Acute idiopathic interstitial myocarditis: case report with special reference to morphological characteristics of giant cells.

Necropsy findings of an acute fatal case of idiopathic interstitial myocarditis were reported. The patient was a 33 year old housewife who had acute cardiac failure on the sixteenth day after the onset of the disease. Necropsy showed important pathological changes confined to the heart. Both ventricles were affected by confluent granulomas with an ill defined patchy appearance. Histologically these lesions consisted of round cells, histiocytes, eosinophils and myogenic giant cells. The findings were compatible with those of interstitial myocarditis associated with a proliferation of giant cells. Both atriums were also affected to a minor extent, detectable only by histological examination. Electron microscopy and cytochemistry showed that most giant cells noted in the lesion showed myofibrils and primary lysosomes in the cytoplasm. Giant cells were positive for myoglobin. Though the macrophage origin of the giant cell in this disorder has been emphasised in a recent report, these cytological results suggest that giant cells observed in the cardiac granulomatous lesions of this case were mainly myogenic in origin.     

Malignant sarcomatoid mesothelioma of the pleura: a histological and immunohistological study of a case

The authors describe the case of a 70 year-old asymptomatic female, who showed nodular pleural growths at an occasional chest roentgenogram. Histological examinations and laboratory findings excluded the possibility of an inflammatory granulomatous process, but they did not allow differentiation between malignant sarcomatoid pleural mesothelioma and malignant fibrous histiocytoma. Only at immunohistochemistry was the differential diagnosis made. In fact, the co-expression of vimentin and cytokeratins by neoplastic cells, along with their negativity for macrophage markers strongly supported the hypothesis that the neoplastic growth originated from subpleural mesenchymal stem cells.     

Post-infantile giant cell hepatitis: histological and immunohistochemical study.

AIM--To determine the composition of the inflammatory infiltrate and to check for the presence of cytomegalovirus (CMV) and Epstein-Barr virus (EBV) in nine cases of post-infantile giant cell hepatitis. METHODS--The clinical, serological, and histological features of the nine cases were reviewed. Immunohistochemistry was used on liver biopsy specimens from six cases to: (i) characterise the lymphocytic infiltrate; (ii) assess the monocyte/macrophage response; (iii) detect "activated" perisinusoidal cells; and (iv) detect CMV and EBV antigens. Electron microscopic examination was carried out in two cases. RESULTS--Four patients had serological features suggestive of autoimmune chronic active hepatitis; in the other five cases the aetiology was obscure. Two patients presented with neurological symptoms. Hepatitis resolved completely in one patient; two patients showed clinical improvement; and one remained stable. Cirrhosis developed in three patients, one of whom proceeded to liver transplantation, and three patients died. Portal inflammation was present in all cases and lymphocytic piecemeal necrosis in eight cases, but intra-acinar inflammation associated with hepatocyte necrosis was observed in only five cases. The inflammatory infiltrate was composed predominantly of T lymphocytes; an increase in monocyte/macrophage cells was also observed. Mallory bodies, often with associated neutrophilic infiltrate, were present in four cases, and bilirubinostasis was a feature in four cases. "Activated" perisinusoidal cells were present, especially in relation to areas of inflammation, necrosis, and fibrosis. There was severe fibrosis or cirrhosis in five cases. Paramyxoviral nucleocapsids were not seen in the two cases examined ultrastructurally. CONCLUSIONS--Post-infantile giant cell hepatitis should be viewed as a heterogeneous clinical and aetiological entity encompassing cases of hepatitis with extensive giant cell hepatocyte transformation.     

Calcium overload in human giant cell myocarditis.

Myocardial calcium overload was observed in a patient with giant cell myocarditis. The myocardial calcium content estimated by atomic absorption spectrophotometry amounted to 120 mEq/kg dry weight, and the von Kossa stain disclosed multiple foci with patchy calcifications of myocardial fibres. Cytochemical examination of the ultrastructural calcium localisation using the phosphate-pyroantimonate method showed considerable variation in the subcellular calcium distribution. In normal myocytes calcium precipitates were confined to the inner leaflet of the sarcolemma, T-tubules, intercalated disks, and sporadically to mitochondria. In contrast, extensive calcification of mitochondria and loss of sarcolemmal calcium was evident in necrotic myocytes. A number of grossly normal myocytes also showed an increase of calcium precipitates in slightly swollen mitochondria. These findings suggest that myocardial calcium overload in this case started in viable myocytes and was not merely a secondary phenomenon occurring after cell death.     

Centrilobular fibrosis: a novel histological pattern of idiopathic interstitial pneumonia

The classification of idiopathic interstitial pneumonias (IIP) is still under debate. In this context, we observed in some of our patients with a clinical and radiological diagnosis of IIP a different histological picture with an aggressive centrilobular scarring centered in the bronchiolar epithelia, but involving the surrounding parenchyma, which underwent extensive remodeling. We hypothesized that this pattern is a form of IIP that could be separated out histologically from the previously described patterns, in particular from usual interstitial pneumonia (UIP) and non-specific interstitial pneumonia (NSIP). Forty-nine patients with clinical and radiological diagnosis of IIP and open-lung biopsies were retrospectively selected from 1982 to 1998. The biopsies were reviewed according to the following criteria: derangement of lobular architecture, temporal homogeneity and subpleural or bronchocentric distribution of the lesions, fibroblast foci, bronchial epithelium necrosis and regeneration, exposure of the basal membrane, squamous metaplasia, basophilic intraluminal contents, and foreign bodies within the remodeling airspaces. Three groups were found: UIP (24 patients), NSIP (13), and a third that we named centrilobular fibrosis (CLF) (12). All histological parameters were significantly different among the three groups (p < 0.001). CLF is a specific, homogeneous, and recognizable histological pattern of IIP, and can be isolated from UIP and NSIP.     

An autopsy case of giant cell myocarditis probably due to a non-steroidal anti-inflammatory drug

An autopsy case of giant cell myocarditis (GCM) in a 74-year-old woman is presented. She suffered from hepatic dysfunction, skin eruption and disseminated intravascular coagulation due to the side-effects of a non-steroidal anti-inflammatory drug. After admission, heart failure progressed rapidly, and the patient died suddenly. At autopsy, her heart was slightly enlarged and the heart muscle was thickened with many small whitish nodules. She was diagnosed with GCM because of the infiltration of multinuclear giant cells, histiocytes, eosinophils and lymphocytes into the heart. We did not find any similar lesions in any other organs. Giant cell myocarditis, the etiology of which is not defined, is a rare disease with unfavorable prognosis. This case suggests the possibility of drug-induced GCM.     

Ependymoblastoma: a histological, immunohistological and ultrastructural study of five cases

Five ependymoblastomas were studied by means of routine histological techniques, immunohistology and electron microscopy. The tumours were characterized histologically by medium sized, poorly differentiated cells with round or oval nuclei frequently in mitosis and by ependymoblastic rosettes. Reactions for cytokeratin and neurofilament were negative and tubular material positive for glial fibrillary acidic protein was scanty. All five tumors demonstrated positivity for vimentin and S-100 protein. Electron microscopy showed poorly differentiated cells with high nucleo-cytoplasmic ratio and scanty cytoplasmic organelles. Sparse rosettes were present and the cells were united by junctional complexes. Frequent rudimentary or incomplete cilia, a few basal bodies and a few short intercellular glial-like filaments were seen. Features differentiating ependymomas and anaplastic ependymomas from ependymoblastomas are discussed and the need for a definite category separating ependymoblastomas from the former tumours is emphasized.     

Hyperacute graft rejection during heart transplantation for giant cell myocarditis: A case report

We report the case of a patient with giant cell myocarditis who was bridged to transplantation with mechanical circulatory support and developed a fatal perioperative hyperacute rejection. The patient had received abundant transfusions that had raised her anti-HLA antibody titers. The cross-match test was positive. No pre-transplantation immunosuppressive therapy had been administered given concomitant infection. The severity and acuteness of the rejection in this case likely reflect the combined effect of preformed anti-HLA antibodies in the context of an active organ-specific immune process at the time of transplantation. This case raises the questions of the need for intensive immunosuppressive therapy before transplantation in giant cell myocarditis and of the management of patients with positive cross-match in the context of a giant cell myocarditis.     

A histological and immunoenzymatic study on the histogenesis of "giant cell tumor of bones"

We carried out a prospective histologic and immunoenzymatic study, using lysozyme and AI-antichymotrypsin, of 15 well documented cases of giant cell tumors of bones. The histologic appearance of the majority of the tumors was characterized by great pleomorphism. The predominant histologic patterns could be classified as either fibroblastic or histiocytic. Mitoses were seen exclusively on stromal mononuclear cells. All tumors showed positive marking with both lysozyme and AI-antichymotrypsin. The enzymatic activity was more pronounced in areas of conventional histology and appeared as coarse orange-brown granules in the cytoplasm of many mononuclear and multinucleated giant cells. Enzyme-positive cells were less frequently found in fibroblastic areas of the tumor and especially in areas with minimal differentiation. The results indicate that giant cell tumor of bones may result from the neoplastic proliferation of mononuclear cells which in many areas of the tumor differentiate to either fibroblasts or histiocytes. Thus, giant cell tumor of bones may be analogous to fibrohistiocytic tumors of soft tissues.     

Successful therapy of cyclosporin A in a case with idiopathic interstitial pneumonia]

Seventy-one-year-old woman was visited to our hospital because of dry cough and dyspnea on effort. Fine crackle was audible on both lower lung fields. Joints and skin were normal. Laboratory examination revealed elevation of serum LDH and CRP level. Both anti-nuclear antibody and Jo-1 antibody were negative. Blood gas analysis showed hypoxia after exercise. Chest X-ray film showed reticular shadow in both lower lung fields. Chest CT finding showed patchy area of ground glass attenuation, air-space consolidation, and reticular shadow. Scintigram showed diffuse uptake of Gallium-67 in both lung. Transbronchial biopsy specimen revealed alveolar wall thickness, lymphocyte infiltration and swelling of type II pneumocytes. Bronchoalveolar lavage fluid analysis revealed elevation of CD4/CD8 ratio. She was given a diagnosis of idiopathic interstitial pneumonia. Combination therapy of cyclosporin A and steroid was performed. After therapy, her chest CT findings and her data of pulmonary function test were improved. Then therapy of cyclosporin A was continued and dose of prednisolone was gradually decreased. After that, she was suffered from respiratory tract infection. After administration of antibiotics and cyclosporin A, she was getting well without acute exacerbation of interstitial pneumonia. Since then, she was treated with cyclosporin A only and her pulmonary function test data were gradually improved more. It suggests that cyclosporin A may be useful for the treatment of idiopathic interstitial pneumonia.     

Granular cell tumours revisited. An immunohistological and ultrastructural study

Twenty-five granular cell tumours were stained with a panel of antibodies to histiocytic, muscle, neural, neural crest, epithelial and endothelial markers. Electron microscopy was also performed in six cases. Twenty-four of the cases were similar morphologically and immunocytochemically. One case with features of an endothelial origin is described. The present study strongly supports the viewpoint that granular cell tumours are a distinct entity rather than being the common appearance of a group of lesions of differing histogenesis. Origin from a neural crest-derived peripheral nerve-related cell is favoured.     

Microphotometric quantitation of enzyme activities in giant cell tumor of bone. A case study

In a proliferating giant cell tumor of bone the activities of tartrate-resistant acid phosphatase (acPase) and of NADH-tetrazolium reductase were demonstrated by enzyme histochemical methods. Quantitative microphotometry made it possible to determine the relative enzyme activities per given volume unit in the cytoplasm of giant cells of several sizes. The activity of tartrate-resistant acid phosphatase increases with increasing cell size, whereas the activity of tetrazolium reductase will decrease in proportion. This coincidence of high acPase activity and low tetrazolium reductase activity in larger giant cells is interpreted as an expression of degenerative change.     

Breast carcinoma developing in patients on hormone replacement therapy: a histological and immunohistological study

AIM: To study the histopathological features of breast carcinoma developing in postmenopausal patients on hormone replacement therapy (HRT). METHODS: The sample comprised 60 patients with invasive breast carcinoma including 31 who had received HRT at or shortly before presentation, and 29 who had not. Details concerning their tumour size, histological type and grade, lymph node status, and oestrogen and progesterone receptor status were compared. Immunoperoxidase staining for Bcl-2, p53, and E-cadherin was carried out on paraffin sections of all 60 patients. The results were then statistically analysed. RESULTS: Tumours detected in HRT patients were significantly smaller (mean 17 mm v 25 mm; p = 0.0156) and of a lower histological grade (p = 0.0414) than those detected in non-HRT patients. The incidence of invasive lobular carcinoma was slightly higher in HRT patients (19% v 14%). Immunohistologically, 87% of HRT tumours were Bcl-2 positive (compared with 79% in the control group), 29% were p53 positive (45% in the control), and 48% were E-cadherin positive (72% in the control group). Although the differences were not statistically significant there was a trend towards higher incidence of p53 negative and E-cadherin negative tumours in HRT patients. CONCLUSIONS: Breast carcinomas detected in patients on HRT have a significantly higher incidence of two favourable prognostic features (small size and a low histological grade). They also show a trend, statistically not significant, of being p53 negative and E-cadherin negative; this may be related to the slightly higher incidence of invasive lobular tumours in these patients.     

Metastatic thymoma: a case report and immunohistological analysis.

A patient with metastatic lymphocyte predominant thymoma was studied and an immunohistological analysis of frozen and paraffin sections was performed. The immunophenotype of the lymphoid cells was similar to that of primary thymomas and T cell lymphoblastic lymphomas. The epithelial cells reacted with an anticytokeratin monoclonal antibody. The results have diagnostic implications for the histopathologist using immunohistochemistry as a diagnostic aid and it is concluded that a panel of monoclonal antibodies against both lymphoid and epithelial markers should be used for immunohistological typing of tumours of uncertain histogenesis.