[Oral contraceptive-induced pancreatitis in the hyperchylomicronemia syndrome]

Combined hormonal contraceptive use among women with known dyslipidemias: a systematic review of critical safety outcomes

CONTEXT

Dyslipidemias represent a spectrum of lipid disorders that are important risk factors for cardiovascular disease. In addition, elevated triglycerides are known to be associated with pancreatitis. Though less clear, it is possible that dyslipidemias may also contribute to risk for venous thromboembolism (VTE). Ethinyl estradiol and progestogen, contained within combined hormonal contraception, are known to impact lipid metabolism.

OBJECTIVES

To evaluate from the literature whether use of combined hormonal contraception (CHC), including combined oral contraception (COC) pills, transdermal patch, vaginal ring or injectables, modifies the relative risk of acute myocardial infarction (MI), stroke, VTE or pancreatitis among women with known dyslipidemias and to determine if existing lipid abnormalities worsen with CHC use.

METHODS

PubMed and the Cochrane Library databases were searched for all articles in all languages published between inception and September 2014 relevant to dyslipidemia, CHC use and serious adverse events (MI, stroke, VTE or pancreatitis). The quality of each individual study was assessed using the system for grading evidence developed by the United States Preventive Services Task Force.

RESULTS

From 306 articles identified by our search strategy, 3 articles met inclusion criteria. In a poor-quality case-control study, women with hypercholesterolemia but no COC use had an increased risk of MI (adjusted odds ratio [adj OR] 3.3, 95% confidence interval [CI] 1.6-6.8), as did women who used COCs but did not have hypercholesterolemia (adj OR 2.0, 95% CI 1.4-2.8), compared with non-COC users without hypercholesterolemia; women with both COC use and hypercholesterolemia had an adjusted OR of 24.7 (95% CI 5.6-108.5) compared with women with neither risk factor. A poor-quality cohort study examined COC users and reported that women with dyslipidemia had increased risk for VTE [crude risk ratio (RR) 1.39, 95% CI 1.04-1.85] and transient ischemic attacks or cerebrovascular accidents (CVAs) (RR 1.76, 95% CI 1.51-2.06) compared to those without dyslipidemia. Another poor-quality cohort study provided direct evidence on changes in lipid levels among COC users with dyslipidemia. A minority of women with elevated total cholesterol or triglyceride levels at baseline showed normal results (25% and 28%, respectively) after 6 cycles of COC use. No evidence regarding risks associated with use of other CHC methods was identified. No evidence was identified for the outcome of pancreatitis.

CONCLUSION

Limited data from poor-quality observational studies suggest that women with known dyslipidemias using CHC may be at increased risk for MI and may experience a minimal increase in risk for CVA or VTE. No evidence was identified on risk for pancreatitis in this context. The impact of CHC exposure on the status of lipid abnormalities over time, an intermediate marker for disease, is also unclear. Given the significant limitations of this body of evidence, the importance of access to effective contraception and theoretical concerns raised about the use of CHCs by women with known dyslipidemias, additional rigorous studies are needed to best estimate true associations. Contraceptive decision making should include consideration of both the known and theoretical risks of a given CHC method, safety and acceptability of alternative contraceptive methods, and risks associated with unintended pregnancy.

The pancreas-specific protein disulphide-isomerase PDIp interacts with a hydroxyaryl group in ligands

Using a cross-linking approach, we have recently demonstrated that radiolabelled model peptides or misfolded proteins specifically interact in vitro with two members of the protein disulphide- isomerase family, namely PDI and PDIp, in a crude extract from sheep pancreas microsomes. In addition, we have shown that tyrosine and tryptophan residues within a peptide are the recognition motifs for the binding to PDIp. Here we examine non-peptide ligands and present evidence that a hydroxyaryl group is a structural motif for the binding to PDIp; simple constructs containing this group and certain xenobiotics and phytoestrogens, which contain an unmodified hydroxyaryl group, can all efficiently inhibit peptide binding to PDIp. To our knowledge this is the first time that the recognition motif of a molecular chaperone or folding catalyst has been specified as a simple chemical structure.

Therapeutic plasma exchange in patients with chylomicronemia syndrome complicated by acute pancreatitis

Chylomicronemia syndrome (CMS) is a rare disorder characterized by the presence of chylomicrons in the fasting state causing a milky appearance of plasma, eruptive xanthomas, and hepatosplenomegaly; an acute and potentially life threatening complication is severe acute pancreatitis. The underlying defects are inborn errors of metabolism such as deficiencies of lipoprotein lipase (LPL) or apoprotein C-II (apo C-II) as well as familial hypertriglyceridemia. Moreover, CMS can be precipitated when mild hypertriglyceridemia is exacerbated by additional factors such diabetes mellitus, ethanol abuse, or pregnancy. The purpose of the present study was to retrospectively analyze the results of therapeutic plasma exchange (TPE) in 5 patients transferred to our hospital for severe acute pancreatitis due to chylomicronemia syndrome. In a total of 7 TPE sessions, on average 3,286 +/- 247 ml of plasma (i.e., about 1 patient plasma volume) were treated per session. Triglyceride (TG) levels were decreased from 4,972 +/- 2,469 mg/dl on admission to 1,614 +/- 1,276 mg/dl (-70%) after the TPE sessions, and a further decrease was achieved by conservative treatment. Part of the TG reducing effect of the treatment was probably due to heparin induced lipolysis. Acute pancreatitis was resolved in all cases, and 1 pregnant patient delivered without problems at term. In summary, 1 or 2 TPE sessions sufficed to substantially decrease the bulk of triglycerides in acutely exacerbated chylomicronemia syndrome causing a rapid resolution of acute severe pancreatitis.

Familial lipoprotein lipase deficiency in infancy: clinical, biochemical, and molecular study

OBJECTIVES

To describe the characteristics of lipoprotein lipase (LPL)-deficient patients seen in infancy and to evaluate the safety and efficacy of severe fat restriction.

METHODS

Children <1 year old presenting with chylomicronemia between 1972 and 1995 were identified, and their clinical courses were reviewed retrospectively.

RESULTS

LPL deficiency was demonstrated in 16 infants who presented with irritability (n = 7), lower intestinal bleeding (n = 2), pallor, anemia, or splenomegaly (n = 5), and a family history or fortuitous discovery (n = 2). All plasma samples were lactescent at presentation. Chylomicronemia responded rapidly to dietary fat restriction, and it was possible to maintain satisfactory metabolic control for a prolonged period of time. Only 1 adolescent girl had an episode of pancreatitis associated with the use of oral contraceptives. No persistent adverse effects on growth were seen. We obtained abnormal values for serum iron, alkaline phosphatase, and total calcium.

CONCLUSIONS

The presentation of LPL deficiency is heterogeneous during infancy. Close dietary monitoring is required to avoid nutritional deficiencies. Estrogen therapy should be avoided in LPL-deficient patients.

Drug-induced pancreatitis

Few data exist about the incidence of drug-induced pancreatitis in the general population. 20 cases of drug-related pancreatitis were reported in Switzerland over a period of 12 years. The proportion of cases of pancreatitis caused by drugs is estimated to be around 2% in the general population, with much higher proportions in specific subpopulations, such as children and patients who are HIV positive. The literature about drug-induced pancreatitis consists mainly of anecdotal case reports. Clear evidence of a definite association with pancreatitis, by means of rechallenge tests, or consistent case reports, supported by animal experiments or data on the incidence of acute pancreatitis in drug trials exists for didanosine, valproic acid (sodium valproate), aminosalicylates, estrogen, calcium, anticholinesterases and sodium stibogluconate. An association with drug-induced pancreatitis is likely but not definitely proven for thiazide diuretics, pentamidine, ACE inhibitors, asparaginase, vinca alkaloids, some nonsteroidal anti-inflammatory drugs and clozapine. Pancreatitis is possibly caused by azathioprine, furosemide (frusemide), tetracycline, metronidazole, isoniazid, rifampicin (rifampin), sulphonamides, cyclosporin and some antineoplastic drugs. Many drugs have been reported to be associated with acute pancreatitis. However, lack of rechallenge evidence, consistent statistical data, or evidence from experimental studies on a possible mechanism prohibit definitive conclusions about most of them. The high incidence of concurrent illnesses known to induce acute pancreatitis, makes a trigger role or co-factor role for the drug seem most likely.