Photodynamic therapy in normal pig stomach: protective effect of octreotide.

BACKGROUND AND STUDY AIMS: Many factors, such as oxygen and vasculature, are involved in the cytotoxic effect of photodynamic therapy (PDT). It is known that somatostatin and its analog octreotide decrease the splanchnic blood flow and have multiple inhibitory effects in different functions of the peptic system. The aim of this experimental study was to assess the effect of octreotide administration on PDT outcome in normal pig stomach. METHODS: 28 healthy pigs, randomly assigned to two groups, A and B, were studied. Pigs in both groups were sensitized with 0.3 mg/kg intravenous meta-tetra (hydroxyphenyl) chlorin (m-THPC), and 48 hours later light of wavelength 650 nm was delivered from a 50-mW diode laser for 300 s (energy fluence 15 J/cm (2)) through a gastroscope to the gastric mucosa. Group A underwent PDT without octreotide and group B had PDT with administration of octreotide. At 72 h after light delivery, all the animals were sacrificed for macroscopic and histological evaluation of the irradiated site. RESULTS: The macroscopic images and the histology of the stomach PDT lesions (inflammation, ulceration, necrosis) showed significantly less severity in the group of animals with octreotide injection (group B). In this group, full-thickness necrosis was observed in 28.5 %, compared with over 71.4 % in group A; this was statistically significant ( P < 0.05). CONCLUSION: Octreotide may have a modulating effect on m-TPHC PDT in normal gastric tissue in pigs, probably due to alterations of hemodynamics in the stomach and to suppression of the inflammatory process.

Clinical evaluation of an HIV-1 and HCV assay and demonstration of significant reduction of the HCV detection window before seroconversion.

BACKGROUND: One HIV-1 and HCV assay simultaneously detects HIV-1 and HCV RNA (Procleix, Chiron Corp.). The main intended use of the assay is the testing of blood and blood products in blood banking. STUDY DESIGN AND METHODS: To evaluate the clinical sensitivity of the assay, 164 anti-HIV-1+ and 160 anti-HCV+ patients of different viral load were tested. The assay specificity was determined in 1000 HIV-1- and HCV-seronegative blood donors. The ability of the assay to detect different HCV genotypes was investigated in a total of 40 patients of different genotypes (1-4). Furthermore, to investigate the reduction of the HCV window phase before seroconversion, serial samples of 25 hemodialysis patients who seroconverted to anti-HCV were also tested. RESULTS: The assay detected all 60 HIV-1-infected patients with a viral load of greater than 50 copies per mL and 48 of 104 patients with a viral load of less than 50 copies per mL. Moreover, all 60 patients with an HCV RNA load of greater than 521 IU per mL and 7 of 100 patients with a viral load of less than 50 IU per mL tested positive. The assay specificity was found to be 100 percent. In addition, all 40 patients of different HCV genotypes were successfully detected. Finally, the median time that the assay detected HCV infection before second- and third-generation anti-HCV assay was found to be 183 and 91 days, respectively. CONCLUSION: The assay sensitivity and specificity, its ability to detect different HCV genotypes, and the significant reduction of window period of HCV infection further support its use for improving the safety of blood and blood products.

Are metal stents effective for palliation of malignant dysphagia and fistulas?

BACKGROUND: One of the available treatments for unresectable oesophagogastric malignancies is the insertion of metal stents. AIMS: We evaluated prospectively 147 patients suffering from malignant dysphagia and/or fistula, after inserting a self-expandable metal stent. PATIENTS AND METHODS: The study included 147 patients (87 males, mean age 73 years). Dysphagia before and after stent placement was scored. Patients were divided in two groups according to dysphagia grade: group A (grade 0, 1) and group B (grades 2, 3, 4). Three types of stents were used: the Ultraflex stent (covered and uncovered) and the Flamingo one (covered). The total number of self-expandable metal stents placed was 183. A total of 92 of them were inserted following the combined endoscopic and fluoroscopic approach (42 by injecting lipiodol), while 91 were placed under endoscopic control only. Early and late complications were evaluated. RESULTS: Mean dysphagia score in group A, 1 day and 1 month after the procedure, was slightly reduced from 0.8 to 0.5/0.6 (p=NS), respectively. However, there was a statistically significant improvement (p<0.001) of mean dysphagia score in group B, from 2.4 initially to 1.1/1.4. Early complications occurred in 37 cases, late ones in 51. According to severity, minor complications occurred in 24 patients, major in 42, while life-threatening ones in 22. Survival ranged from 1 to 611 days and 1-week mortality was 9%. Stent-related death occurred in six patients. CONCLUSIONS: All kinds of endoscopic methods used for stenting in the present study were easy to perform even on an out-patient basis. Insertion of self-expandable metal stents is effective in patients with dysphagia scores > or = 2. It might not clinically improve patients with dysphagia score <2, so selection of patients for stenting is essential to avoid unnecessary procedures. Moreover, their high cost, high complication rates and low overall survival may improve following better selection criteria.

B2 microglobulin: is it a reliable marker of activity in inflammatory bowel disease?

OBJECTIVES: The aims of this study were to investigate a possible positive correlation between B2-microglobulin (B2-M) serum levels and the severity and activity of inflammatory bowel disease (IBD); and to examine whether B2-M levels reflect IBD extent. METHODS: We examined B2-M serum levels in 87 ulcerative colitis (UC) patients, 74 with Crohn's disease (CD) and 68 control subjects, using an enzymatic method. The reliability of the measuring method was assessed by evaluating serum B2-M in 18 patients suffering from chronic renal failure (CRF). The severity and activity of IBD was estimated using the van Hees Activity Index and the True-love-Witts criteria for CD and UC patients respectively. Endoscopic evaluation for UC patients was done according to Baron's et al. classification; Riley's et al. criteria were used for histological evaluation. RESULTS: B2-M serum levels were significantly increased in all CD patients except those in remission. After 6 months treatment a second blood sample taken from CD patients with initially elevated B2-M levels proved to be compatible with CD severity at that time. Such a positive correlation was not assessed in UC patients; therefore, a second blood sample was considered unnecessary. Furthermore, CD patients with pancolitis, ileal-caecal, or small intestinal disease had higher B2-M levels than those with left-sided, anal, or perianal disease. CONCLUSIONS: B2-M serum levels could prove to be a useful marker in assessing not only the activity, severity, and extent of CD but the treatment efficacy as well.

Colonic tuberculosis and adenocarcinoma: an unusual presentation.

A case is presented of caecal tuberculosis coexisting with adenocarcinoma at the same site, unusually presenting as a right iliac fossa abscess. The relevant literature on 61 previously reported patients with coexisting tuberculosis and colonic carcinoma is reviewed. The patient was 81-years-old, female with a tender swelling in the right iliac fossa. Following examination by ultrasound, laparotomy was undertaken which revealed a large abscess cavity contaminated by Mycobacterium tuberculosis. Although anti-tuberculosis treatment was given, there was a persistent purulent discharge from the wound, so a new ultrasound, computed tomography scan and barium enema were arranged. These could not clearly differentiate between ileocaecal tuberculosis and carcinoma. A second laparotomy showed that there was an underlying adenocarcinoma. Although rare, the coexistence of colonic tuberculosis with carcinoma should be seriously considered especially in patients who fail to respond to anti-tuberculosis treatment. A definitive diagnosis can be established only by histological examination.