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Journal of Cosmetic Dermatology Dec 2019Pachyonychia congenita (PC), a rare autosomal dominant disorder, is featured by significant hypertrophic nail, palmoplantar keratoderma, and plantar pain. It is caused... (Review)
Review
BACKGROUND
Pachyonychia congenita (PC), a rare autosomal dominant disorder, is featured by significant hypertrophic nail, palmoplantar keratoderma, and plantar pain. It is caused by the mutation of KRT6A, KRT6B, KRT6C, KRT16, or KRT17.
AIMS
To identify the gene mutation caused the PC in a Chinese family.
PATIENTS/METHODS
Genomic DNA was extracted from peripheral blood samples of five patients and six healthy individuals. Genomic DNA of three patients was sequenced by whole-exome sequencing (WES). Then, exons 6 of KRT16 of all samples were amplified by polymerase chain reaction (PCR), and PCR products were sequenced to identify potential mutations.
RESULTS
We identified the proline substitution mutation p.Leu421Pro (c.1262T>C) in the 2B domain of K16 that is associated with PC in a Chinese family. The same mutation was not found in the six healthy individuals of the family.
CONCLUSIONS
The mutation found in this study is the first report in China. So far, 25 mutations in KRT16 have been reportedly associated with PC. Twenty-one mutations are located on exon 1, and four mutations on exon 6.
Topics: Asian People; Female; Humans; Keratin-16; Male; Middle Aged; Mutation; Pachyonychia Congenita; Pedigree
PubMed: 30859684
DOI: 10.1111/jocd.12905 -
Plastic and Reconstructive Surgery.... May 2017
PubMed: 28607853
DOI: 10.1097/GOX.0000000000001325 -
Indian Dermatology Online Journal 2023
PubMed: 37727554
DOI: 10.4103/idoj.idoj_533_22 -
The British Journal of Dermatology Mar 2020
Topics: Humans; Keratin-6; Mitochondria; Mutation; Pachyonychia Congenita
PubMed: 31571193
DOI: 10.1111/bjd.18465 -
The Journal of Investigative Dermatology Dec 2021Pachyonychia congenita (PC) is a genetic disorder of keratin that presents with nail dystrophy, painful palmoplantar keratoderma, and other clinical manifestations. We...
Pachyonychia congenita (PC) is a genetic disorder of keratin that presents with nail dystrophy, painful palmoplantar keratoderma, and other clinical manifestations. We investigated the genotype‒structurotype‒phenotype correlations seen with mutations in keratin genes (keratin [K]6A, K6B, K6C, K16, K17) and utilized protein structure modeling of high-frequency mutations to examine the functional importance of keratin structural domains in PC pathogenesis. Participants of the International PC Research Registry underwent genetic testing and completed a standardized survey on their symptoms. Our results support previous reports associating oral leukokeratosis with K6A mutations and cutaneous cysts, follicular hyperkeratosis, and natal teeth with K17 mutations. Painful keratoderma was prominent with K6A and K16 mutations. Nail involvement was most common in patients with K6A mutation and least common in those with K6C mutation. Across keratin subtypes, patients with coil 2B mutations had the greatest impairment in ambulation, and patients with coil 1A mutations reported more emotional issues. Molecular modeling demonstrated that hotspot missense mutations in PC largely disrupted hydrophobic interactions or surface charge. The former may destabilize keratin dimers/tetramers, whereas the latter likely interferes with higher-order keratin filament formation. Understanding the pathologic alterations in keratin structure improves our knowledge of how PC genotype correlates with clinical phenotype, advancing insight into disease pathogenesis and therapeutic development.
Topics: Genetic Association Studies; Humans; Keratin-16; Keratin-17; Keratin-6; Keratins; Models, Molecular; Mutation; Pachyonychia Congenita
PubMed: 34116063
DOI: 10.1016/j.jid.2021.03.035 -
Pediatric Dermatology Mar 2023Patient and caregiver perspectives are critical in understanding dermatologic disease impact, presentation, and management in children. The Pediatric Dermatology...
BACKGROUND/OBJECTIVES
Patient and caregiver perspectives are critical in understanding dermatologic disease impact, presentation, and management in children. The Pediatric Dermatology Research Alliance (PeDRA) Patient Advisory Committee (PtAC), a group of patient representatives and parents of children with cutaneous disease, pursued a multistep, iterative, consensus-building process to identify comprehensive, high-priority research needs.
METHODS
Building on discussions at the 2020 PeDRA Annual Conference, a research prioritization survey was developed and completed by PtAC members. Survey themes were aggregated and workshopped by the PtAC through a series of facilitated calls. Emerging priorities were refined in collaboration with additional PeDRA patient community members at the 2021 PeDRA Annual Conference. Subsequently, a final actionable list was agreed upon.
RESULTS
Fourteen PtAC members (86.7% female) representing patients with alopecia areata, atopic dermatitis, vascular birthmarks, congenital melanocytic nevi, ectodermal dysplasias, epidermolysis bullosa, Gorlin syndrome, hidradenitis suppurativa, ichthyosis, pemphigus, psoriasis, Sturge-Weber syndrome, and pachyonychia congenita completed the survey. Following serial PtAC meetings, 60 research needs were identified from five domains: psychosocial challenges, health care navigation/disease management, causes/triggers, treatments to preserve or save life, and treatments to preserve or save quality of life.
CONCLUSIONS
Many pediatric dermatology research priorities align across affected communities and may drive meaningful, patient-centric initiatives and investigations.
Topics: Child; Humans; Female; Male; Dermatology; Quality of Life; Alopecia Areata; Research; Patient-Centered Care
PubMed: 36443263
DOI: 10.1111/pde.15199 -
Skin Appendage Disorders Apr 2021Pachyonychia congenita (PC) is a rare dermatosis that confers lifelong physical and emotional morbidities in affected patients. However, the clinical findings,...
INTRODUCTION
Pachyonychia congenita (PC) is a rare dermatosis that confers lifelong physical and emotional morbidities in affected patients. However, the clinical findings, treatments, and psychosocial impact of this disease have not been adequately described. The International PC Research Registry (IPCRR), a multinational initiative to collect data on PC patients, has allowed an opportunity to distinguish the salient features of this disease. We aimed to characterize the breadth and extent of nail disease, treatments, and quality of life in PC patients, and to describe any significant differences in clinical presentation or treatment of PC subtypes.
METHODS
The most recent IPCRR patient survey data consisting of an 857-response questionnaire and a 102-response addendum were analyzed in a retrospective analysis. The survey data were collected as part of a multinational, multicenter initiative and comprise the largest representative population of PC to date. Participants (survey respondents) were included in the study based on questionnaire responses and a genetic confirmation of having a PC subtype.
RESULTS
A total of 857 survey responses were collected. Genetic variations among PC subtypes influence nail disease onset and severity of symptoms. Nail disease negatively impacts patients' emotional health, especially during the adolescent and young adult years. Nail treatment tools vary little in terms of effectiveness and acquired infection rates.
CONCLUSION AND DISCUSSION
Patients with different PC subtypes have distinct clinical nail presentations and psychosocial impact. Genetic testing should be used to confirm PC diagnoses. Further characterization of PC, especially the rarer subtypes, may allow for more individualized patient education.
PubMed: 34055907
DOI: 10.1159/000513340 -
The Journal of Laryngology and Otology Jul 2017Pachyonychia congenita is a rare keratinising disorder, which typically presents during the first three years of life and usually affects the nails and palmoplantar... (Review)
Review
BACKGROUND
Pachyonychia congenita is a rare keratinising disorder, which typically presents during the first three years of life and usually affects the nails and palmoplantar surfaces. It can involve the larynx and potentially result in life-threatening airway obstruction.
METHODS
A case report is presented and the findings of a literature review are reported. The review involved a PubMed search using the keywords 'pachyonychia congenita' together with 'larynx', 'laryngeal involvement', 'laryngeal obstruction', 'airway obstruction', 'hoarseness' and/or 'stridor'.
RESULTS
A five-year-old boy, with confirmed pachyonychia congenita, presented with complications of laryngeal involvement over a four-year period. He required three intubations and a tracheostomy for acute airway obstruction. Treatment with potassium titanyl phosphate laser laryngoscopy stabilised the progression of laryngeal disease.
CONCLUSION
Patients with pachyonychia congenita and laryngeal involvement can have a varied presentation, ranging from hoarseness to acute airway obstruction. Management can be a challenge, requiring early evaluation, regular surveillance and aggressive treatment. This paper reports our experience in managing and treating the laryngeal complications of a child with pachyonychia congenita.
Topics: Airway Obstruction; Child, Preschool; Congenital Abnormalities; Dyspnea; Humans; Laryngeal Diseases; Laryngoscopy; Larynx; Male; Pachyonychia Congenita; Respiratory Sounds
PubMed: 27762179
DOI: 10.1017/S0022215116008264 -
Cureus Sep 2023Background and objective Nail disorders encompass a wide spectrum of conditions, spanning congenital, developmental, infectious, neoplastic, degenerative,...
Background and objective Nail disorders encompass a wide spectrum of conditions, spanning congenital, developmental, infectious, neoplastic, degenerative, dermatological, and systemic diseases. A comprehensive exploration of their clinical manifestations, incidence, and associations is crucial for precise diagnosis and effective management. Methods This observational cross-sectional study conducted at B.J. Medical College and Civil Hospital, Ahmedabad involved 300 consecutive patients with nail changes from July 2017 to June 2019 reporting diverse dermatological and systemic conditions. The inclusion criteria involved patients of both genders and all age groups displaying nail changes associated with dermatological and systemic diseases. Data collection entailed a comprehensive clinical history, systemic and dermatological examinations, nail assessment using Dermoscope (DermLite 3, 10x), and supplementary tests. Analyses were performed on Microsoft Excel 2007 software. The study was approved by the Institute Ethics Committee. Results Among the 300 cases, females had a higher prevalence of nail involvement (57%), with a female-to-male ratio of 1.3:1. The most affected age group was 21-40 years, with 6-10 nails typically affected. Notably, housewives showed a higher prevalence. The most frequent nail condition was onychomycosis (24.33%) followed by psoriatic nail changes (20%). Less frequent nail changes involved eczema (5.7%), paronychia (5%), drug-induced (4.3%), lichen planus (3.7%), trauma-induced (3%), twenty nail dystrophy (2.33%), Darier's disease (2%), pemphigus vulgaris (2%), alopecia areata (1.67%), median Heller dystrophy (1.33%), atopic dermatitis (1%), epidermolysis bullosa (1%), racquet nail (1%), leprosy (1%), pityriasis rubra pilaris (0.67%), vitiligo (0.67%), secondary syphilis (0.67%), pachyonychia congenita (0.67%), as well as a case each of total leukonychia, subungual warts, Koenen tumor, and periungual fibroma(0.33%). Systemic autoimmune connective tissue disorders (CTD) accounted for 9%; the most common nail finding observed was nail fold erythema (48.1%) followed by nail fold telangiectasis (44.4%). In systemic sclerosis (SS), the most common finding was nail fold telangiectasia, and in systemic lupus erythematosus (SLE), the most common was nail fold erythema. Scleroderma capillary pattern on nail fold capillaroscopy was found in seven patients with SS, two patients with dermatomyositis, and only one patient with SLE. Nail changes observed in systemic diseases include onychomycosis in diabetes mellitus and chronic renal failure patients, splinter hemorrhages in ischemic heart disease and hypertension, longitudinal melanonychia in HIV, and koilonychia and platynychia in iron deficiency anemia. Other systemic diseases, such as Addison's disease and renal failure, also exhibited various nail changes. Conclusions Beyond their cosmetic importance, nails hold a vital pathologic role. Proficiency in nail terminology and classification is key for skillful evaluation. Understanding normal and abnormal nail variants, along with their disease associations, benefits diagnosis and tailored management. Nails, often overlooked but accessible, serve as a window into patients' general health and should be an integral part of thorough examinations. This study highlights an intricate clinical panorama of nail disorders, highlighting their significant role in both dermatological and systemic contexts.
PubMed: 37701161
DOI: 10.7759/cureus.45007 -
The British Journal of Dermatology Mar 2020Pachyonychia congenita (PC) is a group of autosomal dominant disorders caused by mutations in one of five keratin genes (KRT6A, KRT6B, KRT6C, KRT16, KRT17). The...
BACKGROUND
Pachyonychia congenita (PC) is a group of autosomal dominant disorders caused by mutations in one of five keratin genes (KRT6A, KRT6B, KRT6C, KRT16, KRT17). The establishment of an international registry containing clinical and molecular data led to the development of a disease classification based on the mutant gene and associated features.
OBJECTIVES
To harness the same resource to clarify the prevalence of PC-associated clinical features, delineate phenotype-genotype correlations and identify prognostic features for disease severity.
METHODS
In total, 815 individuals with confirmed keratin mutations registered in the International Pachyonychia Congenita Research Registry were surveyed for clinical findings associated with PC. Data were analysed using various statistical methods, including the Student's t-test, χ -test and anova tests for differences in means/proportions. Spearman correlation and logistic regression were used for phenotype-genotype correlations.
RESULTS
KRT6A mutations were associated with oral leucokeratosis, hoarseness, youngest age or highest number of fingernails/toenails involved, and use of walking aids. KRT17 mutations were most commonly associated with cysts and natal teeth. Using logistic regression, we found that oral leucokeratosis was correlated with earlier toenail involvement, walking aids, nursing difficulties and hoarseness. Cysts were correlated with oral leucokeratosis, natal teeth and ear wax. Natal teeth predicted earlier toenail involvement, walking difficulties and cyst formation. Hoarseness was correlated with an increased number of involved fingernails.
CONCLUSIONS
Here, we establish phenotype-genotype correlations in the largest cohort of patients with PC described to date and reveal novel and clinically useful predictors of disease course and manifestations. What's already known about this topic? Pachyonychia congenita (PC) is a group of autosomal dominant disorders caused by mutations in one of five keratin genes (KRT6A, KRT6B, KRT6C, KRT16, KRT17). The main clinical features are nail dystrophy, palmoplantar keratoderma, oral leucokeratosis and cysts. The establishment of an international registry containing the clinical and molecular data of patients with PC led to the development of a disease classification based on the mutant gene and associated features. What does this study add? Data were collected via an international registry to clarify the prevalence of PC-associated clinical features, delineate phenotype-genotype correlations and identify prognostic features for disease severity. This is the largest cohort of patients with PC described to date. The earliest clinical manifestations of PC are nail dystrophy and palmoplantar keratoderma. Diagnosis can be suspected and confirmed in preschool years. Painful plantar keratoderma has the most profound and debilitating effect on quality of life and daily function. Linked Editorial: Steele and O'Toole. Br J Dermatol 2020; 182:521-522. Linked Comment: Mordaunt. Br J Dermatol 2020; 182:537.
Topics: Child, Preschool; Cohort Studies; Humans; Keratin-6; Keratoderma, Palmoplantar; Mutation; Pachyonychia Congenita; Quality of Life
PubMed: 31823354
DOI: 10.1111/bjd.18794