Acquired toxoplasmic lymphadenitis with demonstration of the cyst form.

Acquired toxoplasmosis usually is diagnosed serologically. Specific histologic criteria allow for the recognition of this disease in lymph node sections. However, Toxoplasma cysts are rarely seen in nodes. The lymph node from a 15-year-old male with asymptomatic lymphadenopathy was found to have typical histologic features of toxoplasmic lymphadenitis. Toxoplasma cysts were identified and specific serology was confirmatory.

Pathology of active infective endocarditis: a necropsy analysis of 192 patients.

Successful treatment of infective endocarditis often requires cardiac valve replacement during the active infection. This is especially the case with aortic valve infection, and with infection of valve prostheses in either the aortic or mitral position. Valve excision with or without replacement, however, is also sometimes required for tricuspid valve infection (1). This discussion will focus on the morphologic aspects of active infective endocarditis involving both right and left-sided native cardiac valves. It will also examine certain morphologic aspects of mechanical and bioprosthetic valve substitutes. The information is derived from necropsy examination by the authors of 192 patients with active infective valvular endocarditis (Table 1). Of the 192 patients, 129 were described in an earlier publication (2). Patients with infective endocarditis complicating congenital heart disease with a shunt (6 patients), and those with infective endocarditis following valvulotomy (4 patients) are omitted from this analysis.

Coronary artery narrowing in coronary heart disease: comparison of cineangiographic and necropsy findings.

Of 10 patients with fatal coronary heart disease undergoing coronary angiography 0 to 69 d (average, 21) before necropsy, the amount of narrowing in 61 coronary arteries observed angiographically (diameter reduction) during life by three angiographers was compared with that observed histologically (cross-sectional area) at necropsy. No overestimations of the degree of narrowing were made angiographically. Of 11 coronary arteries or their subdivisions narrowed 0 to 50% in cross-sectional area histologically, none were underestimated angiographically; of eight narrowed 51% to 75% histologically, seven had been underestimated, and of 42 narrowed 76% to 100% histologically, 17 were underestimated angiographically. The coronary atherosclerotic plaquing was diffuse (greater than 25% cross-sectional area narrowing) in 90% of 467 five-millimetre segments of coronary artery examined (24 cm per patient), and this diffuseness of the atherosclerotic process seems to be the major reason for angiographic underestimation of coronary narrowings.

Cerebrovascular occlusion in a transsexual man taking mestranol.

The Collaborative Study Group for the Study of Stroke in Young Women studied 598 women from age 15 to 44 years with cerebrovascular disease. They found that the use of oral contraceptives was significantly more prevalent in women who had suffered a thrombotic stroke than in women who had not had strokes. The risk of thrombotic stroke was estimated to be nine times greater in users of oral contraceptives than in nonusers. We report a case in which a previously healthy man who was using an oral contraceptive drug developed middle cerebral artery occlusion. In the absence of other predisposing factors in this case, it appears that the cerebrovascular occlusion was related to estrogen administration. The occurrence of persistent severe headaches in patients using estrogenic hormones may be a clue to impending cerebrovascular occlusion.

Prosthetic-valve endocarditis due to Listeria monocytogenes.

Clinical and necropsy observations in the case of a patient with prosthetic-valve endocarditis due to Listeria monocytogenes are presented. Although rare cases of L. monocytogenes infection of natural cardiac valves have been reported, this represents the first known case of infection of a prosthetic cardiac valve by this organism.

Fibrosing mediastinitis causing pulmonary arterial hypertension without pulmonary venous hypertension. Clinical and necropsy observations.

Clinical and morphologic observations are described in two patients with severe pulmonary arterial hypertension without pulmonary venous hypertension from fibrosing mediastinitis. In one patient, both main pulmonary arteries and one major pulmonary vein were severely narrowed by dense fibrous tissue; in the second patient, only the right main pulmonary artery was severely narrowed. Both patients had normal intrapulmonary arteries and normal pulmonary parenchyma. Of nine previously described necropsy patients with pulmonary hypertension due to fibrosing mediastinitis, seven had severe narrowing of multiple large pulmonary veins and in six of them the pulmonary hypertension was entirely due to pulmonary venous obstruction. In one other patient, the pulmonary hypertension was due to obstruction of one main pulmonary artery and several large pulmonary veins. Each of these seven previously described patients had severe changes in the small intrapulmonary arteries. Of the other two previously described patients with pulmonary hypertension from fibrosing mediastinitis, one had severe narrowing of only the main right pulmonary artery, and the other, of both main pulmonary arteries. Thus, although pulmonary arterial hypertension in patients with fibrosing mediastinitis is usually due to obstruction of multiple large pulmonary veins and to severe secondary changes in small intrapulmonary arteries, fibrosing mediastinitis can cause severe pulmonary hypertension by obstructing the right or both main pulmonary arteries.

Prosthetic valve endocarditis: clinicopathologic analysis of 22 necropsy patients with comparison observations in 74 necropsy patients with active infective endocarditis involving natural left-sided cardiac valves.

Clinical and morphologic features are described in 22 necropsy patients with endocarditis involving rigid-framed prosthetic valves: aortic in 15 patients and mitral in 7. The interval from valve replacement to onset of symptoms of prosthetic valve endocarditis was less than 2 months in 8 patients and longer than 2 months in 14 patients. The most frequent infecting organism was the Staphylococcus (13 patients). In each of the 22 patients the infection was located behind the site of attachment of the prosthesis to the valve ring, and the infection spread to adjacent structures in 13 patients, 11 of whom had aortic prostheses. Prosthetic detachment causing severe regurgitation occurred in 12 of the 15 patients with an infected aortic valve prosthesis, and in 2 of the 7 with an infected mitral valve prosthesis. Prosthetic obstruction by vegetative material occurred in 5 of 7 patients with prosthetic mitral infection and in only 1 of 15 with prosthetic aortic infection. High degrees of conduction defects developed in seven patients with aortic prosthetic valve endocarditis: complete heart block in five, and complete left bundle branch block in two. Comparison of observations in the 22 patients with prosthetic valve endocarditis with those in 74 patients with active infective endocarditis involving natural left-sided cardiac valves revealed significant (P less than 0.05) differences in the percent with ring abscess, hemodynamic consequences of the endocarditis (valve stenosis), frequency of Staphylococcus as the causative organism and percent with complete heart block or left bundle branch block. No significant differences were observed between the two groups when comparing age, sex, type of underlying valve disease or frequency of organ infarcts of splenomegaly.

Valve ring abscess in active infective endocarditis. Frequency, location, and clues to clinical diagnosis from the study of 95 necropsy patients.

Analysis of 95 necropsy patients with active infective endocarditis (AIE) involving 128 native cardiac valves (aortic = 59, mitral = 48, tricuspid = 20, and pulmomic = 1) disclosed 27 patients with ring abscesses involving 30 valves: the aortic valve ring was infected in 24 patients and only an atrioventricular valve ring (mitral in two, and tricuspid in one) in three patients. Comparison of the following parameters showed no significant differences between the 27 patients with and the 68 patients without ring abscess: age, sex, antibiotic treatment or length of treatment, status of the cardiac valve(s) before infection, and the kind of infecting organism. Comparison of the following parameters, however, showed significant (P less than 0.05) differences between the 27 patients with and the 68 patients without valve ring abscess: 1) infection of the aortic valve; 2) occurrence of valvular regurgitation of recent origin; 3) presence of pericarditis; 4) presence of high degree of atrioventricular block; and 5) short duration of symptoms leading to severe debility or death. These five features, therefore, serve as a clinical clues to the presence of valve ring abscess in patients with AIE.

Intravenous injection of talc-containing drugs intended for oral use. A cause of pulmonary granulomatosis and pulmonary hypertension.

Clinical and morphologic features are described in two patients known to have repeatedly injected intravenously talc-containing drugs intended for oral use. In one patient severe pulmonary hypertension developed; the talc granulomas in him were located predominantly within the pulmonary arteries. The second patient had normal pulmonary arterial pressures, and the talc granulomas in him were located predominantly in the pulmonary interstitium. Of 19 previously described patients with pulmonary talc granulomas, 12 had morphologic evidence of pulmonary hypertension (in three of severe degree); in each, talc granulomas were located predominantly within the pulmonary arteries. In those without signs of pulmonary hypertension, granulomas were located predominantly in the pulmonary interstitium. Why there are differences in the distribution of the talc granulomas is unclear. It is clear, however, as demonstrated by one of our patients, that severe pulmonary hypertension may be a consequence of intravenous injection of drugs intended for oral use.