Observation of Initial Procalcitonin and the Clinical Course of Patients With Acute Respiratory Tract Infections

Primary endpoint:

• initial Procalcitonin values of patients with Acute Respiratory Tract Infections

Secondary endpoints:

• correlation of initial Procalcitonin values to classify Acute Respiratory Tract Infections
• correlation of initial Procalcitonin values to subjective severity of Acute Respiratory Tract Infections
• correlation of initial Procalcitonin values to antibiotic- prescriptions
• correlation of initial Procalcitonin values to frequency of admission to hospital
• correlation of initial Procalcitonin values to frequency of referrals (radiology, pneumology)

Inclusion criteria

• written informed consent
• all types of respiratory tract infection according to investigator´s diagnosis

Exclusion criteria

• pretreatment with antibiotics in the past 2 weeks
• portal hypertension
• Major surgeries or multiple trauma which require hospitalization, in previous 4 weeks
• Autoimmune disease and systemic diseases (lupus erythematodes, wegener´s disease)
• Peritoneal dialysis
• Acute treated or recently operated medullary c-cell-carcinoma, SCLC, carcinoid
• Other inflammatory diseases (e.g. urinary tract infection, pyelonephritis, pancreatitis