"African" acral keratoderma: Further evidence for a single entity. A retrospective study of 42 patients.

BACKGROUND: Several phenotypes of non-inflammatory palmar and plantar keratoderma (PPK) have been described in patients of Sub-Saharan African descent. They include keratosis punctata of the palmar creases, marginal keratoderma, also known as acrokeratoelastoidosis or focal acral hyperkeratosis, knuckle pads, other forms of diffuse hyperkeratosis, the very rare "mosaic acral keratosis", and ainhum. A previous survey has shown that these various forms of PPK are particularly frequent in patients of Sub-Saharan African descent and that they commonly occur concurrently, suggesting that they could form part of a single entity called "African" Acral Keratoderma (AAK). AIM: To assess the validity of the concept of AAK and clarify its main characteristics. METHODS: A retrospective, descriptive, monocenter study was carried out on patients with AAK seen at our institution between 2009 and 2020. RESULTS: There were 42 patients (median age 38 years, range: 12-69 years), all of Sub-Saharan African descent. The male-female sex ratio was 0.3. Thirty-three (78%) had diffuse keratoderma, 25 (59%) had marginal keratoderma on their hands and/or feet, 20 (48%) had knuckle pads, 20 (48%) had keratosis punctata of the palmar creases, 3 had ainhum, and 2 had mosaic acral keratoderma. Mixed forms were seen in 76% of the patients (n = 32). Familial histories were reported by 17 patients (40%). Treatment was topical in over 90% of patients and systemic in 9 patients (21%). Ainhum was managed surgically. CONCLUSION: This retrospective study provides additional evidence for the concept of AAK. A genetic origin is suggested by the familial aggregation of cases.

[Clinical Characteristics and Gene Mutations in 186 Cases of Kindler Syndrome].

Objective To investigate the clinical characteristics and genetic mutations in Kindler syndrome(KS)and provide a theoretical basis for the diagnosis and treatment of KS. Methods The clinical data of one case of KS from Peking Union Medical College Hospital and 185 cases reported in literature were collected. The gene mutation types,patient clinical data,and tumor characteristics were statistically analyzed. Results A total of 186 cases were enrolled,including 110 males and 76 females,with the mean age of(28±16)years. The data of gene mutation and specific clinical manifestations were available in 151 and 94 patients,respectively. The main clinical manifestations of KS included poikiloderma,occurrence of blister in childhood,and photosensitivity,and the secondary clinical manifestations included oral inflammation,palmoplantar keratoderma,webbing/pseudoainhum,dysphagia,urethral stricture and so on.Oral inflammation(r=0.234,P=0.023),palmoplantar keratoderma(r=0.325,P=0.001),webbing/pseudoainhum(r=0.247,P=0.016),dysphagia(r=0.333,P=0.001),urethral stricture(r=0.280,P=0.006)were significantly correlated with age,showing significantly higher incidence in the patients over 32 years old.Urethral stricture(χ2=11.292,P=0.001)and anal stenosis(χ2=4.014,P=0.045)were significantly correlated with sex,with higher incidence in males.Eighty different mutations were found in 151 patients,and the most common gene mutation was c.676C>T.Forty-one tumors occurred in 27 patients,among which squamous cell carcinoma accounted for 92.7%. The gene mutation site had no significant correlation with squamous cell carcinoma or patient country. Conclusions The c.676C>T in FERMT1 gene is the most common mutation in KS.The patients are prone to squamous cell carcinoma and mainly attacked at the exposure sites(hand and mouth).

Ainhum, a rare mutilating dermatological disease in a female Cameroonian: a case report.

BACKGROUND: Ainhum is an idiopathic dermatological disease characterized by a progressive constricting ring usually on the fifth toe, which may lead to spontaneous auto-amputation of the affected toe. Timely diagnosis and treatment are the key elements to avert amputations with resultant mutilating deformities, permanent handicaps and psychological sequelae. Though common in African descents, this pathology has not been described in the Cameroonian literature. Herein, we report the case of an adult Cameroonian woman presenting with ainhum. CASE PRESENTATION: A 54-year old Cameroonian was admitted to our primary healthcare centre with a 6-month history of a painful constriction band developing at the base of her right fifth toe. Her past history was uneventful. Based on the absence of trauma and spontaneous onset of the condition, the diagnosis of ainhum was most suggestive. She was managed surgically by excision of the band, disarticulated at right fifth metatarsophalangeal joint and skin closure. Her post-operative course after 1 year was uneventful. CONCLUSION: Here we presented a case of ainhum, a rare dermatological disease with few reports. In view of the serious complications of ainhum such as mutilating deformities with permanent physical disabilities and psychological trauma, we draw clinicians' attention, especially wound care specialists to this rare but potentially handicapping disease, for timely diagnosis and management.

Utility of ultrasonography in hair-thread tourniquet syndrome.

A 2-year-old girl presented with a 2-month history of an erythematous, indurated plaque with well-defined borders on the third toe of the right foot. Bedside high-resolution ultrasonography demonstrated a thickened epidermis overlying a hyperechoic focus within the dermis. Her clinical and sonographic presentation was in keeping with a foreign body causing hair-thread tourniquet syndrome. The foreign body was surgically extirpated without neurovascular sequelae. Ultrasonography expedited accurate diagnosis and is a promising adjunct to clinical evaluation for radiolucent foreign bodies.

A novel association of pseudoainhum and epidermolytic ichthyosis, successfully treated with full thickness skin graft after failed z-plasty repair.

Pseudoainhum is a rare constriction band variant thatmay progress to spontaneous digital strangulationand auto-amputation. Although its association withpalmoplantar keratodermas is well established, ithas not been reported in conjunction with classicepidermolytic ichthyosis. We describe the first suchcase in a 25-year-old woman who presented witha painful constricting band of the fifth toe. We alsodescribe her treatment course, which consisted ofa failed z-plasty, the traditional therapeutic optionfor acute pseudoainhum, and report the success ofsubsequent full thickness skin graft, suggesting thebenefit of this procedure as a therapeutic alternativefor patients with pseudoainhum.

An Alternative Surgical Approach to Pseudoainhum: A Case Report.

Pseudoainhum is a disorder of unknown etiology that is usually congenital and nonprogressive. One theory states it is caused by amnion band constriction in utero. These constriction bands lead, not only to a less cosmetically appealing foot, but also to long-term neurovascular compromise, resulting in amputation of the digit. The described surgical approaches have been limited within published data. The 2 procedures that have been described are either a Z-plasty or amputation, depending on the degree of the deformity. The present case report provides an alternative surgical approach to a pseudoainhum deformity of a third digit.

[Ainhum and "African acral keratoderma": three cases]. / Aïnhum et « kératodermies acrales africaines ¼ : trois cas.

BACKGROUND: Ainhum, or spontaneous dactylitis, involves the formation of a gradual constriction in the digital-plantar fold of the fifth toe that leads, after several years, to autoamputation of the digit. This condition is classically distinguished from "true" ainhum, of unknown aetiology and affecting only subjects of African origin, from "pseudo-ainhum", resulting from different causes such as inflammatory constriction or constriction by a foreign body, and finally from ainhumoid palmoplantar keratoderma, which is of genetic origin and occurs for instance in Vohwinkel syndrome. Herein, we report three cases of ainhum in women of sub-Saharan African origin; in addition, all three subjects were also presenting various forms of hyperkeratosis of the hands and feet known to primarily affect subjects of African origin. PATIENTS AND METHODS: The three patients, aged 30, 48 and 44 years, were respectively from Mali, Guinea and Senegal. They had consulted a dermatologist for violent pain in the fifth toe, which frequently prevented sleep and was inexplicable despite several consultations, and even in one case in spite of surgical investigation. Once the diagnosis had been made, relief was promptly provided for all three patients through Z-plasty to remove the circular constriction around the toe in question. In addition to ainhum, the first patient was also presenting diffuse palmoplantar keratoderma, together with an aspect of acrokeratoelastoidosis on the edges of her hands and feet, and knuckle pads, while the second was presenting diffuse palmoplantar keratoderma and an aspect of marginal acrokeratoelastoidosis, and the third was presenting small knuckle pads. DISCUSSION: A recent study has confirmed the high incidence of several forms of palmoplantar keratoderma of African origin, as well as frequent association of these different varieties with one another. These consist of diffuse keratoderma having a relatively non-specific aspect, keratoderma punctata of the palmar creases, marginal keratoderma known also as focal acral hyperkeratosis, and acrokeratoelastoidosis, despite the absence of histological evidence, and finally, inverted keratoderma, i.e. affecting the dorsal aspects of the extremities, such as knuckle pads. In the three cases presented here, ainhum was associated with these different forms of acral keratoderma seen chiefly in subjects of African origin. CONCLUSION: So-called "true" ainhum may be included in a broader group of African acral keratoderma, further reinforcing the unity of this group. Genetic studies are required to enable validation and refinement of these clinical findings.

Ainhum (dactylolysis spontanea): a case with hands and feet involvement.

Dactylolysis spontanea is a rare disease of unknown etiology, basically restricted to digits without systemic involvement. It evolves, in the form of a local constriction, affecting typically the distal phalanx of the fifth toe, rarely involving other toes and even more rarely involving fingers as in the case described herein.

The Voice of the Lost Toe: Pseudo-Ainhum Beyond Skin.

An 11-year-old boy presented with serial autoamputations of the right 4th and 5th toes during the past 6 years. This was associated with sensory loss on the right leg and development of constriction bands around the right 2nd and 3rd digits for the past 5 months. For a year, the patient had been treated with paucibacillary, multi-drug therapy (PB-MDT) with a presumptive diagnosis of leprosy. He was born from a nonconsanguinous marriage and the birth was uneventful. The developmental milestones were normal, and no family history of any congenital anomalies was reported.

Palmoplantar keratoderma, pseudo-ainhum, and universal atrichia: A new patient and review of the palmoplantar keratoderma-congenital alopecia syndrome.

Palmoplantar keratoderma (PPK) may concur with congenital alopecia (CA) in various genodermatoses. We report on a 10-year-old girl with generalized atrichia and a severe form of PPK causing pseudo-ainhum, sclerodactyly, and contractures, a phenotype not consistent with any well-defined condition. Non-specific additional findings comprised mild nail dystrophy and widespread keratosis pilaris including ulerythema ophryogenes. Direct sequencing of the GJB2 and LOR coding regions yielded normal results. A review identified two additional sporadic and four familial cases with PPK and CA. Comparison between familial cases suggested the existence of two genetically and phenotypically distinct types of PPK-CA: (i) an autosomal dominant form (Stevanovic type), a variable and benign phenotype without significant hand complications, and (ii) a more complex autosomal recessive variant (Wallis type) with contractures, sclerodactyly, and pseudo-ainhum. Nuclear cataract may represent an additional although not constant finding in the Wallis type PPK-CA. Further reports are required to test this preliminary conclusion.

Novel mutation p.Gly59Arg in GJB6 encoding connexin 30 underlies palmoplantar keratoderma with pseudoainhum, knuckle pads and hearing loss.

BACKGROUND: Connexins, components of the gap junction, are expressed in several organs including the skin and the cochlea. Mutations in connexin genes including GJB2 (Cx26), GJB3 (Cx31), GJB4 (Cx30.3), GJB6 (Cx30) and GJA1 (Cx43) are responsible for various dermatological syndromes and/or inherited hearing loss, frequently showing overlapping phenotypes. OBJECTIVES: To clarify the spectrum of clinical phenotypes caused by connexin mutations. METHODS: We report a 32-year-old Japanese woman with mild palmoplantar keratoderma (PPK) with severe sensorineural hearing loss, knuckle pads and pseudoainhum of her toes. RESULTS: Direct sequencing revealed no mutation in GJB2, but a novel heterozygous missense mutation p.Gly59Arg in GJB6. Electron microscopy revealed no apparent morphological abnormality of gap junctions in the patient's lesional epidermis. CONCLUSIONS: The patient harboured the novel GJB6 missense mutation p.Gly59Arg in the first extracellular loop of Cx30. Mutations in glycine 59 of Cx26 are associated with PPK-deafness syndrome, and the similar phenotype here supports the observed heteromeric channel formation; the dominant nature of the mutation suggests an effect on gap junctions similar to that of the comparable mutation in Cx26.