Utilidad de la dermatoscopia en el diagnóstico de las queratosis actínicas pigmentadas / Diagnostic Utility of Dermoscopy in Pigmented Actinic Keratosis

El diagnóstico de las queratosis actínicas pigmentadas puede resultar complicado en la práctica clínica. El diagnóstico diferencial con el lentigo maligno melanoma plantea dificultades, tanto clínica como dermatoscópicamente, ya que ambas entidades pueden presentar características en común. Presentamos 5 casos de queratosis actínicas pigmentadas en 4 pacientes. El hallazgo dermatoscópico más frecuente fue una granulación marrón-grisácea de distribución perifolicular presente en todas las lesiones, seguido de estructuras romboidales en 4 y un patrón anular-granular en 3. En ningún caso se apreciaron salidas foliculares asimétricamente pigmentadas. Destacamos algunas claves que facilitan el diagnóstico preoperatorio de las queratosis actínicas pigmentadas (AU)

The diagnosis of pigmented actinic keratosis can be complicated in clinical practice. The differential diagnosis with lentigo maligna melanoma can be difficult due to common clinical and dermoscopic characteristics. We present 5 cases of pigmented actinic keratosis in 4 patients. The most common dermoscopic finding was a grayish-brown granulation with a perifollicular distribution, present in all lesions, followed by rhomboidal structures in 4 cases, and an annular-granular pattern in 3. In no case were asymmetrical pigmented follicular openings observed. We draw attention to key findings that aid preoperative diagnosis of pigmented actinic keratosis (AU)

MC1R: three novel variants identified in a malignant melanoma association study in the Spanish population.

The human melanocortin-1 receptor (MC1R) gene, which plays a crucial role in pigmentation, also appears to be important in malignant melanoma (MM). This case-control study in the Spanish population included 116 consecutive MM patients and 188 controls frequency matched for sex and age. Sequence analysis of the entire coding region of MC1R was performed, identifying 21 variants, all of them previously reported except for three novel non-synonymous changes: Ser41Phe, Met128Thr and Asn281Ser. Simulated structural analyses suggested disruption of the local structure around Phenylalanine 41, possible destabilization of the hydrophobic interior of the molecule in Threonine 128 and that Asparagine 281 could be in a region of functional importance. The fact that these three novel variants were not present in 1,000 healthy individuals tested adds further weight to them having putative adverse effects on the functional protein. Six variants, all non-synonymous changes, were individually associated with MM risk (Arg160Trp, Asp294His, Val60Leu, Val92Met, Ile155Thr and Arg163Gln). Carrying two non-synonymous variants was associated with much higher risk of MM (odds ratio: 10.44, 95% confidence interval = 4.48-24.33, P = 5 x 10(-8)) and haplotype analysis, verified by cloning, confirmed that this is predominantly due to carrying each on a different chromosome. Our results suggest that both red hair colour (RHC) and non-red hair colour variants, and possibly other rare non-synonymous variants, in MC1R are implicated in the development of MM. In addition to carrying MC1R variant alleles, having blond/red hair and childhood sunburns were independent risk factors for MM.

Dermatitis sistémica de contacto por tetracaínas / Tetracaine-induced systemic contact-type dermatitis

Varón de 71 años que presenta lesiones eccemato-purpúricas en zona inguinal, de un día de evolución. 48 horas antes se le había practicado una resección transuretral por hipertrofia benigna de próstata. Durante la intervención se le aplicó el anestésico tópico tetracaína, base del denominado “lubricante urológico” (LU), exclusivamente en la sonda uretral y glande. El paciente refería que en anteriores ocasiones había tenido fisuras perianales tras la aplicación de cremas antihemorroidales. Se le realizó biopsia y pruebas alérgicas de contacto que incluyeron la batería estándar de alergenos y los propios del LU. A las 24 y a las 48 horas se confirmó resultado positivo a la mezcla de caínas (+ + +) y LU (+ + +). El LU tópico fue testado en 20 pacientes control, resultando negativo en todos ellos. El diagnóstico fue de eccema sistémico de contacto por caínas. El proceso se resolvió en 7-10 días tras aplicación tópica de corticosteroides, y la toma de antihistamínicos orales

We report the case of a 71-year-old-man with dermatitis in the groin area. Forty-eight hours previously, he had undergone transurethral resection for benign prostatic hyperplasia. During the prostatectomy, the probe was lubricated with a urological ointment containing the topical anesthetic, tetracaine. The patient had previously experienced severe pruritus and fissures in the perianal area after using antihemorrhoidal ointments. Biopsy and patch testing with the standard series and lubricant ointment showed positive reactions to this lubricant, called “urological lubricant” (UL) (+ + +) with caine mix (+ + +). The patient was diagnosed with systemic contact-type dermatitis due to caine mix. The dermatitis improved with topical steroids and oral antihistamine agents

Dermatitis atópica / Atopic dermatitis

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Granuloma anular profundo / Deep granuloma annulare

El granuloma anular es un proceso inflamatorio granulomatoso cutáneo, de etiología desconocida, que aparece con mayor frecuencia en la infancia, que no suele acompañarse de síntomas clínicos importantes y para el que no se dispone de tratamientos efectivos. La evolución es favorable y en la mayoría de los casos es autorresolutiva sin tratamiento. Se han descrito cuatro formas clínicas de granuloma anular: localizado, generalizado, perforante y profundo; el que nos atañe es el granuloma anular profundo, que se puede confundir principalmente con el eritema nodoso y con los nódulos reumatoides. (AU)