Necrotizing vasculitis within cutaneous lesions of mycosis fungoides

Mycosis fungoides is a T cell lymphoma with a predilection for cutaneous involvement. This paper describes the clinical manifestations and histopathologic features of a case of mycosis fungoides with necrotizing vasculitis localized to the lesions of cutaneous lymphoma. Elevated levels of circulating immune complexes were found in this patient. The large numbers of perivascular malignant helper T lymphocytes may have induced immunoglobulin synthesis, resulting in the formation of these complexes followed by deposition in vessel walls and subsequent necrotizing vasculitis. Possible alternative mechanisms include the presence of anti-T cell antibodies, or cytotoxic effector cells.     

Does biopsy type influence survival in clinical Stage I cutaneous melanoma?

A total of 472 patients with clinical Stage I cutaneous melanoma were analyzed to determine influence of type of diagnostic biopsy on survival. Of these patients, 119 had had an incisional biopsy (either punch or incision) and 353 had an excisional biopsy. Patients were grouped by thickness category and outcome compared between the biopsy types. Within each thickness category, there is no statistically significant difference in survival between the two groups. The observation that none of the seventy-six patients with primary tumors less than 1.70 mm have died following incisional biopsy strongly argues against any deleterious effect of incisional biopsy in this group. Alternatively, if the two highest-risk groups (greater than or equal to 1.70 mm) are analyzed as a single group, an adverse effect is seen in the incisional biopsy group (p less than 0.05). However, when the data from these groups are subjected to multivariate analysis, biopsy type is not a significant factor in the model. This study shows that either biopsy method may be used in first evaluating patients with suspected melanoma.     

Piroxicam-induced photosensitivity. In vivo and in vitro studies of its photosensitizing potential

A 36-year-old woman developed a photolocalized erythematous papulovesicular eruption while taking piroxicam. Histologic study revealed a superficial and deep spongiotic dermatitis. Phototesting with ultraviolet B (UVB) and ultraviolet A (UVA) was abnormal at the time the patient was seen and after oral challenge with the drug for 5 days. A modified lymphocyte transformation test was positive. The photosensitizing potential of the drug was evaluated in vivo and in vitro. In vivo studies consisted of phototesting twelve medical students before and after intake of piroxicam during 5 consecutive days. No lowering of the minimal erythema dose (MED) values or abnormal reactions to UV and visible light were observed in these students. In vitro studies by the Candida plate method and by photohemolysis showed negative results. Our studies suggest a systemic photoallergy mechanism requiring wavelengths in the UVA range for the reaction. This drug should be avoided in patients receiving photochemotherapy.     

Bilateral comparison of generalized lichen planus treated with psoralens and ultraviolet A

Ten patients with generalized lichen planus were treated with oral 8-methoxypsoralen photochemotherapy (PUVA) in a bilateral comparison study. Five patients (50%) cleared completely on both sides and required no maintenance treatment after a follow-up of up to 4 years. Three other patients (30%) improved at least 50% of their previous involvement. Most of the patients experienced symptomatic improvement of the treated side by the second week of the treatment. Two patients reacted adversely and exacerbated while receiving treatment to one side of the body. While preliminary, this bilateral comparison study demonstrates that PUVA is an effective therapy for generalized, symptomatic lichen planus and suggests that maintenance therapy might not be required once complete clearance is attained. Caution should be exercised, however, since some patients might develop an exacerbation of their disease with PUVA.     

Methotrexate-induced necrolysis

A 72-year-old woman with a long history of recalcitrant psoriasis developed severe generalized erosions after receiving low-dose (7.5 mg) methotrexate. Her clinical picture was consistent with toxic epidermal necrolysis and showed a gradual response to systemic steroids and topical therapy. Patients with underlying dermatoses or previous cutaneous insults may be particularly prone to adverse cutaneous reactions resulting from folic acid antagonists.     

Comparison of stratum corneum thickness in children and adults

We compared the thickness of the stratum corneum from abdominal skin in infants less than 3 months of age, children between 3 months and 11 years, and adults. Measurements were made with a filar micrometer eyepiece on histologic sections obtained at autopsy. No significant differences were seen; therefore, a stratum corneum of different thickness cannot be used to explain differences in percutaneous absorption, supporting previous work which suggested that term infants and children have an efficient skin barrier. The greater toxicity from percutaneous absorption of topical compounds sometimes seen in children is more likely due to their increased surface to volume ratio and/or metabolic differences.     

A stain for plucked anagen hairs.

Anagen and telogen plucked hairs may be difficult to distinguish based on their microscopic appearance. The root ends of plucked anagen hairs develop a red color when stained with 4-dimethylaminocinnamaldehyde, while those of plucked telogen hairs do not. This is the result of a reaction with citrulline-containing proteins in the internal root sheath. This histochemical stain provides a simple and accurate means of determining the telogen/anagen ratio in plucked hairs.     

Vascular abnormalities in lichen aureus

Lichen aureus is an infrequently reported subset of the pigmented purpuric dermatoses. A review of the English literature suggests the golden to purple colored lesions are asymptomatic or mildly pruritic with no regression once established. A case report of a 56-year-old man with lichen aureus of the thighs is presented. This case is unusual in that the patient had persistent pain at the lesion site. Furthermore, increased capillary fragility and koebnerization were both demonstrated. Treatment of an asymptomatic urinary tract infection resulted in temporary subjective and objective improvement.     

Observations on drug-induced toxic epidermal necrolysis in Singapore

Fifteen patients with toxic epidermal necrolysis (TEN) were studied. In all of them the TEN was related to drug ingestion and believed to be drug-induced. The drugs implicated include pyrazolone derivatives, allopurinol, barbiturates, tetracycline, phenytoin, and penicillamine. Possible etiologic co-factors are infections, cancer, and the systemic lupus erythematosus diathesis. The extent of skin loss varied from 25% to almost 100% involvement of the total body surface. Seven of the fifteen patients had more than 75% epidermal loss. Three deaths were recorded (20%). From observations on these fifteen patients it was found that a single drug can cause two "reaction" patterns, namely, Stevens-Johnson syndrome (or erythema multiforme) and TEN, at the same time or at different times in one and the same patient. It is stressed that from the prognostic and therapeutic viewpoints patients with TEN may be equated to patients with extensive partial-thickness burns and should be treated in a burn unit.     

Pseudomonic acid, a new antibiotic for topical therapy

Pseudomonic acid, a new wide-spectrum antimicrobial agent, was evaluated as a 2% formulation in a cream. Animal studies showed that this formulation was just capable of penetrating the skin. When administered parenterally to animals, pseudomonic acid was converted to inactive metabolites that were quickly eliminated from the body. When pseudomonic acid was applied as a cream to human skin, no sensitization was observed. In an open clinical study, sixty-eight patients with skin infections (mostly superficial conditions such as impetigo, infected eczema, folliculitis, or balanitis) applied pseudomonic acid cream three times a day for 5 days. In fifty patients the infections completely cleared within 2 days of the end of therapy, and considerable clinical improvement was noted in sixteen more. One patient stopped the treatment prematurely due to local burning pain, and one patient could not be evaluated clinically.