Acalculous cholecystitis is an inflammatory disease of the gallbladder without evidence of gallstones or cystic duct obstruction[1, 2] ; it is a severe illness that is a complication of various other medical or surgical conditions. Duncan first recognized it in 1844 when a fatal case of acalculous cholecystitis complicating an incarcerated hernia was reported. The condition causes approximately 5%-10% of all cases of acute cholecystitis and is usually associated with more serious morbidity and higher mortality rates than calculous cholecystitis. It is most commonly observed in the setting of very ill patients (eg, on mechanical ventilation, with sepsis or severe burn injuries,[3] after severe trauma[4] ). In addition, acalculous cholecystitis is associated with a higher incidence of gangrene and perforation compared to calculous disease.
The usual finding on imaging studies is a distended acalculous gallbladder with thickened walls (>3-4 mm) with or without pericholecystic fluid. Acalculous cholecystitis can be observed in patients with human immunodeficiency virus (HIV) infection, although it is a late manifestation of this disease. Acalculous cholecystitis can also be found in patients on total parenteral nutrition (TPN), typically those on TPN for more than three months.
The main cause of this illness is thought to be bile stasis and increased lithogenicity of bile. Critically ill patients are more predisposed because of increased bile viscosity due to fever and dehydration and because of prolonged absence of oral feeding resulting in a decrease or absence of cholecystokinin-induced gallbladder contraction. Gallbladder wall ischemia that occurs because of a low-flow state due to fever, dehydration, or heart failure may also play a role in the pathogenesis of acalculous cholecystitis.
The main cause of acalculous cholecystitis is gallbladder stasis with resulting stagnant bile. This is observed most commonly in patients with sepsis, patients in intensive care units, patients on long-term total parenteral nutrition (TPN), those with cardiovascular disease,[2] patients with diabetes (occasionally), or other patients with gallbladder dysmotility. The condition has been reported during pregnancy, as a complication of hepatitis A.[5] It has been rarely reported in children, also as a complication of hepatitis A,[6] with a favorable course with conservative treatment. This disease has also been reported as associated with aortic dissection.[7]
Acalculous cholecystitis comprises approximately 5-10% of all cases of acute cholecystitis.
It can occur in all races.
Acalculous cholecystitis has a slight male predominance, unlike calculous cholecystitis, which has a female predominance.
The condition can occur in persons of any age, although a higher frequency is reported in persons in their fourth and eighth decades of life.
The prognosis of patients with acalculous cholecystitis is guarded.
The mortality and morbidity rates associated with acalculous cholecystitis can be high; the illness is frequently observed in patients with sepsis or other serious conditions. The reported mortality range is 10%-50% for acalculous cholecystitis as compared to 1% for calculous cholecystitis.
A study by Gu et al found a significantly higher frequency of cerebrovascular accidents in patients with acute acalculous cholecystitis (AAC) than those with acute calculous cholecystitis (ACC), the respective rates being 15.9% and 6.7%. The incidence of gangrenous cholecystitis was also greater in the AAC than in ACC (31.2% vs 5.6%, respectively).[8]
Perforation or gangrene of the gallbladder and extrabiliary abscess formation may occur.[9]
History findings are of limited value. Often, many patients are very ill (possibly on mechanical ventilation) and cannot communicate a history or symptoms. Physical examination may reveal fever and right upper quadrant tenderness.
It is crucial that clinicans rapidly identify cases of acute acalculous cholecystitis to avoid a delay in treatment and consequent clinical deterioration of affected patients.[2]
A complete blood cell (CBC) count, liver function studies, and blood culture tests are some of the main laboratory tests that should be performed. However, note that laboratory findings may be negative or inconclusive in late-stage disease,[2] and bile culture results are negative in nearly 50% of patients with acalculous cholecystitis, probably because of concurrent antibiotic therapy in these patients.
Perform abdominal ultrasonography[2] or computed tomography (CT) scanning.
For surgical candidates, perform cholecystectomy using an open or laparoscopic approach as indicated. For patients who are not surgical candidates, perform percutaneous cholecystostomy.[10, 11, 12, 13]
When the diagnosis of acalculous cholecystitis is established, immediate intervention is indicated because of the high risk of rapid deterioration and gallbladder perforation.
In patients with acalculous cholecystitis who are high-risk surgical candidates (ie, end-stage liver disease), Gu et al reported that endoscopic gallbladder stent placement as an effective palliative treatment.[8] This involves placement of a double pigtail stent between the gallbladder and the duodenum during endoscopic retrograde cholangiopancreatography (ERCP). However, the definitive treatment of acalculous cholecystitis is cholecystectomy for patients who are able to tolerate surgery.
In selected patients with acute acalculous cholecystitis (AAC), nonsurgical treatment (such as antibiotics or percutaneous cholecystostomy) may be an effective alternative to surgery.[8, 14] In the study by Gu et al, data from 69 patients with AAC was compared with those from 415 patients with acute calculous cholecystitis (ACC). The investigators found that among those patients who underwent nonsurgical therapy, the posttreatment recurrence rate was just 2.7% in the AAC group, compared with 23.2% in the ACC patients.[8]
In a retrospective study of 15 nonsurgical patients who underwent endoscopic ultrasonography-guided transmural gallbladder drainage (EUS-GBD) with a lumen-apposing metal stent (LAMS) for different biliary conditions including four cases of acalculous cholecystitis, technical success was achieved in 14 of the 15 patients (93%), with clinical success in all 15 patients (median follow-up, 160 days).[15]
Consult with the following specialists:
Patients in the acute stage of acalculous cholecystitis should receive nothing by mouth. Hydration with intravenous fluids should be provided.
In surgical candidates, open or laparoscopic cholecystectomy is indicated for acute cholecystitis.[1, 16] Laparoscopic cholecystectomy performed within 24 hours of inpatient admission has been reported to be safe and is recommended as the preferred treatment option for those with American Society of Anesthesiologists (ASA) grade I-III disease.[17]
In patients who are not surgical candidates, percutaneous cholecystostomy may be performed in the radiology suite. This procedure may the safest and most successful intervention in patients who are critically ill, have multiple comorbidities, have a high risk for conversion, or who are poor surgical candidates.[1] Catheters are usually removed after approximately three weeks in critically ill patients with acalculous cholecystitis who have undergone percutaneous cholecystostomy. This allows for the development of a mature track from the skin to the gallbladder.
In an observational study (2002-2012) of 56 patients treated with percutaneous cholecystostomy for acute acalculous cholecystitis, Kirkegard et al found the procedure could be used as a definitive treatment option in 45 patients (80.4%) and as a bridge to elective laparoscopic cholecystectomy in 4 patients (7.1%) within a median of 8.8 months.[14] Six patients (10.7%) died within the 30-day postprocedure period.
Anderson et al reported that cholecystostomy offered no survival benefit for patients with severe sepsis and shock; however, cholecystostomy was associated with improved survival compared with patients without surgical management.[18]
Administer broad-spectrum antibiotics for enteric and biliary pathogen coverage. Definitive treatment is cholecystectomy in patients who are surgical candidates or cholecystostomy in patients who are not surgical candidates.