Hypophosphatemia

What Is Hypophosphatemia? 

Hypophosphatemia is when the body has low levels of phosphorus (also called phosphate). Phosphorus helps your muscles, nerves, and heart work properly and is important for building strong bones. Without enough phosphorus, bones can weaken and break more easily.

What Causes Hypophosphatemia?

Phosphorus comes from food and is absorbed in the digestive system, then processed by the kidneys. Problems in either system can lead to low phosphorus levels.

Common causes include:

• Digestive system issues: poor nutrition, vitamin D deficiency, chronic diarrhea, or conditions like inflammatory bowel disease that reduce absorption.
• Kidney problems: not reabsorbing enough phosphorus (renal tubulopathy) or losing too much phosphorus in urine (X-linked hypophosphatemia, hyperparathyroidism).
• Other medical conditions: refeeding syndrome, diabetic ketoacidosis, or severe infections (sepsis), which can move phosphorus into cells too quickly.
• Medications: some medicines can also lower phosphorus levels.

What Are the Signs & Symptoms of Hypophosphatemia?

Mild hypophosphatemia often has no symptoms. When symptoms do occur, they may include:

• Bowed legs or trouble walking
• Delayed walking
• Short height
• Problems with walking or gait
• Muscle pain or weakness
• Bone or joint pain
• Fatigue or tiredness
• Fractures (broken bones)

How Is Hypophosphatemia Diagnosed?

Your provider may order:

• Blood tests to check phosphorus and other markers like calcium, vitamin D, parathyroid hormone, alkaline phosphatase, and kidney function
• Genetic testing for inherited causes
• X-rays, bone density scans (DXA), or kidney ultrasounds

How Is Hypophosphatemia Treated?

The main goal is to raise phosphorus levels and treat the underlying cause. This may include:

• Phosphorus supplements by mouth or through an IV (intravenous) line
• Addressing the condition or problem that caused the low phosphorus

What Are the Long-Term Effects of Hypophosphatemia?

Long-term effects vary based on the cause but may include:

• Bone fractures
• Hearing loss
• Kidney damage

Severe untreated hypophosphatemia can lead to serious complications like coma or even death.