Porphyria cutanea tarda.

Porphyria cutanea tarda (PCT) is a metabolic disorder of haem biosynthesis caused by decreased activity of uroporphyrinogen decarboxylase. Porphyria cutanea tarda is manifest by fragility, erosions, bullae, milia and scars on sun-exposed skin. Excess porphyrins in the skin interact with light of approximately 400 nm-wavelength radiant energy, forming reactive oxygen species. Porphyria cutanea tarda is categorized as familial, acquired or toxic. Factors that may induce clinical expression of PCT in susceptible individuals include alcohol, oestrogen, iron, polyhalogenated compounds and viral infections. Porphyria cutanea tarda is associated with an increased incidence of the haemochromatosis gene. Treatments for PCT include withdrawal of aggravating factors, phlebotomy and oral antimalarial medications.

Carney complex: in a patient with multiple blue naevi and lentigines, suspect cardiac myxoma.

Carney complex is characterized by spotty pigmentation (blue naevi and lentigines), myxomas (cardiac, cutaneous, mammary), endocrine over-activity (Cushing's syndrome, acromegaly), testicular tumours, and schwannomas. We report a male with multiple blue naevi, lentigines, testicular large cell calcifying Sertoli-cell tumour and four cardiac myxomas. The myxomas caused two cerebrovascular accidents and a myocardial infarction. All patients with multiple blue naevi or lentigines should be investigated for the life-threatening association of cardiac myxomas.

Vitamin A deficiency phrynoderma: due to malabsorption and inadequate diet.

We describe a patient with vitamin A deficiency phrynoderma caused by a combination of inadequate dietary intake of vitamin A and beta-carotene and malabsorption secondary to primary visceral myopathy and total colectomy.

Radiation-induced localized scleroderma in breast cancer patients.

Radiation-induced scleroderma in breast cancer patients appears to occur in approximately one out of every 500 patients. We report four cases that developed within 3 months of conservative breast surgery and postoperative radiation treatment. The reaction was contained entirely within the treatment field and demonstrated the typical features of this condition where the breast becomes erythematous, violaceous, indurated, retracted, and progressively pigmented. The breast tends to soften and become more comfortable over 1-4 years; however, significant induration, retraction and pigmentary changes remain. There appears to be no predictive factors. Radiation-induced scleroderma must be differentiated from cellulitis and recurrent breast cancer.