Darius R. Mehregan

Urticarial vasculitis: A histopathologic and clinical review of 72 cases

BACKGROUND Urticarial vasculitis is a subset of vasculitis characterized clinically by urticarial skin lesions and histologically by necrotizing vasculitis. OBJECTIVE A review of patients with urticarial vasculitis was undertaken to further characterize the clinical and histologic findings and to differentiate this disorder from urticaria and other types of cutaneous vasculitis. METHODS Seventy-two cases of biopsy-proven urticarial vasculitis were selected for a review of medical records, laboratory data, and histologic findings. Fifty cases of simple urticaria were also reviewed for purposes of comparison. RESULTS Systemic symptoms in patients with urticarial vasculitis included angioedema in 30 patients (42%), arthralgias in 35 (49%), pulmonary disease in 15 (21%), and abdominal pain in 12 (17%). Twenty-three patients (32%) had hypocomplementemia. Forty-six of 72 patients (64%) had lesions that lasted more than 24 hours, 23 of 72 (32%) had painful or burning lesions, and 25 of 72 (35%) had lesions that resolved with purpura. Sixteen biopsy specimens from the 23 patients with hypocomplementemia showed dermal neutrophilia in addition to the perivascular infiltrate. Of the 23 patients with hypocomplementemia, 20 (87%) had fluorescence of the blood vessels and 16 (70%) had fluorescence of the basement membrane zone as determined by routine direct immunofluorescence. CONCLUSION Patients with hypocomplementemia were more likely to have systemic symptoms such as urticaria that resolved with purpura, arthralgias, abdominal pain, and chronic obstructive pulmonary disease. The histologic pattern associated with hypocomplementemia is interstitial neutrophilic infiltrate of the dermis and an immunofluorescent pattern of immunoglobulins or C3 in the blood vessels and along the basement membrane zone.

Wells’ syndrome: a clinical and histopathologic review of seven cases

Wells’ syndrome, or eosinophilic cellulitis, is characterized clinically by an acute dermatitis resembling cellulitis, which evolves into violaceous plaques that resolve spontaneously without scarring. The histopathologic features are dynamic, starting with dermal edema and infiltration of eosinophils, the development of “flame figures,” and finishing with the appearance of phagocytic histiocytes. We present the clinical and histopathologic features of seven cases of eosinophilic cellulitis.

Chronic Lupoid Leishmaniasis: Evaluation by Polymerase Chain Reaction

BACKGROUND The cutaneous lesions in chronic lupoid leishmaniasis resemble those of lupus vulgaris, both clinically and histologically. The differential diagnosis is difficult and may depend on the detection of a few Leishmania amastigotes in the histologic sections, the growth of the promastigotes in cultures, or the identification of amastigotes by other techniques. Polymerase chain reaction was used to detect Leishmania amastigote DNA in tissue samples obtained from 65 patients with chronic lupoid leismaniasis, and the results were confirmed by Southern blot analysis. OBSERVATIONS The histologic findings of a predominantly epithelioid cell granuloma surrounded by lymphocytic infiltrate in chronic lupoid leishmaniasis are very similar to those observed in lupus vulgaris. Extensive histologic examination of the sections in this series revealed occasional macrophages containing a few amastigotes in only 12 cases. Cultures in NNN medium yielded Leishmania promastigotes in 20 cases. Polymerase chain reaction studies using a Leishmania-specific primer identified Leishmania DNA in 30 of 63 cases, and those using a Mycobacterium tuberculosis primer were found to be negative for mycobacteria in 47 cases tested, including 11 cases with a positive tuberculin skin reaction. CONCLUSIONS The histologic findings in chronic lupoid leishmaniasis resemble those of lupus vulgaris. Polymerase chain reaction studies were useful in identifying amastigotes in 30 (47.6%) of 63 cases. This study confirms the presence of DNA molecules of Leishmania amastigotes in samples of formalin-fixed, paraffin-embedded granulomatous tissue obtained from patients with chronic lupoid leishmaniasis.

Intertriginous granular parakeratosis

An unusual form of parakeratosis localized to the axillae has been previously described in the literature as axillary granular parakeratosis. We report an additional 4 cases, including one that was isolated to the inguinal region. The same histopathologic changes of papillomatosis, acanthosis, and parakeratosis with retention of keratohyalin granules were found in all 4 cases. In the future, we suggest that this entity be designated as intertriginous granular parakeratosis to reflect the newly recognized pattern of distribution. Three separate reports1-3 have described 8 cases of a distinct cutaneous condition known as axillary granular parakeratosis. We describe an additional 4 cases, including the first documented case outside of the axillae (ie, within the groin).

Paraneoplastic pemphigus : a subset of patients with pemphigus and neoplasia

We reviewed the clinical, histologic, and immunofluorescence features of 20 patients with pemphigus and neoplasia and compared them will a control group of 17 patients with pemphigus without neoplasia. Patients with neoplasia were divided according to clinical, histologic, and immunofluorescence findings into those with paraneoplastic pemphigus syndrome (12 patients) and those with classic pemphigus vulgaris or pemphigus foliaceus with neoplasia (8 patients). The histologic findings in patients with paraneoplastic pemphigus included acantholysis, interface dermatitis, spongiosis, and satellite keratinocyte necrosis. Histologic findings in the 8 patients with classic pemphigus and neoplasia included acantholysis and spongiosis. Direct immunofluorescence in both paraneoplastic pemphigus and pemphigus with neoplasia showed IgG staining of cell‐surface proteins (intercellular substance) and deposition of immunoglobulin at the basement membrane one. Indirect immunofluorescence with rat bladder substrate was used to differentiate paraneoplastic pemphigus from classic pemphigus. Circulating IgG anti‐cell‐surface protein antibodies were detected in 4 patients with paraneoplastic pemphigus syndrome; they were absent in 2 patients with pemphigus and neoplasia. Immunoprecipitation of sera from the 4 patients with epithelial staining showed the complex of bands identified in studies of paraneoplastic pemphigus syndrome. We conclude that paraneoplastic pemphigus syndrome has distinct clinical, histologic, and immunologic features that differentiate it from classic pemphigus with underlying neoplasia.

Axillary granular parakeratosis

We report two cases of axillary granular parakeratosis, which is a unique eruption involving the axilla that has distinctive histopathologic features. Both of our patients had slightly pruritic, hyperpigmented patches in the axilla. The biopsy specimens revealed severe compact parakeratosis with maintenance of the stratum granulosum and retention of keratohyalin granules throughout the stratum corneum, which was markedly thickened and measured between 90 to 185 microns. The exact etiology is not known, but this conditions is believed to represent a contact reaction to an antiperspirant or deodorant.

Sebaceous epithelioma: A review of twenty-one cases

BACKGROUND Sebaceous epithelioma is a benign tumor that must be differentiated from basal cell carcinoma and other appendageal tumors. OBJECTIVE Histologic and clinical findings were reviewed in 21 patients with sebaceous epitheliomas. METHODS Twenty-one cases of sebaceous epithelioma collected during a 5-year period were reviewed. RESULTS The tumors appeared as yellow to flesh-colored papules, most often on the face and neck. They consisted of basaloid cells with foci of sebaceous differentiation. Cystic spaces formed by holocrine degeneration or simulating sebaceous duct lining were common findings. Patients with sebaceous epitheliomas were more likely than the general population to have an internal malignancy. CONCLUSION Patients with sebaceous epithelioma should be examined for an underlying malignancy.

Molecular diagnosis of basal cell carcinoma and other basaloid cell neoplasms of the skin by the quantification of Gli1 transcript levels

Background:  Distinguishing basal cell carcinoma (BCC) from other benign and malignant skin tumors is sometimes a difficult task for the pathologists. Because the activation of hedgehog signals and the up‐regulation of its critical transcriptional factor Gli1 are well documented in BCC, a molecular technique measuring Gli1 transcripts may aide the diagnosis.

Epithelioid cell histiocytoma: A clinicopathologic and immunohistochemical study of eight cases*

BACKGROUND Epithelioid cell histiocytomas histologically resemble the intradermal form of Spitz nevus. OBJECTIVE We have studied eight patients with epithelioid cell histiocytoma. METHODS In addition to the routine stains, histologic sections were prepared by immunohistochemical techniques for S-100 protein, HMB-45, vimentin, alpha 1-antitrypsin, and common leukocyte antigen. RESULTS Epithelioid cell histiocytoma is characterized by proliferation of angulated epithelioid cells with abundant eosinophilic cytoplasm. Immunostaining for S-100 protein and HMB-45 were negative. The majority of cells had positive reactions to staining for vimentin and alpha 1-antitrypsin. Approximately 20% to 25% of cells also gave positive reactions to common leukocyte antigen. CONCLUSION Immunostainings are useful in the differential diagnosis of epithelioid cell histiocytoma from the intradermal form of Spitz nevus.

Juvenile hyaline fibromatosis: a case report and review of the literature.

Background  Juvenile hyaline fibromatosis (JHF) is a rare, inherited condition characterized by tumor‐like growth of hyalinized fibrous tissue on the head and neck, joint contractures, and gingival hypertrophy. There may be marked clinical heterogeneity.