A recurrent KCNK4 variant in a dominant pedigree with hypertrichosis and gingival fibromatosis syndrome: Variable phenotypic expressivity and insights on patients' dental management.

Abnormal hyperpolarization of the KCNK4 gene, expressed in the nervous system, brain, and periodontal ligament fibroblasts, leads to impaired neurotransmitter sensitivity, cardiac arrhythmias, and endocrine dysfunction, as well as, progressive cell proliferation. De novo gain of function variants in the KCNK4 gene were reported to cause a recognizable syndrome characterized by facial dysmorphism, hypertrichosis, epilepsy, intellectual/developmental delay, and gingival overgrowth (FHEIG, OMIM# 618381). FHEIG is extremely rare with only three reported cases in the literature. Herein, we describe the first inherited KCNK4 variant (c.730G>C, p.Ala244Pro) in an Egyptian boy and his mother. Variable phenotypic expressivity was noted as the patient presented with the full-blown picture of the syndrome while the mother presented only with hypertrichosis and gingival overgrowth without any neurological manifestations. The c.730G>C (p.Ala244Pro) variant was described before in a single patient and when comparing the phenotype with our patient, a phenotype-genotype correlation seems likely. Atrial fibrillation and joint laxity are new associated findings noted in our patient extending the clinical phenotype of the syndrome. Dental management was offered to the affected boy and a dramatic improvement was noted as the patient regained his smile, restored the mastication function, and resumed his psychological stability.

Diffuse neurofibroma with hypertrichosis in a toddler.

Diffuse neurofibroma is a rare type of neurofibroma uncommonly reported in infancy. It is a slow growing tumor originating in the peripheral nerve sheath. We present the case of a 17-month-old boy with diffuse neurofibroma of the scalp associated with hypertrichosis. His genetic and clinical workup for neurofibromatosis was negative.

Patients with DeSanto-Shinawi syndrome: Further extension of phenotype from Italy.

Here we describe three patients with neurodevelopmental disorders characterized by mild-to-moderate intellectual disability, mildly dysmorphic features, and hirsutism, all of which carry de novo sequence variants in the WW domain-containing adaptor of the coiled-coil (WAC) gene; two of these-c.167delA, p.(Asn56I1efs*136) and c.1746G>C, p.(Gln582His)-are novel pathogenic variants, and the third-c.1837C>T, p(Arg613*)-has been previously described. Diseases associated with WAC include DeSanto-Shinawi syndrome; to date, de novo heterozygous constitutional pathogenic WAC variants have caused a syndromic form of intellectual disability and mild dysmorphic features in 33 patients, yet potential associations with other clinical manifestations, such as oligomenorrhea and hyperandrogenism, remain unknown, because the phenotypic spectrum of the condition has not yet been delineated. The patient bearing the novel c.167delA WAC gene variant presented a normal psychomotor development, oligomenorrhea, hyperandrogenism, and hirsutism, and hirsutism was also observed in the patient with the c.1746G>C WAC gene variant. Hypertrichosis and hirsutism have been described in nine DeSanto-Shinawi patients, only in 17 of the 33 aforementioned patients thus far reported this aspect, and no hormonal-pattern data are available. In conclusion, we note that the pathogenic c.167delA WAC variant may be associated with a mild phenotype; and in addition to the neurodevelopmental problems nearly all DeSanto-Shinawi patients experience (i.e., intellectual disability and/or developmental delay), we recommend the addition of mild dysmorphic features, hirsutism, and hypertrichosis to this clinical presentation.

Multiple vascular anomalies and refractory pericardial effusion in a young patient with Cantu syndrome: a case report and review of the literature.

BACKGROUND: Cantu syndrome is a rare and complex multisystem disorder characterized by hypertrichosis, facial dysmorphism, osteochondroplasia and cardiac abnormalities. With only 150 cases reported worldwide, Cantu syndrome is now gaining wider recognition due to molecular testing and a growing body of literature that further characterizes the syndrome and some of its most important features. Cardiovascular pathology previously described in the literature include cardiomegaly, pericardial effusion, vascular dilation and tortuosity, and other congenital heart defects. However, cardiovascular involvement is highly variable amongst individuals with Cantu syndrome. In some instances, it can be extensive and severe requiring surgical management and long term follow up. CASE PRESENTATION: Herein we report a case of a fourteen-year-old female who presented with worsening pericardial effusion of unknown etiology, and echocardiographic findings of concentric left ventricular hypertrophy, a mildly dilated aortic root and ascending aorta. Her medical history was notable for hemoptysis and an episode of pulmonary hemorrhage secondary to multiple aortopulmonary collaterals that were subsequently embolized in early childhood. She was initially managed with Ibuprofen and Colchicine but continued to worsen, and ultimately required a pericardial window for the management of refractory pericardial effusion. Imaging studies obtained on subsequent visits revealed multiple dilated and tortuous blood vessels in the head, neck, chest, and pelvis. A cardiomyopathy molecular studies panel was sent, and a pathogenic variant was identified in the ABCC9 gene, confirming the molecular diagnosis of autosomal dominant Cantu syndrome. CONCLUSIONS: Vascular anomalies and significant cardiac involvement are often present in Cantu syndrome, however there are currently no established screening recommendations or surveillance protocols in place. The triad of hypertrichosis, facial dysmorphism, and unexplained cardiovascular involvement in any patient should raise suspicion for Cantu syndrome and warrant further investigation. Initial cardiac evaluation and follow up should be indicated in any patient with a clinical and/or molecular diagnosis of Cantu syndrome. Furthermore, whole body imaging should be utilized to evaluate the extent of vascular involvement and dictate long term monitoring and care.

Pinnae and facial hypertrichosis induced by cetuximab.

INTRODUCTION: Anti-EGFR targeted anti-cancer treatment is associated with various skin adverse events. Cetuximab is often associated with acneiform papules and skin disorders. Hypertrichosis cited in face pinnae and eyelash trichomegaly are seldom described. CASE REPORT: A 72-year-old female cancer patient presented deteriorating facial-pinnae hypertrichosis and eyelash prolongation post cetuximab infusion. MANAGEMENT AND OUTCOME: Consecutive cetuximab administration led to exaggerating hairy skin side effects, fully alleviated when the drug was discontinued. DISCUSSION: To the best of our knowledge, this is the first reported case of an anti-EGFR-associated diffuse pinnae hypertrichosis presentation in a female patient in literature. This distinct entity can be easily diagnosed and manipulated with early drug withdrawal. An extensive review of relevant basic molecular research is provided to increase physicians' awareness.

A child with generalized hypertrichosis due to secondary topical minoxidil exposure.

Hypertrichosis is defined as excessive hair growth anywhere on the body in either males or females. It may be caused by genetic conditions, endocrinological disorders, exposure to specific medications (including phenytoin, minoxidil and diazoxide) and other less frequent causes. We report the case of a 1-year-old boy with a family history of thyroid disease and alopecia areata who presented with generalized hypertrichosis due to secondary exposure to topical minoxidil. We discuss an uncommon cause of hypertrichosis and the importance of considering a wide differential diagnosis.

Happle-Tinschert syndrome variable phenotype as part of the mosaic hedgehog spectrum: Report of three cases.

Happle-Tinschert syndrome is a rare genodermatosis caused by a postzygotic mutation in SMO gene. The most recognized clinical findings include segmentally arranged basaloid follicular hamartomas, nevoid hypertrichosis, linear atrophoderma, and hypopigmentation or hyperpigmentation following Blaschko lines associated with osseous, dental, and cerebral alterations. We report three additional cases, two of which lacked the pathognomonic basaloid follicular hamartomas, with genetic confirmation and detailed clinical characterization and describe new cutaneous features of this infrequent syndrome.

Juvenile Dermatomyositis With Rare Cutaneous Manifestation: Generalised Hypertrichosis.

Juvenile dermatomyositis (JDM) is a rare autoimmune disease characterised by inflammation of muscles and skin with extra muscular involvement of joints, heart, intestine, and liver. Pathogenesis of JDM is believed to be due to vasculopathy. Along with classic cutaneous features of JDM, rare findings include hypertrichosis, lipoatrophy, photosensitivity, bullous lesions, and hyperhidrosis. We present, here, a case of JDM with hypertrichosis as very few cases have been reported previously.

Mutations in KCNK4 that Affect Gating Cause a Recognizable Neurodevelopmental Syndrome.

Aberrant activation or inhibition of potassium (K+) currents across the plasma membrane of cells has been causally linked to altered neurotransmission, cardiac arrhythmias, endocrine dysfunction, and (more rarely) perturbed developmental processes. The K+ channel subfamily K member 4 (KCNK4), also known as TRAAK (TWIK-related arachidonic acid-stimulated K+ channel), belongs to the mechano-gated ion channels of the TRAAK/TREK subfamily of two-pore-domain (K2P) K+ channels. While K2P channels are well known to contribute to the resting membrane potential and cellular excitability, their involvement in pathophysiological processes remains largely uncharacterized. We report that de novo missense mutations in KCNK4 cause a recognizable syndrome with a distinctive facial gestalt, for which we propose the acronym FHEIG (facial dysmorphism, hypertrichosis, epilepsy, intellectual disability/developmental delay, and gingival overgrowth). Patch-clamp analyses documented a significant gain of function of the identified KCNK4 channel mutants basally and impaired sensitivity to mechanical stimulation and arachidonic acid. Co-expression experiments indicated a dominant behavior of the disease-causing mutations. Molecular dynamics simulations consistently indicated that mutations favor sealing of the lateral intramembrane fenestration that has been proposed to negatively control K+ flow by allowing lipid access to the central cavity of the channel. Overall, our findings illustrate the pleiotropic effect of dysregulated KCNK4 function and provide support to the hypothesis of a gating mechanism based on the lateral fenestrations of K2P channels.

Expanding the genotypic and phenotypic spectrum in a diverse cohort of 104 individuals with Wiedemann-Steiner syndrome.

Wiedemann-Steiner syndrome (WSS) is an autosomal dominant disorder caused by monoallelic variants in KMT2A and characterized by intellectual disability and hypertrichosis. We performed a retrospective, multicenter, observational study of 104 individuals with WSS from five continents to characterize the clinical and molecular spectrum of WSS in diverse populations, to identify physical features that may be more prevalent in White versus Black Indigenous People of Color individuals, to delineate genotype-phenotype correlations, to define developmental milestones, to describe the syndrome through adulthood, and to examine clinicians' differential diagnoses. Sixty-nine of the 82 variants (84%) observed in the study were not previously reported in the literature. Common clinical features identified in the cohort included: developmental delay or intellectual disability (97%), constipation (63.8%), failure to thrive (67.7%), feeding difficulties (66.3%), hypertrichosis cubiti (57%), short stature (57.8%), and vertebral anomalies (46.9%). The median ages at walking and first words were 20 months and 18 months, respectively. Hypotonia was associated with loss of function (LoF) variants, and seizures were associated with non-LoF variants. This study identifies genotype-phenotype correlations as well as race-facial feature associations in an ethnically diverse cohort, and accurately defines developmental trajectories, medical comorbidities, and long-term outcomes in individuals with WSS.

Hypertrichotic patches as a mosaic manifestation of Proteus syndrome.

BACKGROUND: Proteus syndrome is an overgrowth disorder caused by a mosaic activating AKT1 variant. Hair abnormalities in Proteus syndrome have rarely been reported, and frequencies of such findings have not been elucidated. OBJECTIVE: To define the types and frequencies of hair findings in individuals with Proteus syndrome. METHODS: A cross-sectional study was conducted of individuals with clinical features of Proteus syndrome and a confirmed pathogenic variant in AKT1 evaluated between November 1996 and June 2019 at the National Institutes of Health Clinical Center. Medical records were reviewed for patterning, density, and color of hair on the body and scalp. RESULTS: Of 45 individuals evaluated, 29 (64%) had asymmetric hypertrichosis on the body. This included unilateral blaschkoid hypertrichotic patches overlying normal skin or epidermal nevi in 16 (36%), unilateral nonblaschkoid hypertrichotic patches in 11 (24%), and unilateral limb hypertrichosis in 10 (22%). Diffuse, scattered, or patchy changes in scalp hair density or color were present in 11 individuals (24%). LIMITATIONS: The retrospective, observational design, and limited longitudinal follow-up. CONCLUSIONS: Asymmetric variations in hair distribution, thickness, length, and color contribute to the overall mosaic appearance of the skin in Proteus syndrome, an observation that provides novel insights into the role of phosphoinositide 3-kinase (PI3K)-protein kinase B (AKT) signaling in skin appendage development.

Safety of low-dose oral minoxidil for hair loss: A multicenter study of 1404 patients.

BACKGROUND: The major concern regarding the use of low-dose oral minoxidil (LDOM) for the treatment of hair loss is the potential risk of systemic adverse effects. OBJECTIVE: To describe the safety of LDOM for the treatment of hair loss in a large cohort of patients. METHODS: Retrospective multicenter study of patients treated with LDOM for at least 3 months for any type of alopecia. RESULTS: A total of 1404 patients (943 women [67.2%] and 461 men [32.8%]) with a mean age of 43 years (range 8-86) were included. The dose of LDOM was titrated in 1065 patients, allowing the analysis of 2469 different cases. The most frequent adverse effect was hypertrichosis (15.1%), which led to treatment withdrawal in 14 patients (0.5%). Systemic adverse effects included lightheadedness (1.7%), fluid retention (1.3%), tachycardia (0.9%), headache (0.4%), periorbital edema (0.3%), and insomnia (0.2%), leading to drug discontinuation in 29 patients (1.2%). No life-threatening adverse effects were observed. LIMITATIONS: Retrospective design and lack of a control group. CONCLUSION: LDOM has a good safety profile as a treatment for hair loss. Systemic adverse effects were infrequent and only 1.7% of patients discontinued treatment owing to adverse effects.

H syndrome: A review of treatment options and a hypothesis of phenotypic variability.

H syndrome is a rare autosomal recessive disorder with clinical features comprising: hyperpigmentation, hypertrichosis, hearing loss, heart anomalies, low height, hypogonadism and hepatosplenomegaly. H syndrome results from loss-of-function mutations in SLC29A3 which leads to abnormal proliferation and function of histiocytes. Herein, we discuss the considerable phenotypic heterogeneity detected in a consanguineous Egyptian family comprising of four affected siblings, two of which are monozygotic twin and the possible therapeutics. The phenotypic variability may be attributed to the role of histiocytes in the tissue response to injury. Such variable expressivity of H syndrome renders the diagnosis challenging and delays the management. The different treatment approaches used for this rare entity are reviewed.

Generalized hypertrichosis syndromes in Mexico.

Hypertrichosis is a rare condition characterized by excessive hair in areas of the body that are not predominantly androgen dependent. We can identify three main syndromes with congenital generalized hypertrichosis terminalis described in Mexico. The first is X-linked generalized hypertrichosis, an ultra-rare disease, with few cases reported to date. The second is Cantú syndrome, also known as hypertrichotic osteochondrodysplasia, which has a wide spectrum of clinical manifestations and is caused by pathogenic variants in ABCC9 and KCNJ8. The third is congenital hypertrichosis terminalis with or without gingival hyperplasia, which displays other features and involves several associated genes. The first two syndromes were described by the Mexican geneticist José María Cantú, and the concept of atavistic genes was invoked to explain the emergence of this outstanding trait. By understanding the genetic and pathophysiological basis of hypertrichosis, we can offer effective treatment to patients and help solve esthetic problems related to hair growth.

De Novo Mutations in SLC25A24 Cause a Craniosynostosis Syndrome with Hypertrichosis, Progeroid Appearance, and Mitochondrial Dysfunction.

Gorlin-Chaudhry-Moss syndrome (GCMS) is a dysmorphic syndrome characterized by coronal craniosynostosis and severe midface hypoplasia, body and facial hypertrichosis, microphthalmia, short stature, and short distal phalanges. Variable lipoatrophy and cutis laxa are the basis for a progeroid appearance. Using exome and genome sequencing, we identified the recurrent de novo mutations c.650G>A (p.Arg217His) and c.649C>T (p.Arg217Cys) in SLC25A24 in five unrelated girls diagnosed with GCMS. Two of the girls had pronounced neonatal progeroid features and were initially diagnosed with Wiedemann-Rautenstrauch syndrome. SLC25A24 encodes a mitochondrial inner membrane ATP-Mg/Pi carrier. In fibroblasts from affected individuals, the mutated SLC25A24 showed normal stability. In contrast to control cells, the probands' cells showed mitochondrial swelling, which was exacerbated upon treatment with hydrogen peroxide (H2O2). The same effect was observed after overexpression of the mutant cDNA. Under normal culture conditions, the mitochondrial membrane potential of the probands' fibroblasts was intact, whereas ATP content in the mitochondrial matrix was lower than that in control cells. However, upon H2O2 exposure, the membrane potential was significantly elevated in cells harboring the mutated SLC25A24. No reduction of mitochondrial DNA copy number was observed. These findings demonstrate that mitochondrial dysfunction with increased sensitivity to oxidative stress is due to the SLC25A24 mutations. Our results suggest that the SLC25A24 mutations induce a gain of pathological function and link mitochondrial ATP-Mg/Pi transport to the development of skeletal and connective tissue.

Cholesterol homeostasis: Links to hair follicle biology and hair disorders.

Lipids and lipid metabolism are critical factors in hair follicle (HF) biology, and cholesterol has long been suspected of influencing hair growth. Altered cholesterol homeostasis is involved in the pathogenesis of primary cicatricial alopecia, mutations in a cholesterol transporter are associated with congenital hypertrichosis, and dyslipidaemia has been linked to androgenic alopecia. The underlying molecular mechanisms by which cholesterol influences pathways involved in proliferation and differentiation within HF cell populations remain largely unknown. As such, expanding our knowledge of the role for cholesterol in regulating these processes is likely to provide new leads in the development of treatments for disorders of hair growth and cycling. This review describes the current state of knowledge with respect to cholesterol homeostasis in the HF along with known and putative links to hair pathologies.

PPAR-γ signalling as a key mediator of human hair follicle physiology and pathology.

Peroxisome proliferator-activated receptors (PPARs) are abundantly expressed in human skin, with PPAR-γ being the most intensively investigated isoform. In various ex vivo and in vivo models, PPAR-γ-mediated signalling has recently surfaced as an essential element of hair follicle (HF) development, growth and stem cell biology. Moreover, the availability of novel, topically applicable PPAR-γ modulators with a favourable toxicological profile has extended the range of potential applications in clinical dermatology. In this review, we synthesize where this field currently stands and sketch promising future research avenues, focussing on the role of PPAR-γ-mediated signalling in the biology and pathology of human scalp HFs, with special emphasis on scarring alopecias such as lichen planopilaris and frontal fibrosing alopecia as model human epithelial stem cell diseases. In particular, we discuss whether and how pharmacological modulation of PPAR-γ signalling may be employed for the management of hair growth disorders, for example, in scarring alopecia (by reducing HF inflammation as well as by promoting the survival and suppressing pathological epithelial-mesenchymal transition of keratin 15 + epithelial stem cells in the bulge) and in hirsutism/hypertrichosis (by promoting catagen development). Moreover, we explore the potential role of PPAR-γ in androgenetic alopecia, HF energy metabolism and HF ageing, and consider clinical perspectives that emanate from the limited data available on this so far. As this field of translational human hair research is still in its infancy, many open questions exist, for which we briefly delineate selected experimental approaches that promise to generate instructive answers in the near future.

Severe hypertrichosis in infants due to transdermic exposure to 5% and 7% topical minoxidil.

We report three cases of severe hypertrichosis in healthy infants, who did not present any type of endocrinological pathology and whose parents used topical minoxidil for the treatment of their baldness. Any type of direct application or administration of the product was ruled out. Hypertrichosis is considered to have occurred through skin-to-skin contact with the parent, and even through fomites. Given the widespread use of topical minoxidil, it is likely that this etiology of childhood hypertrichosis is underdiagnosed and that it sometimes leads to minimal forms that go unnoticed.

Evaluation of Safety and Efficacy of Laser Hair Removal With the Long-Pulsed 755 nm Wavelength Laser: A Two-Center Study With 948 Patients.

BACKGROUND AND OBJECTIVES: Laser hair removal is the most common laser therapy and the third most commonly performed procedure with more than one million treatments in United States in 2016. This retrospective study was conducted to assess long-term efficacy and safety of the 755 nm laser for hair removal. STUDY DESIGN/MATERIALS AND METHODS: Nearly, 3,606 laser treatments were performed with the long-pulsed 755 nm wavelength laser equipped with an epidermal cooling device between 1997 and 2005 and were followed till 2013. Standardized assessments were conducted by two treating physicians and patients at two follow-up intervals. At first follow-up, clearance was assessed by two physicians and clearance and satisfaction by patients. At the second follow-up, patients were assessed if hair clearance sustained compared with the first follow-up. RESULTS: Nine hundred and forty-eight patients with Fitzpatrick skin types I-IV were treated with a total of 3,606 laser treatments in this study. The mean age at the beginning of the study was 35 years (±11), 95.1% of patients were female (n = 902) and 4.9% male (n = 46). Five hundred and seventy-four patients received a minimum of three treatments and an average of 5.31 (3-16) treatments on axilla, back, bikini, breast, abdomen, face, lower extremity, or upper extremity region. First, follow-up was conducted 3.9 (±1.5) years after the final laser treatment. Seventy-four percent of these patients received 75-100% clearance as reported by the physician and 48% clearance as reported by the patient. Fifty-two percent of patients reported slower hair growth and 42% change in hair texture. Ninety percent of patients treated on axilla, 82% treated on the bikini area, and 79% treated on lower extremities experienced 75% or more clearance after three treatments. Facial, as well as breast and abdomen treatments, only showed a 66% and 62%, respectively, after three treatments. For these locations, five and more treatments were needed to achieve a quote of 79% (face) or 80% (breast and abdomen) for a 75-100% clearance. Upper extremity and back treatments did not have enough physician ratings to draw conclusions. Long-term adverse events were minimal and were all located on the face (one patient scar, four patients herpes infection). Second follow-up of 173 patients was conducted after 11.5 years (±2.0) and 87.9% of patients reported that their improvement sustained. CONCLUSIONS: The long-pulsed 755 nm alexandrite laser is a safe and efficacious treatment for the reduction of unwanted body hair with permanent results and high patient satisfaction. Lasers Surg. Med. © 2019 Wiley Periodicals, Inc.

H syndrome with a novel homozygous SLC29A3 mutation in two sisters.

H syndrome (OMIM 602782) is a recently defined autosomal recessive genodermatosis. Cutaneous findings of H syndrome include hyperpigmentation, hypertrichosis, and induration, while hearing loss, heart anomalies, hepatomegaly, hypogonadism, hyperglycemia (diabetes mellitus), low height (short stature), hallux valgus (flexion contractures), and hematological abnormalities are the extracutaneous abnormalities. We report a novel homozygous missense mutation, c.416T > C p.(Leu139Pro), in the SLC29A3 (NM_001174098.1) gene in two sisters with H syndrome presenting with different phenotypes.