The study aims to assess and analyze some selected antioxidants and laboratory parameters during hospitalization of the patients with acute pancreatitis. It will allow to better understanding of the mechanisms of disease and the development of better diagnostic, treatment and monitoring.

It is an observational diagnostic study and does not involve any additional administration of medicinal substances, modification of treatment or dropping the use of routine methods of treatment of a disease. The study procedure includes detailed personal medical history as separate document like as a routine medical interview, and three times taking a small amount of venous blood (together about 15 ml), in the first, third, and seventh day of hospitalization (in the case of longer hospital treatment).

Inclusion Criteria:

• The patients were classified into the group of patients with acute pancreatitis (AP) due to clinical symptoms (acute onset of a persistent, severe, epigastric pain with tenderness on palpation on physical examination), personal interview and clinical method used in the diagnosis of pancreatitis - laboratory tests (elevation in serum lipase or amylase to three times or greater than the upper limit of normal) and characteristic findings of acute pancreatitis on imaging (contrast-enhanced computed tomography (CT), magnetic resonance imaging (MRI) or transabdominal ultrasonography). In patients with characteristic abdominal pain and elevation in serum lipase or amylase to three times or greater than the upper limit of normal, no imaging was required to establish the diagnosis of acute pancreatitis. In patients with abdominal pain that was not characteristic for acute pancreatitis or serum amylase or lipase levels that were less than three times the upper limit of normal, or in whom the diagnosis was uncertain, the investigators performed abdominal imaging with a contrast-enhanced abdominal CT scan to establish the diagnosis of acute pancreatitis and to exclude other causes of acute abdominal pain. In patients with severe contrast allergy or renal failure, the investigators performed an abdominal MRI without gadolinium.
• The volunteers classified as healthy based on the research conducted by clinicians of primary medical care (control group)

Exclusion Criteria:

• other accompanied diseases than acute pancreatitis (the patients groups)
• Individuals of the control group with diagnosed disease as well as alcohol and drugs abusers

1. The healthy volunteers classified as a control group based on the research conducted by clinicians of primary medical care, divided on smokers and non-smokers.
2. The patients classified into the group of patients with acute pancreatitis, divided on smokers and non-smokers.