Zosteriform morphea in an immunocompetent patient.

Sir,

A 19-year-old female attended to our dermatological clinic with atrophic indurated hyperpigmented patches in a zosteriform distribution located on her left submammary [Figure 1] and back region [Figure 2]. There was no erythema in and around the lesions. The patient reported no personal or familiar medical history of interest except for an episode of herpes zoster in the same location two years before. Clinical examination did not reveal another cutaneous lesions. Blood cell count, general biochemistry, urinanalysis, thyroid profile, antinuclear antibodies, ESR (erytrocite sedimentation rate), CPR (C reactive protein), chest X-ray, and serologic test for Borrelia Burgdoferi showed no abnormalities. Serology for varicella-zoster virus showed negative IgM and positive IgG.

Figure 1

Hyperpigmented patch in zosteriform distribution on submmamary region in our patient

Figure 2

Morphea lesions on the back completing the zosteriform pattern

Histolopathologic examination showed thick bundles of collagen in reticular dermis orientated parallel to the skin surface. Cutaneous appendages were reduced. A perivascular inflammatory infiltrate composed of plasma cells and lymphocites was also observed. Our case was consistent with zosteriform morphea as an expression of isotopic Wolf response after the episode of herpes zoster. We began treatment with calcipotriol/betamethasone gel with mild therapeutic response.

The term “zosteriform” is commonly used to describe the morphological pattern of a skin dermatosis resembling the distribution of herpes zoster. Lichen planus, porokeratosis, common warts, fungal infections, naevus, skin metastases are some of the diseases that have been described following this pattern. In other terms, several types of cutaneous lesions have previously been described at the sites of herpes zoster scars.[1] This phenomenon that characterizes the occurrence of a new skin disease at the site of another has been termed as isotopic response by Wolf et al.[2] Although the cutaneous eruptions described in herpes zoster scars are variable, granuloma annulare and other types of granulomatous disorders are the most commonly reported reactions. Zosteriform morphea has been rarely described after herpes zoster in immunosuppressed[34] or immunocompetent[5] patients. It has been hypothesized that the viral infection changes the local immunity inducing a delayed-type hypersensitivity reaction to herpes zoster viral antigen or immune suppression. We coincide with Lopez et al,[6] that regarding the cytokine pattern of the inflammatory response a different dermatosis can be expressed, but in other way we cannot forget that other cases, as zosteriform lichen planus mainly, have been interpreted as a manifestation of Koebner's phenomenon. This pattern would be an expression of a viscerocutaneous reflex mechanism within the affected segments as a radicular irritation caused by abnormalities of the vertebral column. Nevertheless further studies are needed to perform a better interpretation of isotopic Wolf response.