In the laboratory parameters, we observed a significant elevation of CRP as well as an elevation of other pro-inflammatory cytokines like serum amyloid A, interleukin-6 and alpha-1 acid glycoprotein during the attacks compared to the attack-free periods, and also a slight elevation of procalcitonin (possible coincidence of PFAPA attack and bacterial superinfection) in some patients. Here, CRP is linked to PFAPA syndrome.