The diagnosis of pneumonia-induced thyrotoxicosis can be challenging as symptoms may mimic other conditions and laboratory testing may not always provide a clear answer. The diagnosis is confirmed with low thyroid-stimulating hormone (TSH) and elevated free thyroxine (T4) and triiodothyronine (T3), erythrocyte sedimentation rate (ESR), and C-reactive protein. This evidence concerns the gene CRP and pneumonia.