The following criteria apply to IRIS in WD: 1) an initial clinical response of symptoms to antimicrobial treatment (cessation of diarrhea and fever, relief of arthritis, and normalization of the C-reactive protein level) within 3 weeks of treatment; 2) recurrence of systemic or local inflammation, with or without fever, lasting more than 1 week, after exclusion of hospital-related conditions; and 3) exclusion of WD recurrence based on histological examination and a negative PCR result for T. whipplei despite IRIS manifestation. Here, CRP is linked to Arthritis.