[Lipoprotein (a) in liver diseases. Correlation between low levels and liver function]. / La lipoprotéine(a) dans les hépatopathies. Corrélation entre sa diminution et l'état fonctionnel du foie.

OBJECTIVES: To analyze the role of the liver function on the serum levels of lipoprotein(a) (Lp(a)), a lipoprotein considered to be a risk factor for atherosclerosis. METHODS: To measure the Lp(a) levels in patients with liver disease (n = 68) due to various causes and in patients with no liver disease and of similar age and sex-ratio (n = 62) and to analyze the relationship between Lp(a) levels on one hand and liver function and lipid and apoprotein levels on the other hand. RESULTS: Patients with liver disease had significantly lower levels of Lp(a). Lp(a) levels were significantly lower in patients with more severe liver disease (Child Turcotte classification) and significantly correlated with liver function tests, in particular those related to the microsomal function and the synthetic capacity of the liver (albumin, coagulation tests, apoprotein A-II). In patients with liver disease, mean Lp(a) levels were not significantly different between those with and those without chronic alcohol intake. CONCLUSIONS: Patients with liver disease have low levels of Lp(a) that are related to reduced synthetic capacity of this organ and are not linked to a specific cause of liver disease, in particular excess alcohol intake.

Hypoxic hepatitis in patients with cardiac failure: incidence in a coronary care unit and measurement of hepatic blood flow.

The incidence of hypoxic hepatitis was prospectively studied for 1 year in a group of high-risk patients suffering from low cardiac output in a coronary care unit. Hypoxic hepatitis, defined as an increase in serum aminotransferase activity of at least 20 times the upper limit of normal without any other cause for hepatic necrosis, was observed in 20 patients. This represents 2.6% of the 766 patients admitted to the unit during this period and 21.9% of the 91 patients suffering from low cardiac output. Clinical, biological and hemodynamic data were compared between 20 patients with low cardiac output and hypoxic hepatitis, and 48 patients with low cardiac output but without hypoxic hepatitis who survived more than 24 h. In these two groups of patients, hepatic blood flow was measured by galactose clearance at low concentration. Patients with hypoxic hepatitis exhibited a higher central venous pressure (90% versus 38%-p < 0.001) as well as a lower hepatic blood flow (867 +/- 377 ml/min versus 1429 +/- 644 ml/min-p = 0.001). In conclusion, although it is considered a rare hepatic disorder, hypoxic hepatitis is frequent in patients with low cardiac output admitted to the coronary care unit, and is associated with a decrease in hepatic blood flow and passive hepatic venous congestion.

Serum lipoprotein(a) in patients with diabetes mellitus.

OBJECTIVE: To investigate subjects with different types of diabetes mellitus regarding their serum levels of lipoprotein(a). High serum Lp(a) concentration is associated with a high risk of coronary heart disease. Diabetic patients are prone to developing coronary heart disease. RESEARCH DESIGN AND METHODS: The subjects were 66 type I diabetic patients, 100 type II diabetic patients treated with diet alone or diet combined with oral hypoglycemic agents, and 46 insulin-requiring type II diabetic patients. Subjects were compared with 142 nondiabetic outpatients. RESULTS: Subjects with insulin-requiring type II diabetes mellitus were found to have an increase both in serum Lp(a) concentration and in prevalence of serum Lp(a) concentration > 30 mg/dl compared with the other groups of diabetic patients and nondiabetic control subjects. A nonsignificant increase in the prevalence of coronary heart disease was also found in insulin-requiring type II diabetic patients. The levels of serum concentrations of Lp(a) were not significantly related to the degree of glycemic control, duration of diabetes, presence of macrovascular disease, or intake of female hormone therapy. High levels of Lp(a) in this group of diabetic patients could not be explained by the presence of albuminuria. CONCLUSIONS: Insulin-requiring type II diabetic patients have high levels of Lp(a). Chronic hyperinsulinemia might be an eventual causal factor.

The lipoprotein(a). Significance and relation to atherosclerosis.

Lipoprotein(a) has many similarities to low density lipoproteins but possesses a unique protein moiety called apolipoprotein(a). The plasma concentration of lipoprotein(a) is mainly under genetic control and most of diets and hypolipidemic drugs do not change its level. Only nicotinic acid and neomycin are able to reduce its concentration. Epidemiological studies suggest that high level (greater than 30 mg/dl) of lipoprotein(a) is an independent risk factor for atherosclerosis of the coronary and carotid arteries. The risk is highest in patients with hypercholesterolemia. The atherogenic role of lipoprotein(a) is attributed to the lack of its recognition by the cellular receptors and its consequent diversion to the atherogenic "non receptor" pathway. Due to its strong homology with plasminogen, lipoprotein(a) could also favour thrombosis. It is suggested that its determination is of importance when evaluating a patient with atherosclerosis. Reducing high plasma levels of cholesterolemia appears to be mandatory when plasma lipoprotein(a) concentration is higher than 30 mg/dl.