Campylobacter jejuni: clinical and diagnostic value of serum antibody titres

Eighty patients with either bacteriologically confirmed Campylobacter jejuni infection and/or an antibody titre value of at least 1:80, determined by ELISA, were studied. A significant correlation was found between titre value and severity of symptoms (P = 0.015). Although a correlation was noted between symptoms score and endoscopic abnormalities, this was not quite statistically significant (P = 0.053). Comparison of patients with a titre of at least 1:1280 and those with lower titre values revealed a significantly higher symptom score (P = 0.019) and endoscopic score (P = 0.015) in patients with a higher antibody level. By using the previously recommended titre of 1:640 as a cut-off point for active infection, all significant differences were lost. Of 12 patients with positive stool culture, 7 had a titre value of at least 1:1280, suggesting a sensitivity of 58%. However, of 20 patients with negative culture, 4 showed this titre value, three of whom were studied several weeks after the onset of their illness. In those patients with clinically proven Campylobacter infection, the antibody response was characterized by a rapid initial rise and a slow four-fold drop in antibody titre after 3 to 5 months. Colonic involvement of the infection was seen in 63% of our patients with positive cultures. Our results support the conclusion that ELISA is a valuable method of diagnosing C. jejuni infections when stool cultures are likely to become negative, as is the case in prolonged complaints or complications after gastro-enteritis or in proctocolitis or after the use of antibiotics. Serial serum samples have no advantage over a single sample for antibody detection.(ABSTRACT TRUNCATED AT 250 WORDS)