Immunohistochemical differentiation of four benign eccrine tumors

Background:  The histogenesis and differentiation of eccrine tumors, including cylindroma, poroma, spiradenoma and syringoma, remains controversial. This controversy may be because of sporadic and incomplete studies of these neoplasms.
Methods:  Ten examples each of normal eccrine structures and of four benign eccrine tumors are analyzed with antibodies to cytokeratin (CK) 7, CD34, CK6, CK10, smooth muscle actin (SMA) and CD10. These markers represent two different immunohistochemical stains for each part of the eccrine structure; CK7 and CD34 stain the secretory coil, CK6 and CK10 stain the straight duct and SMA and CD10 stain the myoepithelial cells. This redundancy in staining is performed on four benign eccrine tumors to better interpret the existing literature.
Results:  We find that CK7 is a sensitive marker for the secretory coil; both cylindromas and spiradenomas express CK7. We also find that CK6 is a marker for the inner ductal cells, while CK10 is a marker for the middle ductal cells; syringomas express both these markers. SMA appears to be a more specific marker for myoepithelial cells surrounding normal eccrine coils, and none of the studied tumors express SMA or CD10.
Conclusions:  Our studies suggest that syringomas are tumors of the eccrine duct, while cylindromas and spiradenomas are tumors of the secretory coil.     

Metalworking exposures and persistent skin symptoms in the ECRHS II and SAPALDIA 2 cohorts

Background:  Diseases of the skin are important and often preventable conditions occurring among workers with dermal exposures to irritant and sensitizing agents.
Objective:  We conducted this analysis to assess the associations between metalworking exposures and current and persistent skin symptoms among male and female participants in two population-based epidemiologic studies.
Methods:  We pooled data from the European Community Respiratory Health Survey II (ECRHS II) and the Swiss Cohort Study on Air Pollution and Lung and Heart Disease in Adults 2 (SAPALDIA 2), two prospective cohort studies in Europe. Each participant completed interviewer-administered questionnaires to provide information about symptoms and exposures related to selected occupations, including metalworking, during the follow-up periods. We assessed associations between skin symptoms and the frequency of metalworking exposures among 676 ECRHS II/SAPALDIA 2 respondents.
Results:  Current skin symptoms were reported by 10% of metalworkers and were associated with frequent use, defined as four or more days per week, of oil-based metalworking fluids [prevalence ratio (PR): 1.76, 95% confidence interval (CI): 1.25–2.49)] and organic solvent/degreasing agents (PR: 2.06, 95% CI: 1.21–3.50).
Conclusions:  Skin symptom prevalence is associated with increasing frequency of oil-based metalworking fluid and degreasing agent use. Our findings justify assessing strategies for reducing the frequency of metal-related exposures.     

Immunohistochemistry and polymerase chain reaction on paraffin-embedded material improve the diagnosis of cutaneous leishmaniasis in the Amazon region

Background  Recently, there has been an increase in the incidence of cutaneous leishmaniasis (CL), which represents an important health problem. This increase may be related to the epidemiologic expansion of the infective agent and the increase in tourism in tropical areas. The difficulty in clinical diagnosis, mainly in areas in which CL is not the first consideration of local physicians, has intensified efforts to describe diagnostic tests, which should be specific, sensitive, and practical. Amongst the new tests described are those including nucleic acid amplification (polymerase chain reaction, PCR) and immunohistochemistry (IHC).
Methods  In this study, we evaluated the sensitivity of a PCR based on small subunit (SSU) ribosomal DNA, in comparison with IHC using Leishmania spp. antibodies, in biopsies embedded in paraffin.
Result  The results indicated a total sensitivity of 96% (90.9% with PCR and 68.8% with IHC), showing the possibility of using paraffin-embedded biopsies to diagnose CL.
Conclusion  We propose the use of the two tests together as a routine protocol for diagnosis. This would require the provision of local medical services to perform molecular biology techniques and adequate Leishmania antibodies.     

Basement membrane reconstruction in human skin equivalents is regulated by fibroblasts and/or exogenously activated keratinocytes

This study was undertaken to examine the role fibroblasts play in the formation of the basement membrane (BM) in human skin equivalents. For this purpose, keratinocytes were seeded on top of fibroblast-free or fibroblast-populated collagen matrix or de-epidermized dermis and cultured in the absence of serum and exogenous growth factors. The expression of various BM components was analyzed on the protein and mRNA level. Irrespective of the presence or absence of fibroblasts, keratin 14, hemidesmosomal proteins plectin, BP230 and BP180, and integrins alpha1beta1, alpha2beta1, alpha3beta1, and alpha6beta4 were expressed but laminin 1 was absent. Only in the presence of fibroblasts or of various growth factors, laminin 5 and laminin 10/11, nidogen, uncein, type IV and type VII collagen were decorating the dermal/epidermal junction. These findings indicate that the attachment of basal keratinocytes to the dermal matrix is most likely mediated by integrins alpha1beta1 and alpha2beta1, and not by laminins that bind to integrin alpha6beta4 and that the epithelial-mesenchymal cross-talk plays an important role in synthesis and deposition of various BM components.     

Exogenous ochronosis and striae atrophicae following the use of bleaching creams

Exogenous ochronosis is a paradoxical hyper-pigmentation of the skin caused by the long-term use of hydroquinone-containing bleaching creams. Ochronosis is an uncommon condition characterized by yellow-brown pigmented deposits in the dermis. We report two cases of exogenous ochronosis in two female patients of the sub-Saharan African population. The lesions were characterized by an asymptomatic hyper-pigmentation of the face with gradually progressive blue-black macular patches, and in case no. 2, in addition to dyschromic lesions, striae atrophicae were present. This phenomenon is the outcome of the use of skin care products containing high concentrations of hydroquinone- and glucocorticoid-based products, and, in addition, certain modalities in the use of bleaching products are likely to facilitate complications.     

Spitz nevus is relatively frequent in adults: a clinico-pathologic study of 247 cases related to patient's age

Spitz nevus is a clinico-pathologic entity that can cause diagnostic concern, particularly in adults. Many studies have been performed to establish reliable histologic criteria, in the attempt to differentiate this lesion from melanoma. A series of 247 Spitz nevi, 6 of which were formerly classified as melanomas, were reviewed for clinical and histopathological parameters. Patients older than 20 comprised 66% of cases, with a predominance of women. The lower extremity was more affected in females of any age, whereas the trunk was more frequently involved in men over 40. Histopathologic examination showed the following differences among Spitz nevi related to age: acanthosis, parakeratosis, pagetoid infiltration, and Kamino bodies were more frequent in young people, whereas multinucleated melanocytes were more frequent in adults. The latter also had lesions that were less pigmented, with less maturation and more desmoplasia. At a mean follow-up of 94 months (range 52-172), recurrence at the site of biopsy or metastases were absent. In our study, a greater proportion of Spitz nevi occurred in adults than in previous series. Moreover, the relative incidence of Spitz nevus compared with melanoma in our population was higher than in other studies. Histopathologic criteria elaborated to diagnose Spitz nevus, applied to our cases, appeared reliable, allowing a correct diagnosis, even in adults.     

Treatment of hemorrhagic lymphatic malformation of the tongue with a pulsed-dye laser

Hemorrhagic lymphatic malformation (formerly called hemolymphangioma) of the tongue is an uncommon malformation that may pose both functional and cosmetic problems for the patient. The challenge has been to find a conservative treatment with low morbidity and better results than those achieved with surgical excision, which has been the mainstay of therapy. We report a case of successful treatment of a hemorrhagic lymphatic malformation of the tongue with a variable-pulse 595-nm pulsed-dye laser (Vbeam; Candela Corp, Wayland, Mass). In this patient, pulsed-dye laser treatment of the hemorrhagic lymphatic malformation achieved satisfactory functional and cosmetic outcomes. Its use in superficial vascular lesions of the mucosa should be considered.     

Bacterial flora of leg ulcers in patients admitted to Department of Dermatology, Poznań University of Medical Sciences, during the 1998-2002 period

Venous leg ulcers are an important cause of morbidity in a significant percentage of the world population. The percentage of leg ulceration, either active or healed, in the European population is about 1%-2%. The aim of this study was to analyze the rate of colonization and qualitative composition of the bacterial flora isolated from leg ulcers in patients admitted to Dermatology Department, Poznań University of Medical Sciences, during the 1998-2002 period, with special reference to the infection risk factors. Bacteriological diagnosis of 175 wound swabs was performed in compliance with compulsory laboratory methods. In 173 positive results, the predominant culture composition included Staphylococcus aureus (56.57%), Pseudomonas aeruginosa (37.14%), Enterococcus faecalis (22.29%), Proteus mirabilis (13.71%) and Escherichia coli (12.57%). There was a significant increase in the incidence of Pseudomonas aeruginosa, Enterococcus faecalis and Escherichia coli, along with a decrease in the incidence of Staphylococcus aureus isolation during the study period. The rate of yeast-like fungi strains, mainly Candida albicans, recorded in culture composition showed a systematic increase. Changes in the qualitative and quantitative composition of bacterial flora, presence of multiple isolates, and concomitant diseases that may influence the characteristics of leg ulcer disease were closely monitored.     

Intravitreal bevacizumab in aggressive posterior retinopathy of prematurity.

The anatomic response to intravitreal bevacizumab injection in three patients with aggressive, posterior retinopathy of prematurity is described. In all cases, the worse eye was treated with a single intravitreal injection of 0.75 mg of bevacizumab as monotherapy or complementary to laser therapy. In 24 hours, all injected eyes showed regression of the tunica vasculosa lentis and iris vessel engorgement and disappearance of iris rigidity. In addition, plus disease and retinal proliferation began to regress. None of the eyes required additional treatment. Follow-up of up to 10 months