Juvenile xanthogranuloma of peripheral nerve: a report of two cases.

As a rule, juvenile xanthogranuloma (JXG) is a cutaneous lesion most often occurring in infancy. An inflammatory process of unknown etiology, it is self-limited and benign in nature. The spectrum of JXG has expanded to include adult examples, multifocal lesions, and ones arising at extracutaneous locations. Although a variety of extracutaneous sites may be affected, few reported lesions have involved cranial or peripheral nerves. Solitary examples have been reported in trigeminal nerve and spinal nerve root; affected individuals were children or adolescents. An optic nerve lesion has also been described. We describe two additional cases of JXG of nerve. One patient developed multiple dorsal nerve root lesions, as well as skin involvement. The other case featured isolated involvement of the left radial nerve. Both patients were adults with no known underlying systemic disorder. These cases further expand the spectrum of extracutaneous JXG, and underscore its consideration in the differential of nerve "tumors."

Xp microdeletion syndrome characterized by pathognomonic linear skin defects on the head and neck.

We describe a new case of a rare syndrome characterized by ocular abnormalities and pathognomonic linear skin defects. This syndrome is the result of an unbalanced translocation resulting in a deletion of the distal end of the short arm of the X chromosome. We report the thirteenth case and review the clinical and cytogenetic aspects of this disorder. In addition we discuss new findings pertaining to the histopathology of the skin lesions.

Widespread cutaneous bacillary angiomatosis and a large fungating mass in an HIV-positive man.

Bacillary angiomatosis (BA), an infection caused by a gram-negative rod, can be a multiorgan disease. The usual causative organism, Bartonella (formerly Rochalimaea) hensalae, has only recently been identified. Bartonella quintana has also been shown to cause some cases of cutaneous BA. We describe a patient with widespread cutaneous BA with probable bone involvement and a large fungating mass.

Hats: design and protection from ultraviolet radiation.

An estimated 400,000 non-melanoma skin cancers occur each year. A majority of them will develop on sun-exposed areas of the face, head, and neck. By virtue of having assignments that involve outdoor duty, often in areas of high ultraviolet radiation exposure, military personnel are at increased risk of developing these cancers. Hats provide a means of sun protection; however, some styles are more protective than others. Two styles of hats currently used by the military are compared.

Usefulness of retinoic acid in the treatment of melasma.

Melasma is a circumscribed brown macular hypermelanosis of the areas of the face and neck that are exposed to light. Clinical trials with various depigmenting formulations containing hydroquinone were conducted to determine the ideal concentration of hydroquinone, retinoic acid, and corticosteroids for the treatment of melasma. The compounds were tested with and without the concomitant use of topical sunscreen preparations. Based on the results of the trials and our earlier clinical experience, we conclude that treatment of melasma should involve the following: avoidance of sun exposure, constant use of broad-spectrum sunscreens, and topical application of a cream or lotion containing 2% hydroquinone and 0.05% to 0.1% retinoic acid (tretinoin). Patients should suspend use of oral contraceptives and other agents that promote skin pigmentation. The monobenzyl ether of hydroquinone should never be used in melasma therapy.