Botryoid rhabdomyosarcoma of the biliary tract in children: a unique case report.

Rhabdomyosarcoma (RMS) is the most common tumour of the biliary tree in childhood. In children, it is a rare lesion, accounting for about 1% of all RMS. Hepatobiliary botryoid RMS is a disease affecting young children at a median age of about 3 years. In literature, the radiological findings of hepatobiliary RMS have been described in small series and some case reports. In this case report, we present a rare case of RMS of the extrahepatic biliary tree initially diagnosed as a choledochal cyst.

Dopamine "renal dose" versus fenoldopam mesylate to prevent ischemia-reperfusion injury in renal transplantation.

Low dose of dopamine is commonly used after kidney transplantation as a reno-protective agent, although its benefits are controversial. Dopamine may increase renal blood flow, decrease resistive index (RI), and induce urine output in normal kidneys. Many authors hypothesized that the vasculature of a denervated renal transplant may not respond to dopamine in the same fashion as healthy native kidneys, which led us to find other drugs to attenuate the ischemia-reperfusion (I/R) injury. Fenoldopam is a selective dopamine1 (DA1) receptor agonist, most of the activity of which resides in the R-enantiomer, which also shows weaker alpha 2-adrenoceptor antagonist activities. Fenoldopam produces a vasidilatory effect in vascular beds that are rich in vascular DA1 receptors, producing increased renal blood flow at doses that do not affect blood pressure. In addition to its renal vasodilator activity, fenoldopam is natriuretic, possibly resulting from a direct effect of DA1 receptors on the proximal convoluted tubule. In animals with spontaneous or drug-induced renal failure, fenoldopam improves renal function. The aim of this study was to investigate the possible effects of fenoldopan mesylate in recent kidney transplants. Creatinine, blood urea nitrogen, urine output, and renal vascular resistive index (IR) were measured using Doppler ultrasound. Two groups of patients with no statistical differences in demographic data were treated with dopamine or fenoldopan, showing no significant difference but a trend favoring the fenoldopan group.

Cerebral hemodynamic and metabolic changes in patients with fulminant hepatic failure during liver transplantation.

BACKGROUND: Cerebral autoregulation and metabolism may be seriously compromised in patients with fulminant hepatic failure (FHF). The mechanism responsible for the alteration in cerebral blood flow (CBF) has not been yet clearly defined; however, it is known that it does correlate with liver function. Orthotopic liver transplant (OLT) rapidly restores normal liver function, but little is known about the restoration of cerebral metabolism and hemodynamics. To investigate the relationship between liver function and CBF, we evaluated autoregulation and metabolic changes during OLT in six patients comatose due to FHF. METHODS: We evaluated autoregulation based on a linear regression analysis between mean arterial blood pressure and parallel CBF velocity (CBFV) changes using transcranial Doppler ultrasound. Cerebral metabolism rate was estimated by the arterial-jugular venous oxygen content difference (a-jDO2), while the percentile variation in cerebral metabolic rate for oxygen (CMRO2) was estimated using CBFV percentile variation rather than CBF percentile variation (eCMRO2). RESULTS: Prior to transplant autoregulation was impaired in all patients. However it markedly improved at the end of surgery (P <.05). The eCMRO2 improved as well, particularly among subjects who displayed prompt neurological recovery. In all patients the a-jDO2 was low before transplantation increasing to normal values at the end of surgery. CONCLUSIONS: A hallmark of FHF seems to be failure of autoregulation, which is linked to uncoupling between CBF and CMRO2 as attested by an a-jDO2 lower than normal in all patients (luxury perfusion). The recovery of liver function rapidly improves cerebral hemodynamics and metabolic stability. The study of autoregulation and eCMRO2 recovery using Doppler monitoring proffers the possibility to predict early graft function after liver reperfusion. In our patients eCMRO2 seemed to be associated with improved neurological outcomes.