Histopathologic findings in cutaneous cytomegalovirus infection.

When cytomegalovirus (CMV) involves the skin, viral inclusions are typically present within mesenchymal cells, e.g., endothelial cells, fibrocytes, and sometimes within inflammatory cells, e.g., macrophages, in contrast to infection in other organs in which inclusions are usually present within ductal epithelial cells. Two cases of cutaneous CMV are presented, one showing prominent findings within eccrine ductal epithelium and the other revealing mostly endothelial cells affected by CMV. Due to the range of cytologic changes induced by CMV observed in these cases, there seem to be early, fully developed, and late cellular changes brought about by CMV analogous to how herpesvirus (varicella, zoster, simplex) induces different changes depending on its stage of infection.

Herpes incognito.

Can a microscopist suspect that telltale histopathologic changes of infection by herpesvirus (varicella, zoster, or simplex) are nearby even when no diagnostic epithelial changes are present in the sections being studied? Punch-biopsy specimens from three patients are presented; in two of those cases herpesvirus infection was not even a clinical consideration. The initial histopathologic sections from these patients did not show changes of herpesvirus infection, but step sections revealed focal diagnostic changes. Atypical lymphocytes were present in each of these cases. When atypical lymphocytes are found in concert with a pattern of an inflammatory-cell infiltrate that does not conform precisely to any well-defined entity, a microscopist should consider that the findings may represent changes near infection by herpesvirus. In addition, we reviewed every case we diagnosed as herpesvirus infection over an 18-month period and found that in just over two thirds of those specimens (32 out of 45 cases), atypical lymphocytes accompanied the characteristic epithelial changes induced by herpesvirus.

Epithelial sheath neuroma: a new entity.

The authors describe four examples of a peculiar cutaneous lesion characterized histopathologically by a proliferation of enlarged nerve fibers ensheathed by squamous epithelium involving the superficial dermis. The perineural epithelial sheaths were composed of uniform squamous epithelium with evidence of cornification in the form of dyskeratotic cells or resulting in orthokeratotic basket-weave corneocytes. Immunohistochemical studies confirmed the epithelial and neural nature of the two components of the lesions, with the nerve fibers expressing immunoreactivity for S-100 protein, neurofilaments, CD57, and nerve growth factor receptor, whereas the perineural epithelial sheaths showed immunoreactivity for cytokeratins. The authors propose the term "epithelial sheath neuroma" for this lesion and believe that it is a distinct and a previously undescribed benign neoplasm of both cutaneous nerves and epithelial elements.

Mycosis fungoides palmaris et plantaris.

BACKGROUND: Mycosis fungoides primarily localized to the palms and soles is rare and has been previously reported as cutaneous lymphoma in four patients or as Woringer-Kolopp disease in eight patients. OBSERVATIONS: Four patients were initially diagnosed and treated unsuccessfully for various palmoplantar dermatitides until histopathologic findings revealed mycosis fungoides. Each case exhibited a clonal rearrangement of T-cell receptor gamma genes and immunohistochemical studies consonant with mycosis fungoides. All patients had limited skin involvement without evidence of extracutaneous involvement. CONCLUSIONS: Mycosis fungoides palmaris et plantaris is an uncommon expression of mycosis fungoides that manifests primarily on the palms and soles and clinically may mimic various inflammatory palmoplantar dermatoses. A biopsy is recommended in the evaluation of recalcitrant palmoplantar dermatoses.

Enhanced elastin and fibrillin gene expression in chronically photodamaged skin.

Cutaneous aging consists of chronologic aging as well as actinic damage, referred to as photoaging. Most of the morphologic changes associated with an aged appearance result from actinic damage to the skin. The morphologic changes in sun-damaged skin are associated with accumulation of material having the staining characteristics of elastin, known as solar elastosis, in the superficial dermis. Previous studies have demonstrated the presence of elastin within areas of solar elastosis; however, little is known about the mechanisms leading to elastin accumulation in photoaged skin. In addition, fibrillin, the fibrillar component of elastic fibers, has been found in small amounts in solar elastosis. In this study we demonstrate increased elastin mRNA levels in photoaged skin, as well as increased elastin and fibrillin mRNAs in skin explant-derived fibroblasts using Northern hybridizations, compared with controls from sun-protected sites of the same individual. Increased elastin mRNA levels result from transcriptional upregulation of the gene, as demonstrated by transient transfections with a human elastin promoter/chloramphenicol acetyltransferase construct. Elevated mRNA levels were also correlated with increased elastin and fibrillin deposition in paired biopsy specimens from photodamaged and non-sun-exposed skin, as demonstrated by immunohistochemical staining. Thus, approaches to counteract transcriptional activation of elastin gene expression may be useful in preventing the changes associated with cutaneous photoaging.

Solitary congenital self-healing reticulohistiocytosis.

Congenital self-healing reticulohistiocytosis (CSHR) was first described in 1973 by Hashimoto and Pritzker. Since then, both multiple and solitary forms have been described. We report a further case of solitary congenital self-healing reticulohistiocytosis. CSHR is a rare disorder which frequently presents a diagnostic dilemma in the newborn. Nodular forms of systemic Langerhans cell histiocytosis may present in a manner similar to CSHR. Because their differentiation on histopathological grounds is impossible, physical examination, laboratory investigations, and follow-up are necessary to ensure a lack of systemic involvement. Although previously thought to represent a rare variant of CSHR, solitary lesions of CSHR account for almost 25% of reported cases. A review of the literature relating to solitary CSHR, and a consideration of the differential diagnosis of a solitary congenital nodule, are also presented.

Leukemia cutis in congenital leukemia. Analysis and review of the world literature with report of an additional case.

BACKGROUND: Congenital leukemia cutis is rarely reported in the dermatology literature despite various authors citing 50% of infants with congenital leukemia have skin involvement. These seemingly disparate facts prompted a review of the world literature that was performed by searching the MEDLINE database from 1966 up to and through December 1992, reviewing Index Medicus for the years prior to computerized MEDLINE search, and reviewing appropriate case report references. OBSERVATIONS: A 2-month premature male infant was born with 182 x 10(9)/L circulating monoblasts, prominent hepatosplenomegaly, and multiple firm blue and red cutaneous nodules. CONCLUSION: Approximately 175 cases of congenital leukemia have been reported with at least 41 and possibly 56 cases identified with leukemia cutis. Specific cutaneous leukemic infiltrates occur in 25% to 30% of infants with congenital leukemia and usually appear as firm blue, red, or purple nodules in a generalized distribution. In contrast to the 50% incidence of gingival and oral infiltrates reported in adult monocytic leukemia, only 1% of congenital leukemia patients have oral involvement. Congenital leukemia cutis may precede other manifestations of leukemia by as much as 4 months. Whereas leukemia cutis is associated with a poor prognosis in adult leukemics, the natural history of congenital leukemia is not altered by leukemia cutis.

Home UV phototherapy of early mycosis fungoides: long-term follow-up observations in thirty-one patients.

BACKGROUND: In 1982 we reported our preliminary observations on the use of home UV phototherapy for patch and early plaque phase mycosis fungoides (MF). OBJECTIVE: Our purpose was to present follow-up data of the original 31 patients, covering an interval of up to 15 years. METHODS: All patients used a commercially available UV phototherapy unit that contained four Westinghouse FS40 fluorescent lamps for daily exposures of their non-sun-exposed skin regions. RESULTS: A complete clinical and histologic response to home phototherapy occurred in 23 patients (74%) with a maximum duration of the response from 5 months to more than 15 years (median 51 months). After maintenance phototherapy was discontinued, seven patients (23%) had a sustained disease-free interval lasting more than 58 months (median > 90 months). This indicates that cure may have been achieved in a minority of patients. Phototherapy was well tolerated without evidence of significant photodamage or photocarcinogenicity. CONCLUSION: These observations indicate that home phototherapy may be a therapeutic option for treatment of selected patients with early MF.

Cutaneous epithelioid hemangioendothelioma without systemic involvement.

Epithelioid hemangioendothelioma (EH) is a unique vascular tumor characterized histologically by epithelioid endothelial cells. A case of EH arising from the dermis and presenting as a nodule of the palm is described. To our knowledge, this is the third report of a cutaneous presentation of EH and the first report of a patient with this rare neoplasm with solitary cutaneous involvement. A review of the literature is also presented.

Dilated pore nevus. A histologic variant of nevus comedonicus.

Histology of a nevus comedonicus showed aggregates of dilated follicular cysts reminiscent of dilated pore of Winer. This finding has not been previously reported. We propose the term dilated pore nevus for this lesion, which we conceive to be a histologic variant of nevus comedonicus, similar to porokeratotic eccrine ostial and dermal duct nevus.