Histopathologic features seen in cutaneous photoeruptions in HIV-positive patients

Background There have been scattered reports of HIV+ patients with increased reactions to light as well as anecdotal reports of HIV+ patients with increased morbidity secondary to radiation therapy. Methods As a part of a military study of HIV+ patients, we followed 987 patients for cutaneous disease for 4 years. All patients were questioned on a periodic basis about increased sensitivity to light. These patients received a physical examination at each protocol visit, and they were given the opportunity to receive all their dermatologic care within the HIV clinic. Fourteen of the patients with photo-induced eruptions were evaluated clinically at the time of the eruption, and 11 of these were biopsied. Results Thirty-three of the patients reported photo-induced reactions unrelated to oral medications. Although sensitivity to light often began in the early stages of HIV disease, reactions became more severe and more chronic with disease progression. Histologic features varied from few to numerous apoptotic/necrotic keratinocytes within the mid to upper levels of the epidermis associated with a perivascular inflammatory infiltrate, to apoptotic/necrotic keratinocytes throughout an acanthotic epidermis with a liehenoid/interface infiltrate. Conclusions Although the pathogenesis of these light reactions is not known, these reactions may be related to depletion of endogenous scavengers which results in increased oxidative stress and is modulated by the pattern of immune dysregulation and metabolic dysregulation induced by HIV disease.     

Histopathologic features seen in Gianotti-Crosti syndrome secondary to Epstein-Barr virus

BACKGROUND: Gianotti-Crosti syndrome (GCS) or infantile papular acrodermatitis presents as a symmetric erythematous lichenoid papular and papulovesicular eruption of the face, extremities, and buttocks, usually occurring in young children. GCS has been associated with hepatitis B and enteroviruses, as well as Epstein-Barr virus (EBV) and, rarely, cytomegalovirus. OBJECTIVE: The purpose of this study was to use immunohistochemical studies to determine the pattern of the lymphoid infiltrate and evidence for viral antigens in cases of EBV-associated GCS. METHODS: Routine histologic and immunohistochemical stains were evaluated in 3 patients with typical GCS. All 3 patients showed serologic evidence of an acute EBV infection. The immunohistochemical studies included monoclonal antibodies for CD3, CD4, CD8, CD20, TIA, S-100 protein, KP-1, EBV latent membrane antigen-1, and EBV-encoded nuclear antigen-2. RESULTS: All biopsy specimens showed minimal epidermal spongiosis with marked papillary dermal edema. The associated inflammatory infiltrate showed a mixed mononuclear cell infiltrate with rare eosinophils. Immunohistochemical stains for latent membrane antigen-1 and EBV-encoded nuclear antigen-2 were negative for EBV. The majority of mononuclear cells showed membrane staining for CD3, 30% to 40% of the CD3 mononuclear cells showed positive staining for CD4, and 50% to 60% showed positive staining with CD8. TIA(+) cells appeared to correspond to the CD8(+) cells. CONCLUSION: Although papillary dermal edema has been reported within the spectrum of histologic findings in GCS, it was marked and a consistent finding in the 3 cases in which EBV was the most likely etiologic agent. The presence of large numbers of cytotoxic T cells in the inflammatory infiltrate may have accentuated this histologic finding and may be a relatively distinctive histologic finding with GCS associated with EBV.     

Histopathologic features of exanthematous drug eruptions of the macular and papular type

Although exanthematous drug eruptions of the macular and papular type are common and often cause diagnostic problems, histopathologic features are not precisely defined in the literature. We present the first prospective histopathologic study of maculopapular drug eruption in 48 patients in whom the diagnosis had been made on the basis of clinical examination, history of a known offending drug, and follow-up. Because more than 1 biopsy was taken in 11 patients, 60 biopsy specimens could be examined. The most consistent epidermal features were mild spongiosis mainly of the lower layers (97% of biopsies), some hyperplasia (72%), a few lymphocytes (82%), and neutrophils (32%). The dermoepidermal junction revealed discrete vacuolization (97%), scattered lymphocytes (75%), and rare necrotic keratinocytes (32%). All cases showed a dermal perivascular inflammatory infiltrate that was superficial only in 72% of biopsies and superficial and deep in 28% of biopsies. An interstitial infiltrate in the papillary dermis could be found in 93%, more often patchy than lichenoid. In general, the perivascular infiltrate was mild and composed of lymphocytes (100%), eosinophils (60%), and neutrophils (50%). In the papillary dermis, neutrophils often outnumbered the eosinophils. Another feature were the clusters of neutrophils (38%) and eosinophils (20%) in the lumina of dilated, otherwise normal, blood vessels. Rashes induced by anticonvulsants and anxiolytics were characterized by predominance of neutrophils and largish lymphocytes. Edema of the papillary dermis was encountered frequently (85%), whereas wiry collagen bundles were an exceptional finding. In conclusion, our study defined a constellation of histopathologic findings highly suggestive of the diagnosis of exanthematous drug eruption of the macular and papular type.     

Histopathologic features seen in sulfur mustard induced cutaneous lesions in hairless guinea pigs

Sulfur mustard (SM), a chemical warfare agent first used early in the 20th century, has re-emerged in the past decade as a major threat around the world. At present, there are no effective therapeutic measures for SM exposure. Because the skin as well as other interface epithelial surfaces are the first tissues effected as this agent is absorbed, reactions within the skin are an area of active research into the mechanism of action of this alkylating agent. The euthymic hairless guinea pig has been used as the animal model for the study of SM induced injuries because of morphologic similarity of its skin to human skin, with a multiple layer epidermis, and because this animal has a normal immune system. We reviewed 102 biopsy specimens from 51 animals exposed to three different dose times of saturated SM vapor. Histopathologic evidence exists for increased programmed cell death as well as cellular necrosis, subepidermal blister formation, and delayed re-epithelialization secondary to problems with adhesion. Information obtained from this study adds to the body of information important in the investigation of the mechanisms of action of SM.     

Histopathologic features in vitiligo

Nevus depigmentosus is a congenital disorder characterized by a nonprogressive hypopigmented lesion, which may not be apparent at birth. Thus, it is sometimes difficult to differentiate vitiligo from nevus depigmentosus only by clinical features. We postulated that the histologic changes in lesional and perilesional skin might be different in the 2 conditions. We took biopsies from both lesional and perilesional skin of 100 cases of vitiligo to assess the number of melanocytes, the amount of melanin, dermal inflammatory infiltrate, and other changes. We compared them with 30 cases of nevus depigmentosus. Histologically, lesions of vitiligo showed more basal hypopigmentation and dermal inflammation than perilesional normal skin. With Fontana-Masson staining, 16% of cases of vitiligo showed the presence of melanin. The ratio of pigmented area to epidermal area was 0.06% in vitiligo, whereas 17% in perilesional normal skin and 8.9% in nevus depigmentosus. In NKI/beteb staining, 12% of vitiligo showed the presence of melanocytes, and their average number was 7.68 per square millimeter. The number of melanocytes was also decreased in nevus depigmentosus but not as much as in vitiligo. We also confirmed the presence of melanocytes in 1 of 3 cases of vitiligo by electron microscopy. In conclusion, there are a few melanocytes and melanin in some cases of vitiligo. Therefore, the diagnosis of vitiligo should be made considering these points.     

Histopathologic features of HIV-associated skin disease

The cutaneous lesions that occur in individuals infected with the human immunodeficiency virus are often more severe than those in normal individuals. Of great importance is the fact that many common disorders may show atypical clinical and histologic features, which can lead to misdiagnosis and delayed or inadequate therapy. Therefore, knowledge of pitfalls combined with adequate biopsy and thorough histologic evaluation give the greatest chances of successful diagnosis and treatment.     

Histopathologic features of superficial granulomatous pyoderma

Study of the histopathologic pattern of 28 cases of superficial granulomatous pyoderma demonstrated an ulcerative, verrucous pyoderma of the superficial dermis. Focal abscesses in the subepidermis or dermis were juxtaposed with granuloma formation and plasma cell inflammation. Hemorrhage and granulation tissue were present. The clinical lesions are indolent, and this feature is confirmed by chronic inflammatory elements, including sinus tract formation and focal fibrosis. Superficial granulomatous pyoderma must be added to the histologic differential diagnosis of the vegetative and ulcerative granulomas: blastomycosis, tuberculosis verrucosa cutis, and bromoderma.     

Histologic features of melanocytic nevi seen in association with mycosis fungoides

BACKGROUND: Many different tumors have been reported to occur simultaneously as collision lesions. To date, no such events have been reported between mycosis fungoides (MFs) and melanocytic neoplasms. METHODS: Two cases are presented in which patches of MF were superimposed on melanocytic nevi. In addition, 967 biopsies of MF from 411 patients were identified in an 8-year retrospective database search. Patient pathology history summaries were reviewed to identify inflamed nevi, atypical nevi, and melanoma submitted for histologic evaluation from this population. RESULTS: The occurrence of MF in a congenital nevus was associated with a halo phenomenon restricted to the affected region of the nevus in one patient. In the other patient, nests of two morphologies (lymphocytic and melanocytic) in the same biopsy presented a potentially confusing histologic picture. No other cases of MF superimposed on a nevus were identified in 967 biopsies from 411 patients with a histological diagnosis of MF seen over the past 8 years. In this population, 57 biopsies of melanocytic lesions were identified from 28 patients, including three atypical nevi and three melanomas. CONCLUSIONS: The presence of MF superimposed on a nevus is rare and may lead to confounding histologic features or the development of a halo nevus phenomenon.     

Histopathologic features of alopecia areata: a new look

BACKGROUND: A peribulbar lymphocytic infiltrate is the expected histologic feature of alopecia areata, but it is absent in many scalp biopsy specimens. Other diagnostic criteria are needed. OBJECTIVE: To establish the histologic features of alopecia areata in scalp biopsy specimens taken from different types of alopecia areata, using follicular counts to relate biopsy findings to stages of the disease. METHODS: Fifty consecutive new patients with alopecia areata were studied. Four-millimeter punch biopsy specimens were taken from the scalp in areas of recent, active hair loss; old, inactive hair loss; or recent hair regrowth. Specimens were sectioned horizontally. Terminal and vellus-like hairs were counted. Inflammation and fibrosis around lower and upper follicles were rated. RESULTS: The histopathologic features of alopecia areata were not significantly affected by the sex, age, and race of the patient or by the type, percentage of hair loss, total duration, or regression of alopecia areata. The major factor affecting the histopathologic features was the duration of the current episode of alopecia areata. In the acute stage, bulbar lymphocytes surrounded terminal hairs in early episodes and miniaturized hairs in repeated episodes. In the subacute stage, decreased anagen and increased catagen and telogen hairs were characteristic. In the chronic stage, decreased terminal and increased miniaturized hairs were found, with variable inflammation. During recovery, increasing numbers of terminal anagen hairs from regrowth of miniaturized hairs and a lack of inflammation were noted. CONCLUSIONS: The histopathologic features of alopecia areata depend on the stage of the current episode. Alopecia areata should be suspected when high percentages of telogen hairs or miniaturized hairs are present, even in the absence of a peribulbar lymphocytic infiltrate.     

Severe adverse cutaneous drug eruptions: epidemiological and clinical features

Introduction Adverse cutaneous drug reactions (ACDR) are common, and some can be lethal. The aim of our study was to discuss the epidemiological and clinical features of severe ACDR. Materials and methods We retrospectively analyzed 100 cases of ACDR from 1981 to 2007, collected in the Department of Dermatology of the La Rabta Hospital in Tunis, which is located in the north of Tunisia. Severity was defined on three criteria: hospitalization; visceral involvement; and severity markers. Results Characteristics of the 54 included cases were: women (70%); mean age: 44.8 years; responsible drugs: anticonvulsants (28%), antibiotics (28%), and nonsteroidal anti‐inflammatory drugs (15%). The most common dermatoses were maculopapular rash (50%). We observed fever (76%), lymphadenopathy (31.5%), eosinophilia (35%), and visceral involvement (50%). Twelve patients died directly related to the ACDR. Conclusion This study underlines the polymorphous clinical presentation of ACDR and the importance of researching some severity markers, which have important practical implications.     

咪喹莫特诱导的银屑病样小鼠模型的组织学及免疫学特征初步探究

目的:研究咪喹莫特诱导的银屑病样小鼠模型的皮肤组织学及免疫学特征。方法:将20只BALB/c小鼠随机分为造模组和对照组,每组10只。所有小鼠背部剃毛后,造模组小鼠于背部皮肤及单侧耳部每日涂抹共计62.5 mg的5%咪喹莫特乳膏1次,连续7 d,空白组小鼠涂抹等量凡士林。每日记录小鼠PASI评分及耳部厚度,并于末次涂药24 h后处死,取背部皮肤进行多聚甲醛固定,行HE染色及Ki-67免疫组化分析。取脾脏称重,以流式细胞术检测脾脏中的Th细胞亚群。结果:造模组小鼠于第二天逐渐出现红斑、鳞屑、皮肤增厚及耳部肿胀,其PASI评分随造模时间延长而增加。造模组小鼠皮损出现银屑病样病理改变,其表皮厚度明显增加(t=15.12,P<0.001),且Ki-67阳性率明显上升,每个高倍镜视野下阳性细胞数目明显增加(t=10.50,P<0.001)。造模组小鼠脾脏重量和细胞计数较对照组明显增加,且Th1、Th17细胞亚群的比例及绝对计数较对照组明显上升(P值均<0.05),Th2细胞比例及计数无明显变化(P值均>0.05)。结论:咪喹莫特诱导的银屑病样小鼠模型可较好地模拟寻常型银屑病的临床、组织病理和免疫学特征,是一种有效的银屑病模型。     

Recurrent radiation recall dermatitis triggered by radiological procedures in a patient with breast cancer

Radiation recall dermatitis is an acute inflammatory reaction that occurs on previously irradiated skin by usage of chemotherapeutic agents and other triggering drugs. The recall reaction is usually associated with drugs but may also occur following ultraviolet radiation. We report a patient with radiation recall dermatitis, triggered after imaging procedures that involved radiation.