[Dyslipidemia - when are lipid lowering medications useful in clinical practice?]

Dyslipidemia is one of the main modifiable cardiovascular risk factors. There is strong evidence for the efficacy of lipid-lowering drugs in secondary prevention, as well as in primary prevention for patients at high cardiovascular risk. In primary prevention, indication for lipid-lowering interventions should be based on an individual assessment of the cardiovascular risk and on the LDL cholesterol level, despite less strong evidence for the efficacy of drug-based interventions in low risk patients. Treatment consists of statins, as well as lifestyle modifications such as body weight control and increased physical exercise. The latter constitute the primary intervention in patients at low cardiovascular risk. Secondary dyslipidemias due to an underlying medical condition and familial dyslipidemias such as Familial Hypercholesterolemia and Familial Combined Hyperlipidemia should be identified and treated accordingly, taking into account that the risk scoring systems are not appropriate in these situations.

Multiple small "imaging" branch-duct type intraductal papillary mucinous neoplasms (IPMNs) in familial pancreatic cancer: indicator for concomitant high grade pancreatic intraepithelial neoplasia?

Most screening programs for familial pancreatic cancer are currently based on endoscopic ultrasonography and/or magnetic resonance imaging (MRI). Cystic lesions, especially those suspicious for small intraductal pancreatic mucinous neoplasms (IPMNs) of the branch ducts, can be visualized in up to 40 % of individuals at risk, but their pathological importance in the setting of FPC is yet not well established. Individuals at risk from a prospective screening program for familial pancreatic cancer with small "imaging" IPMNs of the branch-duct type (BD-IPMN) who underwent pancreatic resection were analysed regarding clinico-pathological data and the locations of pancreatic lesions. Five of 125 individuals at risk who underwent screening had multiple small (size 2-10 mm) unicystic lesions and/or multicystic single lesions in the pancreatic body and tail suspicious for BD-IPMNs upon MRI imaging and decided to undergo surgical resection after interdisciplinary counselling, although none fulfilled the consensus criteria for IPMN resection. Histological examination revealed BD-IPMNs with low or moderate dysplasia of the gastric type in combination with multifocal PanIN2 and PanIN3 lesions in 4 individuals. The remaining patient had only tiny ductectasias in the pancreatic tail with multifocal PanIN 2 lesions in the entire gland and one PanIN3 lesion in the pancreatic head. Intriguingly, the location of the most dysplastic histological lesions (PanIN3) did not correspond to the preoperatively detected lesions and were not visible in preoperative imaging. In the setting of FPC, the presence of multiple small "imaging" BD-IPMNs may indicate the presence of high-grade PanIN lesions elsewhere in the pancreas.

Fatal myocardial infarction at 4.5 years in a case of homozygous familial hypercholesterolaemia

Management of homozygous familial hypercholesterolaemia is notoriously difficult. For these patients, LDL apheresis is considered the treatment of choice. Treatment initiation is advocated generally from the age of seven years onwards (Thompson et al., Atherosclerosis 198:247-255, 2008). Here, we present the case of a young girl from a large inbred family of Turkish descent with homozygous familial hypercholesterolaemia and fatal outcome at the early age of 4(1/2) years.In conclusion, this case suggests that management of homozygous familial hypercholesterolaemia may require earlier and more aggressive treatment, including LDL apheresis before the age of seven years.

Xanthohumol ameliorates atherosclerotic plaque formation, hypercholesterolemia, and hepatic steatosis in ApoE-deficient mice

SCOPE: Xanthohumol (XN), a prenylated antioxidative and anti-inflammatory chalcone from hops, exhibits positive effects on lipid and glucose metabolism. Based on its favorable biological properties, we investigated whether XN attenuates atherosclerosis in western-type diet-fed apolipoprotein-E-deficient (ApoE(-/-) ) mice. METHODS AND RESULTS: XN supplementation markedly reduced plasma cholesterol concentrations, decreased atherosclerotic lesion area, and attenuated plasma concentrations of the proinflammatory cytokine monocyte chemoattractant protein 1. Decreased hepatic triglyceride and cholesterol content, activation of AMP-activated protein kinase, phosphorylation and inactivation of acetyl-CoA carboxylase, and reduced expression levels of mature sterol regulatory element-binding protein (SREBP)-2 and SREBP-1c mRNA indicate reduced lipogenesis in the liver of XN-fed ApoE(-/-) mice. Concomitant induction of hepatic mRNA expression of carnitine palmitoyltransferase-1a in ApoE(-/-) mice-administered XN suggests increased fatty acid beta-oxidation. Fecal cholesterol concentrations were also markedly increased in XN-fed ApoE(-/-) mice compared with mice fed western-type diet alone. CONCLUSION: The atheroprotective effects of XN might be attributed to combined beneficial effects on plasma cholesterol and monocyte chemoattractant protein 1 concentrations and hepatic lipid metabolism via activation of AMP-activated protein kinase.

Recurrent acute and chronic pancreatitis in two brothers with familial chylomicronemia syndrome

The chylomicronemia syndrome is well recognized as a rare etiologic factor of acute pancreatitis; however, whether hypertriglyceridemia can cause chronic pancreatitis (CP) remains unclear. We describe the long-time course of 2 brothers with the familial chylomicronemia syndrome caused by identical compound heterozygous mutations in the lipoprotein lipase (LPL) gene with markedly reduced LPL activity. Other etiologic factors were excluded, including mutations in the PRSS1, SPINK1, and CFTR gene. Although both brothers had recurrent acute pancreatitis and the same LPL genotype, CP became evident in only one patient. Progression to CP was associated with a more severe disease course. Thus, the chylomicronemia syndrome may cause CP in the absence of other known causative factors, and similar to alcoholic and hereditary CP, a more severe disease course is associated with disease progression.

Compositional protein analysis of high density lipoproteins in hypercholesterolemia by shotgun LC-MS/MS and probabilistic peptide scoring

A protein of a biological sample is usually quantified by immunological techniques based on antibodies. Mass spectrometry offers alternative approaches that are not dependent on antibody affinity and avidity, protein isoforms, quaternary structures, or steric hindrance of antibody-antigen recognition in case of multiprotein complexes. One approach is the use of stable isotope-labeled internal standards; another is the direct exploitation of mass spectrometric signals recorded by LC-MS/MS analysis of protein digests. Here we assessed the peptide match score summation index based on probabilistic peptide scores calculated by the PHENYX protein identification engine for absolute protein quantification in accordance with the protein abundance index as proposed by Mann and co-workers (Rappsilber, J., Ryder, U., Lamond, A. I., and Mann, M. (2002) Large-scale proteomic analysis of the human spliceosome. Genome Res. 12, 1231-1245). Using synthetic protein mixtures, we demonstrated that this approach works well, although proteins can have different response factors. Applied to high density lipoproteins (HDLs), this new approach compared favorably to alternative protein quantitation methods like UV detection of protein peaks separated by capillary electrophoresis or quantitation of protein spots on SDS-PAGE. We compared the protein composition of a well defined HDL density class isolated from plasma of seven hypercholesterolemia subjects having low or high HDL cholesterol with HDL from nine normolipidemia subjects. The quantitative protein patterns distinguished individuals according to the corresponding concentration and distribution of cholesterol from serum lipid measurements of the same samples and revealed that hypercholesterolemia in unrelated individuals is the result of different deficiencies. The presented approach is complementary to HDL lipid analysis; does not rely on complicated sample treatment, e.g. chemical reactions, or antibodies; and can be used for projective clinical studies of larger patient groups.

Somatic CEBPA mutations are a frequent second event in families with germline CEBPA mutations and familial acute myeloid leukemia

PURPOSE: The transcription factor CCAAT/enhancer binding protein-alpha (CEBPA) is crucial for normal myeloid differentiation. Mutations in the CEBPA gene are found in subsets of patients with acute myeloid leukemia (AML). Recently, three families were reported in whom several family members had germline CEBPA mutations and subsequently developed AML. Whereas familial AML is considered a rare event, the frequency of CEBPA germline mutations in AML is not known. PATIENTS AND METHODS: In this study, we screened 187 consecutive AML patients for CEBPA mutations at diagnosis. We detected 18 patients (9.6%) with CEBPA mutations. We then analyzed remission samples and constitutive DNA from these patients. RESULTS: We found that two (11.1%) of 18 AML patients with CEBPA mutations carried a germline N-terminal frameshift CEBPA mutation. Interestingly, additional members in the families of both of these patients have been affected by AML, and the germline CEBPA mutations were also observed in these patients. Additional somatic mutations in AML patients with germline CEBPA mutations in the two families comprised in-frame C-terminal CEBPA mutations in two patients, two nonsilent CEBPA point mutations in one patient, and monosomy 7 in one patient. CONCLUSION: This study shows, for the first time to our knowledge, that germline CEBPA mutations are frequently observed among AML patients with CEBPA mutations. Including the families with germline CEBPA mutations reported previously, additional somatic CEBPA mutations represent a frequent second event in AML with germline CEBPA mutations. Our data strongly indicate that germline CEBPA mutations predispose to AML and that additional somatic CEBPA mutations contribute to the development of the disease.

Treatment of hypercholesterolemia in patients with primary biliary cirrhosis might be more beneficial than indicated

Cholesterol circulating levels are elevated in most of the patients with primary biliary cirrhosis. This review questions whether hypercholesterolaemia represents a cardiovascular risk in primary biliary cirrhosis and whether it should be treated. The published evidence indicates that hypercholesterolaemia in patients with primary biliary cirrhosis should be considered a cardiovascular risk factor only when other factors are present. Ursodeoxycholic acid the standard treatment of primary biliary cirrhosis improves the cholestasis and hereby lowers circulating levels of cholesterol. Primary biliary cirrhosis is not a contraindication to prescribe statins or fibrates to these patients. Interestingly, these two classes of drugs have been shown to improve not only the lipid profile but also the liver tests. In particular fibrates have been found to normalize liver tests in patients responding incompletely to ursodeoxycholic acid. Statins as well as fibrates possess specific anti-inflammatory properties which may be beneficial in primary biliary cirrhosis. In conclusion, hypercholesterolaemia in the absence of other cardiovascular risk factors does not require specific therapeutic intervention in patients with primary biliary cirrhosis. However, statins as well as fibrates seem to have beneficial effects on the primary biliary cirrhosis itself and deserve formal testing within clinical trials.

Electroencephalographic changes and seizures in familial hemiplegic migraine patients with the CACNA1A gene S218L mutation

The S218L CACNA1A mutation has been previously described in two families with familial hemiplegic migraine. We present three siblings with the mutation with the novel association of childhood seizures, and highlight the dynamic changes seen on electroencephalography during hemiplegic migraine attacks. Depressed activity contralateral to the hemiparesis was seen on electroencephalography during acute hemiplegic migraine attacks, which may be due to changes to calcium channels caused by the S218L mutation. Both parents were asymptomatic and did not carry the S218L mutation in their blood. This suggests the presence of mosaicism in the transmitting parent.

Atorvastatin compared with simvastatin-based therapies in the management of severe familial hyperlipidaemias

We compared atorvastatin with simvastatin-based therapies in a prospective observational study of 201 patients with severe hyperlipidaemia. Atorvastatin 10 mg therapy was substituted for simvastatin 20 mg, 20 mg for 40 mg, 40 mg for simvastatin 40 mg plus resin, and 80 mg for simvastatin-fibrate-resin therapy. Lipid and safety profiles were assessed. Atorvastatin reduced total cholesterol by 31 +/- 11-40 +/- 14% vs. 25 +/- 12-31 +/- 11%; LDL by 38 +/- 16-45 +/- 18% vs. 31 +/- 18-39 +/- 18% and geometric mean triglycerides by 29.3-37.3% vs. 16.6-24.8%, but reduced HDL 11% +/- 47% at 80 mg compared with a 16% +/- 34% increase with simvastatin-based therapy. Target LDL < 3.5 mmol/l was achieved more often with atorvastatin (63% vs. 50%; p < 0.001). Atorvastatin increased geometric mean fibrinogen by 12-20% vs. a 0-6% fall with simvastatin (p << 0.001). Side effects were noted in 10-36% of patients, including one case of rhabdomyolysis, and 36% discontinued therapy. These data suggest that atorvastatin is more effective than current simvastatin-based therapies in achieving treatment targets in patients with familial hypercholesterolaemia but at the expense of a possible increase in side-effects. This issue needs further study in randomized controlled trials.