Doctoral Thesis / Dissertation from the year 2018 in the subject Medicine - Diagnostics, grade: 10, Ss. Cyril and Methodius University of Skopje (Medical faculty), language: English, abstract: This study aims to establish the role of hyperbilirubinemia as a laboratory marker in prediction of acute appendicitis in the early diagnosis and complicated appendicitis, as well as to compare laboratory markers such is C - reactive protein, Aspartate Aminotransferase (AST), Alanine Aminotransferase (ALT) and WBC together with Alvarado scoring model. Even though appendicitis has been known since two centuries ago, acute appendicitis presents a diagnostic challenge for the majority of general surgeons during their work, regardless of several diagnostic modalities applied. This is a cross-sectional study, conducted in the University Clinical Center of Prishtina in the Department of Abdominal Surgery and in General Hospital of Mitrovica. The prospective data collection included 201 patients admitted in the emergency ward with suspicion for acute appendicitis, in which the preoperative diagnosis of acute appendicitis was established and appendectomy was performed, during the period from September 2016 up to October 2017.