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Helmut Kerl

Publications and source records attributed to Helmut Kerl.

At least 55 records · Page 3Linked to original sources
PubMed2005

Digital image enhancement for in vivo laser scanning microscopy.

BACKGROUND/PURPOSE: In vivo confocal laser scanning microscopy (CLSM) is a new method that provides skin images in horizontal plane at a level of resolution that allows to view microanatomic structures. This study examines whether certain digital image-processing steps can increase the visibility of various structures in CLSM. STUDY DESIGN: Fifty images were taken from normal skin of 25 probands, and 39 image enhancement procedures were created. Eight procedures that seemed to provide some quality enhancement were deliberately selected for further evaluation. Subsequently, a collection of random pairs of the original image and an image submitted to any of the eight selected procedures was rated by five independent observers. RESULTS: In three of the eight procedures tested, the modified image was significantly preferred to the original image (chi2-test,: P< or =0.001). In particular, smoothing, shading correction, delineate and grey-level normalization in various combinations were helpful in showing the characteristic honeycomb pattern, pigmented basal cell layer, cell borders and the nuclei more clearly. CONCLUSION: Digital image processing may help to increase visibility of in vivo CLSM images.

Adolescent↗
PubMed2005

[Computer-based training in dermatooncology--a preliminary report comparing electronic learning programs with face-to-face teaching].

BACKGROUND: Electronic media are increasingly used in medical education. The question arises whether tutorial programs are as effective as innovative face-to-face didactic formats. METHODS: 26 students underwent a special dermatooncology course in an integrated undergraduate medical curriculum. One part of the content was acquired face-to-face with emphasis on team learning and mini-lectures; the other part was presented as web-based electronic computer-based training objects. The performance of the students in a subsequent multiple choice test was evaluated. RESULTS: In total, questions referring to computer-based training contents were answered correctly in 90.4 +/- 12.5 %, which was significantly superior to the questions referring to team learning in the face-to-face teaching format (80.6 +/- 13.1 %; p < 0.001). There was, however, a significant correlation between both results for each individual student (r = 0.52; p < 0.01), but there was no correlation between the results obtained for computer-based training or team learning on the one hand, and the overall performance of the individual student on the other. CONCLUSIONS: Though different contents were concerned, our study provides evidence that computer-based training may be more efficient than face-to-face teaching using team learning to communicate dermatooncology contents in an undergraduate medical curriculum.

Austria↗
PubMed2005

Wound teleconsultation in patients with chronic leg ulcers.

BACKGROUND: The treatment of chronic leg ulcers requires frequent assessments of local wound status and adjustment of therapy. The availability of reasonably priced photographic equipment and quick electronic transfer of high-quality digital images should make it possible that the assessment of wound status can be made by remote experts. OBJECTIVE: This study examines the feasibility of using teledermatology for wound assessment and therapeutic suggestions for patients with chronic leg ulcers. METHODS: One hundred ten chronic leg ulcers of different origins were examined in face-to-face consultations. The examining doctor assessed the wound, made therapeutic recommendations and took 1-4 photographs of the wound using a digital camera. The digital images and relevant clinical information were then transmitted via a web application to an expert in wound care, who provided an independent teledermatological assessment of wound status and therapeutic recommendations. RESULTS: In our study, a high accordance between direct consultations and electronic consultations was found in the assessment of chronic leg ulcers, especially for important features like slough (concordance: 84.6%), necrosis (concordance: 98.2%) and granulation tissue formation (concordance: 76.4%). Furthermore, the teledermatologist generally felt confident in recommending further treatment strategies and in planning further wound assessments via the internet. CONCLUSIONS: Our results suggest that teledermatology offers great potential for the future in chronic wound care. By reducing the need to travel long distances to the hospital or to consult a physician with expertise in wound care, wound teleconsultation might lower health care costs and improve the quality of life for patients with chronic wounds, while still maintaining a high quality of wound care.

Adult↗
PubMed2004

Increased prevalence of human papillomavirus in hairs plucked from patients with psoriasis treated with psoralen-UV-A.

BACKGROUND: Patients with psoriasis treated with psoralen-UV-A (PUVA) are at increased risk of skin cancer; however, the exact causes of this increased incidence are not well understood. It has been suggested that PUVA may increase expression of the tumorigenic agent human papillomavirus (HPV) in skin by directly stimulating virus replication, immune suppression, or both, thereby leading to skin cancer formation. OBJECTIVE: To determine whether HPV DNA prevalence in the skin is increased after long-term PUVA treatment. DESIGN: Screening for the presence of HPV sequences in DNA isolated from plucked body hairs of patients with psoriasis with a history of PUVA exposure and a history of skin cancer (group A), PUVA exposure and no history of skin cancer (group B), and no PUVA exposure and no history of skin cancer (group C). SETTING: University hospital. PATIENTS AND METHODS: Hair samples were obtained from 81 patients with psoriasis (56 men and 25 women; mean age, 52 years), including 16 in group A (mean number of PUVA exposures, 702), 35 in group B (mean number of PUVA exposures, 282), and 30 in group C. DNA was isolated from the hair samples and analyzed by polymerase chain reaction with the use of 2 nested primer systems specific for epidermodysplasia verruciformis-associated or related and genital or mucosal virus types, respectively. RESULTS: The rate of HPV DNA positivity was significantly higher in groups A (73% [11/15]) and B (69% [24/35]) than in group C (36% [10/28]) (A + B vs C, P =.009; chi(2) test; age adjusted). Conclusion The prevalence of HPV in the skin (hair follicles) is increased in patients with psoriasis who have a history of PUVA exposure.

Adult↗
PubMed2004

Lymphomatoid papulosis: reappraisal of clinicopathologic presentation and classification into subtypes A, B, and C.

OBJECTIVES: To analyze clinicopathologic features of lymphomatoid papulosis and delineate the characteristics of histopathologic variants (types A, B, and C). DESIGN: Retrospective nonrandomized study. SETTING: University-based dermatologic referral center. PATIENTS: Eighty-five patients with lymphomatoid papulosis. Clinical data and 1 or more biopsy specimens were available for review in all cases. When possible, immunophenotypic and molecular analyses were carried out. RESULTS: Of these patients, 78 presented only 1 histopathologic subtype of lymphomatoid papulosis (64 had type A, 3 had type B, and 11 had type C). The last 7 patients presented more than 1 subtype (1 had A and B, 5 had A and C, and 1 had A, B, and C). Two patients had regional lymphomatoid papulosis, an unusual clinical presentation characterized by groups of lesions localized to 1 anatomic region. We observed, we believe for the first time, that some histopathologic patterns, ie, follicular mucinosis (n = 1), syringotropic infiltrates (n = 1), epidermal vesicle formation (n = 2), and syringosquamous metaplasia (n = 1), were associated with lymphomatoid papulosis. A distribution along hair follicles, or follicular lymphomatoid papulosis, was observed in 5 biopsy specimens. A bandlike rather than a wedge distribution of the infiltrate was seen in 5 specimens from patients with lymphomatoid papulosis type A. Of 8 patients who had associated lymphoid malignancies, 4 had Hodgkin disease and 4 had mycosis fungoides. CONCLUSIONS: Lymphomatoid papulosis is a cutaneous disorder with multiple clinicopathologic features. Differentiating between mycosis fungoides and anaplastic large cell lymphoma may be very difficult and sometimes impossible. In the spectrum of CD30(+) cutaneous lymphoproliferative disorders, boundaries between these 2 entities are not clear-cut.

Adult↗
PubMed2004

Genital lentigines and melanocytic nevi with superimposed lichen sclerosus: a diagnostic challenge.

BACKGROUND: Benign pigmented lesions of the genitalia, such as genital lentigines and melanocytic nevi, often show clinical and histopathologic features highly suggestive of malignant melanoma (MM). Superimposed changes of lichen sclerosus (LS) may cause real concern and lead to an erroneous diagnosis of MM. OBJECTIVE: This study was performed to assess clinicopathologic characteristics of genital lentigines and melanocytic nevi with associated LS. METHODS: We performed a retrospective review of 5 cases. RESULTS: Histopathologic sections of the 2 cases of genital lentigines with concurrent changes of LS showed a lichenoid lymphocytic infiltrate and pigment incontinence with melanophages in a fibrosed papillary dermis, features reminiscent of completely regressed MM. The 3 cases of genital melanocytic nevi and superimposed LS were sharply circumscribed, relatively symmetric, but revealed confluent nests varying in size and shape and pagetoid upward spread of melanocytic nests and single melanocytes. Changes of LS extended beyond the melanocytic proliferation. CONCLUSION: Genital lentigines and melanocytic nevi with associated LS may show features that mimic MM.

Adult↗
PubMed2004

Reduction of treatment frequency and UVA dose does not substantially compromise the antipsoriatic effect of oral psoralen-UVA.

BACKGROUND: The carcinogenic potential of 8-methoxypsoralen photochemotherapy (psoralen-UVA [PUVA]) is correlated with the total number of treatments and cumulative UVA dose applied during oral PUVA therapy. OBJECTIVE: We sought to determine whether reducing treatment frequency and UVA dose affects the therapeutic efficacy of oral PUVA for patients with chronic plaque psoriasis. METHODS: This was a prospective, randomized, half-side study performed in a photodermatology department in a dermatology hospital. Eighteen consecutive patients with chronic plaque psoriasis received paired PUVA regimens (0.5 minimal phototoxic dose [MPD] 4 times/wk vs 1 MPD twice/wk, 0.5 MPD twice/wk vs 1 MPD twice/wk, and 0.5 MPD twice/wk vs 0.75 MPD twice/wk). The PUVA regimens were assessed for reduction of Psoriasis Area and Severity Index (PASI) score and the number of treatments and cumulative UVA dose required to reduce PASI score to defined end points (ie, PASI reductions of 25%, 50%, and 75%) or to induce complete remission (PASI < 3). RESULTS: Reducing the number of treatments while maintaining the same UVA dose per week did not reduce overall therapeutic efficacy. Reducing the number of treatments to twice a week and reducing the UVA dose from 1 MPD to 0.75 or 0.5 MPD per treatment only slightly affected intermediate therapeutic efficacy (between the second and seventh weeks of therapy) but had no effect on final clearance rates. The time to complete clearance did not significantly differ between regimens. The mean cumulative UVA dose was significantly lower for the least intensive dose regimen (0.5 MPD twice/wk) than for the more intensive regimens. CONCLUSIONS: Reducing treatment frequency and UVA dose does not substantially compromise the therapeutic efficacy of PUVA.

Administration, Oral↗
PubMed2004

Diagnostic principles and new developments in primary cutaneous B-cell lymphomas.

The most common subtypes of primary cutaneous B-cell lymphomas are marginal zone B-cell lymphoma/immunocytoma, follicle center cell lymphoma, and large B-cell lymphoma of the leg. Precise classification (European Organization for Research and Treatment of Cancer (EORTC) scheme) can be achieved only after a complete synthesis of clinical, histopathological, immunophenotypic, and molecular features. It is extremely important to emphasize that primary cutaneous B-cell lymphomas differ significantly from their nodal counterparts and are frequently characterized by an excellent prognosis. Awareness of this special clinical behavior should prevent the application of unnecessarily aggressive treatment protocols. Future definitions of primary cutaneous B-cell lymphomas will be based on their etiology and pathogenesis and especially on their molecular features. Some important areas are presented where exciting findings have been detected.

Humans↗
PubMed2004

UV light-induced linear IgA dermatosis.

Various exogenous factors (eg, drugs, dietary antigens, trauma, infections, radiographs, and UV radiation) are known to induce or aggravate skin diseases. UV radiation in particular is known to induce or aggravate the autoimmune bullous diseases of pemphigus foliaceus, pemphigus vulgaris, and bullous pemphigoid. Its role in linear IgA dermatosis, however, is not well recognized. We report the second case of linear IgA dermatosis induced by intense sun exposure in which blistering was induced by UVA radiation. Furthermore, a review of the literature on photoinduced autoimmune bullous diseases and the wavelengths responsible for the induction of blistering is presented and several proposed mechanisms of action for the blister induction, including release or unmasking of antigens, promotion of antibody fixation by UV radiation, and launching of an inflammatory process, are discussed. We conclude that linear IgA dermatosis should be added to the list of autoimmune bullous diseases induced and/or aggravated by UV radiation.

Aged↗
PubMed2004

The ultraviolet fingerprint dominates the mutational spectrum of the p53 and Ha-ras genes in psoralen + ultraviolet A keratoses from psoriasis patients.

Psoriasis patients exposed to high cumulative doses of psoralen + ultraviolet A frequently exhibit so-called "psoralen + ultraviolet A keratoses" (i.e., hyperkeratotic lesions with varying degrees of histologic atypia). The exact causes and molecular mechanisms of psoralen + ultraviolet A keratoses however, are not clear. We therefore performed DNA mutational analysis of the tumor suppressor gene p53 (exons in psoralen + ultraviolet A keratoses from 10 long-term psoralen + ultraviolet A-treated psoriasis patients. We detected 39 p53 mutations in 16 of 28 psoralen + ultraviolet A keratoses (57%) and 18 Ha-ras mutations in 11 of 25 psoralen + ultraviolet A keratoses (44%). Of the 39 p53 mutations and 18 Ha-ras mutations, 22 (56%) and 13 (72%), respectively, were of the ultraviolet fingerprint type (C-->T or CC-->TT transitions at dipyrimidine sites); 13 (33%) and two (11%), respectively, occurred at potential psoralen-binding sites (5'-TpA, 5'-TpG, or 5'-TpT DNA sequences) and were potentially psoralen + ultraviolet A induced; two (5%) and three (17%), respectively, were of ambiguous origin (ultraviolet and/or psoralen + ultraviolet A); and two (5%) and none (0%), respectively, were of the "other" type, respectively. We conclude that (1) the frequent mutation of p53 and Ha-ras may play a key part in the formation of at least some psoralen + ultraviolet A keratoses; (2) environmental and/or therapeutic ultraviolet exposure may be a major cause of psoralen + ultraviolet A keratosis as most Ha-ras and p53 mutations are induced by ultraviolet light; and (3) psoralen + ultraviolet A itself plays a smaller, though direct, role in causing these mutations.

Adult↗
PubMed2004

Differential diagnosis of cutaneous infiltrates of B lymphocytes with follicular growth pattern.

The differential diagnosis of cutaneous B-cell infiltrates with follicular pattern of growth is one of the most vexing problems in dermatopathology. In this study we focused on histopathologic, immunophenotypic, and molecular differential diagnostic criteria between Borrelia burgdorferi (Bb)-associated lymphocytoma cutis (LC), primary cutaneous follicle center cell lymphoma (FCCL), and primary cutaneous marginal zone lymphoma (MZL) with reactive germinal centers (GCs). A total of 47 patients were included in the study, including 12 cases of LC (M:F = 2:1; mean age: 38.0; median: 31; range: 9-75), 29 cases of FCCL (M:F = 1.2:1; mean age: 57.5; median: 57; range: 24-97), and 6 cases of MZL (M:F = 1:1; mean age: 63.8; median: 67.5; range: 38-86). In all cases complete phenotypic data were available. In addition, the IgH gene rearrangement and the t(14;18) were analyzed using the polymerase chain reaction technique (PCR) in 41 (FCCL = 27, LC = 10, MZL = 4) and 18 cases (FCCL = 15, LC = 2, MZL = 1), respectively. Histology revealed in all cases of FCCL one or more atypical feature of the follicles including the lack of or a reduced mantle zone, lack of polarization, tendency to confluence, and absence of tingible body macrophages. In most cases of Bb-associated LC, the GCs were devoid of mantle zone, lacked polarization, and revealed tendency to confluence as well, but all cases showed the presence of several tingible body macrophages. In MZL, follicles showed typical features of reactive GCs. Immunohistology revealed a reduced proliferative activity of neoplastic follicles as detected by MIB-1 antibody in 23 of 29 cases of FCCL (79.3%), but only in 1 case of LC (8.3%). Proliferation of the GCs was normal in all cases of MZL. Positivity for CD10 and/or Bcl-6 was found in small clusters outside the follicles in 19 cases of FCCL (65.5%), and in 3 cases of LC (25%), but in no case of MZL. The intensity of CD10 staining on follicular cells on average was stronger in cases of FCCL, but overlapping features could be observed. Finally, staining for Bcl-2 protein was consistently negative on GC cells in cases of LC and MZL, and was positive on a variable proportion of the cells in 8 cases of FCCL (28.6%). Molecular analyses showed no evidence of the t(14;18) in all cases tested. Analysis of the IgH gene rearrangement revealed a monoclonal pattern in 1 of 10 cases of LC (10%), 14 of 27 cases of FCCL (51.9%), and 2 of 4 cases of MZL (50%) tested. In summary, Bb-associated LC and FCCL show sometimes overlapping histopathologic, immunohistochemical, and molecular features, whereas follicles in MZL show clear-cut aspects of reactive GCs. Absence of tingible body macrophages within follicles, reduced proliferation of the follicles as detected by immunohistology, presence of positivity for Bcl-2 protein within follicular cells, and monoclonality by PCR are the main criteria suggestive of malignancy. Diagnosis of cutaneous infiltrates of B lymphocytes with follicular growth pattern should be achieved by integration of clinical data with histopathologic, immunohistochemical, and molecular features of the lesions.

Adolescent↗
PubMed2004

Melan-A: not a helpful marker in distinction between melanoma in situ on sun-damaged skin and pigmented actinic keratosis.

Pigmented actinic keratosis is one of the simulators of early melanoma in situ from severely sun-damaged skin. Close scrutiny of the hematoxylin and eosin stained section does not always allow an unequivocal diagnosis, because it is sometimes difficult to distinguish pigmented keratinocytes from melanocytes. Immunohistochemical stains, such as S-100 and HMB-45, are used routinely to address this problem. Melan-A, also known as MART-1, is an additional melanocytic marker and has proved to be useful in identifying metastatic tumors of melanocytic origin. The usefulness of this marker to discriminate pigmented actinic keratosis from early melanoma in situ, however, has not yet been a subject of investigation. In this study we evaluated Melan-A expression in ten unequivocal cases of pigmented actinic keratosis and compared the staining pattern with that of S-100, HMB-45, and tyrosinase. In all ten cases the number of cells highlighted with Melan-A was by far larger than those labeled with S-100, HMB-45, and tyrosinase. Four cases showed clusters of Melan-A positive cells being suggestive of melanocytic nests. Even areas of normal skin adjacent to the actinic keratosis featured prominent staining of Melan-A, but only inconsistent labeling of intraepidermal melanocytes with S-100, HMB-45, and tyrosinase. We therefore believe that Melan-A is a more sensitive marker for intraepidermal melanocytes than S-100, HMB-45, and tyrosinase. In addition there may be expression of Melan-A in keratinocytes and nonmelanocytic cells. To avoid an erroneous diagnosis of malignant melanoma one should therefore interpret results obtained from Melan-A stained slides carefully and in the context with other melanocytic markers.

Aged↗