Hereditary hemorrhagic telangiectasia.

A 45-year-old man with hereditary hemorrhagic telangiectasia (HHT) presented with numerous mucocutaneous telangiectases, recurrent nosebleeds, and several first degree relatives with similar symptoms. HHT has been linked to mutations in the genes endoglin and activin receptor-like kinase-1 (ALK-1), which are located on chromosome 9q33-34 and 12q13, respectively. The resultant proteins mediate binding and signaling of transforming growth factor-beta.

Eosinophilic cellulitis and dermographism.

A 26-year-old man presented with a history of intermittent erythematous plaques on his hands and legs. A peripheral blood eosinophilia was noted. Histopathologic examination showed numerous eosinophils and characteristic flame figures.

Telangiectasia macularis eruptiva perstans.

A 45-year-old man presented with lesions clinically and histologically consistent with telangiectasis macularis eruptiva perstans (TMEP). TMEP is a rare form of mastocytosis, which is localized to the skin, although systemic involvement has been reported. A mutation in the c-kit proto-oncogene is thought to be involved in mast cell hyperplasia in some patients with mastocytosis.

Subcutaneous T-cell lymphoma.

A 70-year-old woman presents with a 2-year history of intermittent, subcutaneous nodules. The patient was otherwise asymptomatic. A biopsy specimen was consistent with a subcutaneous T-cell lymphoma, a rare subset of peripheral T-cell lymphoma; when accompanied by the hemocphagocytic syndrome, it can be rapidly fatal.

Cutis verticis gyrata.

An 82-year-old man had deep, linear skin folds on the scalp. The patient did not have a history of neuropsychiatric disorders and was generally in good health except for diabetes mellitus, hypertension, and benign positional vertigo. Cutis verticis gyrata is a term used to describe the appearance of deep, linear skin folds in the scalp.

Idiopathic CD4+T-cell lymphocytopenia associated with vitiligo.

The syndrome of idiopathic CD4+ T lymphocytopenia (ICTL) is defined as the persistent depletion of peripheral blood CD4+ T lymphocytes below 300 cells/mm(3) or less than 20% of the total lymphocytes in the absence of either HIV infection or other known causes of immunodeficiency. To date no known viral origin has been identified. ICTL has a variable clinical course ranging from patients with minimal symptoms to those who have died from opportunistic infections.