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. Cases were assigned to three basic clinical groups: I--Urticaria pigmentosa (UP, n=29); II--Mastocytomas (n=4); and III--Diffuse Cutaneous Mastocytosis (DCM, n=2). The analysis of clinical information revealed an association between the presence of diarrhea and a higher number of cells/field. Nine doubtful cases, all of them macules, were selected based on the scarcity of mast cells (MC) and the absence or rarity of other inflammatory cells. We compared the number of cells identified in Giemsa and immunohistochemical stains in definite and doubtful cases. The intraclass correlation statistic tested the concordance between each staining method. All 9 dubious cases according to the Giemsa stain had their CM diagnosis confirmed by the immunohistochemistry analysis. The intraclass correlation between Giemsa and c-kit was good (0.7) when the number of MC was high. However, there was no correlation between the mast cells counts in the two different stains in the dubious cases. The immunohistochemistry with c-kit might make CM diagnosis easier, especially in the macular cases, when there is a lower number of MC.

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. RESULTS: There were 53 (75%) cases of urticaria pigmentosa, 12 (17%) cases of mastocytoma, and six (8%) cases of diffuse cutaneous mastocytosis. In 92% of cases disease onset was in the first year of life. There was a male predominance 1.8 : 1. Treatment did not modify the disease evolution. Eighty per cent of patients improved or had spontaneous resolution of the disease. CONCLUSION: The most frequent clinical form of mastocytosis was urticaria pigmentosa followed by mastocytoma and diffuse cutaneous mastocytosis. Darier's sign was present in 94% of cases. A negative Darier's sign does not rule out mastocytosis. In contrast to adults, mastocytosis in children usually has a benign course making sophisticated or invasive diagnostic tests unnecessary. A classification of paediatric cutaneous mastocytosis is proposed.

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. Clinically, induration was progressive in three patients and regressive in one. Pigmentation was regressive in all. Histopathologically, all four patients showed intense dermal fibrosis, scarce naevus cells, and hypotrophic or absent hair follicles. Follow-up and serial biopsies in three patients documented the progressive nature of fibrosis and naevus cell depletion. No evidence of malignant transformation was found. Naevus cell depletion resulted in pigment loss and may have reduced the risk of malignant transformation. Although the cause of fibrosis is unknown, the possibility of an immune reaction to naevus cells is postulated.

Expression of cyclooxygenase type 2 in lepromatous and tuberculoid leprosy lesions.

BACKGROUND: Leprosy is an infectious disease with two polar forms, tuberculoid leprosy (TL) and lepromatous leprosy (LL), which are dominated by T-helper (Th) 1 and Th2 cells, respectively. High concentrations of prostaglandin E2 produced by the inducible enzyme cyclooxygenase type 2 (COX-2) in LL could inhibit Th1 cytokine production, contributing to T-cell anergy. OBJECTIVES: To compare the COX-2 expression in LL and TL. METHODS: Skin biopsies from 40 leprosy patients (LL, n = 20; TL, n = 20) were used to determine by immunohistochemistry and automated morphometry the percentage of COX-2 immunostained cells. RESULTS: Most COX-2-positive cells were macrophages; their percentages in the inflammatory infiltrate located in the papillary dermis, reticular dermis and periadnexally were significantly higher in LL than TL (P < 0.001 by Student's t-test). CONCLUSIONS: The high expression of COX-2 in LL may be related to high prostaglandin production contributing to T-cell anergy.

Scleroderma 'en coup de sabre' and progressive facial hemiatrophy. Is it possible to differentiate them?

The aim was to be able to evaluate the diagnosis of two diseases by a consensus of clinical opinion used in the Department of Dermatology of the National Institute of Paediatrics in Mexico City. To differentiate between scleroderma 'en coup de sabre' (SCS) and progressive facial hemiatrophy (PFH), colour slides of 13 patients diagnosed as SCS and nine as PFH were examined by two dermatologists and microscopic slides by two pathologists. In both cases, the slides were randomly presented and no clinical information was given. The clinical and histopathological findings were statistically compared with two-tailed tests and alpha = 0.05. Kappa coefficients were obtained to evaluate the concordance between dermatologists, pathologists, and in terms of the consensus diagnosis. The usefulness of photographic assessment is limited by the inability to palpate the consistency of lesions. The most important clinical feature that differentiated both conditions was cutaneous sclerosis present in eight of 13 patients with SCS and in none of the PFH patients (P < 0.005). Other clinical features more frequently found in SCS were cutaneous hyperpigmentation and alopecia. The more frequent clinical features in PFH were total hemifacial involvement and ocular changes. Statistically significant histopathological features were: connective tissue fibrosis present in all cases with SCS and two of nine patients with PFH (P < 0.0002); adnexal atrophy present in 11 of 13 patients with SCS, and in three of nine with PFH (P < 0.02), and mononuclear cell infiltrates in all patients with SCS cf. six with PFH (P < 0.05). Our results suggest that in most cases it is possible to differentiate SCS from PFH based on clinicopathological findings.

Treatment of 18 children with scabies or cutaneous larva migrans using ivermectin.

In addition to onchocerciasis and other filarial diseases, ivermectin has been used for the treatment of scabies, head lice, larva migrans and gnathostomiasis. However, there is concern regarding the safety of its use in children under 5 years of age or weighing less than 15 kg. We present our experience in 18 children (aged 14 months to 17 years), with scabies or cutaneous larva migrans successfully treated with ivermectin. They included four cases of crusted scabies associated with immunosuppression and seven cases of common scabies four of whom had associated clinical mental retardation, immunosuppression or hypomobility. A further seven patients had cutaneous larva migrans. Fifteen patients were cured with a single dose of ivermectin, and three patients with crusted scabies required a second dose. None of our patients suffered significant adverse effects. We believe that ivermectin is a safe and effective alternative treatment of cutaneous parasitosis in children.

A previously unreported syndrome of multiple scalp whorls and associated anomalies.

A 13-month-old male infant with 14 hair whorls in the scalp, sparse frontal hair, wide forehead, ectropion, abnormal implantation of eyelashes, peculiar face and depigmented nipples is reported. Other aspects of his physical and mental development were within normal limits. The constellation of clinical features in this patient appear to represent a previously undescribed syndrome.

Prevalence and nature of nail alterations in pediatric patients.

The purpose of this investigation was to explore the frequency and nature of ungual alterations in patients of a pediatric dermatology department at a third-level pediatric hospital. The first 20 patients with nail alterations seen each year during a 5-year period from 1992 through 1996 were included, totaling 100 patients. The rate of nail alterations was 11% (1/9) in pediatric dermatology patients. There were 5 infants, 19 preschoolers (2- to 5-year-olds), 38 school children (6- to 11-year-olds), and 38 adolescents (12- to 17-year-olds). The most frequent diagnoses were onychomycosis (23), nail alterations in a genodermatosis (23), nail alterations associated with dermatoses (16), onychocryptosis (11), and paronychia (10). Toenails were involved in 54 patients, fingernails in 25, and both in 21 patients. Twenty nails were involved in 21 patients. A high prevalence of nail alterations was found in pediatric dermatology patients, some of which were nonspecific, while others provided important diagnostic clues.

Unusual leukoderma after erythema multiforme: a case report.

Erythema multiforme is an inflammatory disorder of the skin that usually fades without sequelae. It is well known that after inflammatory events, hyper- or hypochromic spots can remain, especially in skin types III-VI, but achromia is very rare. We report a case of residual leukoderma after erythema multiforme.

Malignant melanoma in children and congenital melanocytic nevi: DNA content and cell cycle analysis by flow cytometry.

Malignant melanoma (MM) in children, although a rare neoplasm, can occur within a preexisting congenital melanocytic nevus (CMN). All the potential risk factors for this phenomenon are not well known, but increases in S phase and G2 + M phase of cell cycle, DNA aneuploidy, and cell cycle abnormalities in precursor lesions might be among the risk factors. Using paraffin-embedded tissue, we performed a retrospective analysis of DNA content, aneuploidy, and cell cycle by flow cytometry. Two groups of patients were analyzed: 28 children with CMN who did not developed MM, and 6 patients who further developed MM. In this second group, three patients had four biopsies done before the appearance of MM and in two patients biopsies were done after the appearance of MM. All CMN not associated with MM exhibited diploid cells only, their S phase was 11.5% (+/- 3.8), and their G2 + M phase was 2.5% (+/- 2.2). Among those patients who developed MM, 3/6 had an S phase > 15.5 and a G2 + M phase > 2.3 prior to the appearance of MM. Two out of six patients had a tetraploid DNA when MM developed and died with a disseminated MM. They had an S phase > 15.5 and their G2 + M phase was > 2.5. We propose that evaluation of DNA content and cell cycle by flow cytometry is a useful method to supplement biopsy findings in children with CMN who have lesions suspicious of developing a MM.

Histopathology of vascular lesions found in Kasabach-Merritt syndrome: review based on 13 cases.

We reviewed the histopathology of 13 cases of Kasabach-Merrit Syndrome (KMS). In 4 (31%) cases the predominant morphology was that of a tufted angioma (TA). Six (46%) cases were Kaposiform hemangioendotheliomas (KHE), and 3 (23%) cases showed an infantile (juvenile) hemangioma only. Immunostaining for CD34 and actin (HHF-35) was helpful in defining these types of hemangiomas. The TA was characterized by a proliferation of endothelial cells positive for CD34 with a minimal component of actin-positive cells. KHE showed a paucity of immunoreactive cells; only the luminal endothelial cells were positive for CD34. In three cases with the morphology of infantile hemangiomas, actin-positive cells outnumbered the CD34-positive cells. Our findings confirm the observation that the underlying vascular lesion in KMS is usually not an infantile hemangioma as was originally thought, but variants of hemangiomas such as TA and KHE (77% of 13 KMS cases). Infantile hemangioma was the phenotypic substrate of KMS in only 3 of 13 cases.

Macrodactyly: report of eight cases and review of the literature.

Congenital enlargement of one or several digits of the hands or feet (macrodactyly) is a rare disorder. A considerable proportion of the patients with this condition are referred to dermatology departments. The majority of the cases reported in the literature represent hamartomas with combined hypertrophy of several, predominantly lipomatous, soft tissue components and overgrowth of bone. The differential diagnosis includes Klippel-Trenaunay-Weber syndrome, neurofibromatosis, Milroy disease, and Proteus syndrome. We describe eight cases of congenital macrodactyly, discuss the findings, and propose a simple clinicopathologic terminology.

Bart syndrome: the congenital localized absence of skin may follow the lines of Blaschko. Report of six cases.

Three cutaneous manifestations are characteristic of Bart syndrome: congenital localized absence of skin (CLAS), mucocutaneous blistering, and nail abnormalities. Six cases of Bart syndrome are herein reported. Localized absence of skin is present at birth, particularly on the anterior aspects of the lower extremities and dorsa of the feet. Physical trauma in utero has been proposed as a mechanism to explain the denuded areas on the limbs. The recurrent, highly similar pattern of the congenital defect in regard to location and clinical appearance in our patients and in most of the reported cases strongly suggests that trauma is too simplistic an explanation. Because of the observed bilateral and symmetric distribution of denuded areas in an S-shaped broad band, their sharply demarcated borders, the involvement of the toe webs, and the frequent similar involvement of the soles, we suggest that congenital localized absence of skin in Bart syndrome may follow the lines of Blaschko.