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The British Journal of Dermatology Mar 2020
Topics: Homeostasis; Humans; Keratoderma, Palmoplantar; Pachyonychia Congenita; Skin
PubMed: 31814103
DOI: 10.1111/bjd.18688 -
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 -
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 -
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 -
KERATIN 17-related recessive atypical pachyonychia congenita with variable hair and tooth anomalies.European Journal of Human Genetics :... Nov 2022We present the first pachyonychia congenita (PC) to involve all ectodermal derivatives and the first recessive KRT17-related PC in total seven members of two...
We present the first pachyonychia congenita (PC) to involve all ectodermal derivatives and the first recessive KRT17-related PC in total seven members of two consanguineous Pakistani families. This atypical PC is characterized by an unusual combination of pachyonychia, plantar keratoderma, folliculitis, alopecia, sparse eyebrows, dental anomalies and variable acanthosis nigricans of neck, dry skin, palmoplantar hyperhidrosis, recurrent blisters on soles and/or arms, rough sparse hair on scalp and keratosis pilaris. By exome sequencing we detected homozygous KRT17 c.281G>A (p.(Arg94His)) in affected individuals, and linkage mapping indicated a single locus. Heterozygous variants in KRT17 cause PC2 (PC-K17) with main characteristics of pachyonychia, subungual keratosis, palmoplantar keratoderma, hyperhidrosis, oral leukokeratosis and epidermal cysts, or steatocystoma multiplex, both with dominant inheritance. The causative variant has been reported in heterozygous state in a family afflicted with severe steatocystoma multiplex and in a sporadic PC2 case, and thus we also define a third phenotype related to the variant. Both exome sequencing and linkage mapping demonstrated recessive inheritance whereas Sanger sequencing indicated heterozygosity for the causal variant, reiterating caution for simple targeted sequencing for genetic testing. Testing parents for variants found in sibs could uncover recessive inheritance also in other KRT genes.
Topics: Humans; Eyebrows; Hyperhidrosis; Keratin-17; Mutation; Nails, Malformed; Pachyonychia Congenita; Steatocystoma Multiplex; Tooth Abnormalities; Pedigree
PubMed: 35676340
DOI: 10.1038/s41431-022-01128-4 -
Indian Journal of Dermatology,... 2023Background Plantar keratoderma is a common finding in pachyonychia congenita, significantly impairing ambulation and quality of life. Due to the variation of pain...
Background Plantar keratoderma is a common finding in pachyonychia congenita, significantly impairing ambulation and quality of life. Due to the variation of pain reporting in pachyonychia congenita clinical studies, it is difficult to evaluate the efficacy of treatment outcomes for painful plantar keratodermas. Objectives To objectively analyse associations between plantar pain and activity levels in pachyonychia congenita patients using a wristband tracker. Methods Pachyonychia congenita patients and matched normal controls wore wristband activity trackers and completed a daily digital survey to record their highest and total pain scores (0-10 scale) each day for 28 consecutive days during four different seasons. Results Twenty four participants (12 pachyonychia congenita patients and 12 matched normal controls) completed the study. Pachyonychia congenita patients walked 1801.30 fewer steps/day (95% CI, -3666.4, 64.1) than normal controls (P = 0.072) and had greater average total [5.26; SD, 2.10] and highest (6.92; SD, 2.35) daily pain than normal controls [0.11 (SD, 0.47), 0.30 (SD, 0.22), respectively] (P < 0.001, both). On average, for each one unit increase in daily highest pain level, pachyonychia congenita activity decreased 71.54 steps/day (SE, 38.90, P = 0.066). Limitation The study had a small number of participants, limiting statistical power. Only pachyonychia congenita patients, ages 18 years or older, with keratin 6a, keratin 16, and keratin 17 mutations were included, limiting generalizability. Conclusion Pachyonychia congenita patients were less active with significantly higher pain than normal controls. There was an inverse correlation between pain and activity. Our findings suggest that wristband tracker technology may be used to evaluate treatment efficacy in future trials on severe plantar pain; therapeutic interventions that decrease plantar pain should correlate with significant increases in activity using wristband trackers.
Topics: Humans; Pachyonychia Congenita; Quality of Life; Fitness Trackers; Shoes; Keratin-6; Pain; Mutation; Walking
PubMed: 37317732
DOI: 10.25259/IJDVL_939_2022 -
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