Detection of non-alcoholic steatohepatitis in patients with morbid obesity before bariatric surgery: preliminary evaluation with acoustic radiation force impulse imaging.

OBJECTIVE: To investigate the utility of acoustic radiation force impulse (ARFI) imaging, with the determination of shear wave velocity (SWV), to differentiate non-alcoholic fatty liver disease (NAFLD) from non-alcoholic steatohepatitis (NASH) in patients with morbid obesity before bariatric surgery. METHODS: Thirty-two patients with morbid obesity were evaluated with ARFI and conventional ultrasound before bariatric surgery. The ARFI and ultrasound results were compared with liver biopsy findings, which is the reference standard. The patients were classed according to their histological findings into three groups: group A, simple steatosis; group B, inflammation; and group C, fibrosis. RESULTS: The median SWV was 1.57 ± 0.79 m/s. Hepatic alterations were observed in the histopathological findings for all the patients in the study (100 %), with the results of the laboratory tests proving normal. Differences in SWV were also observed between groups A, B and C: 1.34 ± 0.90 m/s, 1.55 ± 0.79 m/s and 1.86 ± 0.75 m/s (P < 0.001), respectively. The Az for differentiating NAFLD from NASH or fibrosis was 0.899 (optimal cut-off value 1.3 m/s; sensitivity 85 %; specificity 83.3 %). CONCLUSION: The ARFI technique is a useful diagnostic tool for differentiating NAFLD from NASH in asymptomatic patients with morbid obesity. KEY POINTS : • Acoustic radiation force impulse imaging provides ultrasonic shear wave velocity measurements. • SWV measurements were higher in patients with inflammation or fibrosis than NAFLD. • ARFI differentiates NAFLD from NASH in patients with morbid obesity. • Results suggest that ARFI can detect NASH in asymptomatic morbidly obese patients.

[Portal-splenic-mesenteric venous thrombosis secondary to a mutation of the prothrombin gene]. / Trombosis venosa portoesplenomesaraica secundaria a mutación del gen de la protrombina.

Thrombosis of the portal-mesenteric axis is an infrequent cause of intestinal ischemia or infarction. In addition to the multiple acquired factors that contribute to the development of this entity, hereditary risk factors, especially the factor V Leiden mutation and the G20210A mutation of the prothrombin gene, have been implicated. The G20210A mutation of the prothrombin gene is found in up to 40% of patients with splenic-portal-mesenteric thrombosis. The present case illustrates the unusual and nonspecific presentation of this mutation in the form of diarrhea and images of thrombosis of the superior mesenteric-portal vein and cavernous transformation of the portal vein. Delayed diagnosis is highly frequent since the clinical signs, laboratory investigations and radiological tests do not suggest the diagnosis. The patient received anticoagulant treatment and showed clinical improvement with complete portal-mesenteric recanalization. Currently the diagnostic technique of choice is magnetic resonance angiography or computerized tomography angiography and treatment consists of indefinite anticoagulation. This case illustrates that an unusual or atypical localization of venous thrombosis may be a manifestation of thrombophilia, emphasizing the importance of genetic screening in these cases.