Primary hypertrophic osteoarthropathy (PHO), also known as pachydermoperiostosis, is a rare genetic disorder that affects the bones, skin, and other tissues in the body. It is characterized by abnormal thickening of the skin, enlargement of the extremities, and bone changes.
The primary feature of PHO is the presence of pachydermia, which refers to the thickening of the skin, especially on the face and scalp. This thickened skin gives a coarse and wrinkled appearance, similar to the skin of an elephant. Additionally, patients may experience excessive sweating and oiliness of the skin.
Enlargement of the extremities, including the fingers, toes, and sometimes the nose and ears, is another hallmark of PHO. This enlargement is caused by a buildup of soft tissue and fluid in these areas.
Bone changes associated with PHO include thickening and enlargement of the long bones in the arms and legs. This can result in pain, stiffness, and limited mobility. Joint abnormalities, such as arthritic changes, may also be present.
PHO is caused by mutations in specific genes involved in bone and connective tissue development. It is usually inherited in an autosomal dominant pattern, meaning that a person with one affected parent has a 50% chance of inheriting the condition.
While there is no cure for PHO, treatment focuses on managing the symptoms and improving quality of life. This may include physical therapy, pain management, and the use of medications to reduce inflammation and control symptoms. Additionally, regular monitoring by a healthcare professional is necessary to ensure early detection and management of any complications.
