Pigmented purpuric eruption associated with injection medroxyprogesterone acetate.

Pigmented purpuric eruptions are characterized clinically by purpura, most commonly petechial, and brownish pigmentation. Although there are several idiopathic variants, several drugs have been associated with these eruptions. We present a patient who experienced pigmented purpura on her lower extremities several months after initiating medroxyprogesterone acetate injection. The eruption cleared several weeks after discontinuation of the medication.

Progression to invasive melanoma from malignant melanoma in situ, lentigo maligna type.

We have previously hypothesized that lesions that have been termed lentigo maligna can be divided into 2 categories: 1 represents a pigmented lesion that is a precursor to melanoma, and the other melanoma in situ. We and others have hypothesized that there is a progressive acquisition of attributes in pigmented lesions that results in malignant melanoma. Based on these 2 hypotheses, we have predicted that the intraepidermal component of invasive malignant melanomas, lentigo maligna type, should be similar to those lesions that we have termed malignant melanoma in situ, lentigo maligna type rather than lentigo maligna. The intraepidermal component of 42 consecutive cases of invasive malignant melanoma, lentigo maligna type was evaluated by all of the authors. Malignant melanoma in situ, lentigo maligna type is characterized by pagetoid spread, confluence, and nesting of atypical melanocytes. All of the cases evaluated showed features diagnostic of malignant melanoma in situ, lentigo maligna type, in the epidermis overlying the invasive dermal component. We conclude that invasive lentigo maligna melanoma arises in association with those lesions that we have termed malignant melanoma in situ, lentigo maligna type, which may represent a step in the progression between atypical melanocytic hyperplasia (lentigo maligna) and invasive melanoma. This finding supports the distinction of these entities and may have therapeutic implications.

Nitric oxide synthase in toxic epidermal necrolysis and Stevens-Johnson syndrome.

Toxic epidermal necrolysis and Stevens-Johnson syndrome are severe cutaneous drug reactions of unknown mechanism. Nitric oxide can cause apoptosis and necrosis. The inducible form of nitric oxide synthase generates large amounts of nitric oxide and has been described in human skin. We propose that a large burst of nitric oxide in toxic epidermal necrolysis and Stevens-Johnson syndrome may cause the epidermal apoptosis and necrosis. Skin biopsies were taken from seven patients with actively progressing Stevens-Johnson syndrome or toxic epidermal necrolysis. Expression of inducible nitric oxide synthase was examined by reverse transcription-polymerase chain reaction and by immunoperoxidase staining for inducible nitric oxide synthase protein. Messenger RNA for inducible nitric oxide synthase was detected by reverse transcription-polymerase chain reaction and confirmed by the sequencing of polymerase chain reaction products. Strong staining for inducible nitric oxide synthase was observed in inflammatory cells in the lower epidermis and upper dermis. Diffuse, weaker staining was observed in keratinocytes. Expression of inducible nitric oxide synthase is consistent with the hypothesis that nitric oxide mediates the epidermal necrosis in toxic epidermal necrolysis and provides a potential target for therapeutic intervention.

Tools of the trade: statistical analysis in dermatopathology articles.

Statistical analysis of research results provides powerful tools for understanding the data from projects. A prospective review of the statistical methods utilized in 100 consecutive articles in the recent literature relevant to dermatopathology was performed. The majority of papers, 75%, did not contain statistical analyses. A wide variety of methods were utilized in the papers that did have statistical analyses including methods in the following categories: t-test, contingency tables, multiple regression, multiple comparisons, nonparametric tests, life tables, and survival tests. Nine of the 25 papers utilizing statistical analysis had problems in the methods. These problems included treating categorical data as a continuous variable, multiple comparisons, subgroup analysis, and discordance of statistics and conclusions. It is important to understand the underlying assumptions of statistical methods to use the appropriate tets. These are tools of the trade for dermatopathology investigators.

Postpartum and vulvar necrotizing fasciitis. Early clinical diagnosis and histopathologic correlation.

OBJECTIVE: To review the clinical course and correlate histopathologic findings of obstetrics and gynecology patients with necrotizing fasciitis STUDY DESIGN: Seven-teen patients with postpartum or vulvar necrotizing fasciitis were identified from 1981 to 1996. Medical records were retrospectively reviewed. Information was available for all patients until death or discharge from the hospital. Histopathologic material on 15 patients was available for review. RESULTS: Five postpartum patients were diagnosed and surgically debrided one to nine days after cesarean delivery, with no mortality. Twelve patients with vulvar necrotizing fasciitis were diagnosed and surgically debrided <1-10 days after presentation to a physician, with three deaths (25%). On histopathologic review, all cases had prominent lobular and septal panniculitis. Thirteen cases had histologic evidence of fasciitis. CONCLUSION: Early diagnosis and aggressive surgical debridement in patients with postpartum and vulvar necrotizing fasciitis may improve the outcome. Histopathologic findings are remarkably consistent and may help to confirm the diagnosis.

From bedside to the bench and back. Nitric oxide and the cutis.

When the discoverer of dynamite (trinitrotoluene [TNT]), Alfred Nobel, was prescribed nitroglycerin for angina in 1895, he was certainly taken aback. Almost a century later, organic nitrates and their gaseous metabolic end product, nitric oxide (NO), were implicated in a vast array of biologically diverse activities. About 10 years ago, a series of discoveries from different avenues of research converged on NO, thrusting it into the limelight as a neurotransmitter, vasodilator, toxin, and modulator of immune function and inflammation. Nitric oxide has thus managed to capture the interest of scientists from a number of fields and holds center stage attention. Interest in NO among dermatologists has been slow to appear, however, and the literature on NO with respect to the skin is sparse when compared with the steep escalation in the number of articles published generally on NO since 1987 (Figure 1).

An unusual pustular eruption in an infant with Down syndrome and a congenital leukemoid reaction.

Congenital leukemia and leukemoid reactions may be indistinguishable on clinical and histologic grounds and are highly associated with trisomy 21. This report characterizes a specific vesiculopustular skin eruption in an infant with Down syndrome and a congenital leukemoid reaction. On the first day of life an unusual vesiculopustular eruption developed, starting in areas of cutaneous trauma. A biopsy revealed immature myeloid cells in an epidermal spongiotic vesiculopustule and in a perivascular distribution, suggestive of leukemia cutis. As the peripheral blood smear normalized, the eruption cleared. Myelodysplasia subsequently developed and evolved into acute myelogenous leukemia. This is the first detailed report of a specific skin infiltrate caused by the immature cells of a leukemoid reaction. Skin infiltration by immature myeloid cells during a congenital leukemoid reaction may portend an aggressive course of the myeloproliferative disorder.