Porokeratotic eccrine ostial and dermal duct nevus.

Porokeratotic eccrine ostial and dermal duct nevus is a rare disorder characterized by distinctive histopathology. We describe a 6-year-old boy who had the typical palmar involvement and small discrete areas involving the midline of his back.

Chronic lymphoedema and angiosarcoma.

Angiosarcoma has frequently been described arising within chronic lymphoedema of the upper limb following mastectomy and radiotherapy for carcinoma of the breast. We report a case of angiosarcoma arising in a lymphoedematous leg that had been subjected to radiotherapy 20 years previously for Hodgkin's disease. The diagnosis was expedited once the patient noticed the development of bleeding nodules. Prognosis of angiosarcoma is poor with treatment options being wide-excision surgery, palliative radiotherapy or chemotherapy. Unusual bruised areas or bleeding nodules developing within chronic lymphoedematous limbs should be biopsied to exclude the diagnosis.

Hereditary palmoplantar keratoderma with deafness.

A pedigree showing the uncommon association of palmoplantar keratoderma with sensorineural deafness is described.

Partial lentiginosis.

A 14-year-old girl with partial unilateral lentiginosis affecting the left side of the neck, left shoulder and left upper arm is described. She also had a further patch of multiple lentigines over the right side of the face.

Cimetidine improves the therapeutic/toxic ratio of dapsone in patients on chronic dapsone therapy.

We have previously shown that cimetidine, given concurrently for 2 weeks to patients on chronic dapsone therapy, reduced methaemoglobinaemia by inhibiting the formation of the toxic hydroxylamine metabolite of dapsone. The aim of the present study was to examine the effect of this combination on the benefit/toxic ratio of dapsone over a longer period. Eight patients (six dermatitis herpetiformis, one linear IgA disease, one folliculitis decalvans) on long-term dapsone 50-100 mg daily, took cimetidine 1.6 g daily concurrently for 3 months. At 3-weekly intervals, a clinical assessment was made, plasma dapsone and methaemoglobin were measured, and parameters of oxidative haemolysis were monitored. The dapsone level rose from 2298 +/- 849 ng/ml (mean +/- SD) at baseline to 3006 +/- 1131 ng/ml at week 3 of cimetidine (P < 0.01). This rise in plasma dapsone was sustained during cimetidine administration, falling to 2446 +/- 954 ng/ml when cimetidine was stopped (P < 0.02). The methaemoglobin fell from 5.5 +/- 2.2% (mean +/- SD) at baseline to 3.9 +/- 1.1% at week 3 (P < 0.01), and remained low until week 12, when there was a return to baseline values (P < 0.01). The haemoglobin did not change from the baseline of 12.7 +/- 0.3 g/dl (mean +/- SD), and other parameters of haemolysis were unaltered. There was a fall in the visual analogue score for headache (P < 0.05), but this was not associated with any deterioration in control of the skin disorders. Hence, long-term concurrent cimetidine results in increased plasma dapsone levels without increased haemolysis, and is accompanied by reduced methaemoglobinaemia for more than 2 months.(ABSTRACT TRUNCATED AT 250 WORDS)

A family with pachyonychia congenita affecting the nails only.

A family with pachyonychia congenita in which affected individuals showed nail involvement only is described. Pachyonychia congenita is a rare hereditary disorder inherited in an autosomal dominant manner. Various classifications of pachyonychia congenita have been suggested but none indicates nail involvement as a solitary finding.

Kaposi's varicelliform eruption due to herpes simplex in Darier's disease.

A young woman with Darier's disease treated with acitretin developed Kaposi's varicelliform eruption, from which herpes simplex virus was isolated. Herpes simplex infection complicating Darier's disease is well recognized but uncommon. A young woman of 19 years is described who presented with fever and general malaise.

Unilateral localized idiopathic lipoatrophy.

An adult female is described in whom an area of lipoatrophy spontaneously appeared over the right side of the abdomen and chest. Idiopathic lipoatrophy affecting the trunk is rare and mainly described in Japanese children. We describe the condition occurring in an adult British female.

Scalp cyst with heterotopic brain tissue.

A multilocular scalp lesion was noticed at birth in a female infant. There was no underlying skull defect. Histological examination revealed neural tissue staining with S-100 and GFAP, but not with a neurofilament stain, which is in keeping with a glial cell origin. Heterotopic brain tissue is a rare developmental abnormality, which usually has no effect on neurological development. It should be considered in the differential diagnosis of scalp lesions in neonates.

Widespread syringomata in Down's syndrome.

A case of widespread syringomata occurring in a woman with Down's syndrome is described. Whereas periorbital syringomata are common in Down's syndrome, more widespread syringomata have only rarely been reported.

The use of cimetidine to reduce dapsone-dependent methaemoglobinaemia in dermatitis herpetiformis patients.

1. We have attempted to reduce dapsone-dependent methaemoglobinaemia formation in six dermatitis herpetiformis patients stabilised on dapsone by the co-administration of cimetidine. 2. In comparison with control, i.e. dapsone alone, methaemoglobinaemia due to dapsone fell by 27.3 +/- 6.7% and 26.6 +/- 5.6% the first and second weeks after commencement of cimetidine administration. The normally cyanotic appearance of the patient on the highest dose of dapsone (350 mg day-1), underwent marked improvement. 3. There was a significant increase in the trough plasma concentration of dapsone (2.8 +/- 0.8 x 10(-5)% dose ml-1) at day 21 in the presence of cimetidine compared with control (day 7, 1.9 +/- 0.6 x 10(-5)% dose ml-1, P less than 0.01). During the period of the study, dapsone-mediated control of the dermatitis herpetiformis in all six patients was unchanged. 4. Trough plasma concentrations of monoacetyl dapsone were significantly increased (P less than 0.05) at day 21 (1.9 +/- 1.0 x 10(-5)% dose ml-1) compared with day 7 (1.6 +/- 0.9 x 10(-5)% dose ml-1:control). 5. Over a 12 h period, 20.6 +/- 8.9% (day 0) of a dose of dapsone was detectable in urine as dapsone hydroxylamine. Significantly less dapsone hydroxylamine was recovered from urine at day 14 (15.0 +/- 8.4) in the presence of cimetidine, compared with day 0 (control: P less than 0.05). 6. The co-administration of cimetidine may be of value in increasing patient tolerance to dapsone, a widely used, effective, but comparatively toxic drug.

Inflammatory ringworm with unusual features.

Zoophilic dermatophyte infections are often inflammatory but severe widespread inflammatory lesions of glabrous skin, as in the female patient described, are unusual. Most cases of M. canis ringworm can be traced to an infected animal. This dermatophyte is associated with a variety of clinical presentations on glabrous skin and is being isolated with increasing frequency in some countries.