Hypophosphatemia, or phosphate deficiency, is a condition in which phosphate levels drop to a point which may become dangerous. Phosphate is an essential mineral which is required by many cellular processes, and hypophosphatemia can cause severe health problems. There are several mechanisms which can cause phosphate deficiency, and several health conditions of which this deficiency is a feature.
Phosphate is one of the most widely-used minerals that the body requires. Most of the body’s phosphate is stored in bones, and is part of the mineral matrix which is secreted and maintained by bone cells. Phosphate is an essential component of DNA and other nucleic acids, and is a key component of ATP, the molecule which is essential for almost all cellular processes which use energy.
The requirement of phosphate for these key cellular functions means that acute or chronic deficiency can have serious consequences. The most common cause of hypophosphatemia is increased phosphate excretion. This means that phosphate is excreted in feces or urine instead of being used in the body. Increased phosphate excretion may be caused by a range of metabolic deficiencies, many of which are inherited.
Inadequate dietary intake of phosphate is not a common cause of deficiency, because almost all foods contain phosphate. A generally poor diet low in nutrients such as Vitamin D, which facilitates phosphate uptake by cells, can exacerbate a pre-existing chronic phosphate deficiency, however. Overuse of certain types of antacids can cause hypophosphatemia, particularly those which contain aluminum, magnesium, or calcium.
The type of hypophosphatemia symptoms that may develop in a given individual depend on the cause of the phosphate deficiency, and its duration. Most cases of mild or short-term deficiency do not cause any symptoms, as the body is able to compensate for the lack of phosphate on a short-term basis. The most problematic symptom for people with chronic disease caused by phosphate deficiency is bone wastage which causes bone pain, brittle bones, and a greatly increased risk of fractures.
Children who are chronically deficient in phosphate are also at risk of kidney disease and hyperparathyroidism. This condition is a parathyroid gland dysfunction which can cause symptoms such as fatigue, depression, pain, and nausea. Children may also develop hypophosphatemic rickets, which causes the legs to become severely bowed. Most cases of chronic childhood phosphate deficiency are caused by a hereditary metabolic disorder.
Treatment for chronic phosphate deficiency is administered based on the cause of the deficiency. In situations where the problem is caused by a reduced ability to absorb dietary phosphate, such as in severe vitamin D deficiency, the underlying cause is treated in addition to providing supplemental phosphate. People with metabolic disorders that reduce phosphate metabolism can typically manage the problem with high-phosphate diets and vitamin D supplements.
Acute hypophosphatemia can cause a range of potentially dangerous symptoms. Phosphate deficiency can cause cardiac symptoms including low blood pressure, and increased risk of dangerous arrhythmia. Acute deficiency can also cause neurological symptoms such as confusion and other cognitive disturbances, paralysis, seizures, or coma. This type of phosphate deficiency is commonly treated with oral or intravenous phosphate-containing preparations.