Hiroshi Yasuhara

Acute Mesenteric Ischemia : The Challenge of Gastroenterology

Intestinal ischemia has been classified into three major categories based on its clinical features, namely, acute mesenteric ischemia (AMI), chronic mesenteric ischemia (intestinal angina), and colonic ischemia (ischemic colitis). Acute mesenteric ischemia is not an isolated clinical entity, but a complex of diseases, including acute mesenteric arterial embolus and thrombus, mesenteric venous thrombus, and nonocclusive mesenteric ischemia (NOMI). These diseases have common clinical features caused by impaired blood perfusion to the intestine, bacterial translocation, and systemic inflammatory response syndrome. Reperfusion injury, which exacerbates the ischemic damage of the intestinal microcirculation, is another important feature of AMI. There is substantial evidence that the mortality associated with AMI varies according to its cause. Nonocclusive mesenteric ischemia is the most lethal form of AMI because of the poor understanding of its pathophysiology and its mild and nonspecific symptoms, which often delay its diagnosis. Mesenteric venous thrombosis is much less lethal than acute thromboembolism of the superior mesenteric artery and NOMI. We present an overview of the current understanding of AMI based on reported evidence. Although AMI is still lethal and in-hospital mortality rates have remained high over the last few decades, accumulated knowledge on this condition is expected to improve its prognosis.

Factors Affecting the Early Mortality of Patients with Nontraumatic Colorectal Perforation

Abstract.Purpose: We attempted to identify the factors associated with the early mortality of patients with nontraumatic colorectal perforation.nMethods: Eighty patients who underwent surgery for nontraumatic colorectal perforation between May 1986 and December 1999 were retrospectively reviewed. Age, sex, cause of perforation, duration of symptoms, associated preoperative septic shock, concomitant disorders (including cardiac disease, chronic obstructive pulmonary disease, hemodialysis, and steroid treatment), operative findings (such as the site of perforation and the degree of peritonitis), and results of preoperative laboratory blood tests (such as the white blood cell count and platelet count) were analyzed for their association with early outcome using univariate and multivariate analyses.nResults: Fourteen of the 80 patients died during hospitalization. According to the univariate analysis, advanced age, preoperative septic shock, concomitant disabling cardiac disease, hemodialysis, diffuse peritonitis, and a low preoperative platelet count were more frequent in the patients who died during hospitalization. According to the logistic regression analysis, preoperative septic shock (odds ratio 8.443, 95% confidence interval (CI) 1.625–43.873), concomitant end-stage renal failure (odds ratio 13.641, 95% CI 1.643–113.244), and diffuse peritonitis (odds ratio 13.212, 95% CI 1.441–121.102) were the most significant factors related to in-hospital mortality.nConclusion: Early diagnosis before the patients general condition deteriorates is a key to improving the early mortality associated with nontraumatic colorectal perforation, especially in patients with concomitant end-stage renal failure.

Influence of diabetes on persistent nonhealing ischemic foot ulcer in end-stage renal disease

The aim of this study was to identify important atherosclerotic risk factors for characteristic nonhealing ischemic foot ulcers in patients with end-stage renal failure. We retrospectively studied 534 consecutive hemodialysis patients in five dialysis units of the Tokyo metropolitan area between 1980 and 1999. The influence of risk factors for ischemic foot ulcers in hemodialysis patients was determined using a multivariate logistic model. The characteristic features were also evaluated with further comparison of the prevalence of risk factors between hemodialyzed diabetic patients with ischemic foot ulcers and another 61 age- and gender-matched nonhemodialyzed diabetic patients with ischemic foot ulcers. In the logistic model, two factors emerged as important risk factors for ischemic foot ulcers: renal failure due to diabetes [odds ratio 21.580 (95% CI 4.838–96.251); p=0.0001] and a history of cerebrovascular disease [odds ratio 2.782 (1.015–7.624); p=0.0467]. On the basis of a comparison of age- and gender-matched control patients, associated diabetic triopathy, a history of cerebrovascular disease, and hypertension were more frequent in the hemodialysis patients. The development of ischemic foot ulcers in those with end-stage renal failure is strongly influenced by underlying advanced diabetic microangiopathy and such other factors as sequelae of cerebrovascular disease and patient debilitation.RésuméLe but de cette étude a été de déterminer les facteurs de risque de l’athérosclérose et leur rôle dans la cicatrisation d’ulcères ischémiques chroniques du pied, lésion caractéristique de l’insuffisance rénale terminale. Nous avons étudié de façon rétrospective 534 patients consécutifs en hémodialyse dans cinq unités de dialyse dans la région métropolitaine de Tokyo entre 1980 et 1999. Les facteurs favorisants de l’ulcère ischémique du pied chez le patient en hémodialyse ont été déterminés par un modèle de régression logistique. Les facteurs caractéristiques ont également été évalués par une comparaison ultérieure de la prévalence des facteurs de risque entre les patients diabétiques porteurs d’ulcère ischémique du pied et 61 autres patients diabétiques non hemodialyses, appariés pour l’âge et le sexe. Selon le modèle logistique, deux facteurs ont émergé comme facteurs de risque importants pour l’ulcère ischémique du pied: l’insuffisance rénale en rapport avec le diabète [rapport de côte: 21.580 (95% IC: 4.838–96.251), p=0.0001] et histoire de maladie cérébrovasculaire [rapport de côte=2.782 (1.015–7.624), p=0.0467]. Basé sur la comparaison des patients appariés pour l’âge et le sexe, la triopathie diabétique associée, une histoire de maladie cérébrovasculaire et une hypertension sont plus fréquemment constatées chez lez patients hemodialyses. Le développement d’ulcère ischémique du pied dans l’insuffisance rénale terminale est fortement influencé par la microangiopathic diabétique avancée et d’autres facteurs tels les séquelles de maladie cérébrovasculaire et la debilitation du patient.ResumenEl trabajo trata de averiguar la importancia de los factores de riesgo arterioescleróticos en la génesis del mal perforante plantar, en pacientes en estadio terminal por fracaso renal. Se efectúa un estudio retrospectivo que comprende 534 pacientes hemodializados, en 5 unidades de hemodiálisis ubicadas en el área metropolitana de Tokio, entre 1980 y 1999. Utilizando un modelo logÍstico multivariante se determinó, en pacientes hemodializados, los factores de riesgo en la génesis de la úlcera isquémica del pie. Se compararon además, los factores de prevalencia entre el mal perforante plantar de los diabéticos hemodializados, con 61 pacientes diabéticos, homologables por lo que al sexo y edad se refiere, con mal perforante plantar pero que no precisaron hemodiálisis. El modelo logÍstico demostró, la existencia de dos factores de riesgo importantes, por lo que al mal perforante plantar atañe: el fracaso renal diabético [odds ratio=21.580 (95% CI 4.838-96.251), p=0.0001] y los antecedentes de enfermedad cerebro-vascular [odds ratio=2.782 (1.015–7.624), p=0.0467]. Comparando con pacientes control, homologables por lo que a la edad y sexo se refiere, constatamos que en los pacientes hemodializados es más frecuente la asociación de diabetes, enfermedad cerebro-vascular e hipertensión. El desarrollo del mal perforante plantar en el estadio final de pacientes con fracaso renal, viene propiciado por la grave microangiopatÍa diabética, asÍ como por otros factores tales como: secuelas de la enfermedad cerebro-vascular y el mal estado general del paciente.

Tuberculous Peritonitis Defying Diagnosis : Report of a Case

A case of tuberculous peritonitis, which has beenscarcely encountered in clinical practice in recent years, is reported. A 32-year-old man was admitted to our hospital complaining of abdominal fullness, anorexia, and a 15kg weight loss. His abdomen was distended. There was neither any previous history nor recent contact with tuberculosis. The laboratory data indicated increased C-reactive protein and erythrocyte sedimentation rate, but the white blood cell count was normal. A chest X-ray examination revealed no abnormalities. abdominal X-ray showed scattered, small-intestinal gas shadows. Abdominal computed tomography scanning revealed a diffuse thickening of the dilated bowel wall, mainly adjacent to the mesentery. After a detailed examination a diagnosis of peritonitis carcinomatosa of unknown origin was suspected, and an exploratory laparotomy was done. Severe adhesions between the parietal peritoneum and the bowel were found. An excisional biopsy specimen was taken from the peritoneum, and a diagnosis of tuberculosis was thus made. Triple therapy with isoniazid, rifampicin, and kanamycin was started, and both the intestinal obstruction and anorexia were thus resolved.

Influence of gender on intraluminal thrombus of abdominal aortic aneurysms

BACKGROUNDnThe mechanisms of formation of intraluminal thrombus (ILT) of abdominal aortic aneurysms (AAA) remain unknown. The aim of this study was to investigate the pathogenesis of AAA by analysis of ILT.nnnMETHODSnWe retrospectively analyzed the size of ILT in 98 consecutive patients with AAA undergoing abdominal computed tomography (CT) examination. The volume of ILT was estimated by the area ratio of ILT in CT images. Important baseline variables related to small ILT were determined using logistic-regression analysis.nnnRESULTSnThere were two apparent peaks in the distribution of ILT ratio. Thirteen of 98 patients had negligible ILT with ratio < or = 0.1. Female gender was the only patient characteristic independently significantly correlated with small ILT (odds ratio 5.214, P = 0.0096).nnnCONCLUSIONnOur findings provide important evidence that AAA is formed by at least two different pathogenic processes. It is likely that this difference in mechanisms may be caused partly by sex hormones.

Gastric carcinoma presenting with extensive extraluminal growth: Report of a case

We report a 48-year-old-man with gastric carcinoma presenting with an unusual extraluminal growth. The patient underwent a barium meal examination and gastrofiberscopy because of progressive anemia over 6 months. These examinations revealed a Borrmann type 3 advanced gastric carcinoma of the greater curvature of the antrum. Biopsies showed moderately differentiated tubular adenocarcinoma. The intraoperative findings showed gastric carcinoma associated with extensive extraluminal invasion into the adjacent organs, i.e., the transverse colon and mesocolon. A palliative distal gastrectomy with a partial resection of the transverse colon was performed because of peritoneal dissemination found in the mesocolon and rectovesical pouch. A histological examination of the specimen confirmed adenocarcinoma which had massively infiltrated the transverse colon and mesocolon. His postoperative course was uneventful. However, he died of peritonitis carcinomatosa 9 months later.