Pancreatic autoantibodies in Crohn's disease: a feasible diagnostic tool?

Idiopathic pancreatitis preceding the diagnosis of inflammatory bowel disease is more frequent in pediatric patients

BACKGROUND AND OBJECTIVES

Acute pancreatitis (AP) can be a rare extraintestinal manifestation of inflammatory bowel disease (IBD). There are only a few reports of AP presenting before the diagnosis of IBD. We aimed to characterize the demographic, clinical, and laboratory data of patients with IBD in whom AP preceded disease onset and compare the presentation of AP between children and adults.

PATIENTS AND METHODS

Pediatric and adult patients presenting with AP as the first symptom of IBD were retrospectively identified (10 years, 7 university hospitals). Demographic and clinical data, IBD type, disease extension, and laboratory data were extracted from the charts. Imaging methods, number of AP episodes, and lag time between onset of first pancreatitis episode and onset of IBD were recorded.

RESULTS

AP preceding the diagnosis of IBD was found in 10 in 460 pediatric patients with IBD (2.17%), compared with only 2 in 3500 adults (0.06%). Eight children had colonic disease (4 Crohn disease, 4 ulcerative colitis [3 pancolitis]). Mean amylase level was 1419 and range 100 to 1370. Three children (30%) had mildly elevated transaminases. Median time between onset of first episode of AP in relation to onset of IBD was 24 (range 1-156) weeks. AP most commonly presented with abdominal pain.

CONCLUSIONS

IBD presenting as AP was more frequent among the pediatric population with IBD in comparison to adults. It was more common in patients with colitis than in those with ileal disease, suggesting that patients with idiopathic AP should be observed carefully for a possible diagnosis of IBD.

Pancreatitis in inflammatory bowel diseases

Crohn's disease and ulcerative colitis, together popularly known as inflammatory bowel disease (IBD), are characterized by a number of extraintestinal manifestations. Although infrequent, acute pancreatitis, and less often chronic pancreatitis, may occur as a result of the disease itself or secondary to the medications used in the treatment. The increased incidence of acute pancreatitis in Crohn's disease can be explained based on the high predisposition to cholesterol as well as pigment stones as a result of ileal disease, anatomic abnormalities of the duodenum, immunologic disturbances associated with IBD, and, above all, to the side effects of many medications used in the treatment. Sulfasalazine, 5-aminosalicylic acid, azathioprine, and 6-mercaptopurine are well known to cause acute pancreatitis as a result of a possible idiosyncratic mechanism. Crohn's disease and ulcerative colitis share many clinical manifestations and treatment modalities. Nonspecific elevations of serum pancreatic enzymes in IBD make it difficult to avoid over diagnosis of acute pancreatitis, particularly in patients with Crohn's disease who suffer from abdominal pain often. The IBD-pancreas association is further reflected in many reports of exocrine as well as endocrine pancreatic insufficiency.

Quantification of antineural antibodies in autoimmune neurological disorders

More than 50 different neurological pathologies have a confirmed or suspected autoimmune etiology affecting an estimated number of 75 million people worldwide. Autoantibodies are a useful diagnostic marker for most autoimmune diseases even though their pathological role is not evident, and several tests for their detection are commercially available. However, for autoimmune diseases involving the nervous system, lack of clear information on the identity of antineural antibody targets and the presence of many rare diseases have hampered the development of specific diagnostic assays. This review focuses on the actual knowledge on confirmed and suspected autoimmune diseases that target the CNS and the diagnostic relevance of corresponding antineural autoantibodies.

Pancreatic autoantibodies in Greek patients with inflammatory bowel disease

Pancreatic autoantibodies (PAbs) have been suggested as a specific but not sensitive marker for Crohn's disease (CD). The aim of this study was to assess the value of detecting PAbs in Greek patients with ulcerative colitis (UC) and CD. Sera were collected from 150 patients with IBD (73 with UC and 77 with CD), 31 cases with non-IBD intestinal inflammation, 16 cases with other autoimmune diseases, and 104 healthy controls. Determination of PAbs was performed by a standard indirect immunofluorescence technique. PAbs were detected in 18 of 73 (24.7%) samples from UC patients and in 32 of 77 (41.6%) samples from CD patients. The prevalence of positive PAbs was significantly higher in CD than in UC (P = 0.04). None of the 104 samples from healthy controls and the 31 cases with non-IBD intestinal inflammation had detectable PAbs. One patient with Sjogren's syndrome was PAbs positive. No association of PAbs with IBD activity, IBD localization, or medical treatment was found. Patients with stenotic CD had a significantly higher prevalence of PAbs positivity (60%) compared with patients with inflammatory (28.6%) and fistulizing (41.2%) disease (P = 0.02). The prevalence of PAbs in Greek CD patients was found to be similar to that in previous reports. In contrast to these studies we found also increased prevalence of PAbs in UC patients. These findings suggest that PAbs should be considered as a specific marker for IBD rather than for CD.