ml (normal 9-54 pg/ml) while her 1,25(OH)(2) vitamin D3 level was 24 pg/ml (normal 30-67 pg/ml). Accordingly, she was started on calcitriol 0.25 mcg orally daily. At her next visit after 5 months, she reported remarkable improvement in her palpitations and had been working full time for the past 4 months. HR both seated and upright was 72 bpm. After 3 months, her 1,25(OH)(2) vitamin D3 level on calcitriol was 40 pg/ml. The authors suggest that 1-α hydroxylation defects should be sought and treated, if present, with calcitriol in patients with POTS.

When POTS is the tip of the iceberg: Rare cases of dysautonomia as a possible manifestation of another disorder

“…Additionally, treatment of the underlying and comorbid conditions, if discovered, may significantly improve or completely resolve the autonomic disorder as it is sometimes observed in patients with POTS associated with vitamin deficiencies and autoimmune disorders. 10–13 In this case series, a search for an underlying disorder revealed rare or unexpected diseases that would’ve been missed if the diagnostic investigation ended with the diagnosis of POTS and neurogenic orthostatic hypotension. Furthermore, autonomic dysfunction completely resolved in the case of Fabry disease and carcinoid tumor and improved significantly in the patient with Hodgkin’s lymphoma when these disorders were treated with targeted therapy.…”

Effects of Vitamin D Deficiency on the Function of the Cardiac Autonomic Nervous System in Rats

“…Currently, a large number of studies have shown an important association between VD deficiency and ANS activity. For example, Chaudhari et al found that patients with postural standing tachycardia syndrome had lower levels of ossified triol (1,25(OH)D 3 ) than normal subjects and that appropriate supplementation improved patient symptoms, revealing that VD inhibits autonomic nervous system dysfunction in the body [ 13 ]. A clinical study reported that cardiac autonomic function was impaired in people with VD deficiency despite the absence of overt cardiac involvement and symptoms [ 14 ].…”