Elevated nitric oxide and endotoxemia in schistosonol hypertension

ABSTRACT

Nitric oxide [NO] is supposed to play a role in mediating vasodilatation and hyperdynamic circulation in liver cirrhosis and alcoholic hepatitis. It has been suggested that endotoxin might mediate increased synthesis of NO in endotoxemic patients with cirrhosis. The level of NO in schistosomal portal hypertension [SchPH] has not been studied, and whether endotoxemia plays a role in this condition is not known. To evaluate the level of NO and endotoxin in patients with schistosomal portal hypertension, and compare it to those in patients with post-necrotic cirrhosis and to normal individuals The study included 45 consenting patients; 27 with SchPH and living -schistosoma ova on rectal biopsy [11 Child A, 9 B, 7 C], and 1.8 with post-necrose cirrhosis [4 Child A, 6 B, 8 C]; and 15 healthy volunteers. Patients underwent upper GI endoscopy with grading of esophageal varices if present, ultrasonography with measurement of portal vein diameter, and liver biopsy. Patients and controls had plasma nitrite [NO[2]] measured as an indicator of NO production, and plasma endotoxin assayed by limulus amebocyte lysate test Patients with SchPH had significantly higher plasma NO[2] than controls [7.18 +/- 3 7 micro Mol/I vs 1.68 +/- 0.8 micro Mol/L p<0.005]. Endotoxin level was also significantly higher in SchPH than controls [0.46 +/- 0.09 Eu/ml vs. 0.15 +/- 0.05 Eu/ml. p < 0.05]. Non schistosomal patients had levels of NO[2] [6.3 +/- 3 micro Mol/L] and endotoxin [0.45 +/- 0.09 Eu/ml] similar to SchPH [both p > 0 05]. No difference was noted between Child classes in SchPH regarding NO[2] and endotoxin levels. NO[2] levels were positively correlated to the degree of portal hypertension assessed by portal vein diameter on ultrasound in SchPH. No correlation was found between NO[2] and endotoxin levels in SchPH [r = 0.48] SchPH is associated with increased NO production, and endotoxemia, similar to post-necrotic cirrhosis. The level of NO production increased with the severity of portal hypertension in this condition, and was not related to the level of endotoxemia