Masashi Uramatsu

Long-term prognosis of preoperative "bridge to surgery" expandable metallic stent insertion for obstructive colorectal cancer: comparison with emergency operation.

PURPOSE Expandable metallic stent endoprosthesis for preoperative “bridge to surgery” treatment of obstructive colorectal cancer has been broadly, clinically used with good short-term results. Stent insertion for malignant tumor, however, is controversial because of the increased risk of metastasis, invasion, and advancement of the cancer. We, first in the world, evaluated the long-term prognosis of expandable metallic stent insertion compared with emergency surgery without expandable metallic stent. METHODS Forty emergency operations (1986–1996) and 44 expandable metallic stent insertions (1993–2001) were retrospectively compared by history, duration, morbidity, and cumulative survival rate. RESULTS There was no significant difference in age or lesion between the two groups. Postoperative complications were significantly less frequent in the expandable metallic stent group: wound infection was 14 vs. 2 percent; leakage following to anastomosis was 11 vs. 3 percent. Long-term prognosis did not significantly differ: three-year overall survival rate was 50 vs. 48 percent; five-year survival rate was 44 vs. 40 percent in the emergency operation and expandable metallic stent groups, respectively. CONCLUSION Because preoperative expandable metallic stent insertion for obstructive colorectal cancer had good postoperative results and no disadvantages in long-term prognosis, this procedure should be used in preoperative treatments of obstructive colorectal cancer.

Omental cyst: report of a case.

Abstract We report the case of an omental cyst, a rare type of abdominal cystic lesion that is difficult to diagnose preoperatively. A 43-year-old man with no clinical symptoms was admitted to our hospital for investigation of an abdominal cyst detected by ultrasonography (US). We performed diagnostic examinations including US, computed tomography, and magnetic resonance imaging. An omental cyst was diagnosed because of its position and connection to the surrounding tissues. Pathological examination of the surgical specimen revealed endothelial cells on its internal wall and colonies of lymphocytes, confirming a diagnosis of lymphangioma, which is the most common type of omental cyst.

Involvement of endotoxin in the mortality of mice with gut-derived sepsis due to methicillin-resistant Staphylococcus aureus.

MRSA causes a wide diversity of diseases, ranging from benign skin infections to life‐threatening diseases, such as sepsis. However, there have been few reports of the pathophysiology and mechanisms of sepsis resulting from the gut‐derived origin of MRSA. Therefore, we established a murine model of gut‐derived sepsis with MRSA and factors of MRSA sepsis that cause deterioration. We separated mice into four groups according to antibiotic treatment as follows: (i) ABPC 40 mg/kg; (ii) CAZ 80 mg/kg; (iii) CAZ 80 mg/kg + endotoxin 10 μg/mouse; and (iv) saline‐treated control groups. Gut‐derived sepsis was induced by i.p. injection of cyclophosphamide after colonization of MRSA strain 334 in the intestine. After the induction of sepsis, significantly more CAZ‐treated mice survived compared with ABPC‐treated and control groups. MRSA were detected in the blood and liver among all groups. Endotoxin levels were significantly lower in the CAZ‐treated group compared to other groups. Inflammatory cytokine levels in the serum were lower in the CAZ‐treated group compared to other groups. Fecal culture showed a lower level of colonization of E. coli in the CAZ‐treated group compared to other groups. In conclusion, we found that CAZ‐treatment ameliorates infection and suppresses endotoxin level by the elimination of E. coli from the intestinal tract of mice. However, giving endotoxin in the CAZ‐treated group increased mortality to almost the same level as in the ABPC‐treated group. These results suggest endotoxin released from resident E. coli in the intestine is involved in clinical deterioration resulting from gut‐derived MRSA sepsis.

Interleukin-1 deficiency in combination with macrophage depletion increases susceptibility to Pseudomonas aeruginosa bacteremia

We evaluated the role of IL‐1 during Pseudomonas aeruginosa bacteremia by intravenously injecting P. aeruginosa strain D4 into IL‐1‐deficient and WT mice. The two strains showed equivalent mortality rates. However, when the mice were pretreated with cyclophosphamide, bacteremia‐induced mortality was significantly greater in the IL‐1‐deficient mice than in the WT mice (P < 0.01). We then investigated the role of neutrophils and macrophages in protecting IL‐1‐deficient mice from bacteremia by administering anti‐Gr‐1 antibody or liposomes containing dichloromethylene diphosphonate, respectively. After P. aeruginosa inoculation survival was significantly lower in the macrophage‐depleted IL‐1‐deficient mice than in the WT mice. In contrast, neutrophil depletion did not have this effect. Compared to the macrophage‐depleted WT mice, the macrophage‐depleted IL‐1‐deficient bacteremic mice had higher bacterial counts in various organs 48 and 72 hr post‐infection. They also had lower TNF‐α, IL‐6, and INF‐γ concentrations in their livers during the early phase of sepsis. Thus, IL‐1 deficiency becomes disadvantageous during P. aeruginosa bacteremia when it is accompanied by immunosuppression, particularly when macrophage functions are seriously impaired.

Twenty years of countermeasures against postoperative methicillin-resistant Staphylococcus aureus infections

PurposeA total of 7345 cases of digestive organ surgery were investigated over the course of 20 years.MethodsOwing to the increasing incidence of methicillin-resistant Staphylococcus aureus (MRSA) infections, we classified our countermeasures into periods A (September 1987 to February 1990), B (March 1990 to February 1997), C (March 1997 to February 1999), D (March 1999 to October 2004), and E (November 2004 to August 2007), and compared the number of infections during these periods. In period B, cefazolin and cefotiam were administered as prophylaxes. The treatment continued for 4 days, including the day of surgery. The patients undergoing endotracheal intubation or tracheotomy were managed with nonscreening pre-emptive isolation and cohorting (NSPEI&C), regardless of whether MRSA was present. However, NSPEI&C was halted in period C, but it was thereafter implemented again, and prophylactic antibiotics were administered only on the day of surgery during period D. In period E, prophylactic antibiotics were administered for 3 days.ResultsIn period A, MRSA was contracted in 4.1% (34/833) of patients. In period B, the MRSA isolation rate decreased to 0.3% (8/2722). In period C, the MRSA isolation rate increased to 3.4% (23/681). In period D, the MRSA isolation rate fell to 2.2% (40/1807). In period E, MRSA isolation cases significantly decreased to 0.4% (5/1302; P < 0.002 vs period D).ConclusionThe comprehensive management, selection of prophylactic antibiotics, and NSPEI&C were all considered to be effective.