Cholecystitis is inflammation of the gallbladder, a small organ located beneath the liver that stores bile to aid in fat digestion. It most commonly occurs due to obstruction of the cystic duct by gallstones, leading to bile accumulation and inflammation. The condition may be acute or chronic.   Causes The most common causes include: • Gallstones (accounting for over 90% of cases) • Bacterial infection • Tumors obstructing bile flow • Prolonged fasting or rapid weight loss • Severe illness (acalculous cholecystitis) Types 1. Acute Cholecystitis: Sudden onset with severe right upper quadrant pain. 2. Chronic Cholecystitis: Repeated inflammation leading to thickened gallbladder wall and fibrosis.     Symptoms • Severe right upper abdominal pain (may radiate to right shoulder) • Nausea and vomiting • Fever • Abdominal bloating • Pain worsening after fatty meals   Risk Factors • Female gender • Obesity • Pregnancy • Diabetes • Hyperlipidemia • Age over 40   Complications • Gallbladder rupture • Abscess formation • Peritonitis • Sepsis   Diagnosis • Physical examination (Murphy’s sign) • Blood tests (elevated WBC) • Ultrasound (first-line imaging) • CT or MRI if needed   Treatment Conservative management: • Fasting • IV fluids • Antibiotics • Pain control     Surgical treatment: • Laparoscopic cholecystectomy (definitive treatment)   Prevention • Maintain healthy body weight • Reduce saturated fat intake • Avoid rapid weight loss • Regular physical activity Roaa Nashat Al-Mustaqbal University The First University in Iraq.