Complement Activation and STAT4 Expression Are Associated with Early Inflammation in Diabetic Wounds

Diabetic non-healing wounds are a major clinical problem. The mechanisms leading to poor wound healing in diabetes are multifactorial but unresolved inflammation may be a major contributing factor. The complement system (CS) is the most potent inflammatory cascade in humans and contributes to poor wound healing in animal models. Signal transducer and activator of transcription 4 (STAT4) is a transcription factor expressed in immune and adipose cells and contributes to upregulation of some inflammatory chemokines and cytokines. Persistent CS and STAT4 expression in diabetic wounds may thus contribute to chronic inflammation and delayed healing. The purpose of this study was to characterize CS and STAT4 in early diabetic wounds using db/db mice as a diabetic skin wound model. The CS was found to be activated early in the diabetic wounds as demonstrated by increased anaphylatoxin C5a in wound fluid and C3-fragment deposition by immunostaining. These changes were associated with a 76% increase in nucleated cells in the wounds of db/db mice vs.

CONTROLS

The novel classical CS inhibitor, Peptide Inhibitor of Complement C1 (PIC1) reduced inflammation when added directly or saturated in an acellular skin scaffold, as reflected by reduced CS components and leukocyte infiltration. A significant increase in expression of STAT4 and the downstream macrophage chemokine CCL2 and its receptor CCR2 were also found in the early wounds of db/db mice compared to non-diabetic controls. These studies provide evidence for two new promising targets to reduce unresolved inflammation and to improve healing of diabetic skin wounds.

Scanning Electron Microscopic Hair Shaft Analysis in Ectodermal Dysplasia Syndromes

OBJECTIVES

The objective of the current study was to catalog hair shaft abnormalities in individuals with ectodermal dysplasia (ED) syndromes using scanning electron microscopy (SEM) and to compare the findings with those in unaffected controls. This is the second of a two-part study, the first of which used light microscopy as the modality and was previously published.

METHODS

Scanning electron microscopy was performed in a blinded manner on hair shafts from 65 subjects with seven types of ED syndromes and 41 unaffected control subjects. Assessment was performed along the length of the shaft and in cross section.

SETTING

Hair donations were collected at the 28th Annual National Family Conference held by the National Foundation for Ectodermal Dysplasia. Control subjects were recruited from a private dermatology practice and an academic children's hospital outpatient dermatology clinic.

RESULTS

SEM identified various pathologic hair shaft abnormalities in each type of ED and in control patients. When hairs with all types of ED were grouped together and compared with those of control patients, the difference in the presence of small diameter and shallow and deep grooves was statistically significant (p < 0.05). When the EDs were separated according to subtype, statistically significant findings were also seen.

CONCLUSION

SEM is a possible adjuvant tool in the diagnosis of ED syndromes. There are significant differences, with high specificity, between the hairs of individuals with ED and those of control subjects and between subtypes.

Persistent edematous-plaque photosensitivity observed with sitagliptin phosphate (Januvia®)

Photosensitivity to sitagliptin, a dipeptidyl peptidase-4 (DPP-4) inhibitor, is reported. No previous reports of photosensitivity to any DPP-4 inhibitors are known. Physical examination of the patient revealed edematous plaques confined to sun-exposed areas of the skin. An unusual finding in this case was the spongy sensation upon palpation of the plaques. Histopathology revealed parakeratosis and abundant eosinophils, supporting the clinical impression of cutaneous drug sensitivity. The eruption finally cleared, approximately two years after onset.

Comparative diagnostic accuracy in virtual dermatopathology

BACKGROUND

Virtual microscopy can be used to teach histology and pathology and for in-training and certification examinations. A few online consultation websites already utilize virtual microscopy, thereby expanding the role of telemedicine in dermatopathology. There are, however, relatively few studies comparing the diagnostic accuracy and acceptability of virtual slides compared to traditional glass slides.

METHODS

Ten Nordic dermatopathologists and pathologists were given a randomized combination of 20 virtual and glass slides and asked to identify the diagnoses. They were then asked to give their impressions about the virtual images. Descriptive data analysis and comparison of groups using Fisher's exact test were performed.

OBJECTIVE

To compare the diagnostic ability of dermatopathologists and pathologists in two image formats: the traditional (glass) microscopic slides, and whole mount digitized images, and to elucidate their assessment of virtual microscopy in dermatopathology.

RESULTS

Dermatopathologists and pathologists performed similarly in diagnosing dermatopathological disorders using virtual slides vs. glass slides, virtual 0.85 and glass 0.81, P=0.286. The order of administration of virtual or glass slides did not affect the percentage of questions answered correctly. Seven of nine participants completing the questionnaire, felt virtual microscopy is useful for both learning and testing.

CONCLUSION

There was no significant difference in the participants' diagnostic ability using virtual slides compared with glass slides. Most participants agreed that virtual microscopy is a useful tool for learning and testing.

Sweet syndrome in infancy

Sweet syndrome, or acute febrile neutrophilic dermatosis, is characterized by the presence of fever, peripheral leukocytosis, painful erythematous plaques and nodules, and a predominately neutrophilic dermal infiltrate. We report a case occurring in a 10-week-old male child, with preceding upper respiratory tract, and gastrointestinal infection symptoms. Sweet syndrome occurring in an infant should prompt a work-up for immunodeficiency, as well as a review of the peripheral blood smear to rule out the rare case of malignancy.

Nevi of Special Sites

Melanocytic nevi can have a wide range of histologic appearances. Within the spectrum of nevi, there exists a group that presents in certain anatomic locations with histologically worrisome features but nonetheless benign behavior. This group of nevi has been broadly categorized as nevi of special sites. The anatomic locations affected by this group include the embryonic milkline (breast, axillae, umbilicus, genitalia), flexural areas, acral surfaces, ear, and scalp. Nevi in these locations may be mistaken for melanomas because of their histologic appearance, resulting in inappropriate overtreatment of patients. In this article, the authors review the histologic features of these special site nevi and discuss the criteria that help distinguish them from melanoma.

Patient safety: Part I. Patient safety and the dermatologist

Congress is grappling with ways to fund health care in the future. Much of the focus rests on paying physicians for their patients' outcomes, rather than the current system of payment for services provided during each visit. The years ahead will be years of change for American health care, with an increasing emphasis on the comparison of patient outcomes and measures of quality. Patient safety initiatives will be an integral part of the overall strategy to improve American health care. Part one of this two-part series on patient safety examines what we know about patient safety in dermatology, including data from medicolegal claims and published data on patient safety in the setting of office-based surgery. The article also focuses on how medical societies, payers, the US government, and the Board of Medical Specialties are responding to calls for accountability and improvements in patient safety.

LEARNING OBJECTIVES

After completing this learning activity, participants should be able to identify risks to patient safety based on an understanding of the major causes of legal claims against dermatologists, use published patient safety data to improve the practice of office surgery, and be able to improve patient safety through an understanding of requirements for maintenance of certification.

Acquired acrodermatitis enteropathica secondary to alcoholism

Acrodermatitis enteropathica is a zinc deficiency disorder characterized by well-demarcated, erythematous, eczematous plaques in a periorificial and acral distribution. Hereditary and acquired forms have been described. We report a case of acquired acrodermatitis enteropathica secondary to alcoholism. Treatment of the underlying disorder and zinc replacement therapy resulted in rapid resolution of the condition.

A fatal case of dermatomyositis with underlying metastatic esophageal adenocarcinoma

Dermatomyositis (DM) is known to be associated with underlying malignancy, though the strength of this relationship and its predisposing factors are not clearly defined. We present a case of a patient who was first diagnosed with DM and, subsequently, metastatic esophageal adenocarcinoma. Despite aggressive immunosuppressive therapy, the patient's cutaneous eruption failed to resolve and his muscle weakness progressed. He had respiratory failure and died less than 2 months after his initial presentation. To our knowledge, this is only the second case of metastatic esophageal adenocarcinoma associated with DM reported in the English language literature.

Laptop computer-induced erythema ab igne: a case report

Erythema ab igne is a condition characterized by reticulated telangiectasia and hyperpigmentation caused by repeated long-term exposure to infrared radiation insufficient to produce a burn. We report a case of laptop computer-induced erythema ab igne.

The association between malignant melanoma and noncutaneous malignancies

BACKGROUND

Both increases and decreases in the incidence of subsequent malignancies in melanoma patients have been reported. We examined the database of the Indiana University Cancer Center to determine whether there is an association between malignant melanoma and noncutaneous malignancies.

OBJECTIVE

We searched for evidence of noncutaneous malignancies in a cohort of melanoma patients.

METHODS

Patients with microscopically confirmed malignant melanoma diagnosed between January 1987 and March 2001 were analyzed. This cohort was investigated for noncutaneous malignancies occurring either before or after the diagnosis of melanoma. The standardized incidence ratios (SIR) were calculated as the ratio of the observed to the expected number of patients with second malignancies, and 95% confidence intervals (95% CI) around the SIR were estimated from the cumulative Poisson distribution.

RESULTS

A total of 955 patients with melanoma (498 males and 457 females) were documented over the 14-year period. Sixty-nine noncutaneous malignancies were identified in 59 (6.2%) melanoma patients (39 males and 20 females). There was a higher risk of non-Hodgkin's lymphoma (SIR = 1.91; 95% CI, 0.88-3.62) in men and renal cell carcinoma (SIR = 2.41, 95% CI, 0.97-4.97) in men. In female patients, however, there was no higher risk of noncutaneous malignancies.

CONCLUSIONS

This study did not show a higher risk of prostate cancer, gastrointestinal cancer, leukemia, endometrial cancer, or cancer of the nerve and neuroendocrine systems in melanoma patients. No female patients incurred a higher risk of noncutaneous cancers. The increased risk of non-Hodgkin's lymphoma and renal cell carcinoma in men might be attributed to a mutual carcinogenic exposure, an aberration of cell-mediated immunity, a shared genetic susceptibility, increased medical surveillance among cancer patients, a post-therapy effect after cancer management, or factors not as yet clear. Close monitoring of melanoma patients for signs of second malignancy is warranted.

Proliferative nodules with balloon-cell change in a large congenital melanocytic nevus

The balloon-cell nevus was first described over 100 years ago. Since then, balloon-cell changes of melanocytes have been noted in numerous tumors, including melanoma, blue nevus, and Spitz nevus. Whether these changes reflect cellular deterioration or proliferative changes is a matter of debate. We report a case in which balloon-cell changes were found within proliferative nodules occurring in a large congenital melanocytic nevus.

Subungual pleomorphic fibroma

BACKGROUND

Pleomorphic fibroma is a benign fibroblastic tumor characterized by pleomorphic, hyperchromatic cells or giant multinucleated cells embedded in a collagenous stroma. These cytologic features may lead to an incorrect diagnosis of malignancy. Most cases reported in the literature are located on trunk or extremities; the presentation as a subungual mass is rare.

METHODS

We report an unusual case of a subungual pleomorphic fibroma in 66-year-old woman. Clinical information was obtained. Histologic examination and immunohistochemical studies were performed.

RESULTS

A 66-year-old woman presented with a longstanding (40 years), subungual mass that deformed the nail of the left middle finger. Microscopic examination revealed a paucicellular tumor composed of hyperchromatic spindled, pleomorphic, floret-like giant cells embedded in haphazardly arranged collagen bundles in the dermis. No mitotic figures were seen. The tumor cells were vimentin-positive but did not stain with antibodies to S-100, cytokeratin, smooth muscle actin, factor XIIIa or CD34 negative. The diagnosis of a pleomorphic fibroma was made. Follow-up shows no evidence of tumor, 36 months after excision.

CONCLUSION

Pleomorphic fibroma of the subungual region is an unusual cutaneous tumor with histologic features that may cause confusion with true sarcomas. This is only the second case reported of a subungual pleomorphic fibroma. Pleomorphic fibroma should be considered in the differential diagnosis of pleomorphic subungual tumors.

Histopathologic recognition of involved margins of lentigo maligna excised by staged excision: an interobserver comparison study

OBJECTIVES

To assess interobserver and intraobserver concordance for identifying positive and negative margins in staged excisions of lentigo maligna and lentigo maligna melanoma and to determine if control biopsy specimens are useful to improve concordance.

DESIGN

Retrospective, randomized interobserver and intraobserver comparison study of archived pathologic specimens. The study was conducted in 3 phases, and slides were evaluated blindly and independently by 5 pathologists: in phase 1, all slides were randomized and diagnosed as positive or negative. In phase 2, every third slide was evaluated again and diagnosed as positive or negative. In phase 3, slides were organized into cases, allowing evaluation of each margin in the context of the positive control (tumor from the center of the lesion) and negative control (control biopsy specimen), if available.

SETTING

University referral center.

STUDY MATERIAL

A total of 301 glass microscopic slides from 27 patients who underwent staged excision for lentigo maligna or lentigo maligna melanoma from March 1997 to April 2001.

MAIN OUTCOME MEASURES

Interobserver and intraobserver concordance between original diagnoses and study diagnoses rendered on all slides by 5 pathologists.

RESULTS

Phase 1 and 3 agreement was moderate (kappa range, 0.4-0.5). Phase 2 (intraobserver) agreement was moderate to good for all pathologists (kappa range, 0.6-0.9). Subset analysis revealed a statistically significant increase in agreement with the use of a control strip biopsy specimen for difficult slides.

CONCLUSIONS

Interobserver concordance for margin analysis in lentigo maligna and lentigo maligna melanoma is moderate, and intraobserver concordance is moderate to good. A control strip biopsy specimen may improve concordance in some cases.

Endothelial induction of the T-cell chemokine CCL21 in T-cell autoimmune diseases

The signals that mediate T-cell infiltration during T-cell autoimmune diseases are poorly understood. The chemokine CCL21 (originally isolated by us and others as Exodus-2/6Ckine/SLC/TCA4) is highly potent and highly specific for stimulating T-cell migration. However, it is thought to be expressed only in secondary lymphoid organs, directing naive T cells to areas of antigen presentation. It is not thought to play a role in T-cell effector function during a normal immune response. In this study we tested the expression of T-cell chemokines and their receptors during T-cell autoimmune infiltrative skin diseases. By using immunohistology it was found that the expression of CCL21 but not CCL19 or 20 was highly induced in endothelial cells of T-cell autoimmune diseases. The receptor for CCL21, CCR7, was also found to be highly expressed on the infiltrating T cells, most of which expressed the memory CD45Ro phenotype. These data imply that the usual loss of CCL21 responsiveness in the normal development of memory T-cell effector function does not hold for autoimmune skin diseases.

Evolution of the cutaneous immune response to experimental Haemophilus ducreyi infection and its relevance to HIV-1 acquisition

Haemophilus ducreyi causes the sexually transmitted disease chancroid, which facilitates HIV-1 transmission. Skin biopsies were obtained from subjects experimentally infected with H. ducreyi to study the evolution of the immune response and immunophenotypes relevant to transmission of HIV-1. Compared with peripheral blood, there was an enrichment of T cells and macrophages after 48 h of infection in the skin. Neutrophils became the predominant cell type by 7-9 days. By immunohistochemistry, macrophage-inflammatory protein-1alpha was not present early in infection, but was abundant at later stages. RANTES was present throughout the papular and pustular stages of experimental infection, but not present in uninfected control skin. Stromal cell-derived factor-1 was present at low levels in all samples examined. Macrophages in lesions had significantly increased expression of CCR5 and CXCR4 compared with peripheral blood cells, and CD4 T cells had significant up-regulation of CCR5. The magnitude of increased expression of these receptors was not replicated when PBMCs were incubated with H. ducreyi or H. ducreyi lipooligosaccharide in vitro. Together with the disruption of mucosal and skin barriers, the presence of cells with up-regulated HIV-1 coreceptors in H. ducreyi-infected lesions may provide an environment that facilitates the acquisition of R5 (CCR5), X4 (CXCR4), and dual-tropic HIV-1 strains.

Awareness of the risks of tanning lamps does not influence behavior among college students

HYPOTHESIS

Awareness of the risks of artificial tanning influences tanning behavior among college students.

OBJECTIVE

To correlate the prevalence of tanning lamp use, the perceived benefits and risks associated with UV exposure, and knowledge about skin cancer among university students.

DESIGN

A survey was designed and administered to college students seeking "walk-in" care at a university student health center from September 7, 1999, through September 30, 1999.

SETTING

A large midwestern public university student health center.

PARTICIPANTS

Undergraduate and graduate students attending the student health center for any medical condition.

INTERVENTION

None.

MAIN OUTCOME MEASURE

Completion of the survey.

RESULTS

Of the surveyed students, 47% had used a tanning lamp during the preceding 12 months. Female students were more common users than male students. Of the students surveyed, 39% reported never having used tanning lamps. More than 90% of users of tanning lamps were aware that premature aging and skin cancer were possible complications of tanning lamp use.

CONCLUSIONS

Despite adequate knowledge of the adverse effects of UV exposure, university students freely and frequently use tanning lamps, primarily for desired cosmetic appearance. To alter this risky behavior will require a fundamental change in the societal belief that tans are attractive and healthy.

Three-dimensional imaging of human skin and mucosa by two-photon laser scanning microscopy

BACKGROUND

Various structural components of human skin biopsy specimens are difficult to visualize using conventional histologic approaches.

METHODS

We used two-photon microscopy and advanced imaging software to render three-dimensional (3D) images of in situ nerves, blood vessels, and hair follicles labeled with various fluorescent markers. Archived frozen human skin biopsy specimens were cryosectioned up to 150 micro m in thickness and fluorescently stained with rhodamine- or fluorescein-labeled antibodies or lectins. Optical sections were collected by two-photon microscopy and the resulting data sets were analyzed in three dimensions using Voxx software.

RESULTS

Reconstructed image volumes demonstrated the complex 3D morphology of nerves, blood vessels and adnexal structures in normal mucocutaneous tissue.

CONCLUSION

Two-photon microscopy and Voxx rendering software allow for detailed 3D visualization of structures within human mucocutaneous biopsy specimens, as they appear in situ, and facilitate objective interpretation of variations in their morphology. These techniques may be used to investigate disorders involving cutaneous structures that are difficult to visualize by means of traditional microscopy.

Enhanced cutaneous inflammatory reactions to Aspergillus fumigatus in a murine model of chronic granulomatous disease

Chronic granulomatous disease is the manifestation of genetic defects of the leukocyte NADPH oxidase resulting in the absence of a respiratory burst. Patients with chronic granulomatous disease can develop chronic granulomas in many locations of the body, including the skin. Using an established murine model of X-linked chronic granulomatous disease (X-CGD) created by homologous recombinant disruption of the gene encoding the gp91phox component of the NADPH oxidase, in this study we examined cutaneous reactivity to sterile Aspergillus fumigatus hyphae. Injection of Aspergillus fumigatus into the dorsal ears of X-CGD mice resulted in an enhanced inflammatory response by 24 h, consisting of neutrophils, which developed into suppurative granulomas by 10 d. Intradermal injection of Aspergillus fumigatus into wild-type mice only resulted in a transient inflammatory response that resolved by 10 d. Injection of Aspergillus fumigatus into female carrier mice resulted in an acute inflammatory response that was similar to that of wild-type mice, but, at higher doses of Aspergillus fumigatus, many carriers subsequently developed granulomatous lesions that were qualitatively similar but smaller than those seen in X-CGD mice by 30 d. Consistent with the ability of X-CGD mice to mount an enhanced neutrophil-rich inflammatory response to Aspergillus fumigatus, significant levels of the potent neutrophil activator/chemoattractant leukotriene B4 were measured by mass spectrometry in skin biopsies at 24 and 72 h. In contrast to the exaggerated inflammatory response to intradermal Aspergillus fumigatus in X-CGD mice compared to their wild-type counterparts, similar levels of inflammation were seen in a model of delayed-type hypersensitivity using 2,4-dinitrofluorobenzene. This study represents the first report of a cutaneous granuloma model in mice with X-CGD, which may also prove useful as a functional test to evaluate the efficacy of gene therapy protocols being developed for chronic granulomatous disease.

A superoxide dismutase C mutant of Haemophilus ducreyi is virulent in human volunteers

Haemophilus ducreyi produces a periplasmic copper-zinc superoxide dismutase (Cu-Zn SOD), which is thought to protect the organism from exogenous reactive oxygen species generated by neutrophils during an inflammatory response. We had previously identified the gene, sodC, responsible for the production and secretion of Cu-Zn SOD and constructed an isogenic H. ducreyi strain with a mutation in the sodC gene (35000HP-sodC-cat). Compared to the parent, the mutant does not survive in the presence of exogenous superoxide (L. R. San Mateo, M. Hobbs, and T. H. Kawula, Mol. Microbiol. 27:391-404, 1998) and is impaired in the swine model of H. ducreyi infection (L. R. San Mateo, K. L. Toffer, P. E. Orndorff, and T. H. Kawula, Infect. Immun. 67:5345-5351, 1999). To test whether Cu-Zn SOD is important for bacterial survival in vivo, six human volunteers were experimentally infected with 35000HP and 35000HP-sodC-cat and observed for papule and pustule formation. Papules developed at similar rates at sites inoculated with the mutant or parent. The pustule formation rates were 75% (95% confidence intervals [CI], 43 to 95%) at 12 parent-inoculated sites and 67% (95% CI, 41 to 88%) at 18 mutant-inoculated sites (P = 0.47). There was no significant difference in levels of H. ducreyi recovery from mutant- and parent-inoculated biopsy sites. These results suggest that expression of Cu-Zn SOD does not play a major role in the survival of this pathogen in the initial stages of experimental infection of humans.

Vascular inflammation (vasculitis) in sweet syndrome: a clinicopathologic study of 28 biopsy specimens from 21 patients

BACKGROUND

Sweet syndrome is characterized by painful, erythematous plaques of rapid onset accompanied by fever. Absence of vasculitis is a histologic criterion for diagnosis. However, recent reports suggest that vasculitis should not exclude the diagnosis. We hypothesized that vasculitis can occur in Sweet syndrome and that it represents an epiphenomenon rather than a primary immune-mediated process.

DESIGN

Skin biopsy specimens from patients with Sweet syndrome were reviewed to determine the prevalence of vasculitis. The clinicopathologic features of cases with vasculitis were evaluated for statistically significant associations. Specimens with vasculitis underwent immunofluorescence staining.

SETTING

University department of dermatology, university hospital, and private practice.

PATIENTS

Medical records and biopsy specimens of 21 patients meeting diagnostic criteria for Sweet syndrome were reviewed.

INTERVENTIONS

None.

RESULTS

The prevalence of vasculitis was 29% (6 of 21 patients). There was a significant association of vasculitis with lesions of longer duration (P =.02). Vascular immunoglobulin and complement could not be demonstrated in cases of Sweet syndrome with vasculitis.

CONCLUSIONS

Vasculitis is not a primary, immune-mediated process in Sweet syndrome but occurs secondary to noxious products released from neutrophils. Blood vessels in lesions of longer duration are more likely to develop vasculitis than those of shorter duration because of prolonged exposure to noxious metabolites. Vasculitis does not exclude a diagnosis of Sweet syndrome.

Haemophilus ducreyi lipooligosaccharide mutant defective in expression of beta-1,4-glucosyltransferase is virulent in humans

The lipooligosaccharide (LOS) of Haemophilus ducreyi contains a major glycoform that is immunochemically identical to paragloboside, a glycosphingolipid precursor of major human blood group antigens. We recently identified the gene responsible for the glucosyltransferase activity and constructed an isogenic mutant (35000glu-) deficient in this activity. 35000glu- makes an LOS that consists only of the heptose trisaccharide core and 2-keto-deoxyoctulosonic acid (KDO). For this study, the mutant was reconstructed in the 35000HP (human passaged [HP]) background. Five human subjects were inoculated with 35000HP and 35000HPglu- in a dose-response trial. The pustule formation rates were 40% (95% confidence interval [CI], 13.7 to 72.6%) at 10 sites for 35000HP and 46.7% (95% CI, 24.8 to 69.9%) at 15 sites for 35000HPglu-. The histopathology and recovery rates of H. ducreyi from surface cultures and biopsies obtained from mutant and parent sites were similar. These results indicate that the expression of glycoforms with sugar moieties extending beyond the heptose trisaccharide core is not required for pustule formation by H. ducreyi in humans.

Calciphylaxis is associated with hyperphosphatemia and increased osteopontin expression by vascular smooth muscle cells

Calciphylaxis or calcific uremic arteriolopathy (CUA) is a fatal disease in dialysis patients due to calcification of cutaneous blood vessels. The pathogenesis has been attributed to elevated parathyroid hormone (PTH). However, recent studies evaluating vascular calcification in nondialysis patients have found that the smooth muscle cells play an active role, including production of the bone matrix protein osteopontin. To examine the involvement of various clinical parameters and smooth muscle cells of CUA, we performed a case-control analysis comparing 10 CUA patients with our current dialysis patients. Available histologic sections were immunostained for osteopontin, markers of smooth muscle cells, endothelial cells, and macrophages. Compared with our current dialysis population, patients with CUA were more likely to be obese, white, and female (P < 0.02). Comparison of laboratory values found CUA patients with lower serum albumin, greater serum phosphorus, and greater calcium X phosphorus product (P < 0.01). In contrast, there was no difference in the concentration of PTH or calcium between the 2 groups. Immunostaining of calcified blood vessels showed that all calcified vessels stained positive for osteopontin, whereas all the noncalcifed vessels showed no osteopontin localization. Staining for smooth muscle alpha-actin decreased in the medial layer with calcification, with cells appearing to be sloughed off, leading to near occlusion of the vessel lumen. Our case-control study demonstrates that hyperphosphatemia and an elevated calcium X phosphorus product is associated with CUA. Histologic examination suggests that the calcification is associated with increased expression of osteopontin by smooth muscle cells.

Expression of cytolethal distending toxin and hemolysin is not required for pustule formation by Haemophilus ducreyi in human volunteers

Haemophilus ducreyi makes cytolethal distending toxin (CDT) and hemolysin. In a previous human challenge trial, an isogenic hemolysin-deficient mutant caused pustules with a rate similar to that of its parent. To test whether CDT was required for pustule formation, six human subjects were inoculated with a CDT mutant and parent at multiple sites. The pustule formation rates were similar at both parent and mutant sites. A CDT and hemolysin double mutant was constructed and tested in five additional subjects. The pustule formation rates were similar for the parent and double mutant. These results indicate that neither the expression of CDT, nor that of hemolysin, nor both are required for pustule formation by H. ducreyi in humans.

DsrA-deficient mutant of Haemophilus ducreyi is impaired in its ability to infect human volunteers

Haemophilus ducreyi produces an outer membrane protein called DsrA, which is required for serum resistance. An isogenic dsrA mutant, FX517, was constructed previously in H. ducreyi 35000. Compared to its parent, FX517 cannot survive in normal human serum. When complemented in trans with a plasmid containing dsrA, FX517 is converted to a serum-resistant phenotype (C. Elkins, K. J. Morrow, Jr., and B. Olsen, Infect. Immun. 68:1608-1619, 2000). To test whether dsrA was transcribed in vivo, we successfully amplified transcripts in five biopsies obtained from four experimentally infected human subjects. To test whether DsrA was required for virulence, six volunteers were experimentally infected with 35000 and FX517 and observed for papule and pustule formation. Each subject was inoculated with two doses (70 to 80 CFU) of live 35000 and 1 dose of heat-killed bacteria on one arm and with three doses (ranging from 35 to 800 CFU) of live FX517 on the other arm. Papules developed at similar rates at sites inoculated with the mutant or parent. However, mutant papule surface areas were significantly smaller than parent papules. The pustule formation rate was 58% (95% confidence interval [CI] of 28 to 85%) at 12 parent sites, and 0% (95% CI of 0 to 15%) at 18 mutant sites (P = 0.0004). Although biosafety regulations precluded our testing the complemented mutant in humans, these results suggest that expression of DsrA facilitates the ability of H. ducreyi to progress to the pustular stage of disease.

Expression of peptidoglycan-associated lipoprotein is required for virulence in the human model of Haemophilus ducreyi infection

Haemophilus ducreyi expresses a peptidoglycan-associated lipoprotein (PAL) that exhibits extensive homology to Haemophilus influenzae protein 6. We constructed an isogenic PAL mutant (35000HP-SMS4) by the use of a suicide vector that contains lacZ as a counterselectable marker. H. ducreyi 35000HP-SMS4 and its parent, 35000HP, had similar growth rates in broth and similar lipooligosaccharide profiles. 35000HP-SMS4 formed smaller, more transparent colonies than 35000HP and, unlike its parent, was hypersensitive to antibiotics. Complementation of the mutant in trans restored the parental phenotypes. To test whether expression of PAL is required for virulence, nine human volunteers were experimentally infected. Each subject was inoculated with two doses (41 to 89 CFU) of live 35000HP and one dose of heat-killed bacteria on one arm and with three doses (ranging from 28 to 800 CFU) of live 35000HP-SMS4 on the other arm. Papules developed at similar rates at sites inoculated with the mutant or parent but were significantly smaller at mutant-inoculated sites than at parent-inoculated sites. The pustule formation rate was 72% (95% confidence interval [CI], 46.5 to 90.3%) at 18 parent sites and 11% (95% CI, 2.4 to 29.2%) at 27 mutant sites (P < 0.0001). The rates of recovery of H. ducreyi from surface cultures were 8% (n = 130; 95% CI, 4.3 to 14.6%) for parent-inoculated sites and 0% (n = 120; 95% CI, 0.0 to 2.5%) for mutant-inoculated sites (P < 0.001). H. ducreyi was recovered from six of seven biopsied parent-inoculated sites and from one of three biopsied mutant-inoculated sites. Confocal microscopy confirmed that the bacteria present in a mutant inoculation site pustule lacked a PAL-specific epitope. Although biosafety regulations precluded our testing the complemented mutant in humans, these results suggest that expression of PAL facilitates the ability of H. ducreyi to progress to the pustular stage of disease.

The frequency of histologically dysplastic nevi in 199 pediatric patients

Many uncertainties surround the definition, frequency, and significance of dysplastic nevi in children. Consequently the management of dysplastic nevi in the pediatric population has been largely derived from the studies of adults. Biopsies are usually performed on this young age group because of lesion change or abnormal appearance. One might therefore assume that the frequency of histologically diagnosed dysplastic nevi would be higher in children than in adults. We decided to attempt to verify this assumption by determining the frequency of dysplastic nevi diagnosed histologically in the pediatric population. To do this we reviewed 199 cutaneous pathology reports of nevi removed from patients less than 18 years old and submitted to a community-based dermatopathology laboratory. The diagnosis of dysplastic nevus was made based on histologic criteria recommended by the World Health Organization Melanoma Program. We found that 3 of 199 nevi submitted for histologic analysis met the histologic criteria for dysplastic nevus. There were no melanomas. Our data suggest that there is an extremely low frequency of histologically confirmed dysplastic nevi within the general pediatric population.

Lobular capillary hemangiomas: An epidemiologic report, with emphasis on cutaneous lesions

BACKGROUND

Lobular capillary hemangiomas (pyogenic granulomas) occur on both mucosal and cutaneous surfaces. There are conflicting data regarding the increased prevalence of lobular capillary hemangiomas in female versus male subjects. Some studies have noted a female predominance of lobular capillary hemangiomas, but other studies do not reveal such a disparity. Because of an increased prevalence during pregnancy, oral tumors are also known as "granuloma gravidarum" or "pregnancy tumors." A hormonal influence for these mucosal lesions has been postulated. There are, however, no studies that address a possible relationship between hormones and cutaneous lesions.

OBJECTIVE

This study presents the epidemiology of lobular capillary hemangiomas, with an emphasis on cutaneous lesions.

METHODS

We reviewed 63,759 dermatopathology reports from a regional, private dermatopathology laboratory and found 325 cases of lobular capillary hemangiomas over a 1-year period.

RESULTS

In our study of lobular capillary hemangiomas, cutaneous lesions accounted for 86%, with mucosal lesions representing only 12% of cases. Seven cases were excluded (one was intravascular, two were subcutaneous, and in 4 the location was not specified). Overall, male patients outnumbered female patients. The peak incidence for cutaneous lobular capillary hemangiomas was found in the second decade of life. The most common cutaneous sites were the trunk, upper extremities, and head. Mucosal lesions were primarily seen on the lips, gingiva, and tongue, and these affected females more than males by a ratio of 2:1, most commonly in the fourth decade of life.

CONCLUSION

Cutaneous lobular capillary hemangiomas were equally prevalent in male and female patients. This would refute a female hormonal influence in the induction of cutaneous lobular capillary hemangiomas. Our data may suggest a hormonal influence on mucosal lesions because mucosal lobular capillary hemangiomas were twice as common in female patients. However, the small number of lesions in our study precludes us from making such a conclusion.

Evaluation of an isogenic major outer membrane protein-deficient mutant in the human model of Haemophilus ducreyi infection

Haemophilus ducreyi expresses 2 OmpA homologs, designated MOMP and OmpA2, whose genes are arranged in tandem on the chromosome. Northern blot analysis indicated that momp and ompA2 are transcribed independently. Sequences of the momp open reading frame (ORF) lacking the transcriptional start site were amplified by PCR, and an Omega-Km2 cassette was ligated into the ORF. A plasmid containing this construction was electroporated into H. ducreyi 35000HP, and an isogenic MOMP-deficient mutant (35000HP-SMS2) was generated by allele exchange. In Southern blotting, 35000HP-SMS2 contained one copy of the Omega-Km2 cassette in momp. 35000HP and 35000HP-SMS2 had similar outer membrane protein (OMP) and lipooligosaccharide profiles and growth rates except for up-regulation of a putative porin protein in the mutant. Five subjects were inoculated with three doses of live 35000HP-SMS2 on one arm and two doses of live 35000HP and one dose of a heat-killed control on the other arm in a double-blind escalating dose-response trial. Pustules developed at 7 of 10 sites inoculated with 35000HP and at 6 of 15 sites inoculated with 35000HP-SMS2 (P = 0.14). 35000HP and 35000HP-SMS2 were recovered at similar rates from daily surface cultures and semiquantitative cultures. The data suggest that expression of MOMP is not required for pustule formation by H. ducreyi in the human model of infection.

Epithelioid sarcoma arising on the nose of a child: a case report and review of the literature

A 4-year-old boy presented with a 6-month history of a red papule on the nasal septum. Physical examination was otherwise unremarkable. A biopsy specimen showed an epithelioid sarcoma characterized by nodular collections of epithelioid tumor cells with central, tumor cell necrosis. By immunohistochemistry the tumor cells were positive for cytokeratin, epithelial membrane antigen, vimentin, and CD34, but negative for S-100, CD31, factor VIII-related antigen, CD68, actin, desmin and myoglobin. Epithelioid sarcoma is an uncommon tumor of uncertain histogenesis that typically arises in the extremities of young adults. Both the age of our patient and the location of his tumor are unusual, emphasizing the spectrum of presentations that may occur with epithelioid sarcoma. Epithelioid sarcoma should be considered in the differential diagnosis of granulomatous diseases and epithelioid tumors of children, even in unusual locations.

An isogenic hemoglobin receptor-deficient mutant of Haemophilus ducreyi is attenuated in the human model of experimental infection

Haemophilus ducreyi expresses a conserved hemoglobin-binding outer-membrane protein (HgbA). To test the role of HgbA in pathogenesis, we infected 9 adults with isolate 35000 and its isogenic hgbA-inactivated mutant (FX504) on their upper arms in a double-blinded, escalating dose-response study. Papules developed at similar rates at sites inoculated with the mutant or parent. The pustule-formation rate was 55% (95% confidence interval [CI], 30. 8%-78.5%) at parent sites and 0 (95% CI, 0-10.5%) at mutant sites (P<.0001). The recovery rate of H. ducreyi from surface cultures was 16% (n=142) from parent sites and 0 (n=213) from mutant sites (P<. 0001). H. ducreyi was recovered at biopsy from 6 of 7 parent sites and from 0 of 3 mutant sites. The results indicate that hemoglobin may be a critical source of heme or iron for the establishment of H. ducreyi infection in humans.

A pilus-deficient mutant of Haemophilus ducreyi is virulent in the human model of experimental infection

Haemophilus ducreyi expresses fine tangled pili, which are composed predominantly of a major subunit (FtpA). Confocal microscopy showed that an FtpA-specific monoclonal antibody bound to bacteria in biopsy samples obtained from infected human volunteers. To test the role of pili in pathogenesis, an isogenic mutant (35000HP-SMS1) was constructed by insertionally inactivating ftpA. 35000HP-SMS1 did not express FtpA and was nonpiliated but was otherwise identical to its parent, 35000HP. Seven healthy adults were challenged on the upper arm with the isogenic isolates in a double-blinded, escalating dose-response study. Sites inoculated with the mutant produced papules and pustules at rates similar to the rates observed at sites inoculated with the parent. The recovery rate of H. ducreyi from cultures and the histopathology of biopsy samples obtained from pustules inoculated with 35000HP or 35000HP-SMS1 were similar. Although pili are expressed in vivo, FtpA is not required for pustule formation in the human challenge model.