Usefulness of the skin biopsy as a tool in the diagnosis of silvery hair syndrome.

Background/objectives: Silvery hair syndrome is a rare, autosomal-recessive entity characterized by silvery gray hair, eyebrows, and eyelashes and may be associated or not with immunologic or neurologic alterations. Two main types have been recognized: Chediak-Higashi syndrome and Griscelli syndrome. Hair shaft examination under light microscopy has been a useful tool to differentiate Chediak-Higashi syndrome from Griscelli syndrome, although distribution of melanin varies according to hair color related to ethnicity.

Rhabdomyomatous Mesenchymal Hamartoma: A Deep Subcutaneous Lesion in the Sternoclavicular Area.

Cutaneous rhabdomyomatous mesenchymal hamartoma (RMH) is a rare benign tumor composed of two or more types of mesenchymal-derived cells. RMHs are generally sporadic and independent, but they can be associated with congenital abnormalities. We report a subcutaneous case of RMH in the sternoclavicular area with two recurrences after complete surgical excision.

Hydroa vacciniforme-like lymphoma: a chronic EBV+ lymphoproliferative disorder with risk to develop a systemic lymphoma.

Hydroa vacciniforme-like lymphoma (HVLL) is an Epstein-Barr virus (EBV)-positive T-cell lymphoproliferative disorder of childhood that occurs mainly in Central and South America and Asia. We present the clinicopathological features of 20 Mexican children with HVLL with a median age of 8 years at diagnosis (range, 1-15). All patients presented with skin lesions involving sun-exposed areas, but not exclusively.

Dermoid cysts: a report of 75 pediatric patients.

Dermoid cysts (DCs) are benign cutaneous tumors that tend to persist and grow. The aim of this study was to examine the clinicopathologic features of congenital DCs. We present a case series of 75 children with a clinicopathologic diagnosis of DC.

Common Dermatoses in Children Referred to a Specialized Pediatric Dermatology Service in Mexico: A Comparative Study between Two Decades.

Background. Skin diseases among pediatric patients differ from those in adults. Epidemiological studies are scarce, and those performed in Mexican population date back thirty years.

Less common clinical manifestations of atopic dermatitis: prevalence by age.

The common manifestations of atopic dermatitis (AD) appear sequentially with involvement of the cheeks in infancy, flexural extremities in childhood, and hands in adulthood. Although less common clinical manifestations are well described, they have not been the subject of epidemiologic studies to describe their prevalence in specific age groups. This observational, cross-sectional, comparative study included 131 children younger than 18 of both sexes with AD who attended the clinics of the Dermatology Department of the National Institute of Pediatrics in Mexico City.

Congenital cutaneous angioleiomyoma.

Congenital cutaneous angioleiomyoma is an extremely rare benign smooth muscle tumor. We present a case of a firm, painful subcutaneous mass noticed at birth on the left leg that on surgical excision proved to be an angioleiomyoma. Prognosis is good, and recurrences are uncommon.

Hypomelanotic conditions of the newborn and infant.

Depigmented nevi, pityriasis alba, and postinflammatory hypopigmentation are the most frequent hypomelanotic conditions in newborns and infants. These, and examples of less frequent hypopigmentations are briefly discussed in this article. A new classification for depigmented nevi is also proposed.

Mastocytosis in children: clinicopathological study based on 35 cases.

Immunohistochemical staining is useful in the diagnosis of bone marrow infiltration in systemic mastocytosis. However, it is not clear if antibody staining may be helpful in the diagnosis of cutaneous mastocytosis (CM). We studied the histological appearance of CM in 35 pediatric patients.

Keratosis lichenoides chronica in pediatric patients: a different disease?

Keratosis lichenoides chronica (KLC) is a rare acquired disease of adulthood, of unknown etiology, characterized by keratotic parallel linear lesions, retiform plaques, and keratotic, often follicular papules, chronicity and lichenoid histopathologic features. KLC of pediatric onset is considered extremely rare. Its features and relationship to adult onset KLC are unknown.

Medallion-like dermal dendrocyte hamartoma: a new clinically and histopathologically distinct lesion.

Dermal dendrocyte hamartomas are extremely rare; only two examples have been described with clinical features different from our cases and with incomplete immunohistochemical characterization. We report three female patients presenting a medallion-shaped, well-defined, slightly atrophic and asymptomatic congenital lesion. All 3 patients showed a fusiform-cell proliferation.

Epidermal nevus syndromes: clinical findings in 35 patients.

Of the patients with epidermal nevi, 10-18% may have disorders of the eye, nervous, and musculoskeletal systems. A predisposition to malignant neoplasms in ectodermal and mesodermal structures may also be found. There are six different epidermal nevus syndromes described so far: Proteus, congenital hemidysplasia with ichthyosiform nevus and limb defect syndrome, phakomatosis pigmentokeratotica, sebaceous nevus, Becker nevus, and nevus comedonicus.

Dermatitis artefacta in pediatric patients: experience at the national institute of pediatrics.

Dermatitis artefacta is a factitious disorder in which there is deliberate conscious production of skin lesions. There are only a few reports that evaluate instances of dermatitis artefacta in the pediatric population. The aim of this retrospective study was to assess the characteristics of patients with this disorder who were seen at the National Institute of Pediatrics in Mexico City.

Cutaneous mastocytosis in children: a clinical analysis of 71 cases.

Objective: To characterize the clinical features, response to therapy, evolution and prognosis of cutaneous mastocytosis in children.

Background: Mastocytosis in children, instead of being induced by a potentially oncogenic c-kit mutation, is probably a clonal disease with benign prognosis.

Methods: The clinicopathological features, evolution and response to treatment were analysed in 71 children with mastocytosis.

Desmoplastic hairless hypopigmented naevus: a variant of giant congenital melanocytic naevus.

Desmoplasia has been described in melanoma and Spitz naevus but not in giant congenital melanocytic naevus (GCMN). In melanoma desmoplasia is associated with a better survival. Four paediatric patients with hard, ligneous, progressively hypopigmented and alopecic GCMN were seen among 143 cases of GCMN at the Department of Dermatology of the National Institute of Paediatrics, Mexico City.