Biomedical subjects
Publications and source records attributed to J V Pitha.
A 74-year-old man had sustained a penetrating lead pencil injury to his right lower leg at the age of fifteen. A dark gray macule occurred that remained unchanged for fifty-eight years. An enlarging black nodule appeared in this area, simulating a melanoma, when the patient was seventy-three years old. Histologic examination revealed exogenous pigment and a foreign body reaction.
A blinded, retrospective study of histological sections from ten hydrocarbon-exposed and twenty unexposed nephrectomized renal cell carcinoma cases was conducted to evaluate the histopathologic features present in the apparently normal kidney parenchyma removed with the tumor. Tissue sections from each of the thirty cases were independently reviewed by three consulting pathologists and scored using well defined criteria. Occupational hydrocarbon exposure indices were developed by a team of industrial hygienists and applied to the detailed occupational history of each exposed case. A positive correlation was observed between age and the total renal pathology score (rs = .40, p less than .03). No correlation was found between indices of occupational hydrocarbon exposure and renal pathology scores among exposed cases. No significant differences in renal pathology scores were noted when exposed cases were matched to unexposed cases by age, sex, and race. These results are limited by the inclusion of only cases with historical hydrocarbon exposures. It is recommended that a follow-up study be conducted, utilizing sensitive quantitative methods, to define what, if any, cytopathologic renal effects occur in conjunction with current occupational exposures to hydrocarbons.
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Definite lesions of arteriolar capillaries have been demonstrated in early amyloid lesions of mice. Pathologic changes include multiple endothelial gaps, the loss of an identifiable basal lamina, variable degrees of endothelial alteration, and the presence of the developing amyloid lesions surrounding the affected vessels. Despite these changes, the vessels remain functional part of the local microcirculation as demonstrated by intravascular injection of electron dense markers. These structural changes of arteriolar capillaries explain the presence of circulating plasma as a constant and major component of the early amyloid lesions in these animals and on this basis may determine the time of onset and site of formation of the lesions. The vascular injury appears to be caused by immunologic reactions to injected foreign antigens which gain a close relation to the structures of these vessels.
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A 56-year-old black man with nonendemic adult T-cell leukemia is reported, who presented with severe hypercalcemia and leukemic leptomeningeal infiltration but had no evidence of bone marrow involvement. His malignant cells were characterized by light and transmission electron microscopy, cytogenetics, and flow cytometry. The cells demonstrated the deeply indented or convoluted nuclei characteristic of endemic human T-cell lymphoma virus-associated cases. Surface phenotyping indicated the cells' origin to be from the mature, helper/inducer subset of T-lymphocytes. However, there was no clinical or laboratory evidence that the malignant cells retained immunoregulatory function. The clinical and immunologic features of this and other nonendemic cases are compared with those of patients from the endemic regions of Japan, the Caribbean islands, and the southeastern United States.
Computed tomography (CT) of the adrenal glands was performed on seven patients who had histologically proved disseminated histoplasmosis. All seven patients showed some degree of adrenal gland abnormality. The range of CT findings included minimal enlargement with faint flecks of calcium, moderate enlargement with focal low attenuation nodules, and massive enlargement with large areas of necrosis or dense calcification. The changes in each patient were bilateral and symmetrical. Adrenal gland shape was usually preserved. Findings of percutaneous adrenal biopsy, which was performed under CT guidance, made the diagnosis in one patient. Five of seven patients had adrenal insufficiency. We conclude that the diagnosis of disseminated histoplasmosis should be considered in any patient who has bilateral adrenal gland enlargement and who resides in an endemic area, especially if there is evidence of adrenal insufficiency, and that CT is superb for the assessment of adrenal gland morphology in this disease, and CT-directed biopsy is the recommended method of confirming the diagnosis in difficult cases.
A report of acute myelomonocytic leukemia following successful therapy for oat cell carcinoma is presented. The patient had been treated with extensive cytotoxic and radiation therapy, and was without clinical evidence of disease at one year follow-up. Eighteen months later, a peripheral smear revealed numerous blasts with monocytoid characteristics. This unusual presentation is discussed and compared with several other cases appearing in the recent literature.
This report describes a patient who suffered rupture of the anterior wall of the left ventricle following an acute myocardial infarction and survived for 12 days before dying from cardiac tamponade. Rupture of the heart presented as an asymptomatic pericardial effusion.
A study of tumor incidence and tumor growth rates in 7,12-dimethylbenz(a)anthracene-treated female Sprague-Dawley rats fed different types and amounts of dietary fat indicates that the difference in tumor incidence may be a reflection of marked differences in the growth of neoplastic clones to a palpable size within the time frame of the study. In addition, the observation is made that some antioxidants which inhibit tumor development in animals fed commercial rations are not effective when given in purified diets.
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A case of subcutaneous fat necrosis as the initial manifestation of an attack of acute pancreatitis is presented. The accompanying features of respiratory distress syndrome, leukemoid reaction, shock, pleural effusions, and arthritis due to necrosis of periarticular fat are described. Autopsy findings are pancreatic pseudocyst, serofibrinous peritonitis, pleuritis, and pericarditis and fat necrosis not only in the subcutaneous fat but also in the pericardial, pleural, mediastinal, mesenteric, retroperitoneal, and pericalyceal fat.
Microthrombi with evidence of organization were observed in 10 of 19 calcified and stenotic aortic valves (53 percent). The organization that results from such thrombi may contribute to the deformity of the valve. Repetitive deposits of microthrombi, followed by organization and calcification, would explain the continuous process of stenosis in previously deformed aortic valves. The formation of such thrombi may be initiated by turbulent flow and other fluid dynamic factors.
We have observed abnormal echoes in the left ventricular outflow tract in 4 patients: 3 of the subjects had bacterial endocarditis and the fourth patient had myxomatous degeneration of the aortic valve (floppy aortic valve). A single diastolic echo with fine high frequency fluttering was seen in the patient with the floppy aortic valve, whereas the patients with endocarditis had associated infection of the mitral valve and an aneurysm of the anterior mitral leaflet, which was represented by dense systolic echoes on the proximal part of the mitral valve...