No abstract

A case of giant pigmented tumour of the scalp which developed in a 47-year-old woman is reported. Macroscopically, the tumour showed a peculiar two-layered structure, consisting of an upper non-pigmented and a lower pigmented portion. Histologically, it was composed of elongated neurofibromatous tumour cells with abundant collagen fibres in the non-pigmented portion and round naevus-like cells with abundant melanin pigment in the pigmented portion. S-100 protein and neurone-specific enolase were demonstrated in most of the tumour cells, but neurofilament and myelin basic protein were not detected. Electron microscopy revealed melanosomes in the tumour cells of the pigmented portion. These findings might support a melanocytic origin for the tumour, but the lack of superficial pigmentation and the associated hair loss were against this. The tumour may represent an example of duality of neural crest differentiation.

Xanthoma was produced in diet-induced hypercholesterolemic rabbits by intradermal dextran sulfate injections. The serum cholesterol level returned to the normal range at about 10 weeks after ending the cholesterol diet. Gross observations after cessation of the cholesterol diet revealed a decrease in xanthomatous infiltrations. However, the dense foam cell infiltrations and cholesterol accumulations showed no signs of regression at even 9 months after ending the cholesterol diet. Signs of foam cell migration into the blood stream were not observed. The persistence of the xanthoma may be due to a lack of acceptors, such as high-density lipoproteins, that remove the cholesterol from the foam cells. During our 9-month observation period, some foam cells were degenerated and a few were fused with each other to transform into Touton-type giant cells. Nonfoamy histiocytes were infiltrated around these degenerating foam cells. The histiocytes may have transformed into foam cells by incorporating the lipids of the degenerated foam cells.

The clinical efficacy and safety of Roxithromycin (RU 28965, RU), a new macrolide preparation, were compared with those of Josamycin (JM) in superficial suppurative skin infections. The study was designed as double-blind controlled trial with daily dosages of 300 mg in RU group and 1200 mg in JM group. A total of 209 cases (RU:105; JM:104) was analyzed and the final global improvement rating was 82.9% in the RU group and 80.8% in the JM group; there was no significant difference between the two groups. Slight adverse reactions were observed in 3.6% (4 cases) of the RU group and in 4.6% (5 cases) of the JM group. In conclusion, RU at daily doses of 300 mg is as effective as JM at daily doses of 1200 mg in superficial suppurative skin infections.

A 7-month-old boy came to use with flat papules and small erosions on the extensor aspect of his left forearm and a linear arrangement of verrucous papules on the dorsum of his left hand. Histological examination revealed hyperkeratosis, parakeratosis, irregular acanthosis, and marked acantholysis from suprabasal through upper epidermis. This is the first reported case of linear epidermal nevus with acantholytic dyskeratosis in Japan.