John G. Guccion

Intestinal spirochetosis and acquired immunodeficiency syndrome: ultrastructural studies of two cases.

Two cases of intestinal spirochetosis (IS) with acquired immunodeficiency syndrome are reported. In case 1, a 48-year-old homosexual black man presented with a 1-month history of alternating watery diarrhea and constipation, which dissipated following the removal of two colonic hyperplastic polyps containing IS. In case 2, a 26-year-old homosexual black man presented with a 3-month history of persistent bloody diarrhea and was found to have chronic shigellosis and IS. Pathologic findings of IS were similar in both cases. Basophilic fringes typical of IS covered the surfacing colonic epithelium and consisted of dense growths of spirochetes adherent to and oriented perpendicular to the plasma membranes of the surfacing epithelium. The spirochetes measured 3 to 5 microns in length and 0.2 micron in width, contained four to eight axial fibrils, and closely resembled Brachyspira aalborgi ultrastructurally. These cases are notable because the histopathologic changes of IS were more extensive than generally described. There was involvement of both the right colon and rectum by IS in case 2, and in both cases there was extension of the IS down into the crypts of Lieberkühn, spirochetal invasion of the colonic mucosa, and a conspicuous inflammatory response by macrophages in the underlying lamina propria.

Porocarcinoma of the heel: A case report with unusual histologic features

Eccrine porocarcinoma is an uncommon neoplasm of the intraepidermal sweat gland duct.

Ependymoma: Ultrastructural Studies of Two Cases

Several unusual ultrastructural findings in two ependymomas are reported. In case 1, a grade I ependymoma of the fourth ventricle, there were rosettes, perivascular pseudorosettes, and tumor cells having unusual intracytoplasmic vacuoles by light microscopy. Ultrastructurally, these vacuoles were frequently microrosettes as well as scattered, degenerated cytoplasmic processes of tumor cells. The lumina of some of the microrosettes were bordered by abnormally long and malformed zonulae adherentiae. In case 2, a recurrent grade III ependymoma of the third ventricle, there were rosettes and perivascular pseudorosettes as well as more cellular and anaplastic areas by light microscopy. Ultrastructurally, the cytoplasmic processes of tumor cells in perivascular pseudorosettes contained frequent dense-core vesicles and occasional parallel arrays of microtubules. These structures do not occur in normal mammalian ependymal cells but do occur in the ependymal tanycyte, a related cell that is plentiful in the walls of the third ventricle. Thus some of the tumor cells of this third ventricle ependymoma appear to have differentiated as tanycytes.

Disseminated Blastomycosis and Acquired Immunodeficiency Syndrome: A Case Report and Ultrastructural Study

A 42-year-old, African-American man presented with a 2-month history of weight loss and fever for 2 weeks. Presumptive diagnoses of human immunodeficiency virus infection (HIV) and acquired immunodeficiency syndrome were made on the basis of a CD4 lymphocyte count of 23 lymphocytes/mL. Chest x-ray revealed right paratracheal adenopathy and a miliary pattern. The etiology of the patients pulmonary infection was not known, but tuberculosis was an important consideration. Over 5 days, the pulmonary infection progressed and was complicated by acute respiratory distress syndrome (ARDS), septic shock, and death, despite vigorous antibiotic and supportive therapy. Serologic tests for HIV infection were reported as positive after the patients demise. The etiology of the patients pulmonary infection, ARDS, and sepsis was not known until autopsy study revealed enumerable yeast-like cells of Blastomyces dermatitidis in the extensively consolidated lungs and in disseminated foci of infection in most other major organs. Diffuse alveolar damage was closely associated with the pulmonary blastomycosis. Electron microscopic study of the yeast-like cells of B. dermatitidis in the autopsy lung obtained and fixed 5 days after the patients death revealed excellent preservation of viable organisms.

ORAL HAIRY LEUKOPLAKIA : AN ULTRASTRUCTURAL STUDY AND REVIEW OF THE LITERATURE

A 39-year-old, homosexual, Caucasian man with a 9-month history of acquired immunodeficiency syndrome by reduced CD4 lymphocyte count alone was found to have extensive, asymptomatic, nonremovable, corrugated, white patches on the lateral borders and ventral aspects of the tongue typical of oral hairy leukoplakia (OHL). Histologically, irregular hyperparakeratosis, acanthosis, and clusters of ballooned keratinocytes in the stratum spinosum were present in the biopsied lateral tongue. Some of the superficial ballooned keratinocytes had peripherally beaded nuclei, whereas others had ground glass intranuclear inclusions. Ultrastructurally, the ballooned keratinocytes had three important findings of diagnostic significance. First, frequent herpesvirus nucleocapsids were largely confined to superficial ballooned keratinocytes having marginated and condensed chromatin. In searching for herpesvirus nucleocapsids, the marginated and condensed chromatin was an invaluable marker for cells harboring the virions. Second, the marginated and condensed chromatin frequently had a distinctive punched-out or cribriform appearance. Third, the ground glass intranuclear inclusion bodies consisted of central, medium electron-dense, finely granular material containing frequent herpesvirus nucleocapsids and partially surrounded or capped by prominent, clumped chromatin. The patient died with progressive multifocal leukoencephalopathy 24 months after OHL was diagnosed.

Cytomembranous inclusions in myelodysplastic syndrome.

A 56-year-old African-American man presented with fever of unknown origin and peripheral blood and bone marrow findings of myelodysplastic syndrome (MDS): refractory anemia with an excess of blasts in transformation that subsequently progressed to acute myeloblastic leukemia (AML). Ultrastructural study of two bone marrow specimens having the findings of MDS revealed frequent, large tubuloreticular structures (TRS) in lymphocytes, plasma cells, macrophages, and endothelial cells. Several cylindrical confronting cisternae (CCC) were present in macrophages and an endothelial cell. Two partially developed CCC were present in a plasma cell. TRS and CCC were not observed in eight subsequent bone marrow specimens obtained during the 9-month course of the AML. This is the first reported occurrence of TRS and CCC in MDS. These inclusions are probably related to an unidentified viral infection or possibly to cytokines released by the dysplastic hematopoietic cells.

Sea-blue histiocytes in a patient with lymphoma

A middle-aged man with lymphocytic lymphoma had numerous sea-blue histiocytes in his bone marrow, splenomegaly and thrombocytopenia. Thus, his illness mimicked that of patients with the primary syndrome of the sea-blue histiocyte. However, the paucity of sea-blue histiocytes in his spleen, the absence of neurologic disease, his age and the ultrastructure of his abnormal histiocytes were all evidence for the presence of the acquired syndrome. The pathogenesis of sea-blue histiocytosis and the relationship between acquired cases and the primary syndrome are discussed.

Giant Lamellar Bodies in a Pulmonary MALT Lymphoma: A Case Report with Ultrastructural and Immunohistochemical Studies

A 35-year-old, African-American man presented with a 7-year history of a persistent, enlarging pulmonary infiltrate in the right middle lobe associated with three episodes of right-sided pneumonia, recent 12-lb weight loss, and progressive shortness of breath. The nature of the right middle lobe infiltrate was unclear, but recurrent aspiration pneumonia and carcinoma of lung were important considerations. Exploratory thoracotomy with partial lobectomies revealed a low-grade B-cell lymphoma of mucosa-associated lymphoid tissue (MALT). Clusters of giant lamellar bodies were a unique finding in this lymphoma. Results of ultrastructural and immunohistochemical studies gave support to the views that these inclusions were derived from both products of cellular degeneration and surfactant. The pulmonary lymphoma subsequently spread to the gastric mucosa. The patient is alive with lymphoma 5 years after the initial diagnosis was made.

Malacoplakia of epididymis.

Malacoplakia localized to the epididymis is described. Ultrastructural study revealed the presence of bacterial bodies in phagolysosomes of malacoplakic macrophages. The possible role of the phagocytosed bacteria in the pathogenesis of malacoplakia is briefly discussed.

Papillary Eccrine Adenoma: An Ultrastructural and Immunohistochemical Study

A 45-year-old African American man presented with a small, solitary, nonulcerated cutaneous lesion of the right thigh of many years duration, which was excised. Light microscopically, the lesion consisted of an oval, well-circumscribed, intradermal proliferation of tubules, which were often dilated and lined by a double layer of tumor cells with conspicuous intraluminal papillations. Ultrastructurally, there was evidence of both intradermal eccrine duct and eccrine secretory coil differentiation. Although the majority of tumor cells resembled cells of the intradermal eccrine duct, occasional myoepithelial tumor cells and rare tumor cells having secretory granules and resembling dark mucous cells were indicative of eccrine secretory coil differentiation. The positive immunohistochemical staining for S-100 protein, CEA, EMA, and vimentin supported these ultrastructural findings.