Two for two: Dual therapy with erlotinib and acitretin for twins with severe keratoderma in Olmsted syndrome.

Olmsted syndrome (OS) is a rare genetic disorder, characterized by painful palmoplantar keratoderma (PPK), periorificial and intertriginous hyperkeratoses, and alopecia. Fewer than 75 cases have been described. Variants in TRPV3 result in constitutive activation of transient receptor potential vanilloid 3, leading to increased epidermal growth factor receptor (EGFR) signaling, palmoplantar epidermal hyperproliferation, and exquisite lesional pain. We describe pre-school aged twins with OS with partial improvement from oral erlotinib, an EGFR inhibitor, but dramatic reduction of their persistent palmoplantar thickening and pain from adding acitretin.

EGFR Signaling Is Overactive in Pachyonychia Congenita: Effective Treatment with Oral Erlotinib.

Pachyonychia congenita (PC) is a rare keratinizing disorder characterized by painful palmoplantar keratoderma for which there is no standard current treatment. PC is caused by dominant mutations in keratin (K) K6A, K6B, K6C, K16, or K17 genes involved in stress, wound healing, and epidermal barrier formation. Mechanisms leading to pain and painful palmoplantar keratoderma in PC remain elusive. In this study, we show overexpression of EGFR ligands epiregulin and TGF-α as well as HER1‒EGFR and HER2 in the upper spinous layers of PC lesions. EGFR activation was confirmed by upregulated MAPK/ERK and mTOR signaling. Abnormal late terminal keratinization was associated with elevated TGM1 activity. In addition, the calcium ion permeable channel TRPV3 was significantly increased in PC-lesional skin, suggesting a predominant role of the TRPV3/EGFR signaling complex in PC. We hypothesized that this complex contributes to promoting TGM1 activity and induces the expression and shedding of EGFR ligands. To counteract this biological cascade, we treated three patients with PC with oral erlotinib for 6‒8 months. The treatment was well-tolerated and led to an early, drastic, and sustained reduction of neuropathic pain with a major improvement of QOL. Our study provides evidence that targeted pharmacological inhibition of EGFR is an effective strategy in PC.

Aquagenic keratoderma.

BACKGROUND: Aquagenic keratoderma is triggered in the palms and soles after contact with water, and is characterized by the appearance of translucent papules forming macerated plaques. It may be associated with medications and diseases such as cystic fibrosis, atopy, and malnutrition, or be idiopathic. CASE REPORT: We describe the case of a 17-year-old female patient with chronic functional abdominal pain. She presented with a 2-month history of "wrinkling" of palms after contact with water. After stimulation with water, palmar hyperlinearity and whitish, translucent papules forming macerated-looking plaques with a central depression were observed. Dermoscopically, we observed whitish and anfractive structures with coral appearance and microdroplets of water. In the histological study, we observed continuous hyperkeratosis and acrosyringium dilation from the middle dermis to the stratum corneum. With the clinical presentation and histological findings, aquagenic keratoderma was diagnosed, and treatment was started with partial improvement. CONCLUSIONS: Aquagenic keratoderma is an underdiagnosed entity. Despite its indolent course, it could be considered as a marker of a systemic disease such as cystic fibrosis. Since the discussion about the terminology of the disease has arisen, we considered adjusting to a descriptive nomenclature, proposing the term whitish macerated aquagenic plaques of the acrosyringium. It is necessary to continue reporting these cases to understand the disease better and offer adequate management and comprehensive follow-up to the patients.

INTRODUCCIÓN: La queratodermia acuagénica se desencadena tras el contacto de las palmas de las manos y las plantas de los pies con el agua. Se caracteriza por la aparición de pápulas translúcidas que forman placas de aspecto macerado. Puede asociarse con el consumo de ciertos medicamentos y con afecciones como la fibrosis quística, la atopia y la desnutrición, o ser idiopática. CASO CLÍNICO: Se describe el caso de una paciente de 17 años con dolor abdominal crónico funcional. Presentó una dermatosis de 2 meses de evolución que afectaba las palmas con «arrugamiento¼ después del contacto con el agua. Tras el estímulo con el agua, se observaron hiperlinealidad palmar y pápulas blanquecinas y translúcidas que formaban placas de aspecto macerado con una depresión central. Dermatoscópicamente se observaron estructuras blanquecinas anfractuosas de apariencia coraliforme y microgotas de agua. En el estudio histológico se observaron hiperqueratosis continua y dilatación del acrosiringio desde la dermis media hasta el estrato córneo. Con el cuadro clínico y los hallazgos histológicos, se confirmó el diagnóstico de queratodermia acuagénica y se inició el tratamiento, con el que se observó una mejoría parcial. CONCLUSIONES: La queratodermia acuagénica es una afección subdiagnosticada y poco reportada. A pesar de cursar de forma indolente, puede considerarse como un marcador de enfermedad sistémica como la fibrosis quística. Ya que existe discusión sobre la nomenclatura de la enfermedad, consideramos ajustarnos a una nomenclatura descriptiva, como «placas blanquecinas y maceradas acuagénicas del acrosiringio¼. Es necesario continuar reportando estos casos para comprender mejor la enfermedad, ofrecer un manejo adecuado y dar seguimiento integral a los pacientes.

Aquagenic Keratoderma: Treatment Update. / La queratodermia acuagénica: actualización terapéutica.

Aquagenic keratoderma is an uncommon acquired dermatosis characterized by edema and whitish-translucent papules triggered by immersion or contact with water. Cases have been described in association with certain medications, hyperhidrosis, and cystic fibrosis. The aim of this review is to evaluate the effectiveness of different treatments for aquagenic keratoderma. We reviewed the literature and analyzed treatments for aquagenic keratoderma described in case series and reports. Aquagenic keratoderma associated with hyperhidrosis can be treated effectively. Tap water iontophoresis, endoscopic thoracic sympathectomy, botulinum toxin injections, and oxybutynin are effective against refractory forms. Topical salicylic acid and aluminum salts are effective, but of little value as maintenance therapy. Oral oxybutynin 5 mg/d is probably the best option for treating aquagenic keratoderma. The reported pathophysiological effects of nonsteroidal anti inflammatory drugs in this setting suggest that the use of prostaglandins might be justified. Additional studies are needed to investigate these hypotheses and resolve other questions.

Acquired palmoplantar keratoderma associated with primary biliary cholangitis: Complete and persistent resolution after ursodeoxycholic acid treatment.

A 57-year-old woman presenting an acquired and persisting palmoplantar keratoderma associated with primary biliary cholangitis is reported. Treatment with oral ursodeoxycholic acid was prescribed, and a complete and persistent resolution of skin lesions was noted. This observation seems to support that acquired palmoplantar keratoderma is an uncommon cutaneous manifestation of primary biliary cholangitis.

Acitretin-induced periungual pyogenic granulomas and review.

Periungual pyogenic granulomas are benign vascular tumors that present as painful, round, spontaneously bleeding lesions composed of rapidly proliferating capillaries and excess tissue. The vast majority of pyogenic granulomas are caused by physical trauma or infectious agents and they may resolve spontaneously. Herein, we highlight a very rare case of periungual pyogenic granulomas induced by the regularly prescribed oral retinoid acitretin during treatment for congenital palmoplantar keratoderma. This unique case showed that it is feasible to continue acitretin therapy in the presence of pyogenic granuloma development if proper dose reduction and topical therapies are utilized. The patient's lesions resolved within two weeks of this protocol's initiation and the pyogenic granulomas did not recur over the course of a six-month follow-up observation period. In addition, we performed a systematic review of the literature using PubMed databases for the clinical features and treatments in other reported acitretin-induced pyogenic granuloma cases; we compiled a comprehensive list of other prescription drugs known to cause pyogenic granulomas up-to-date.

Effect of Gentamicin Ointment in Patients with Nagashima-type Palmoplantar Keratosis: A Double-blind Vehicle-controlled Study.

Gentamicin ointment has potential in the treatment of Nagashima-type palmoplantar keratosis. However, there is a lack of reliable study data. The aim of this study was to perform a prospective, randomized, double-blinded, contralateral, vehicle-controlled clinical trial. A total of 20 subjects diagnosed with Nagashima-type palmoplantar keratosis by genetic test, who carried nonsense mutations, enrolled in the 30-day study. Gentamicin ointment was applied to the hand and foot on one side of the body, and vehicle ointment was applied to the hand and foot on the other side. The choice of hand and foot in each subject was randomly allocated. The severity of the patient's skin lesions and quality of life were assessed by a blinded evaluator, using the Dermatology Life Quality Index, visual analogue scale scores and digital photography. Gentamicin ointment treatment resulted in a significant improvement in symptoms of hyperkeratosis and foul smell compared with vehicle. No difference was found in the effect on erythema between gentamicin and vehicle. In conclusion, gentamicin ointment demonstrated positive responses and good tolerance in treating Nagashima-type palmoplantar keratosis caused by nonsense mutations.

Treatment of hereditary palmoplantar keratoderma: a review by analysis of the literature.

BACKGROUND: No specific or curative therapy exists for hereditary palmoplantar keratoderma (hPPK), which can profoundly alter patient quality of life, leading sometimes to severe functional impairment and pain. The rarity and the aetiological diversity of this group of disorders can explain the difficulty in comparing the efficacy of available treatments. OBJECTIVES: To review the different treatments tried in patients with hPPK since 2008, their efficacy and safety, with an evaluation of the various therapeutic modalities that can be used to treat hPPK. METHODS: We undertook a comprehensive review of the literature data published since 2008. RESULTS: Only a few case series and individual case reports were identified. Topical (emollients, keratolytics, retinoids, steroids) and systemic treatments (mostly different retinoids), often combined, are used to relieve symptoms. Oral retinoids appear to be the most efficient treatment, but not in all PPK forms, and with variable tolerance. New targeted treatments, according to the specific mechanisms of hPPK, appear promising for the future. CONCLUSIONS: More studies using robust methodology and involving larger cohorts of well-characterized patients (phenotype-genotype) are necessary and should be prioritized by structured networks, such as the European Network for Rare Skin Diseases (ERN-Skin), with the aim of better management of patients with rare skin diseases.