Acute acalculous cholecystitis (AAC) is an acute inflammatory disorder of the gallbladder, which can complicate the recovery of burn patients. No formal literature review has been performed about this uncommon but potentially fatal complication in burn care. A Pubmed search from 1950 to 2015 was performed using MESH terms: "acalculous cholecystitis," "burns or thermal injuries or thermal damage," and "cholecystitis or gallbladder inflammation." The articles were analyzed and data collected individually on the incidence, presenting symptoms or signs, risk factors, investigations, and treatment modalities used. An International Burns Injury Database (IBID) search was additionally performed to identify the incidence of AAC in burn patients between 2005 and 2015 in the United Kingdom. Nineteen articles were identified which described 90 cases of AAC and thermal injuries. The incidence of AAC in burns ranges between 0.4 and 3.5%, typically affecting males (82.4%) with a mean age of 35 (range 13-89), and 97.8% of burns were >30% total body surface area (range: 22-80%). The majority of patients had established known risk factors for acquiring AAC, including blood transfusion (56.6% of patients), sepsis (52.2%), mechanical ventilation (45.5%), prolonged fasting or total parenteral nutrition administration (44.4%), and use of narcotic medication (10%). The IBID search identified one case of AAC among 145,227 burn injuries during 2005 to 2015 in the United Kingdom. AAC is a rare life-threatening condition that is associated with large thermal burns. Improvements in burns critical care have probably improved the management of known risk factors and reduced the incidence of this condition over recent decades.

Infectious mononucleosis is a common disease of the adolescent caused by the Epstein-Barr virus (EBV). We present a rare case of a male adult with acalculous cholecystitis due to infectious mononucleosis. A correct diagnosis was challenging due to a false negative antibody test. Laboratory values were significant for a marked lymphocytosis and an early Immunoglobulin G (IgG) response without initial Immunoglobulin M (IgM) elevation. However, IgM antibodies were elevated two weeks later. Symptoms resolved quickly under symptomatic therapy. Antibody level patterns in asplenic patients with infectious mononucleosis are characterized by an atypical course with a delayed rise in IgM antibodies, which complicates the correct diagnosis of an EBV-induced acalculous cholecystitis.

Acute acalculous cholecystitis (AAC) is most commonly seen after surgery in critically ill patients. Early diagnosis and treatment is the key in the management of AAC. Ultrasound is the commonly used first modality for right upper quadrant (RUQ) pain with sensitivity equal to or greater than 80% for AAC. Computed tomography (CT) scan is reported to have a sensitivity close to 90% and if both the ultrasound and CT scan are combined, it further increases the sensitivity for the diagnosis of AAC. It is unlikely for AAC to be present in the setting of both negative ultrasound and CT scan of the abdomen. Our case report presents a similar clinical scenario where the patient was found to have both negative ultrasound and CT scan abdomen but was positive on hepatobiliary iminodiacetic acid (HIDA) scan for AAC as stated below. A 32-year-old male presented to the emergency room with complaints of RUQ pain for two days which was associated with one episode of non-bilious and non-bloody vomiting as well as subjective fever and chills. On presentation, the patient's blood pressure was 87/54 mmHg. Other vitals were unremarkable. The patient had both CT scan abdomen and ultrasound of the RUQ done which reported non-specific findings but were grossly negative for AAC. On the first night of admission, the patient's blood pressure dropped to 84/32 mmHg. The patient was transferred to the intensive care unit (ICU) given the concern for sepsis and was started on intravenous (IV) vancomycin, IV metronidazole and IV levofloxacin (patient was allergic to penicillin). Given the high clinical suspicion, a HIDA scan performed which was positive for AAC. The patient then had a cholecystostomy tube placed by the interventional radiology team. The patient improved rapidly and was eventually discharged with a 14-day course of Bactrim DS (Roche Pharmaceuticals, Nutley, NJ) and metronidazole, and four weeks of outpatient follow up with general surgery. The patient underwent outpatient cholecystectomy in the eighth week from discharge. This leads to the conclusion that even if both the ultrasound and CT scan of the abdomen are negative and clinical suspicion is still high for AAC, the patient should undergo a HIDA scan as delay in treatment is associated with greater than 50% mortality in patients with AAC.

We present the case of a young female with symptoms of biliary colic and a biochemical profile consistent with biliary obstruction. Imaging was suspicious for Mirizzi's syndrome. Intraoperatively, the patient was found to have a complete intrahepatic gallbladder causing common hepatic duct compression with final pathology confirming acute cholecystitis. We review the embryological development of the gallbladder as well as clinical presentation of Mirizzi's syndrome. Special consideration for clinical workup and surgical management is discussed.