Some serological markers were measured in all patients, such as procalcitonin (PCT), D- dimer, tumor necrosis factor-α (TNF-a), C-reaction protein (CRP), interleukin-6 (IL-6), etc. There was no distinction in age, gender, BMI, heart rate, blood pressure, body temperature, hypertension, diabetes mellitus, coronary artery disease, and bronchitis among CAP patients in three groups. Here, TNF is linked to bronchitis.