Urine leukotriene B4 in familial Mediterranean fever and other forms of right lower abdominal pain.

BACKGROUND: Acute right lower abdominal pain may present a diagnostic dilemma. Leukotrienes have been found to be elevated in familial Mediterranean fever (FMF), a disease manifesting with recurrent episodes of "acute abdomen." OBJECTIVES: To determine whether urine leukotriene B4 (LTB4) may differentiate between an FMF attack and some other forms of acute right lower abdominal pain. METHODS: The LTB4 level was determined, using a commercial enzyme-linked immunosorbent assay (ELISA), in urine samples obtained from 36 patients with acute (< 24 hours) right lower abdominal pain presenting to the emergency department, and from 18 healthy volunteers. RESULTS: Compared with the healthy control subjects, LTB4 was significantly higher in those who had FMF (12 patients, p < 0.03). In other forms of acute right lower abdominal pain, including appendicitis (eight patients), urologic disorders (eight patients), and nonspecific abdominal pain (eight patients), intermediate levels of LTB4 were observed, not significantly different from those of either FMF patients or healthy control subjects. CONCLUSIONS: In the samples tested, urine LTB4 levels were not instrumental in differentiating FMF from other acute right lower abdominal pain.

Effect of elevated homocysteine levels on clinical restenosis following percutaneous coronary intervention.

Since hyperhomocysteinemia confers a prothrombotic effect and promotes proliferation of smooth muscle cells in response to vascular injury, it might be implicated in the pathogenesis of restenosis after percutaneous coronary intervention (PCI). Our study comprised 55 patients who underwent successful PCI in the acute myocardial infarction (AMI) course. Homocysteine levels were determined within 24 h of admission. During a 1-year follow-up, 16 patients (31%) underwent repeated coronary angiography for recurrent angina or re-infarction, which demonstrated re-narrowing of > or =50% at the qualifying PCI site (clinical restenosis). Irrespective of stent deployment, clinical restenosis was not associated with higher homocysteine levels (12 +/- 7 vs. 14 +/- 11 micromol/l, p = 0.77). There was no correlation between homocysteine levels and time to restenosis (r(2) = 0.06, p = 0.35). In conclusion, elevated homocysteine levels do not predict a higher incidence of restenosis after PCI.