Can serum interleukin-6 levels predict the outcome of patients with right iliac fossa pain?

In patients with right iliac fossa (RIF) pain it can be difficult to distinguish between appendicitis and nonspecific abdominal pain (NSAP). In this study we sought to determine whether serum interleukin-6 (IL-6) levels, an early marker of acute inflammation, taken at the time of admission could predict the outcome of patients admitted with RIF pain. Data were collected in a prospective manner on 53 consecutive patients (23 male, 30 female), mean age 22.1 years (range 10-79 years). Nineteen (36%) patients underwent surgery, of whom 16 had appendicitis (histologically proven). The mean (SEM) IL-6 levels (pg/ml) in patients undergoing operation vs those receiving non-operative management were 270.8 (106.3) vs 265.0 (80.4) (P = NS). The mean white blood cell (WBC) counts (x10(9)/l) in these patients were 14.28 (0.81) vs 9.66 (0.67), respectively (P = 0.0002). When patients with a confirmed diagnosis of appendicitis were compared with patients with a diagnosis of NSAP, the IL-6 levels were 149.4 (69.1) vs 363.6 (113.2), respectively (P = NS). In the same groups of patients, the WBC counts were 14.21 (0.81) vs 9.51 (0.68) (P = 0.004). We conclude that IL-6 levels taken at the time of admission are not useful in predicting the outcome of RIF pain.