Although an elevation in CRP levels in patients with AC may be related to an infection-associated change or a non-specific change, an interaction between the hypothalamus-pituitary-adrenal (HPA) axis and proinflammatory cytokines such as interleukin-1, interleukin-6, and tumour necrosis factor-α is a well-known feature of AC11. The gene discussed is CRP; the disease is infection.