Pachyonychia Congenita (PC)
Description
Pachyonychia Congenita (PC) is a rare, inherited disorder that primarily affects the nails, skin, and mucous membranes. It‘s characterized by thick, abnormally shaped nails, along with other symptoms like skin lesions, palmoplantar keratoderma (thickened skin on palms and soles), and oral mucosal changes. This article delves into the complexities of PC, exploring its causes, symptoms, diagnosis, and management strategies.
Genes Involved
Genes Involved:
PC is caused by mutations in several genes, including:
- KRT6A, KRT6B, KRT16: These genes code for keratins, proteins that form the structural framework of skin, nails, and hair.
- KRT6C, KRT17: These genes also code for keratins involved in the formation of skin and nails.
- GJB3: This gene codes for a protein that helps connect cells in the skin.
Recognizing the Signs and Symptoms
Recognizing the Signs and Symptoms:
- Nail Abnormalities: The hallmark of PC is thick, abnormally shaped nails that are often brittle and prone to splitting. The nails can also be discolored, with a yellowish or brownish hue.
- Palmoplantar Keratoderma: Thickened skin on the palms and soles is another common symptom. This can cause discomfort and make walking difficult.
- Oral Mucosal Changes: Lesions and white patches may appear inside the mouth, leading to pain and difficulty eating.
- Skin Lesions: PC can cause various skin lesions, including hyperkeratosis (thickening of the skin), follicular keratosis (bumps around hair follicles), and cysts.
- Hair Abnormalities: In some cases, hair can be brittle or grow abnormally.
- Other Symptoms: Pain, itching, and discomfort are common associated symptoms. The severity of symptoms can vary greatly among individuals.
Causes
Causes:
PC is an autosomal dominant disorder, meaning that a person needs only one copy of the mutated gene from either parent to inherit the condition. If one parent has PC, there is a 50% chance that their child will inherit the disorder.
Inheritance/recurrence risk
Inheritance or Recurrence Risk:
PC is an autosomal dominant condition. This means a person needs only one copy of the mutated gene from either parent to inherit the disorder.
- If one parent has PC, there is a 50% chance that their child will inherit the condition.
- If both parents have PC, there is a 75% chance their child will inherit the condition.
- If neither parent has PC, there is a very low chance their child will inherit the condition, but there may be instances of a spontaneous mutation.
