**Abstract**

Acute appendicitis is the most common surgical disease presented in ED. Ongoing evidence in the literature, in the last 20 years, shows a lot of benefits in favor of conservative treatment. Despite that conservative treatment does not gain the correct position at the daily practice up to day. A large number of parameters related to acute appendicitis, present diversity in their appearance, so the final estimation of the disease may by unclear and the decision for treatment may be incorrect. We analyze these parameters, aiming to clarify their role in correct diagnosis and decision making on appropriate treatment. In the present study a review of the literature is performed, regarding the etiology, pathology, clinical presentation, laboratory, and imaging data of acute appendicitis. The collection and correct estimation of these parameters, is the key for the correct diagnosis of acute appendicitis. Complicated or uncomplicated cases should be diagnosed preoperatively. The next step is the appropriate treatment, conservative or by surgery. At the present time, excluding generalized peritonitis and sepsis, the majority of patients with uncomplicated acute appendicitis and selected complicated cases can by treated successfully by conservative treatment. The majority of patients do not benefit from appendectomy.

**Keywords:** acute appendicitis, conservative treatment, decision making, laboratory, radiology, peritonitis, appendectomy, complicated, uncomplicated

#### **1. Introduction**

According to the literature of the last 20 yrs., the majority of patients with acute appendicitis should be treated conservatively and not by surgery, as they do not benefit from appendectomy and the operation is considered unnecessary. Unfortunately, worldwide surgical treatment of acute appendicitis remain the gold standard treatment of choice; in a recent multi-centric study in 2018 [1], based in a large number of patients with acute appendicitis, more than 95% of patients were treated by surgery, while conservative treatment underwent less than 5% of the patients. Taking into account the recent literature, the percentages for correct treatment, should be: 80–95% conservative treatment and 5–15% surgical treatment.

At the present study we review and analyze the role of many parameters, influencing the clinical presentation of the patient, the correct diagnosis and decision making for the proper treatment. The role of etiology, pathology and anatomy of acute appendicitis is analyzed. In addition the role of predictive markers/factors, inflammatory markers and radiological data, linked with diagnosis-evolution and severity of acute appendicitis is discussed. Emphasis is given in clinical presentation of the patient and the decision making for conservative or surgical treatment.
