[Pattern analysis of inflammatory skin diseases according to A. B. Ackerman-always up to date]

The exact microscopic diagnosis of inflammatory skin diseases requires the linking of histopathological findings with clinical features. This is not easy when skin biopsies are rarely assessed and the terminology of dermatopathology and dermatology is itself unfamiliar.The infiltrates of almost all inflammatory skin diseases tend to show eight specific patterns in high magnification. By further classifying according to architectural and cytological features, a specific diagnosis can be made in most cases. At the same time, clinically suspected diagnoses are simply excluded or greatly reduced in number. This procedure, starting with the overview magnification and the recognition of clearly defined histomorphological features, corresponds to an algorithm.Another algorithmic approach uses histomorphological changes under high magnification. Here, "nonspecific" findings are added to the pattern analysis as a diagnostic vehicle.Occasionally, inflammatory skin diseases cannot be assessed conclusively with current modern methods. Such pathology reports should be written descriptively and possible differential diagnoses should be mentioned as notes. The report should be written in a language understandable to the clinician.Artificial intelligence, with its ability to transform and integrate extensive clinical as well as image data, will play an important role in the future of decision making, diagnosing, and personalizing medicine. In the field of pathology, it could be seen as a second opinion. It is important that physicians always contribute their opinion where important algorithmic decisions are made, such as in algorithm design, data quality, interpretation, action, and feedback.

Fumarate hydratase immunohistochemical staining may help to identify patients with multiple cutaneous and uterine leiomyomatosis (MCUL) and hereditary leiomyomatosis and renal cell cancer (HLRCC) syndrome

AIMS

Multiple cutaneous and uterine leiomyomatosis (MCUL) also named as hereditary leiomyomatosis and renal cancer syndrome (HLRCC) is an autosomal dominant disorder caused by heterozygotic germline mutations in fumarate hydratase (FH) with incomplete penetrance and clinically challenging to diagnose. To test immunohistochemistry for FH as a potential marker for the detection of FH-deficiency.

METHODS AND RESULTS

We have tested 42 smooth muscle neoplasms, 13 lesions of patients with suspicious or confirmed HLRCC, 20 sporadic piloleiomyomas, two angioleiomyomas and 7 leiomyosarcomas. FH staining grades from 1 to 3. Ten of the 13 lesions from the patients with HLRCC syndrome showed negative FH staining. Most sporadic piloleiomyomas presented grade 3 FH staining although five cases presented grade 1 FH staining. Sensitivity of FH staining in our series is 83.3% but specificity is 75%.

CONCLUSIONS

This staining could indicate a high risk of HLRCC in most of the confirmed cases but it could also suggest the presence of a syndrome in up to 25% of sporadic cases. HLRCC syndrome should be rule out in FH negative piloleiomyomas after complete anamnesis if multiple lesions or positive familiar history is found.

["Dangerous" cutaneous polyp. Exophytic cutaneous myxofibrosarcoma]

Malignant skin tumors are seldom polypoid lesions. Thus lesions presenting as large skin tags, as in this case, may initially not be recognized and treated as a malignancy. Often such protuberant lesions are removed by shave biopsy. Then, as in this case, the clinician is very surprised to receive the diagnosis of myxofibrosarcoma (MFS). This case shows how important it is to further investigate a common tumor, like a large skin tag, when its clinical appearance is unusual. Myxofibrosarcoma or myxoid malignant fibrous histiocytoma is one of the common, perhaps most common, sarcoma in adults. Clinical presentation as a large skin tag is extremely uncommon. The rapid growth of the polypoid sarcoma indicates the need for completely operative removal. The behavior of the MFS depends on the degree of malignancy, depending on the tumor size, depth of penetration and local control. While smaller dermal or subcutaneous localized MFS hold potentially a risk of recurrence, do larger examples with a high tumor grade and seated in the deep soft tissue posses a variable metastatic potential. Despite large variability of cell number, cellular atypia and the numbers of mitotic figures all myxofibrosarcoma have in common the multinodular structure with incomplete septa, the mucinous stroma and curvilinear fine vessels.

Basic concepts in skin biopsy. Part I

The aim of these reviews is to describe the reasons for performing skin biopsy, to provide indications for the choice of area to be biopsied and the preparation of the sample, and to summarize the various complications of dermatologic surgery. In addition, we present a guide for selecting the biopsy technique based on the suspected diagnosis and on the area to be biopsied. Finally, the various artifacts that can complicate interpretation of results are described, together with the methods used to prevent their appearance insofar as is possible. The aim of this guide is to improve the diagnostic yield of biopsies and to highlight the importance of a correct clinical-histological correlation.

FISH analysis for diagnostic evaluation of challenging melanocytic lesions

The differential diagnosis of malignant melanomas and atypical melanocytic nevi is still a diagnostic challenge. The currently accepted morphologic criteria show substantial interobserver variability, likewise immunohistochemical studies are often not able to discriminate these lesions reliably. Techniques that support diagnostic accuracy are of the greatest importance considering the growing incidence of malignant melanomas and their increase in younger patients. In this study we analyzed the feasibility of fluorescence in situ hybridization (FISH) analysis for the discrimination of malignant and benign melanocytic tumors. A panel of DNA probes was used to detect chromosomal aberrations of chromosomes 6 and 11. On a series of 5 clearly malignant and benign melanocytic tumors we confirmed the applicability of the test. Then we focused on examination of ambiguous melanocytic lesions, where atypical cells are often difficult to relocalize in the 4',6-Diamidino-2-phenylindol (DAPI)-fluorescence stain. FISH analyses were conducted on destained H&E-stained slides. By comparison of the DAPI-image with photos taken from the H&E stain, unambiguous assignment of the FISH results to the conspicuous groups of cells was possible. The results of FISH analysis were consistent with the conventional diagnosis in 11 of 14 small ambiguous lesions. Of the remaining 3 cases, 2 showed FISH-results close to the cut-off level. Comparison of FISH results on thin and thick sections revealed that the cut-off values have to be adapted for 2 microm destained sections. In conclusion, FISH analysis is a useful and applicable tool for assessment of even smallest melanocytic neoplasms, although there will remain unclear cases that cannot be solved even after additional FISH evaluation.

Short incubation with methyl aminolevulinate for photodynamic therapy of actinic keratoses

BACKGROUND

Photodynamic therapy (PDT) using methyl aminolevulinate (MAL) is an effective first-line treatment for actinic keratoses. A reduced incubation period may have practical advantages.

OBJECTIVE

This study aims to evaluate the effect of incubation time (1 vs. 3 h), MAL concentration (160 mg/g vs. 80 mg/g) and lesion preparation in the setting of MAL-PDT for treatment of actinic keratosis (AK).

DESIGN

Open, randomized, parallel-group multicentre study.

SETTING

Outpatient dermatology clinics.

SUBJECTS

One hundred and twelve patients with 384 previously untreated AK. Most lesions (87%) were located on the face and scalp and were thin (55%) or moderately thick (34%).

METHODS

Lesions were debrided, and MAL cream (160 mg/g or 80 mg/g) was applied before illumination with red light (570-670 nm; light dose, 75 J/cm2). Patients were followed up at 2 and 3 months. Sixty patients (54%) were re-treated and assessed at 6 months.

MAIN OUTCOME

Complete lesion response rates 3 and 12 months after last treatment.

RESULTS

For lesions on the face/scalp, lesion complete response rates were 78% for thin AK and 74% for moderately thick AK lesions after 1 h vs. 96% and 87% after 3 h incubation with MAL 160 mg/g. Lesion recurrence rates at 12 months after two treatments were similar [19% (3 of 16) with 1 h vs. 17% (3 of 18) with 3 h 160 mg/kg MAL-PDT] and lower than for 80 mg/g MAL-PDT (44-45%).

CONCLUSION

MAL-PDT using a 1-h incubation may be sufficient for successful treatment of selected AK lesions.

[Regression in malignant melanoma. Definition, etiopathogenesis, morphology and differential diagnosis]

Malignant melanoma is a neoplasm that more often tends to undergo regression. Clinically, variation in color is perhaps the most important hallmark of primary cutaneous melanoma. The change in color to white, off-white, blue-white and gray-white is a sign of (spontaneous) regression in malignant melanoma. Histopathologically the process starts with a dense lichenoid infiltrate of lymphocytes, and ends with fibrosis and/or melanosis within a thickened papillary dermis. The dense infiltrate of lymphocytes permeates the thin melanoma and destroys the atypical melanocytes in the epidermis and the papillary dermis. A key concern is how to define regression in a reproducible way. Using the following definition, a statistically significant risk of metastases can be demonstrated in thin melanomas (<1.0 mm) with extensive regression (>50%): "fibroplasia with an absence of epidermal and dermal involvement by melanoma cells, but allowing for (lentiginous) single-cell proliferation of atypical melanocytes along the dermo-epidermal junction".

[Nasal polyps and osteolyses]

A 38-year-old man presented with a 2-month history of progressive leg pain. An x-ray film of both tibial bones showed multiple osteolysis. At the same time, nasal polyps were present. A biopsy of the tibial bone remained unclear. A carcinoma was not found. A biopsy of the nasal polyps revealed a Rosai-Dorfman-Destombes disease.

Acute generalized exanthematic pustulosis (AGEP) in a patient treated with furosemide

BACKGROUND

Although they appear more rarely than electrolyte disturbances, cutaneous reactions are important adverse effects of furosemide. This is particularly true for bullous skin eruptions, because they may be life-threatening.

CASE REPORT

We describe a patient who developed acute generalized exanthematic pustulosis (AGEP) during treatment with furosemide. Because the patient had developed similar skin eruptions during treatment with furosemide years before, furosemide was considered the most likely cause of this reaction. The short period of time between exposure to furosemide and the appearance of the skin reaction, as well as a positive lymphocyte transformation test, suggest an immunological mechanism of the skin disease.

CONCLUSION

AGEP is a possible cutaneous side effect of furosemide.

Primary cutaneous cryptococcosis in a patient with systemic immunosuppression after liver transplantation

We report a 36-year-old woman who slowly developed an ulceration on the left thigh 2 years after transplantation for Budd-Chiari syndrome. At this time point, the patient was treated with prednisone, tacrolimus and azathioprine for immunosuppression and with phenprocoumon and low-dose aspirin for anticoagulation in the presence of polycythemia vera. A biopsy of the skin lesion was obtained and revealed encapsulated yeast that was identified by microbiological and serological methods as Cryptococcus neoformans serotype D. The patient had no signs of systemic infection and a therapy with fluconazole (200 mg/day) was started. The lesion healed within 8 weeks and fluconazole was stopped after 3 months. Due to interactions between fluconazole, tacrolimus and phenprocoumon, the latter drugs were decreased to prevent toxicity. So far, 1 month after stopping fluconazole, no recurrence of skin lesions has been observed.

Typical features of calciphylaxis in a patient with end-stage renal failure, diabetes mellitus and oral anticoagulation

We report a multimorbid patient with end-stage renal failure showing a large necrosis and livedo racemosa on the right thigh. Histology revealed medial calcification of the small arteries typical of calciphylaxis. We found the typical features of the disease with different risk factors like elevated calcium-phosphate product, diabetes mellitus and oral anticoagulation. On account of the location of the skin lesions, a bad prognosis was expected. In spite of therapeutical measures with lowering of the calcium and phosphate levels, the patient died 1 month after the diagnosis had been made.

Cutaneous nocardiosis caused by Nocardia brasiliensis after an insect bite

We report the case of a primary lymphocutaneous nocardiosis occurring on the right calf of a healthy 56-year-old man after an insect bite. Analysis of the purulent exudate obtained from the nodule revealed Nocardia brasiliensis. The initial therapy with trimethoprim-sulfamethoxazole had to be stopped due to a drug eruption. However, with minocycline treatment the patient recovered within 5 weeks. Superficial (sporotrichoid) infections and a history of outdoor injury should be considered suspicious for cutaneous nocardiosis.

[Transitory acantholytic dermatosis (Grover disease). An analysis of the clinical spectrum based on 21 histologically assessed cases]

BACKGROUND AND OBJECTIVE

In 1970 Ralph W. Grover described a clinicopathologic entity characterized by pruritic keratotic papules and papulovesicles predominantly on the trunk, disappearing spontaneously after a few weeks or months and demonstrating the histological features of epidermal acantholysis. The etiology remains unknown; sweating, heat and sunlight are suspected trigger factors. In our survey the clinical spectrum of the disease will be examined.

PATIENTS AND METHODS

We have analyzed 21 cases of Grover's disease histologically diagnosed in Berne in 1997 and 1998.

RESULTS

In most cases we observed isolated papules disseminated on the trunk. The predominant histological type was the Darier-type; presumably there is no correlation between histological type and clinical features. At the time of diagnosis the skin disorder had been present on average for 83 months. There was a strong association with sweating and heat. Topical steroids were successful in 50% of patients.

CONCLUSIONS

Our 21 cases reflect in general the literature. Nevertheless, the long persistence of the skin lesions was striking perhaps making the term transient somewhat inaccurate.

[Photo-aging]

Photodamage starts early in childhood due to repeated and unprotected sun exposure. It is observed almost exclusively in individuals with white skin, especially skin phototypes I and II. Clinical studies show that 50 to 80% of an individual's life time ultraviolet (uv) radiation occurs before the age of 18 years. Photodamage, also known as dermatoheliosis, represents a polymorphic alteration of several structures of the skin, especially keratinocytes and melanocytes in the epidermis, the vascular system, and the dermal connective tissue. This damages caused by acute and chronic uv-exposure result in a substantially increased incidence of skin cancers. The severity of photodamages depends on constitual factors, e.g. skin phototype (skin color, capacity to tan), and on duration as well as intensity of sun exposure. Tanning for cosmetic purposes by sunbathing or by using artificial tanning devices is still widespread. Thus, it is important that clinicians are familiar with the clinical manifestations of photodamages and skin cancer. Further efforts to educate both public and medical professions are essential to direct more patients earlier to treatment. Furthermore new strategies need to be developed to influence behaviour as well as to increase awareness.