Tadataka Hayashi

Real-time analysis of platelet aggregation and procoagulant activity during thrombus formation in vivo

The exact mechanism of blood vessel thrombus formation remains to be defined. Here, we introduce a new approach to probe thrombus formation in blood vessels of living animals using intravital microscopy in green fluorescent protein (GFP)-transgenic mice to simultaneously monitor platelet aggregation and procoagulant activity. To this end, GFP-expressing platelets and annexin A5 labeled with a fluorescent dye were employed to visualize and analyze platelet aggregation and markers of procoagulant activity (platelet surface phosphatidylserine (PS)). Laser-induced thrombi increased and then decreased in size with time in vessels of living animals, whereas platelet surface PS initiated at the site of injury and then penetrated into the thrombus. PS-positive platelets were predominantly localized in the center of the thrombus, as was fibrin generation. The experimental system proposed here is a valuable tool not only for investigating mechanisms of thrombus formation but also to assess the efficacy of antithrombotic drugs within the vasculature.

Refractory Ulcerative Colitis Complicated by a Cytomegaloviral Infection Requiring Surgery: Report of a Case

Cytomegalovirus (CMV) infection has been reported to be a cause of refractory ulcerative colitis (UC). We herein report a case of refractory ulcerative colitis complicated by CMV infection requiring surgery. A 22-year-old man was admitted to our hospital with lower abdominal pain and bloody diarrhea. Under a diagnosis of acute UC, he was treated with prednisone 60 mg/day and sulfasalazine. Since his symptoms appeared to improve, the prednisone dosage was gradually reduced to 20 mg/day. After 5 months, he had an unexpected flare-up with fever and fresh anal bleeding. Colonoscopy demonstrated a punched out ulcer in the sigmoid colon. Biopsies by colonoscopy revealed cytomegalic inclusion bodies. Serologic and immunologic studies also suggested a recent CMV infection. Under a diagnosis of intractable UC complicated by a CMV infection, ganciclovir therapy was carried out, and the steroid therapy was tapered. Although the serum antigenemia became negative after the antiviral therapy, follow-up colonoscopy confirmed the severe stenosis after the punched-out ulcer healed completely. Since his symptoms did not improve, it was necessary to perform an elective proctocolectomy despite antiviral therapy. He was discharged with an uneventful postoperative course. It is important to recognize CMV colitis as a complication of inflammatory bowel disease, particularly in severe steroid-resistant colitis. Furthermore, in cases which fail to respond to antiviral treatment, the patient may ultimately require surgery.

Ulcerative Colitis Accompanied with Sarcoidosis and Dermatomyositis : Report of a Case

We report a rare case of ulcerative colitis with sarcoidosis and dermatomyositis. A 33-year old woman had a ten-year history of ulcerative colitis and dermatomyositis. After nine-year maintenance treatment with sulphasalazine and steroids, she underwent a proctocolectomy and ileal pouch-anal anastomosis because of deterioration of ulcerative colitis. One year after the operation, she noticed some subcutaneous masses in the right forearm and left lower leg. A total biopsy of the mass was performed, and noncaseous epithelioid granulomas were found in the specimen. Chest roentgenogram and chest computed tomography showed hilar adenopathy and a diffuse granular shadow. The diagnosis of sarcoidosis was made. Concomitant development of ulcerative colitis and sarcoidosis may not be incidental, and there may be a common factor in the two diseases. Ulcerative colitis also may be a part of a systemic disorder associated with abnormal immune reactions. Complications by disorders associated with other immunologic abnormalities, as noted in this patient, should be kept in mind in the management of ulcerative colitis.

Crohn’s disease-associated colorectal cancer in Japan: report of four cases

PurposeWe report four cases of Crohn’s disease (CD)-associated colorectal cancer (CRC) in our department.Case 1A 42-year-old Japanese man had a 14-year history of ileocolon CD. He had a history of an ileocecal resection and a stricture plasty. At the age of 42, sigmoid colostomy was performed because of the deterioration of the anal stenosis. After this operation, the perianal pain had remained, and a magnetic resonance imaging scan revealed a rectal tumor.Case 2A 30-year-old Japanese man had a 13-year history of ileocolon CD. He had a history of an ileostomy, a subtotal colectomy, and ileo-rectal anastomosis. At the age of 30, he had perianal pain, and a colonoscopy revealed a rectal cancer. An abdomino-perineal resection of the remnant rectum was performed.Case 3A 46-year-old Japanese man had a 9-year history of ileocolon CD. He experienced abdominal fullness. Colonoscopy revealed an ascending colon cancer. He underwent a subtotal colectomy and ileo-rectal anastomosis.Case 4A 33-year-old Japanese woman had a 16-year history of ileocolon CD. She had no changes in symptoms of CD. Surveillance colonoscopy revealed a transverse colon cancer. She underwent a subtotal colectomy and ileo-rectal anastomosis.ConclusionAs the number of patients with CD and with CD-associated CRC has increased in Japan, CD-associated CRC, as noted in these patients, should be kept in mind in the management of patients with CD. In addition, a surveillance system of patients with CD should be established and should prompt further study about CD-associated CRC.

Granulocytic sarcoma presenting as a thrombosed external hemorrhoid in a patient with myelodysplastic syndrome overt leukemia

A 67-year-old Japanese man complained of a painful lump in his anus. He had a 15-month history of myelodysplastic syndrome (MDS) and had been diagnosed with MDS overt leukemia. A solid lump measuring 1.0 cm in diameter was detected in the anal verge. Under a diagnosis of a thrombosed external hemorrhoid, thrombectomy was performed under local anesthesia. One week after thrombectomy, the wound had not healed, and grayish-green tissue was seen at the bottom. A biopsy of the wound revealed atypical mononuclear cell infiltration. Myeloperoxidase and lysozyme were positive on immunohistochemical staining. Finally, the diagnosis of granulocytic sarcoma (GS) was made. Though it is well known that perianal complications occur quite often in patients with leukemia, it is unusual for a diagnosis of GS of the anus to be definitely established. To our knowledge, there has not been a previous report of GS presenting as a thrombosed external hemorrhoid. The development of GS should be considered during the management of such lesions, especially in patients with bone marrow disorders, such as acute myeloid leukemia (AML) or high-risk MDS.