Leukotriene b4, acute abdominal familial mediterranean fever and acute abdominal pain from other etiologies

Abstract

Study objectives: Familial Mediterranean fever (FMF) or familial paroxysmal polyserositis, an autosomal recessive disease, is a frequent etiology for acute abdominal pain in febrile patients arriving at emergency departments (EDs) attending areas with a high rate of population from Mediterranean extraction. Diagnosing acute peritonitis as a peritoneal FMF attack is extremely important because its nature is benign and its treatment medical, whereas other etiologies may be life threatening and require a different medical approach and, frequently, surgical intervention. An accurate and feasible test that corroborates acute abdominal FMF may prevent unnecessary abdominal surgery. Lipoxygenase products are present in the serum and synovial fluid of FMF patients (6), and attacks may be prevented or reduced in frequency by dietary fat restriction (7-11) or by colchicine therapy (12, 13); lipocortin defect has been suggested as a potential cause of phospholipase A2 release of arachidonic acid and its subsequent cyclooxygenase- and lipoxygenase-mediated eicanoside derivatives. Eicanoside generation, especially prostaglandin E2, prostacyclin, and leukotriene B4, has a potent proinflammatory effect that could be responsible for symptoms occurring during an acute attack. Methods: Urine samples were collected from consecutive patients arriving at the ED for right lower quadrant abdominal pain and tested for leukotriene B4 (LTB4). Clinical follow-up, computed tomography, and ultrasonographic examinations, as well as pathology results, were analyzed, and patients were classified into 4 groups: acute appendicitis, urinary conditions, nonspecific abdominal pain, and acute FMF. Results: Urine samples from 17 healthy individuals and from 36 patients with right lower quadrant abdominal pain and presenting to the ED were examined for LTB4 concentrations. Mean LTB4 concentrations were as follows: acute FMF 328±237 pg/mg chromium, nonspecific abdominal pain 297±173 pg/mg chromium, acute appendicitis 261±105 pg/mg chromium, urologic conditions 244±64 pg/mg chromium, controls 210±62 pg/mg chromium. Conclusion: LTB4 level is high in acute abdominal conditions, especially in acute FMF (<i>P</i><.032). Although significant differences in urine LTB4 levels were found between acute FMF and the control group, urine LTB4 levels were also high in right lower quadrant abdominal pain from other etiologies, the differences being insignificant. Our findings suggest a role of the lipocortin pathway in acute FMF but suggest that urine LTB4 is not specific enough to differentiate acute FMF from other conditions presenting with right lower quadrant abdominal pain, and especially acute appendicitis.