Acute pancreatitis associated with rofecoxib

Ever-increasing diversity of drug-induced pancreatitis

With over 100000 hospital admissions per annum, acute pancreatitis remains the leading gastrointestinal cause of hospitalization in the United States and has far-reaching impact well beyond. It has become increasingly recognized that drug-induced pancreatitis (DIP), despite accounting for less than 3% of all cases, represents an important and growing though often inconspicuous cause of acute pancreatitis. Nevertheless, knowledge of DIP is often curtailed by the limited availability of evidence needed to implicate given agents, especially for non-prescription medications. Indeed, the majority of available data is derived from case reports, case series, or case control studies. Furthermore, the mechanism of injury and causality for many of these drugs remain elusive as a definitive correlation is generally not established (< 10% of cases). Several classification systems have been proposed, but no single system has been widely adopted, and periodic updates are required in light of ongoing pharmacologic expansion. Moreover, infrequently prescribed medications or those available over-the-counter (including herbal and other alternative remedies) are often overlooked as a potential culprit of acute pancreatitis. Herein, we review the ever-increasing diversity of DIP and the potential mechanisms of injury with the goal of raising awareness regarding the nature and magnitude of this entity. We believe this manuscript will aid in increasing both primary and secondary prevention of DIP, thus ultimately facilitating more expedient diagnosis and a decrease in DIP-related morbidity.

Drug induced pancreatitis: A systematic review of case reports to determine potential drug associations

OBJECTIVE

A current assessment of case reports of possible drug-induced pancreatitis is needed. We systematically reviewed the case report literature to identify drugs with potential associations with acute pancreatitis and the burden of evidence supporting these associations.

METHODS

A protocol was developed a priori (PROSPERO CRD42017060473). We searched MEDLINE, Embase, the Cochrane Library, and additional sources to identify cases of drug-induced pancreatitis that met accepted diagnostic criteria of acute pancreatitis. Cases caused by multiple drugs or combination therapy were excluded. Established systematic review methods were used for screening and data extraction. A classification system for associated drugs was developed a priori based upon the number of cases, re-challenge, exclusion of non-drug causes of acute pancreatitis, and consistency of latency.

RESULTS

Seven-hundred and thirteen cases of potential drug-induced pancreatitis were identified, implicating 213 unique drugs. The evidence base was poor: exclusion of non-drug causes of acute pancreatitis was incomplete or poorly reported in all cases, 47% had at least one underlying condition predisposing to acute pancreatitis, and causality assessment was not conducted in 81%. Forty-five drugs (21%) were classified as having the highest level of evidence regarding their association with acute pancreatitis; causality was deemed to be probable or definite for 19 of these drugs (42%). Fifty-seven drugs (27%) had the lowest level of evidence regarding an association with acute pancreatitis, being implicated in single case reports, without exclusion of other causes of acute pancreatitis.

DISCUSSION

Much of the case report evidence upon which drug-induced pancreatitis associations are based is tenuous. A greater emphasis on exclusion of all non-drug causes of acute pancreatitis and on quality reporting would improve the evidence base. It should be recognized that reviews of case reports, are valuable scoping tools but have limited strength to establish drug-induced pancreatitis associations.

REGISTRATION

CRD42017060473.

Advances in understanding the role of cyclooxygenase-2 in the pathogenesis of acute pancreatitis

Activation and release of digestive enzymes and pancreatic microcirculatory disturbance are initiators of acute pancreatitis. The expression of cyclooxygenase-2 (COX-2) has been detected in inflammatory response induced by many stimulating factors. COX-2 can promote the development of early inflammation and induce pancreatic microcirculatory disturbance.

NSAIDs and Acute Pancreatitis: A Systematic Review

The resulting pain is the main symptom of acute pancreatitis and it should be alleviated as soon as possible. NSAIDs are the first line therapy for pain and they are generally administered to acute pancreatitis patients upon admission to the hospital. In addition, these drugs have also been used to prevent post-endoscopic cholangiopancreatography (ERCP) acute pancreatitis. On the other hand, there are several reports indicating that NSAIDs may be the actual cause of acute pancreatitis. We carried out a literature search on PubMed/MEDLINE; all full text papers published in from January 1966 to November 2009 on the use of NSAIDs in acute pancreatitis were collected; the literature search was also supplemented by a review of the bibliographies of the papers evaluated. Thus, in this article, we will systematically review the current literature in order to better illustrate the role of NSAIDs in acute pancreatitis, in particular: i) NSAIDs as a cause of acute pancreatitis; ii) their use to prevent post-retrograde ERCP pancreatitis and iii) their efficacy for pain relief in the acute illness of the pancreas.

Pharmacological approach to acute pancreatitis

The aim of the present review is to summarize the current knowledge regarding pharmacological prevention and treatment of acute pancreatitis (AP) based on experimental animal models and clinical trials. Somatostatin (SS) and octreotide inhibit the exocrine production of pancreatic enzymes and may be useful as prophylaxis against Post Endoscopic retrograde cholangiopancreatography Pancreatitis (PEP). The protease inhibitor Gabexate mesilate (GM) is used routinely as treatment to AP in some countries, but randomized clinical trials and a meta-analysis do not support this practice. Nitroglycerin (NGL) is a nitrogen oxide (NO) donor, which relaxes the sphincter of Oddi. Studies show conflicting results when applied prior to ERCP and a large multicenter randomized study is warranted. Steroids administered as prophylaxis against PEP has been validated without effect in several randomized trials. The non-steroidal anti-inflammatory drugs (NSAID) indomethacin and diclofenac have in randomized studies showed potential as prophylaxis against PEP. Interleukin 10 (IL-10) is a cytokine with anti-inflammatory properties but two trials testing IL-10 as prophylaxis to PEP have returned conflicting results. Antibodies against tumor necrosis factor-alpha (TNF-α) have a potential as rescue therapy but no clinical trials are currently being conducted. The antibiotics beta-lactams and quinolones reduce mortality when necrosis is present in pancreas and may also reduce incidence of infected necrosis. Evidence based pharmacological treatment of AP is limited and studies on the effect of potent anti-inflammatory drugs are warranted.

Role of nuclear receptors in the adaptive response to bile acids and cholestasis: pathogenetic and therapeutic considerations

Cholestasis results in intrahepatic accumulation of cytotoxic bile acids which cause liver injury ultimately leading to biliary fibrosis and cirrhosis. Cholestatic liver damage is counteracted by a variety of intrinsic hepatoprotective mechanisms. Such defense mechanisms include repression of hepatic bile acid uptake and de novo bile acid synthesis. Furthermore, phase I and II bile acid detoxification is induced rendering bile acids more hydrophilic. In addition to "orthograde" export via canalicular export systems, these compounds are also excreted via basolateral "alternative" export systems into the systemic circulation followed by renal elimination. Passive glomerular filtration of hydrophilic bile acids, active renal tubular secretion, and repression of tubular bile acid reabsorption facilitate renal bile acid elimination during cholestasis. The underlying molecular mechanisms are mediated mainly at a transcriptional level via a complex network involving nuclear receptors and other transcription factors. So far, the farnesoid X receptor FXR, pregnane X receptor PXR, and vitamin D receptor VDR have been identified as nuclear receptors for bile acids. However, the intrinsic adaptive response to bile acids cannot fully prevent liver injury in cholestasis. Therefore, additional therapeutic strategies such as targeted activation of nuclear receptors are needed to enhance the hepatic defense against toxic bile acids.

Inhibition of cyclooxygenase-2 in experimental severe acute pancreatitis

BACKGROUND

The standard treatment for acute pancreatitis (AP) is still based on supportive care. The search for a new drug that could change the natural history of the disease is a continuing challenge for many researchers. The aim of this study is to evaluate the effect of a cyclooxygenase-2 (COX-2) inhibitor on experimental AP in rats.

METHODS

The animals were divided into 2 groups: Group 1 (n = 30)-animals with taurocholate-induced AP treated with parecoxib (40 mg/kg). Group 2 (n = 30)-animals with taurocholate-induced AP that received saline. The COX-2 inhibitor (parecoxib) was injected immediately after AP induction, through the penis dorsal vein. The parameters evaluated were histology, serum levels of amylase, IL-6 and IL-10, and mortality rate.

RESULTS

The serum levels of IL-6 and IL-10 in the parecoxib-treated group were lower than the control group. The amylase serum levels and the mortality rate remained unchanged in the treated animals. Histologic morphology also was unaltered, except for fat necrosis, which was higher in parecoxib-treated rats.

CONCLUSION

Inhibition of Cox-2 decreases the systemic release of inflammatory cytokines, but has a poor effect on the direct pancreas injury caused by taurocholate.

Rofecoxib: an update on physicochemical, pharmaceutical, pharmacodynamic and pharmacokinetic aspects

Rofecoxib (MK-966) is a new generation non-steroidal anti-inflammatory agent (NSAID) that exhibits promising anti-inflammatory, analgesic and antipyretic activity. It selectively inhibits cyclooxygenase (COX)-2 isoenzyme in a dose-dependent manner in man. No significant inhibition of COX-1 is observed with rofecoxib up to doses of 1000 mg. The pharmacokinetics of rofecoxib has been found to be complex and variable. Mean oral bioavailability after single dose of rofecoxib (12.5, 25 or 50 mg) is 93% with t(max) varying widely between 2 and 9 h. It is highly plasma-protein bound and is metabolized primarily by cytosolic reductases to inactive metabolites. Rofecoxib is eliminated predominantly by hepatic metabolism with a terminal half-life of approximately 17 h during steady state. Various experimental models and clinical studies have demonstrated rofecoxib to be superior, or at least equivalent, in anti-inflammatory, analgesic and antipyretic efficacy to comparator nonselective NSAIDs in osteoarthritis, rheumatoid arthritis and other pain models. Emerging evidence suggests that rofecoxib may also find potential use as supportive therapy in various pathophysiologic conditions like Alzheimer's disease, and in various malignant tumours and polyps, where COX-2 is overly expressed. Rofecoxib is generally well-tolerated. Analysis of data pooled from several trials suggests that rofecoxib is associated with fewer incidences of clinically symptomatic gastrointestinal ulcers and ulcer complications vis-à-vis conventional NSAIDs. However, this gastropreserving effect may be negated by concurrent use of low-dose aspirin for cardiovascular risk reduction. Rofecoxib tends to show similar tolerability for renal and cardiothrombotic events as compared with nonnaproxen nonselective NSAIDs. No clinically significant drug interaction has been reported for rofecoxib except with diuretics, where it reverses their salt-wasting effect and thus can be clinically exploited in electrolyte-wasting disorders. There is only modest information about the physicochemical and pharmaceutical aspects of rofecoxib. Being poorly water soluble, its drug delivery has been improved using varied formulation approaches. Although it is stable in solid state, rofecoxib is photosensitive and base-sensitive in solution form with its degradation mechanistics elucidated. Analytical determinations of rofecoxib and its metabolites in biological fluids employing HPLC with varied types of detectors have been reported. Isolated studies have also been published on the chromatographic and spectrophotometric assay of rofecoxib and its degradants in bulk samples and pharmaceutical dosage forms. The current article provides an updated overview on the physicochemical, pharmaceutical, pharmacokinetic and pharmacodynamic vistas of rofecoxib.

Pharmacoepidemiology and rheumatic diseases: 2001-2002

Pharmacoepidemiology is the branch of epidemiology that focuses on medications and their outcomes, including both adverse events and intended consequences. Such studies have become more prominent in rheumatology as the number of new medications has grown and prescribing databases have become more available. In the past year, the potential cardiovascular complications associated with selective COX-2 inhibitors have become an important concern. A number of pooled analyses suggest the possibility of an increased risk of acute myocardial infarction, and studies of naproxen have found a possible protective effect. Accumulating evidence supports the contention that early initiation of disease modifying antirheumatid drug therapy improves outcomes of patients with rheumatoid arthritis. Open-label extensions of biologic therapies found continued benefits extending several years with the TNF-alpha antagonists, but concerns have arisen regarding tuberculosis and central nervous system demyelination with these agents. Data continue to be published quantifying the risk of osteoporosis associated with glucocorticoids, and the association between biphosphonate therapy and upper gastrointestinal events appears to be less of a concern that originally described.