[Seborrheic keratoses studied using scanning electron microscopy]

Ten seborrheic keratosis of acanthotic type have been observed by S.E.M. The morphological study could confirm the existence of two processes in the origin of the horny cysts which are peculiar to this affection. a) an extrafollicular process causes the involvement of groups of keratinocytes which, by assuming a vortex disposition, produce a concentric keratinization; b) a follicular process which causes an accentuated keratinization of the cells surrounding the epithelial sheath. This process was associated to the presence of multiple hairs a single follicle. Moreover, with higher magnification, it was possible to observe a great number of bacteria, yeasts and of particular alteration of the membrane which could be compared to changes in the tone filaments.

Kaposi's sarcoma in kidney transplant recipients treated with cyclosporin

We report the clinical and histological features and the course of Kaposi's sarcoma in three transplant patients treated with cyclosporin. Four months after cyclosporin treatment was stopped the lesions in all three patients had completely healed.

Self-healing pseudoangiosarcoma. Unusual vascular proliferation resembling a vascular malignancy of the skin

Pseudomalignant vascular lesions are increasingly recognized by dermatologists and may be present in several disorders affecting vessels. We describe a 58-year-old obese woman who developed vascular papulonodular lesions in the left inguinocrural area, clinically and histologically resembling a malignant vascular proliferation, that spontaneously regressed within a few months, after bed rest and weight reduction. Therefore, our patient's vascular lesions appear to have been pseudomalignancies. There are no other similar conditions reported in the literature. This kind of disorder demonstrates that vascular tissue can be involved in very bizarre cell and tissue reactions to several stimuli and can mimic malignant neoplasms. We stress the importance of constant surveillance of this kind of lesion to collect adequate clinical data, because histologic findings alone may cause misdiagnosis and lead to treatment hazardous to the patient.

Porokeratosis: immunosuppression and exposure to sunlight

Four cases of disseminated superficial actinic porokeratosis are described, all in patients who had been given immunosuppressive treatment, which might have been a contributing factor in the development of the condition. The possible relationship of immunosuppressive actinic porokeratosis to viral infection is also discussed.

Cutaneous lesions in 67 cyclosporin-treated renal transplant recipients

Sixty-seven out of 100 kidney transplant recipients treated with cyclosporin and methylprednisolone were evaluated for the presence of dermatological manifestations. Only 2 patients had no dermatological lesions; 80% had iatrogenic lesions, 38% infectious, 13% miscellaneous, 3% cancerous lesions, while 28% had cutaneous manifestations related to previous uremic state. Most of the lesions concerned the pilosebaceous unit: hypertrichosis (60%), epidermal cysts (28%), pilar keratosis (21%), acne (15%), folliculitis (12%) and sebaceous hyperplasia (10%). Among infectious manifestations, viral lesions were the most frequent and were very severe in the first month after transplantation. Two patients developed a squamous-cell epithelioma and a probable cutaneous lymphoma, respectively.