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new opportunistic infection, was first described when small, apparently gram-negative bacilli were noted on electron microscopic examination of a cutaneous lesion suspected of being Kaposi's sarcoma. Cutaneous bacillary angiomatosis, sometimes called epithelioid angiomatosis, is marked by red papules and nodules and, less often, rounded subcutaneous masses. On a biopsy specimen, there is a proliferation of capillaries with greatly protuberant endothelial cells. The lesions may easily be mistaken for pyogenic granulomas, Kaposi's sarcoma, or angiosarcoma. Features that enable a specific diagnosis of bacillary angiomatosis to be made include numerous neutrophils, nuclear dust, and purplish granular material that proves, on electron microscopy or Warthin-Starry stain, to consist of bacteria. Most patients respond well to a regimen of erythromycin, 2 grams per day. Recent attention has focused on the identity of the causative bacillus and on the spectrum of internal disease produced by the organism. Because the agent of bacillary angiomatosis causes vascular proliferation, there has been speculation that it is related to Bartonella bacilliformis, which causes an acute febrile illness known as Oroya fever and a chronic illness with numerous cutaneous vascular lesions known as verruga peruana. Recent studies using whole cell fatty acid chromatography have shown that the agent of bacillary angiomatosis has a similar profile to Bartonella species. Because some of the original patients had been scratched by cats and because the bacillus shows the same restricted staining pattern as does the bacillus of cat-scratch disease, the proposal has been made that bacillary angiomatosis is caused by the cat-scratch disease bacillus. This remains unproved. So far, culturing the bacillus using conditions favoring growth of the cat-scratch disease bacillus has proved difficult. A third possibility has been established by molecular biologic studies. Sequencing of the 16S RNA gene has shown that the agent of bacillary angiomatosis is most similar to a rickettsia, Rochalimaea quintana, the agent of trench fever, which is clinically unlike bacillary angiomatosis. The spectrum of internal disease caused by this organism, with or without cutaneous lesions, has expanded. Soft tissue masses, lymphadenopathy, and dramatic hepatomegaly and splenomegaly have been seen in affected patients. Peliosis hepatis (the formation of blood-filled cysts in the liver) is an unusual consequence of infection. Clusters of bacilli inhabit the connective tissue that rims these cysts. The internal manifestations of bacillary angiomatosis also respond to antibiotic therapy. Fatal untreated cases have occurred. The next few years will doubtless see more precise identification of the organism, as well as the documentation of additional cases in non-HIV-infected patients. PHILIP E. LE BOIT, MD San Francisco, California

REFERENCES LeBoit PE, Berger TG, Egbert BM, Beckstead JH, Yen TS, Stoler MH: Bacillary angiomatosis: The histopathology and differential diagnosis of a pseudoneoplastic infection in patients with human immunodeficiency virus disease. Am J Surg Pathol 1989; 13:909-920 LeBoit PE, Berger TG, Egbert BM, et al: Epithelioid haemangioma-like vascular proliferation in AIDS: Manifestations of cat scratch disease bacillus infection? Lancet 1988; 1:960-963 Perkocha LA, Geaghan SM, Yen TSB, et al: Clinical and pathological features of bacillary peliosis hepatis in association with human immunodeficiency virus infection. N Engl J Med 1990; 323:1581-1586 Relman DA, Loutit JS, Schmidt TM, Falkow S, Tompkins LS: The agent of bacillary angiomatosis: An approach to the identification of uncultured pathogens. N Engl J Med 1990; 323:1573-1580

Suntan Parlors-A New Hazard to Health WITH THE DEVELOPMENT during the past 20 years of highintensity lamps emitting UVA, the suntan facility industry has burgeoned. In California, it is estimated that there are about 2,000 such facilities. UVA is long-wave ultraviolet light in the range of 320 to 400 nm. Unlike UVB (280 to 320 nm), it passes through window glass. It is present throughout the day and during the entire year. UVA penetrates the epidermis into the dermis. Because of this, it can damage not only the Langerhans cells in the basal layer ofthe epidermis but also collagen tissue, the lens and retina of the eye, and even blood vessels. A growing body of literature indicates the potential for the development of basal and squamous cell carcinomas, as well as the development of cutaneous melanomas on the basis of exposure to UVA. Beginning in the 1980s, it was noted that an increasing number of eye injuries were caused by exposure to UVA in suntan facilities. Severe burning of the skin, exacerbation of autoimmune illnesses such as lupus erythematosus, photoallergic reactions of the skin, premature aging of the skin, an increase in the number of skin cancers, and one death have been reported. The use of suntan parlors apparently contributed to an epidemic of phytophotodermatitis among grocery workers handling fresh produce and fresh flowers. It is hoped that an awareness of the hazards of UVA will lead to decreased exposure to this harmful agent. MICHAEL J. FRANZBLAU, MD

Greenbrae, California REFERENCES Council on Scientific Affairs: Harmful effects of ultraviolet radiation. JAMA 1989; 262:380-384 Health Hazard Evaluation Determination, Report #HE 80-225. Cincinnati, Ohio, National Institute for Occupational Safety and Health, June 1982 Jones SK, Moseley H, Mackie RM: UVA-induced melanocytic lesions. Br J Dermatol 1987; 117:111-115 Morbidity-Mortality Report: Injuries associated with ultraviolet tanning-Wisconsin. JAMA 1989; 261:3519-3520 Retsas S: Sun beds and melanoma. Br Med J 1989; 286:892 Walter SD, Marrett LD, From L, Hertzman C, Shannon HS, Roy P: The association of cutaneous malignant melanoma with the use of sun beds and sunlamps. Am J Epidemiol 1990; 131:232-243

Carbon Dioxide Laser Treatment of Actinic Cheilitis ACrINIC CHEILITIS is a diffuse premalignant change of the lip caused by long-term sun exposure and possibly aggravated by the use of tobacco products. Clinically it consists of a whitened, thin epithelium with or without fissures and slow-toheal erosions. It may look and feel like "chapping," but it is found almost exclusively on the lower lip, which receives more ultraviolet exposure than the upper lip because it protrudes forward and is oriented upward. This parallels the 10:1 increased incidence of an invasive malignant lesion on the lower lip compared with the upper lip. The carbon dioxide laser is well suited to precisely remove this premalignant epithelium with less morbidity and lower recurrence rates than other available techniques, such as liquid nitrogen, topical fluorouracil, tretinoin (Retin-A), and vermilionectomy with mucosal advancement flap repair. The vermilion border is marked and the entire vermilion infiltrated with local anesthetic to smooth its surface, which may be preceded by a submental block or topical mucosal anesthetic to ease the pain of injection. The carbon dioxide

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laser is used in a defocused mode, usually from 2 to 4 W and at a size of between 2 and 4 mm in diameter. One or more passes with the laser are made until the entire lower lip has a mottled white-pink appearance. This procedure is done as much by feel and experience as anything else. Small areas that retain a rough surface can be precisely vaporized to attain a uniform appearance. There is no blood loss and minimal early postoperative pain because nerves and blood vessels are sealed by the laser. Postoperative care consists of peroxide compresses and antibiotic ointment applied several times a day until the wound is fully epithelialized in 7 to 14 days. Before laser therapy is undertaken, a biopsy should be taken from any ulcerated or indurated (firm) areas to exclude invasive squamous cell carcinoma. Clinical or pathologic examination may also be required to exclude lichen planus, contact dermatitis, and discoid lupus erythematosus before such treatment. Carbon dioxide laser treatment of actinic cheilitis is an efficient, office-based procedure that results in minimal scarring and a lower recurrence rate than other destructive therapies. It offers cost savings and fewer complications than vermilionectomy and mucosal advancement. The removal of premalignant changes of the lip can be expected to reduce the occurrence of potentially metastasizing labial squamous cell carcinomas. ROBERT S. SCHEINBERG, MD

Oceanside, California REFERENCES Stanley RJ, Roenigk RJ: Actinic cheilitis: Treatment with the carbon dioxide laser. Mayo Clin Proc 1988; 63:230-235 Whitaker DC: Microscopically proven cure of actinic cheilitis by CO2 laser. Lasers Surg Med 1987; 7:520-523

Treatment of Scabies and Similar Infestations SCABIES CONTINUES TO BE a source of substantial discomfort in our society. The typical infestation is acquired by direct contact with the Sarcoptes scabiei. The female mite burrows and lays her eggs in thin keratinized epithelium. Intense nocturnal pruritus develops in most patients about three weeks after contracting the initial infestation, due to an allergic or irritant response to the mite's secretions. Classic areas of distribution for the linear burrows include the web spaces of the fingers, toes, axillae, groin, and waist. A vigorous immunologic reaction to the mite may cause widespread skin eruption, with few typical burrows. In addition, young children and elderly patients may have involvement of the palms, soles, scalp, and face. Immunocompromised patients, especially those infected with the human immunodeficiency virus, are more susceptible and may even have Norwegian scabies marked by hyperkeratotic lesions and numerous mites. Skin scraping is the only consistent means of detecting these mites and evaluating treatment. Any unexplained pruritic skin lesions should be scraped and examined by potassium hydroxide wet mount or with mineral oil under a microscope to look for the mite, fecal debris, and eggs contained in the burrow. In rare cases, a biopsy is required to establish an accurate diagnosis, especially for Norwegian scabies. The following important principles are used in treating patients with scabies:

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* Prescribe a limited amount of a suitable medication; * Avoid overtreatment; * Treat the whole body from neck to toes. In infants and debilitated, bedridden patients, the head and face also require treatment; * All household contacts (and frequent visitors) need to be treated simultaneously; * Give detailed verbal and written instructions; * Patient should launder underclothing and bedding after completion of treatment and not use again for three days; * Do a follow-up inspection at one and four weeks; * Always recheck and rescrape patients if any lesions persist; and * Caution patients that no matter what treatment is provided, the itching will commonly persist for several weeks after adequate treatment. Lindane (1% Sy-benzene hexachloride [Kwell]) has been until recently the standard scabicide in the US because of its efficacy and cosmetic acceptability. Lindane displays some toxicity, which may include serious neurotoxicity. Although most reported cases have involved overexposure or mishandling, risks of such events must be considered when the drug is provided. There have also been reports of resistance to lindane in California, which has prompted the California Department of Health to recommend alternative therapies. Permethrin 5% cream has recently been introduced as a highly effective and novel scabicide, that may largely replace lindane for the treatment of scabies. Permethrin is a photostable synthetic pyrethroid with potent insecticidal activity and low mammalian toxicity. The 5% permethrin cream has been used successfully in heavily infested communities in which scabies had been endemic. Permethrin cream has a lower potential for neurotoxicity and may be preferable for the treatment of scabies, particularly in young children. Because controlled studies are lacking in children younger than 2 months and pregnant women, permethrin is still not recommended for these patients. The major disadvantage of this drug is its cost, being 10 to 12 times as expensive as lindane. Other scabicides include crotamiton (Eurax), which is not very effective but has an antipruritic effect. Sulfur (3% to 6% in petrolatum or cetaphil lotion) is used primarily in pregnant women and young infants in whom lindane and permethrin are not safe. Human contact with other species of scabies mite, such as Sarcoptes scabiei variant canis, the cause of canine sarcoptic mange, may cause pruritic papules where the mite bites, but the mite will not be able to burrow and set up an infestation similar to human scabies. Thus, treatment of the pet is essential, and a scabicide for the human friend is not indicated. Topical antipruritics and antihistamines will help control itching. DIANNE R. LEVISOHN, MD

Albuquerque, New Mexico REFERENCES Schultz MW, Gomez M, Hansen RC, et al: Comparative study of 5% permethrin cream and 1% lindane lotion for the treatment of scabies. Arch Dermatol 1990; 126:167-170 Taplin D, Meinking TL: Scabies, lice, and fungal infections. Primary Care 1989; 16:551-576 Taplin D, Meinking TL, Chen JA, Sanchez R: Comparison of crotamiton 10%o cream (Eurax) and permethrin 5% cream (Elimite) for the treatment of scabies in children. Pediatr Dermatol 1990; 7:67-73 Yonkosky D, Ladia L, Gackenheimer L, Schultz MW: Scabies in nursing homes: An eradication program with permethrin 5% cream. J Am Acad Dermatol 1990; 23:1133-1136

Carbon dioxide laser treatment of actinic cheilitis.

192 EPITOMES-DERMATOLOGY EPITOMES-DERMATOLOGY 192 new opportunistic infection, was first described when small, apparently gram-negative bacilli we...
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