Sumi Mitsudo

Pathology of Intestinal Ischemia

Intestinal ischemia produces a spectrum of gross and microscopic pathologic changes that range from transmural necrosis to reversible mucosal injury. Depending on the stage at which tissue is examined, findings may reflect the acute injury or reparative changes. This article reviews the diagnosis of the pathologic findings in differential intestinal ischemia.

Malignant mesothelioma of the tunica vaginalis testis: Report of first case with preoperative diagnosis

The cytologic, histologic and ultrastructural features of a malignant carcinomatous mesothelioma of the tunica vaginalis testis in a 30‐year old patient are described. This is the first such case with preoperative diagnosis by cytologic examination of hydrocele fluid and the second with documented history of exposure to asbestos. The identity of the tumor was confirmed by a positive immunoperoxidase reaction directed against mesothelial cells. A review of the previously described ten cases is presented.

Vascular ectasias of the right colon in the elderly: A distinct pathologic entity

Vascular ectasias (angiodysplasias, arteriovenous malformations) of the cecum and ascending colon are a frequent cause of lower intestinal bleeding in the elderly that has been overlooked by clinicians and pathologists. Their nature and etiology have been poorly understood until recently. This article reviews the previous literature and presents a complete and detailed description of these lesions based on the examination of 87 areas showing vascular ectasia from 26 colons. Their morphology spans a spectrum from small focal early lesions to multiple large late lesions. The early lesions are characterized by markedly dilated, large, tortuous submucosal veins with minimal dilatation of their tributaries in the mucosa. The late lesions showed further dilatation of submucosal veins and venules and extensive replacement of the overlying mucosa by racemose collections of dilated and thin walled venules and capillaries, three of which demonstrated rupture into the colonic lumen. The pathology of these lesions is considered to be specific enough to establish vascular ectasias of the colon as a distinct entity.

Chronic Idiopathic Hyperphosphatasia Associated with Pseudoxanthoma Elasticum

Chronic idiopathic hyperphtsphitasia is a rare disease of childhtod characterized by generalized cortical thickening of the long bones and skull, resulting in marked bone deformities, and by a sustained elevated serum alkaline phosphatase value. The roentgenographc and pathological findings in this disease were indistinguishable from adult Pagets disease of bone. The associated pseudoxanthoma elasticum in the presented case may reflect a common underlying defect in these two diseases.

Cytomegalovirus colitis in acquired immune deficiency syndrome: Radiologic spectrum

Six cases of cytomegalovirus (CMV) colitis are described. The radiographic manifestations of this colitis are nonspecific and usually mimic the findings of ulcerative colitis with diffuse mucosal ulceration or granulomatous colitis with aphthous ulceration and skip areas. Terminal ileal involvement was noted in 1 patient. Nonspecific edema was present in 2 other cases. One patient demonstrated unusual cecal and ascending colonic nodularity due to pseudomembranes and, in another, large flat discrete ulcerations were identified. Angiography, in 1 case, demonstrated marked hypervascularity and identified a site of hemorrhage in the ascending colon.With the radiographic identification of colitis in an immunocompromised patient, particularly a patient with acquired immunodeficiency syndrome (AIDS), CMV colitis must be strongly considered in the differential diagnosis. Endoscopic biopsy is the most effective method of establishing the diagnosis.

Nasopharyngeal teratoma in the neonate

Nasopharyngeal teratomas are rare neoplasms, often presenting as neonatal airway obstruction. A case is presented of a full-term neonate with a mass which filled the oropharynx, nasopharynx and the entire left nasal cavity and extended through the left nares. Airway obstruction necessitated orotracheal intubation immediately after delivery. Cerebrospinal fluid rhinorrhea was suggested and computerized tomography was initially interpreted as a nasoethmoidal encephalocele. After a craniotomy failed to reveal a dural defect, the mass was completely removed via the nose and nasopharynx. The infant was extubated and had an uneventful recovery. This case illustrates the problem of confusing a teratoma for an encephalocele and demonstrates a pitfall in the interpretation of computerized tomography of these lesions.

Simulation of colonic carcinoma by ischemia.

Nine cases of colonic ischemia are presented in which an initial diagnosis of carcinoma was made from roentgenographic, endoscopic, or intraoperative appearance of the lesion. The clinical features were insufficient to differentiate colonic ischemia from carcinoma. In 7 patients a barium enema was interpreted as, or consistent with, carcinoma. In 3 of these patients colonoscopy also suggested malignancy. In 2 patients, endoscopy suggested a neoplasm but no barium enema was performed. Endoscopic biopsies when performed were negative for malignancy. Three patients were considered to have cancer from the gross appearance of the lesion at laparotomy. Routine use of both barium enema and colonoscopy in patients with suspected colonic neoplasms will usually identify the ischemic nature of lesions incorrectly diagnosed by one technique or the other. In the uncommon patient in whom both studies suggest a neoplasm, but biopsy specimens are negative for tumor, repeat studies 7-10 days later may identify the evolving nature of ischemic lesions and obviate the need for surgery. When no changes are seen, prompt laparotomy is indicated.

BCNU (1,3‐Bis‐(2‐chloroethyl)‐1‐nitrosurea) lung. Drug‐induced pulmonary changes

The occurrence of pulmonary disease associated with long‐term BCNU therapy is reported in two patients treated for astrocytoma grade II whose clinical presentations of pulmonary complications and corresponding tissue alterations showed striking differences. One patient presented with a dramatic, fulminating, and rapidly fatal pulmonary disease. His lungs revealed atypical proliferation of pneumocytes, moderate interstitial inflammation, fibrosis and intra‐alveolar hyalin membranes. The second patient presented with slowly progressive dyspnea, ultimately leading to death secondary to severe diffuse alveolar septal fibrosis. Individual differences in response to toxicity are suggested and discussed.

Extraperitoneal pelvic meconium extravasation in a newborn infant

MECONIUM PERITONITIS is a well known clinical enti ty resulting from the antenata l , in t rapar tum, or early postnatal perforat ion of the boweU The course of this sterile chemical and foreign body peritonitis may be completely benign, or dea th may occur in utero or shortly a f te r bir th from the under lying cause or f rom complicat ions of the peritonitis. To our knowledge, extraperi toneal pelvic mecon ium extravasat ion has not been reported.

Lung lymphocytes in bleomycin-induced pulmonary disease

Previous studies have not clearly defined the role of cell-mediated immunity in bleomycin-induced lung injury. In this report the functional activity of T lymphocytes obtained from minced lung preparations, bronchoalveolar lavage, and blood of rabbits treated with bleomycin was examined in cell proliferation and cell-mediated cytotoxicity assays. Four days after instillation of bleomycin (10 units/kg) into the right lung, histologic examination revealed mononuclear cell interstitial infiltrates and alveolar exudates. Right lung bronchoalveolar lavage (BAL) cell counts were similar in both groups, but the percentage of lymphocytes and neutrophils was elevated in bleomycin-treated groups (25% vs. 7% and 35% vs. 0% respectively;p<0.05). Spontaneous proliferation of cultured BAL and blood lymphocytes was similar in bleomycin-treated rabbits and controls. After 24 h of incubation with interleukin-2 (IL-2), BAL lymphocytes from bleomycin-treated rabbits had nearly a 4-fold greater proliferative response than lymphocytes from untreated rabbits. Concanavalin-A-dependent cell-mediated cytotoxicity (CDCMC) assays were performed to evaluate cytolytic lymphocyte activity. Spontaneous CDCMC activity was not detected in BAL fluid or in blood lymphocytes from either treated or control animals. After 24 h of incubation with IL-2, significant CDCMC activity was detected in lung lymphocytes from bleomycin-treated animals, but not in lung lymphocytes from control animals. These results indicate that stimulated lymphocytes are present in the lungs of rabbits 4 days after exposure to bleomycin.