A 63-year-old man, who was a glass craftsman and a sewer cleaner, on haemodialysis for 19 years due to autosomal dominant polycystic kidney disease (ADPKD), was referred by his family doctor for suspicion of renal cyst infection after presenting with a persistent fever of approximately 38 °C, right lumbar back pain, and elevated C-reactive protein (CRP) levels for the past 14 days. The gene discussed is CRP; the disease is autosomal dominant polycystic kidney disease.