Portal de Periódicos da CAPES

ACTINIC VARICELLA

1996; Lippincott Williams & Wilkins; Volume: 15; Issue: 10 Linguagem: Inglês

10.1097/00006454-199610000-00023

1532-0987

Derry Ridgway, Sean P. Avera, Arthur Jaffe,

Vector-Borne Animal Diseases

The rash of chickenpox commonly begins on the chest, back, abdomen and scalp. New lesions appear in crops with progressive involvement of the face and proximal and then distal extremities. The rash is called centripetal, reflecting the early appearance and greater concentration of vesicles on the trunk. Case report. A healthy, untanned 3½-year-old girl from the Pacific Northwest wore a V-strapped swimsuit while playing at her grandmother's pool in Southern California on June 30 and July 1. Although sunscreen was applied to exposed areas, a mild sunburn developed on July 1. Pruritic vesicular lesions appeared for several days beginning on July 3. The photograph (Fig. 1) was taken on July 4. The patient's 5-year-old brother had had varicella 2 weeks before the onset of her rash. Discussion. On the neck and trunk, areas of skin with recent or chronic sun exposure may show a greater density of vesicles. When a recent sunburn has left demarcated clothing lines, the concentration of rash changes abruptly at the line of erythema, as shown in Figure 1. The first report of photolocalized (actinic) varicella was published in 1973.1 Thirteen subsequent cases, including the child described in this report have been reported.2-10 The patients have ranged in age from 2 to 23 years; three cases occurred in adults. Twelve patients were female. Nine cases, including the present one, involved recent sun exposure with mild sunburn.1, 5-7, 9, 10 In five cases the skin areas with greater concentrations of vesicles were tanned after chronic sun exposure.2-4, 7, 8 In three patients all vesicles on sun-damaged skin appeared at once.5, 6 Other cases showed the usual cropping of lesions.1, 4, 7, 10 When patients with actinic varicella are seen early in the course of the rash and without a known exposure to chickenpox, the unusual distribution can obscure the diagnosis.2, 3, 6, 8, 9 The exanthem of varicella appears after the onset of the second viremic phase of illness11; proposed explanations for the more extensive involvement of sun-exposed skin involve changes in viral access or replication in the epidermis during that period. Erythematous skin may have a proportionally greater exposure to viral particles because of increased blood flow1-3 or as a consequence of increased capillary permeability and easier escape of free virus7-9 or infected lumphocytes.2, 3, 7 Alternatively viral replication may be enhanced in the inflamed epidermis,3, 9 as a result of changed incubation temperature,2, 7, 8 as an indirect effect of cell membrane damage8, 9 or as blunting of local anti-viral immunologic activity.8-10 Observations based on the propagation of varicella in neoplastic melanocytes12, 13 suggest that melanocytes are involved in the replication and distribution of virus in the dermis. Infected local melanocytes, activated by recent ultraviolet radiation, might promote a denser distribution of infective particles.2-4, 7, 9 Some observers believe that preferential involvement of sun-exposed skin by the rash of chickenpox may be uncommon.3, 4, 6, 7, 9, 10 Findlay et al.6 postulated that increased sun-seeking behaviors during the last half-century may have unveiled a previously unrecognized characteristic of the varicella virus. These authors report on the experience of Dr. Marion Sulzberger who was taught about actinic chickenpox in the 1920s. According to Dr. Sulzberger, during hospital epidemics of chickenpox children with cots nearer the windows had more extensive rashes, and individual children had more pox on their sun-exposed sides.6 Because the observation of actinic chickenpox appears to be confined to the neck and trunk where the densest exanthem is expected, the phenomenon may not be rare at all. It might even be universal, requiring for expression the coincidence of a demarcated sun line at the time of exanthem. The apparent preference for females among reported cases may be an artifact of the more arresting contours of the sunburns and suntans produced by girl's swim wear, exemplified by the “V” on the back of our patient. Proposals for the mechanism of actinic varicella must account for an anticentripetal influence (sun exposure) applied to a fundamentally centripetal rash. Explanations that rely on activation of melanocytes are attractive given that they explain cases with acute sunburn as well as long established suntan. Proposed explanations based on skin trauma fail to include the suntan cases, unless one supposes the tan has concealed a more recent exposure and burn (a sequence specifically denied by one observer4). For a sunburned child seen in the early hours of varicella rash, acyclovir might be used to reduce the severity of rash and the potential for scarring. Except for the unusual distribution of vesicles, the untreated child reported here had a typical course of chickenpox. Her rash was more severe than her brother's, as is common for secondary cases acquired by a household contact. Among other reported cases the only clinically remarkable aspect of chickenpox complicated by actinic distribution of the truncal rash was the considerable effort expended in establishing a diagnosis in cases without a known exposure history. Physician awareness of the phenomenon of actinic varicella will safeguard such patients against unnecessary diagnostic evaluations. Derry Ridgway, M.D.; Sean P. Avera, D.D.S.; Arthur Jaffe, M.D. University of California Berkeley, CA (DR) Department of Periodontology School of Dentistry (SPA) Department of Pediatrics School of Medicine (AJ) Doernbecher Children's Hospital (AJ) Oregon Health Sciences University Portland, ORFIG. 1: Mild sunburn and lesions of chickenpox in various stages on the back of a 3-year-old girl. There is relative sparing of the nonerythematous skin which was protected from sun exposure by the trunks and straps of her swimsuit.