AN ASSOCIATION OF MEMBRANE-DAMAGING TOXINS FROM COAGULASE-NEGATIVE STAPHYLOCOCCI AND CHRONIC OROFACIAL MUSCLE PAIN

Forty-six patients presenting with chronic orofacial muscle pain and e ight age- and sex-matched control subjects were investigated for the c arriage prevalence of, and exotoxin production by, coagulase-negative staphylococci (CNS), The eight control subjects were selected from an initial group of 41 subjects on the basis of the absence of musculoske letal symptoms. There was a significantly higher prevalence and multip le carriage of four or more strains of CNS in patients with chronic mu scle pain than in control subjects (23 versus 9 isolates/10 subjects). Two of the 103 CNS isolates from patients with muscle pain and none f rom the control subjects produced toxic shock syndrome toxin 1 (TSST-1 ), suggesting that pyrogenic toxins do not significantly contribute to the aetiology of chronic muscle pain. There was a significantly highe r prevalence of delta-haemolysin (41 of 114) and 'horse'-haemolysin (5 6 of 114) production by CNS isolates from patients with chronic muscle pain compared with those from control subjects. None of the control s ubjects was colonised with CNS that produced significant amount of eit her delta- or 'horse'-haemolysin, whereas 35 of 44 patients with chron ic orofacial muscle pain were colonised with CNS that produced signifi cant amounts of 'horse'-haemolysin, 37 that produced delta-haemolysin and 33 that produced both delta- and horse-haemolysin, This study sugg ests that membrane-damaging toxins, like delta- and 'horse'-haemolysin , may play a role in the aetiology of chronic orofacial muscle pain.