Diagnostic Accuracy of a Noninvasive Test for Detection of Helicobacter pylori and Resistance to Clarithromycin in Stool by the Amplidiag H. pylori+ClariR Real-Time PCR Assay.

The noninvasive detection of Helicobacter pylori and its resistance to clarithromycin could revolutionize the management of H. pylori-infected patients by tailoring eradication treatment without any need for endoscopy when histology is not necessary. Several real-time PCR tests performed on stools have been proposed, but their performances were either poor or they were tested on too few patients to be properly evaluated. We conducted a prospective, multicenter study including 1,200 adult patients who were addressed for gastroduodenal endoscopy with gastric biopsies and who were naive for eradication treatment in order to evaluate the performance of the Amplidiag H. pylori+ClariR assay recently developed by Mobidiag (Espoo, Finland). The results of the Amplidiag H. pylori+ClariR assay performed on DNA from stools (automatic extraction with the EasyMag system [bioMérieux]) were compared with those of culture/Etest and quadruplex real-time PCRs performed on two gastric biopsy samples (from the antrum and corpus) to detect the H. pyloriglmM gene and mutations in the 23S rRNA genes conferring clarithromycin resistance. The sensitivity and specificity of the detection of H. pylori were 96.3% (95% confidence interval [CI], 92 to 98%) and 98.7% (95% CI, 97 to 99%), respectively. The positive and negative predictive values were evaluated to be 92.2% (95% CI, 92 to 98%) and 99.3% (95% CI, 98 to 99%), respectively. In this cohort, 160 patients (14.7%) were found to be infected (positive by culture and/or PCR). The sensitivity and specificity for detecting resistance to clarithromycin were 100% (95% CI, 88 to 100%) and 98.4% (95% CI, 94 to 99%), respectively.

Gestational choriocarcinoma associated with a germline TP53 mutation.

Choriocarcinoma is a highly malignant neoplasm resulting from the malignant transformation of proliferating trophoblastic cells and the molecular mechanisms leading to this transformation remain to be characterized. We report here the first case of a female germline TP53 mutation carrier who developed, as a first tumour, a lung choriocarcinoma, 6 months after a normal delivery. Molecular analyses established the gestational origin of the choriocarcinoma and showed, within the tumour, the presence of the germline mutant TP53 allele and loss of the wild-type allele. Resistance to methotrexate chemotherapy led to perform a surgical resection of the tumour. In agreement with the permissive role of TP53 mutations to oncogenic events, this report strongly suggests that TP53 mutations may promote malignant transformation of proliferating trophoblastic cells. Therefore, female TP53 mutation carriers may have an increased risk of developing gestational choriocarcinoma and might benefit from ß-hCG level monitoring after pregnancy.

Hemodynamic and antifibrotic effects of a selective liver nitric oxide donor V-PYRRO/NO in bile duct ligated rats.

AIM: To assess whether a liver specific nitric oxide (NO) donor (V-PYRRO/NO) would prevent the development of portal hypertension and liver fibrosis in rats with bile duct ligation (BDL). METHODS: Treatment (placebo or V-PYRRO/NO 0.53 micromol/kg per hour) was administered i.v. to rats 2 d before BDL (D-2) and maintained until the day of hemodynamic measurement (D26). Intra-hepatic NO level was estimated by measuring liver cGMP level. Effects of V-PYRRO/NO on liver fibrosis and lipid peroxidation were also assessed. RESULTS: Compared to placebo treatment, V-PYRRO/NO improved splanchnic hemodynamics in BDL rats: portal pressure was significantly reduced by 27% (P<0.0001) and collateral circulation development was almost completely blocked (splenorenal shunt blood flow by 74%, P=0.007). Moreover, V-PYRRO/NO significantly prevented liver fibrosis development in BDL rats (by 30% in hepatic hydroxyproline content and 31% in the area of fibrosis, P<0.0001 respectively), this effect being probably due to a decrease in lipid peroxidation by 44% in the hepatic malondialdehyde level (P=0.007). Interestingly, we observed a significant and expected increase in liver cGMP, without any systemic hemodynamic effects (mean arterial pressure, vascular systemic resistance and cardiac output) in both sham-operated and BDL rats treated with V-PYRRO/NO. This result is in accordance with studies on V-PYRRO/NO metabolism showing a specific release of NO in the liver. CONCLUSION: Continuous administrations of V-PYRRO/NO in BDL rats improved liver fibrosis and splanchnic hemodynamics without any noxious systemic hemo-dynamic effects.

New Doppler ultrasound signs improve the non-invasive diagnosis of cirrhosis or severe liver fibrosis.

OBJECTIVES: To determine whether ultrasound and, particularly, new Doppler signs increased the diagnostic accuracy of the most accurate, currently available markers for the diagnosis of cirrhosis or severe fibrosis. METHODS: Thirty-two clinical (n = 4), biochemical (n = 11) and Doppler ultrasound (n = 17) variables were recorded in 106 patients with compensated chronic liver disease. Diagnostic accuracy was evaluated by discriminant analysis; first, globally, using all variables then by stepwise analysis. RESULTS: (A) Diagnosis of cirrhosis. Using Doppler ultrasound, diagnostic accuracy was 92% (95% confidence interval 81-98) globally, and 89% (76-95) with three variables (spleen length, hepatic vein spectrum and maximum portal vein velocity). Based upon clinical signs, diagnostic accuracy was 86% (77-92) globally, and 85% (76-91) with one variable (firm liver). Based upon biochemical parameters, diagnostic accuracy was 80% (70-88) globally, and 81% (72-88) with two variables (hyaluronate and platelet count). Based upon all parameters, diagnostic accuracy was 91% (79-96.5) globally, and 91% (79-96.5) with four variables (firm liver, hyaluronate, platelet and hepatic vein spectrum). On an intention to diagnose basis, Doppler ultrasound provided a lower independent contribution due to missing data. (B) In the diagnosis of severe fibrosis, diagnostic accuracy was 83% (69-92) globally, and 77% (62-87) with one variable. CONCLUSIONS: Cirrhosis can be correctly diagnosed in approximately 90% of patients with compensated chronic liver disease using a few Doppler ultrasound signs including a new sign, the hepatic vein spectrum. Doppler ultrasound could be used for the first line diagnosis and biochemical markers, such as hyaluronate, in patients with missing Doppler ultrasound data.

Hemodynamic effects of acute and chronic administration of vapreotide in rats with cirrhosis.

The aim of this study was to assess the hemodynamic effects of acute and chronic administration of vapreotide, a somatostatin analog, in rats with intrahepatic portal hypertension induced by dimethylnitrosamine (DMNA) administration. Acute effects were evaluated at baseline and 30 min after placebo (N = 13) or vapreotide (8 /microg/kg/hr, N = 13) infusions in DMNA rats. Chronic hemodynamic effects were evaluated using subcutaneous implants for five weeks in anesthetized DMNA rats (placebo: N = 13, vapreotide: N = 13) and in sham rats (placebo: N = 10, vapreotide: N = 10). Hemodynamic measurements included splenorenal shunt blood flow (SRS BF) by the transit time ultrasound (TTU) method and cardiac output by the combined dilution-TTU method. Acute administration of vapreotide significantly decreased SRS BF (-17.3 +/- 19 vs - 1.1 +/- 14%, P < 0.05) and portal pressure (-8 +/- 9 vs 0 +/- 8%, p < 0.05) compared to placebo without systemic effects. Chronic administration of vapreotide significantly reduced the increase in SRS BF (2.4 +/- 1.5 vs 1.2 +/- 1.0 ml/min, P < 0.05) and cardiac index (50 +/- 15 vs 33 +/- 10 ml/min/100 g, P < 0.0001) while portal pressure and blood flow, and mean arterial pressure were not significantly changed compared to placebo. In conclusion, the acute administration of vapreotide decreased collateral circulation blood flow while chronic administration attenuated its development. Vapreotide seems to have a vasoconstrictive effect on collateral circulation.

Hemodynamic and antifibrotic effects of losartan in rats with liver fibrosis and/or portal hypertension.

BACKGROUND/AIMS: To assess the effects of the early and chronic administration of losartan--a specific angiotensin II receptor antagonist--in the prevention of hepatic fibrosis and portal hypertension. METHODS/RESULTS: (1) In CCl(4) rats, losartan at 5 and 10 mg/kg per day significantly decreased portal pressure (-11, -18%, respectively), splenorenal shunt blood flow (-60, -80%) and liver fibrosis (liver hydroxyproline and area of fibrosis) without significant changes in mortality and mean arterial pressure (MAP). (2) In bile duct ligated (BDL) rats, losartan at 5 mg/kg per day significantly decreased portal pressure (-14%), splenorenal shunt blood flow (-70%) and liver fibrosis. Losartan at 10 mg/kg per day significantly worsened liver and renal functions, mortality and liver fibrosis, without significant changes in portal pressure and splenorenal shunt blood flow. Losartan at 5 and 10 mg/kg per day significantly decreased MAP (-24, -30%). (3) In portal vein ligated (PVL) rats, losartan significantly decreased MAP (-12%) but did not change portal pressure or splenorenal shunt blood flow. CONCLUSIONS: In BDL and CCl(4) rats, losartan has beneficial effects on splanchnic hemodynamics and liver fibrosis. Losartan might decrease hepatic resistances in fibrotic liver. Losartan decreased MAP except in CCl(4) rats. Higher dosage of losartan had deleterious effects in BDL rats.

Prothrombin index is an indirect marker of severe liver fibrosis.

OBJECTIVE: The non-invasive diagnosis of liver fibrosis is based mainly on biochemical markers. The main aim was to validate whether the prothrombin index is an indirect marker of the severity of liver fibrosis. PATIENTS AND METHODS: The predictive value of the prothrombin index for liver fibrosis was first assessed in 243 patients with chronic liver disease, then validated in 193 other patients with chronic liver disease. The reproducibility of measurement of the prothrombin index in different laboratories was evaluated in 82 other patients. RESULTS: In the first group, the prothrombin index was predicted accurately by serum hyaluronate (R(2)= 0.67 at the first step by multiple regression). The relationship between the prothrombin index and the area of fibrosis was not influenced significantly by non-fibrotic pathological lesions. The prothrombin index began to decrease when the Metavir fibrosis score was 2 versus 3 for albumin. In the second group, the prothrombin index and the histological fibrosis score were well correlated (r= -0.70, P< 10(-4)). Prothrombin index < or =80% or < or =70% diagnosed severe fibrosis or cirrhosis, respectively, and prothrombin index > or =105% or > or =100% excluded a diagnosis of severe fibrosis or cirrhosis, respectively, at the 95% probability level. The prothrombin indices measured in different laboratories were similar (78+/-18% v. 78+/-14%) and well correlated (r= 0.91, P< 10(-4)). CONCLUSIONS: The prothrombin index was well correlated with pathological liver fibrosis score, had a high diagnostic accuracy for severe fibrosis or cirrhosis especially due to alcohol, and was not influenced by other pathological lesions. The prothrombin index was reproducible. Thus, the prothrombin index expressed as a percentage is an accurate, reproducible, inexpensive and easily available marker of severe liver fibrosis.

Fractal dimension can distinguish models and pharmacologic changes in liver fibrosis in rats.

Fractal analysis measures the complexity of geometric structures. The aim of this study was to evaluate the feasibility and accuracy of fractal analysis in liver fibrosis. A total of 77 rats were included: 10 sham, 46 with fibrosis secondary to bile duct ligation (BDL), and 21 with fibrosis due to CCl(4) intoxication. Measurements included the fractal dimension of Kolmogorov (D(k)), histologic lesions, the area of fibrosis by image analysis, liver hydroxyproline content, messenger RNA fibronectin, serum hyaluronate level, and portal pressure. Fibrotic rats were given placebo, octreotide, or O(2)-vinyl 1-(pyrrolidin-1-yl)diazen-1-ium-1,2-diolate (V-PYRRO/NO). Intraobserver agreement of D(k) was excellent with the intraclass (ic) correlation coefficient r(ic) = 0.91 (P <.0001) as well as the interobserver agreement with r(ic) = 0.88 (P <.001). D(k) was correlated with other measurements or markers of fibrosis: the area of fibrosis (r = 0.75; P <.0001), hydroxyproline content (r = 0.51; P <.001), serum hyaluronate level (r = 0.52; P <.001), and portal pressure (r = 0.52; P <.01). D(k) was significantly different between the 2 models of fibrosis (P <.0001), unlike the area of fibrosis, and this relationship was independent of other histologic lesions. The significant decrease in fibrosis observed with octreotide or V-PYRRO/NO was similarly reflected by D(k) or the area of fibrosis. The diagnostic accuracy for the fibrosis model was 97% with the 5 main measurements or markers of fibrosis studied, with D(k) isolated at the first step by stepwise analysis. In conclusion, fractal analysis is suitable for analyzing liver fibrosis and has excellent reproducibility. This is the only quantitative morphometric method that can discriminate among the models of fibrosis and is sensitive enough to detect pharmacologically induced changes in liver fibrosis.