[Adult multiple coronary aneurysms of Kawasaki's disease's sequelae; two autopsy cases].

Coronary aneurysm in Kawasaki's disease (Acute febril infantile mucocutaneous lymph node syndrome, MCLS) may cause sudden death in childhood and ischemic heart disease in adults. We encountered two adult autopsy cases of Kawasaki's disease with multiple coronary aneurysms. The first case was a 56-year-old man who hospitalized due to recurrent syncope since 51 years of age. At age 55 coronary angiography (CAG) had shown multiple aneurysms in the left and right coronary artery. In September 1991, he developed chest pain and was brought to the hospital, almost dead on arrival (DOA). The patient died later the same day despite cardiopulmonary resuscitation. Autopsy findings showed cardiomegaly (470 g) with multiple coronary aneurysms of three coronary arteries. Microscopically, intimal thickening and medial thinning were found in the aneurysmal wall with calcification and disruption of the internal elastic lamina. The second case, a 28-year-old man had been diagnosed with rheumatic fever and mitral regurgitation at 4 years of age. Coronary aneurysms were noted on CAG at 26 years of age. In April 1992, he developed fever and was admitted to a local hospital where he was diagnosed with infectious endocarditis. After his being transferred to our hospital, disturbance of consciousness suddenly developed and he died in September 1992. Autopsy findings showed cardiomegaly (430 g) with left ventricular hypertrophy and multiple coronary aneurysms in left anterior descending coronary artery and left circumflex coronary artery. The aneurysmal wall showed intimal thickening and medial thinning with multiple recanalizations of occlusive lumina and fibrous intimal thickening. The mitral valve showed mild fibrosis and calcification without valvular deformity. There was no evidence of bacterial endocarditis. Both cases were finally diagnosed as Kawasaki's disease. Ischemic heart disease or lesions related to coronary aneurysm in Kawasaki's disease may show an increased incidence in the near future. Kawasaki's disease should have been followed even in adulthood after treatment in childhood.

[Regression of atherosclerosis and centrally depressed lesions in rabbit aortas].

Atherosclerotic plaque with central depression (depressed lesion) has been hypothesized to be a morphological feature of atherosclerosis regression. We tested this hypothesis in New Zealand white rabbits. After the animals were fed a diet containing 1% cholesterol for three months, they were changed to a normal diet for 6 to 9 months. Several aortas had centrally depressed lesions similar to those found in elderly people, and the animals had low serum cholesterol levels. Immunohistochemical study showed that the depressed lesions contained more smooth muscle cells and collagen type IV, and fewer macrophage-derived foam cells than did common atherosclerotic elevated lesions found in rabbits. We know of no other report of depressed lesions in rabbits with atherosclerosis. Thus we believe that the centrally depressed lesion is a histological characteristic of regression of atherosclerosis.

[Atherosclerosis regression in the elderly--correlation between centrally depressed lesions and risk factors].

Atherosclerotic plaque with central depression (depressed lesion) may indicate regression of atherosclerosis in the aorta. Aortic depressed lesions have a solitary elevated area of plaque with a sharply-bordered roung depression in its center and no area ulceration. This may be interpretable as a sign of regression of atherosclerosis. To clarify the pathogenesis of depressed lesion, we studied clinical risk factors such as hypercholesterolemia in patients with depressed lesions that were confirmed at autopsy. The patients were divided into 3 groups according to their total cholesterol level at autopsy: a high-risk group (> or = 220 mg/dl), a moderate-risk group (180-220 mg/dl), and a low-risk group (< or = 180 mg/dl). Depressed lesions were found in 16.4% of those in the high-risk group, in 14.6% of those in the moderate-risk group and in 69.0% of those in the low-risk group. Severe aortic atherosclerosis was found in 69.8% of the patients; 50.9% of those with severe disease were in the-low risk group. Depressed lesions were also found in those with low levels of low-density lipoprotein cholesterol (< or = 140 mg/dl), 58.8% of whom were found to have severe atherosclerosis. There was no relationship between total cholesterol level and the presence of depressed lesions. However, a clinical prevention trial may result in sufficient control of ahterosclerosis among those in the high-risk group and may also lead to regression of aortic lesions.

[Quality assurance of pathology laboratories: analysis of histopathological diagnosis of endoscopical biopsies from lower alimentary tract based on specimen types].

As a part of the internal quality assurance in the pathology laboratories, we focused on the diagnosis of biopsies from the lower alimentary tract, and investigated the number of independent lesions contributing the specimens, biopsy pieces, and paraffin blocks prepared in each pathological examination, from the standpoint of the types of biopsy procedures employed. In addition, we compared those of pre- and post-operative diagnoses, and examined the adequacy in the cases with repeated biopsies. Regarding the procedures, polypectomy and EMR (endoscopical mucosal resection) accounted for more than 60% of all the specimens handled during the study period. Most of the specimens taken by polypectomy or EMR were derived from neoplastic conditions, and roughly 40% of them were from malignancies including borderline lesions in a narrow sense. The examination of the surgically resected specimens confirmed a hundred percent accuracy ratio of the diagnosis on the biopsy specimens. Three cases (7.1%) out of 42 malignancies resected needed repeated biopsies in preoperative confirmation of malignancy, while the remainder (92.9%) had been diagnosed at the initial biopsy. The result disclosed that biopsies possessing both diagnostic and therapeutic value (polypectomy and EMR) are apparently increased in the field of lower alimentary tract, and the difficulty and efforts required for diagnosis are quite different and depend on the biopsy procedures employed.