Question: What is (are) Pachyonychia congenita ?
Answer: Pachyonychia congenita (PC) is a rare inherited condition that primarily affects the nails and skin. The fingernails and toenails may be thickened and abnormally shaped. Affected people can also develop painful calluses and blisters on the soles of their feet and less frequently on the palms of their hands (palmoplantar keratoderma). Additional features include white patches on the tongue and inside of the mouth (leukokeratosis); bumps around the elbows, knees, and waistline (follicular hyperkeratosis); and cysts of various types including steatocystoma. Features may vary among affected people depending on their specific mutation. PC is divided into 5 types based on the specific keratin gene involved: PC-K6a, PC-K6b, PC-K6c, PC-K16, and PC-K17. All forms are inherited in an autosomal dominant manner. Treatment is based on the signs and symptoms present in each person.
Source: GARD

Question: What are the symptoms of Pachyonychia congenita ?
Answer: What are the signs and symptoms of Pachyonychia congenita? The signs and symptoms of pachyonychia congenita (PC) vary based on the specific keratin gene involved (KRT6A, KRT6B, KRT6C, KRT16, and KRT17) and the specific gene mutation. However, the most common features of the condition include: Thickened nails Plantar hyperkeratosis (thickened skin on the soles of the feet) with underlying blisters Plantar pain Various types of cysts (i.e. steatocystoma and pilosebaceous cysts - two types of sebaceous gland cysts) Follicular hyperkeratosis (small bumps at the base of hairs) Leukokeratosis (white patches on the tongue, in the mouth, or on the inside of the cheek) Some affected people may also develop calluses on the palms of the hands (palmar hyperkeratosis), sores at the corner of the mouth; natal teeth; a hoarse cry or voice caused by white film on the larynx (voice box); and/or intense pain when beginning to eat or swallow. For more specific information on the signs and symptoms of PC, including specific features that are not associated with the condition, please visit the Pachyonychia Congenita Project's Web site. The Human Phenotype Ontology provides the following list of signs and symptoms for Pachyonychia congenita. If the information is available, the table below includes how often the symptom is seen in people with this condition. You can use the MedlinePlus Medical Dictionary to look up the definitions for these medical terms. Signs and Symptoms Approximate number of patients (when available) Abnormality of nail color 90% Abnormality of the fingernails 90% Abnormality of the toenails 90% Hyperhidrosis 90% Abnormal blistering of the skin 50% Anonychia 50% Carious teeth 50% Ichthyosis 50% Neoplasm of the skin 50% Alopecia 7.5% Cataract 7.5% Cognitive impairment 7.5% Corneal dystrophy 7.5% Hepatomegaly 7.5% Laryngomalacia 7.5% Respiratory insufficiency 7.5% Autosomal dominant inheritance - Chapped lip - Dry hair - Epidermoid cyst - Follicular hyperkeratosis - Furrowed tongue - Gingivitis - Heterogeneous - Hoarse voice - Nail dysplasia - Nail dystrophy - Natal tooth - Onychogryposis of toenails - Oral leukoplakia - Palmar hyperkeratosis - Palmoplantar hyperhidrosis - Palmoplantar hyperkeratosis - Palmoplantar keratoderma - Plantar hyperkeratosis - Sparse eyebrow - Sparse scalp hair - Steatocystoma multiplex - Subungual hyperkeratosis - Thick nail - The Human Phenotype Ontology (HPO) has collected information on how often a sign or symptom occurs in a condition. Much of this information comes from Orphanet, a European rare disease database. The frequency of a sign or symptom is usually listed as a rough estimate of the percentage of patients who have that feature. The frequency may also be listed as a fraction. The first number of the fraction is how many people had the symptom, and the second number is the total number of people who were examined in one study. For example, a frequency of 25/25 means that in a study of 25 people all patients were found to have that symptom. Because these frequencies are based on a specific study, the fractions may be different if another group of patients are examined. Sometimes, no information on frequency is available. In these cases, the sign or symptom may be rare or common.
Source: GARD

Question: What causes Pachyonychia congenita ?
Answer: What causes pachyonychia congenita? Pachyonychia congenita (PC) is caused by changes (mutations) in one of five genes: KRT6A, KRT6B, KRT6C, KRT16, and KRT17. These genes provide instructions for making a protein called keratin, which is found in the skin, hair, and nails. Mutations in any of these genes alter the structure of keratin proteins which interferes with their ability to provide strength and resilience to various parts of the body. This leads to the many signs and symptoms associated with pachyonychia congenita. PC is divided into 5 types based on the specific keratin gene involved: PC-K6a, PC-K6b, PC-K6c, PC-K16, and PC-K17.
Source: GARD

Question: Is Pachyonychia congenita inherited ?
Answer: How is pachyonychia congenita inherited? Pachyonychia congenita (PC) is inherited in an autosomal dominant manner. This means that to be affected, a person only needs a change (mutation) in one copy of the responsible gene in each cell. In some cases, an affected person inherits the mutation from an affected parent. Other cases may result from new (de novo) mutations in the gene. These cases occur in people with no history of the disorder in their family. A person with PC has a 50% chance with each pregnancy of passing along the altered gene to his or her child.
Source: GARD

Question: How to diagnose Pachyonychia congenita ?
Answer: Is genetic testing available for pachyonychia congenita? Yes, genetic testing is available for the five genes known to cause pachyonychia congenita. Carrier testing for at-risk relatives and prenatal testing are possible if the disease-causing mutation in the family is known. The Genetic Testing Registry (GTR) is a centralized online resource for information about genetic tests. The intended audience for the GTR is health care providers and researchers. Patients and consumers with specific questions about a genetic test should contact a health care provider or a genetics professional. How is pachyonychia congenita diagnosed? A diagnosis of pachyonychia congenita (PC) is often suspected based on the presence of characteristic signs and symptoms. In fact, one study found that approximately 97% of people with genetically confirmed PC have toenail thickening, plantar keratoderma (thickening of the skin on the soles of the feet) and plantar pain by age ten. Identification of a change (mutation) in one of the five genes associated with PC confirms the diagnosis.
Source: GARD

Question: What are the treatments for Pachyonychia congenita ?
Answer: How might pachyonychia congenita be treated? There is no cure for pachyonychia congenita (PC). Current management is focused on relief of pain and other symptoms; hygienic grooming practices (such as trimming the nails and calluses); and treatment of infections when necessary. Some affected people may also require aids to help with mobility, such as wheelchairs, crutches and/or canes. Pachyonychia Congenita Project offers more detailed information regarding the treatment and management of PC. Please click on the link to access this resource.
Source: GARD