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Primary Hyperparathyroidism

What is Primary Hyperparathyroidism?

Hyperparathyroidism is a condition that raises calcium levels in the blood. Once the calcium levels are above a certain threshold (usually about 2.7 mmol/L) the condition is known as hypercalcemia. The abnormally high calcium levels are caused by the overactive secretion of parathyroid hormone (PTH), which in turn is usually caused by a non-cancerous tumor (adenoma) in one or more of the small endocrine glands (parathyroid glands) of the neck.

Primary hyperparathyroidism is genetic, but not hereditary, in the sense that it is caused by the mutation in the parathyroid glands after birth. The condition has been found to be more prevalent in areas with high radioactivity, such as in the contamination zone around the Chernobyl nuclear power plant. This is thought to be caused by dangerously high strontium levels in the atmosphere.

Symptoms of Primary Hyperparathyroidism

It is more likely to affect women than men and the symptoms vary considerably and include:

Primary hyperparathyroidism is detected via blood tests or calcium infusions for more accurate results.


The most common treatment is to remove the affected gland entirely via surgery. Patients with mild forms of the disease sometimes respond to hormone therapy, and there are some newly released medications that are able to limit the secretion rate of the parathyroid glands.

The main bone-related conditions associated with primary hyperparathyroidism are osteomalacia and osteitis fibrosa cystica. Osteomalacia is the term generally applied to rickets when affecting adults and has the same pathology (http://www.learnbones.com/rickets-disease-in-children).

Osteitis fibrosa cystica affects the skeletal structure by increasing the rate at which bone cells are broken down, causing reduced bone density and increased likelihood of fracture. The breakdown of bone is caused by cells known as osteoclasts, which are programmed to remove living bone cells. Once Bone Disease exceeds the rate at which new bone cells are created the bone begins to degenerate.

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Test Your Knowledge

How Many Bones in the Human Body?

An adult has a total of 206 bones in their skeleton

How many Bones in a Child's Body?

A newborn baby has 270 bones in the skeletal system. Most of their skeleton is made up of cartilage which forms bone as it hardens over time. The bones in a child's skeleton fuse together as they grow, reducing the number, up until about 25 years old.

What is The Strongest Bone in the Human Body?

The femur or thigh bone is the strongest bone in the body. It is situated between the pelvis and the knee. It is also the longest bone in the body and is fully one quarter of your bodies' height.

What is the Weakest Bone in The Body?

The weakest bones in your body are the tiny bones inside your ear that enable you to hear. On the other hand; the most commonly fractured bone is the clavicle.

What is the Hardest Bone in the Body?

The hardest bone in the body is the petrous portion of the temporal bone. The temporal bones are found at the sides and base of the skull and the petrous portion is specifically the part at the base of the skull that contains the organs for hearing.

Where are the Smallest bones in Your Body Located?

The smallest bone in the body is called the stapes. It is a stirrup shaped bone found inside the ear drum that transmits vibrations enabling us to hear.

How many Bones are in the Leg?

A human leg contains 30 bones. There are 26 bones that make up the foot, and the four major bones of the leg, which are the thigh bone (femur), the shin bone (tibia), the calf bone (fibula) and the knee cap (patella)