Biomedical subjects
Publications and source records attributed to K L Ho.
A case of malakoplakia is presented which was confined to the renal parenchyma of both kidneys in a thirty-five-year-old woman in whom fatal renal failure developed in three weeks. Bilateral renal malakoplakia is rare, and unlike malakoplakia of the bladder, it behaves as a progressive, destructive, and fatal disease.
Sarcoidosis rarely involves the female genital tract. This report describes a case of sarcoidosis of the uterus that was found by endometrial curettage for menometrorrhagia. Reports of the few previously documented examples of sarcoidosis of the uterus are reviewed with a brief discussion of the differential diagnosis.
Focal myositis is a recently defined, rapidly growing, inflammatory pseudotumor of skeletal muscle. It is characterized by marked myopathic changes of muscle fibers, hypocellular fibrosis of perimysium and endomysium, and an intense inflammatory reaction in the fibrous septa. This report describes the first instance involving the neck muscle of a 40 year old man. A brief discussion of other histologically similar subcutaneous lesions is also presented.
Sarcoma metastatic to the central nervous system is generally considered to be rare. In this report three cases of sarcoma with metastasis to the central nervous system are presented. The case of rhabdomyosarcoma of the lung probably represents the first reported instance of such tumor metastatic to the central nervous system. The case of fibrosarcoma of the thigh is thought to be the first report of metastatic sarcoma with leptomeningeal dissemination. The metastatic brain lesions of the alveolar soft part sarcoma were incidental findings at autopsy. A summary of 22 cases previously reported and a brief discussion of the mode of metastasis of sarcoma, as compared to that of carcinoma, are also presented.
Aneurysms of the pancreaticoduodenal artery are uncommon. Only 24 cases have so far been reported. A case of clinically unsuspected, fatally ruptured pancreaticoduodenal artery aneurysm in a 64-year-old man with a five-day history of mild epigastric pain is reported. A review of the literature and brief discussion of etiologic factors and clinical presentations are also included.
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Subacute necrotizing encephalomyelopathy (SNE) usually appears before the age of 2 years. Variability in its clinical presentation make antemortem diagnosis difficult. The morphologic diagnosis depends on the present of necrotizing lesions with a characteristic distribution within the CNS. We describe a patient with the uncommon adult form of SNE. The pathologic changes are those accepted as diagnostic of the more common infantile SNE, and permit a separation from Wernicke's encephalopathy. In the adult, the disease is thought to be due to a less severe thiamine-related metabolic defect than that of the infantile form. The infrequent clinical recognition in the adult form may be due in part to lack of medical awareness.
Suckling, weanling, and adult HaM/ICR and Swiss-Webster mice were inoculated intraperitoneally with the TC631 and Dowell strains of coxsackievirus B4. Vero cell-inoculated and uninoculated control mice were also studied under code. An intense, necrotizing myopericarditis was produced in suckling mice; it was less severe in weanlings. Myocarditis did not occur when coxsackievirus B4 was inoculated into adult mice. Progressive sclerosis and thickening of all valves in both strains of mice were observed with equal frequency in infected and control mice. There was no evidence that coxsackievirus B4 induced a specific valvular or endocardial lesion.
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Intact peripheral blood elements were found within an intracranial mass, possibly eithern an antemortem subdural hematoma or a postmortem blood clot, removed from a 2200-year-old Egyptian female mummy. Surface topographies of neutrophils and lymphocytes were similar. Some erythrocytes partially retained their biconcave disk shape; others were spherical. Individual platelets exhibited pseudopodia.
Intracytoplasmic lumina (ICL) are rarely described in tumors of the central nervous system. The morphogenesis of ICL remains incompletely characterized. Ultrastructural features of ICL in six ependymomas (one from lateral ventricle, three from fourth ventricle, and two from spinal cord) and three myxopapillary ependymomas of the filum terminale were analyzed. Two types of ICL were identified: ICL with both microvilli and cilia, and ICL with only microvilli. Some ICL also contained granulofibrillary or condensed material. Ciliated ICL were common in ependymomas of the ventricles, whereas nonciliated ICL were frequently seen in the myxopapillary variant. Various stages of formation and development were observed in ciliated ICL. They seemed to originate from distended periciliary cisterns, to enlarge by fusion with cytoplasmic vesicles or other ICL, and subsequently to open into the intercellular space. The last process may be the mechanism by which the intercellular microrosettes are formed. Ciliated ICL have not been described in other neoplasms. They may represent a characteristic ultrastructural feature of ependymomas. The morphogenesis of nonciliated ICL remains unknown. They may represent a degenerative form of ciliated ICL or pseudolumina resulting from invagination of the extracellular space within the cytoplasm.
Association of glioma with AIDS is unusual. Cytomegalovirus (CMV) infection of glioma has not been documented in AIDS or non-AIDS patients. We present the case of a 37-year-old homosexual, HIV positive man who had a history of pneumocystis pneumonia and died of disseminated CMV infection and an anaplastic astrocytoma (5 x 5 x 4 cm) of the left temporal lobe. Part of the tumor was severely infected by CMV as demonstrated by immunohistochemical stain. Intranuclear and intracytoplasmic CMV inclusions were present in the cytomegalic cells whose astrocytic nature was identified by immunostain for GFAP. CMV-bearing cells were scattered throughout the astrocytoma but were rarely seen outside the tumor. CMV-bearing endothelial cells were seen in several capillaries within the tumor. Microglial nodules were scattered within the tumor and some contained CMV-infected cells. Many multinucleated giant cells (MNGC) with circularly arranged small nuclei were present in the infected area of the tumor and some showed fusion with cytomegalic cells. MNGC were absent outside the tumor. CMV ependymitis was not seen. The findings suggest that a) astrocytoma cells are permissive to CMV infection, b) that they may be more susceptible to CMV infection and replication than normal brain tissue, and c) the hyperplastic endothelia and abnormal blood brain barrier of the astrocytoma may facilitate the entry of CMV itno the tumor.
Evaginations of the nuclear envelope containing nuclear material were observed in neoplastic cells of a cerebral primitive neuroectodermal tumor. The possible sequential development of nuclear evaginations included: 1) formation of a segmental naked inner membrane of the nuclear envelope due to loss of the underlying marginal heterochromatin, 2) elevation of the overlying outer nuclear membrane with focal expansion of the perinuclear cistern, 3) outpouching of the inner nuclear membrane forming a small bleb, and 4) protrusion of electron-lucent nuclear material into the bleb forming a nuclear evagination. Some nuclear evaginations were isolated in the cytoplasm and some protruded into the intercellular space. The inner nuclear membrane of the nuclear evagination was devoid of the marginal heterochromatin. Nuclear pores and rupture of membranes with release of the contents of nuclear evaginations into the cytoplasm were not observed. Instead, the nuclear evaginations isolated from the cytoplasm often exhibited degenerative changes with disintegration of their contents and inner nuclear membrane. It is suggested that the nuclear evaginations of the neoplastic cells in the present study may represent a means to eliminate excess nuclear material.
An unruptured hemangioma (vascular malformation) of the choroid plexus of the lateral ventricle in a premature stillborn baby is described. Along the flattened choroid plexus epithelium covering the hemangioma there were small, discrete glial nodules which stained strongly and diffusely for glial fibrillary acidic protein (GFAP). The glial nodules were devoid of surface epithelium and confined within the basement membrane region of the choroid plexus epithelium. GFAP positive cells were not present elsewhere in the choroid plexus. The histogenesis of the glial nodules, whether they have resulted from glial differentiation of reactive choroid plexus epithelium or represented glial heterotopia, remains uncertain.
The presence of heterotopic neuroglial tissue in the cerebral dura mater has not been documented. This report describes three cases of heterotopic neuroglial tissue in the parasalgittal cerebral dura mater found in a study of 257 adult brains, with an incidence of 1.2%. None were associated with developmental abnormalities of the CNS. The heterotopias were isolated and completely encased within the dura mater with no attachment to the leptomeninges. Their number varied from one to nine. They were composed primarily of astrocytes in a glial network and often stained strongly for glial fibrillary acidic protein and S-100 protein. Oligodendrocyte-like cells were noted but nerve cells, ependyma-lined canals and choroid plexus were absent. Dural neuroglial heterotopias are likely developmental malformations and may represent formes frustes of encephalocele.
A comparative study of the ultrastructure of two cases of ecchordosis physaliphora and of two chordomas demonstrated outstanding similarities in the cells composing these two entities. Chordoma cells possessed a more prominent Golgi apparatus, an endoplasmic reticulum-mitochondria complex, plasmalemmal infoldings, nuclear irregularities and a larger extracellular space with abundant matrix, reflecting their expanding neoplastic nature. Ecchordosis cells had nuclear inclusions, dense-core membrane-bound granules and subcytoplasmalemmal linear densities, not previously described. Both ecchordosis and chordoma cells have morphologic features of both epithelial and mesodermal character. This study supports the concept that chordomas arise from heterotopic notochordal remnants in the cranio-vertebral canal.
In this report, primary Clostridium perfringens meningitis, a rare condition, is described in a 62-year-old man who developed fatal clostridial meningitis following surgical evacuation of a subdural hematoma. This is the third case report of clostridial meningitis as a complication of craniotomy. Clostridial infection should be considered in any patient with meningitis with a history of surgical intervention, or head injury, even if only slight.