Acalculous cholecystitis is a type of inflammation of the gallbladder. This small, pear-shaped organ stores bile, a fat-digesting liquid made by the liver.
When too much cholesterol or bilirubin (a waste product from red blood cells) gets into the bile, pebble-like deposits called gallstones can form, resulting in the inflammatory disease calculus cholecystitis.
Acalculous cholecystitis, in which the gallbladder is inflamed without the presence of gallstones, is much rarer, accounting for only 5 to 10 percent of cholecystitis cases. It is also usually more serious — and potentially even life-threatening.
“The signs and symptoms of acalculous cholecystitis are similar to calculous cholecystitis,” says Felipe Boff Maegawa, MD, a surgeon at Emory Healthcare in Atlanta who specializes in procedures related to the liver, bile ducts, gallbladder, and pancreas.
If the patient experiences sharp pain when pressed deeply in the right side of the abdomen, that is called a positive Murphy sign, which is considered a hallmark of cholecystitis. This pain may come on suddenly and radiate to the shoulder and back. It also may occur when breathing in deeply.
Other symptoms include:
Nausea and vomiting
Fever
Upper abdominal pain
Food intolerances, bloating, and belching
In many cases, patients with acalculous cholecystitis have been in the hospital for other significant illnesses or are recovering from major surgery.
“Patients who are very sick [with acalculous cholecystitis] can also be ‘septic,’” where they have dangerously low blood pressure due to infection,” says David Diehl, MD, a gastroenterologist and clinical professor of medicine and pathology at Geisinger Commonwealth School of Medicine in Danville, Pennsylvania.
Although the cause of acalculous cholecystitis is not entirely known, it is associated with trauma, burns, and complications from surgery, particularly in critically ill patients or those recuperating from major operations.
Some surgeries can disrupt normal blood flow to the gallbladder, causing ischemia (a reduction in blood supply). A major operation may also introduce bacteria into the bloodstream and increase the risk of a gallbladder infection.
In addition, surgery can reduce the gallbladder’s ability to empty bile as it should, and this buildup can further impair blood flow, damage tissue, and aggravate inflammation.
Dr. Maegawa lists the following as factors that may raise the risk of getting acalculous cholecystitis:
Major surgery
Trauma
Burns
Sepsis caused by bacterial, fungal, viral, or parasitic infections
Critical illness requiring intensive care
Total parenteral nutrition (TPN), in which nutrients are provided directly into the bloodstream through an IV
Prolonged fasting, which along with TPN can create a slowing of fluids in the gallbladder and negatively effect the composition of bile
Immunodeficiency (in HIV and transplant patients, for example)
“Diagnosis is usually difficult because the critically ill patients are not able to cooperate, as they are sedated, intubated, and unconscious,” says Maegawa.
The diagnostic process might involve:
A clinical evaluation of a patient’s symptoms, followed by a blood test to see if there is an elevated white blood count or another indication of abnormal liver function
Imaging via ultrasound (or possibly X-ray or computed tomography scan) to see if there is a thickening of the gallbladder walls or other signs of inflammation
A detailed specialized scan, such as a HIDA (hepatobiliary iminodiacetic acid) scan, to check for abnormal movements (contractions) of the gallbladder and blocked bile ducts
PTC (percutaneous transhepatic cholangiography), a test that involves injecting a dye into the bile ducts so images may be more clearly viewed on X-rays
ERCP (endoscopic retrograde cholangiopancreatography), which uses X-rays and a long, flexible tube (endoscope) with a light and camera at one end to provide a view of the bile ducts
MRCP (magnetic resonance cholangiopancreatography), which offers detailed imaging of the liver, pancreas, gallbladder, and bile drainage area
There are a number of different approaches for recovering from acalculous cholecystis. Note that most treatments also involve limiting food, since digestion can slow healing.
Medication Options
Antibiotics: Dr. Diehl calls antibiotics “the cornerstone of therapy.” They are often administered intravenously.
Fluids and pain medications: These can ease symptoms and help with healing.
Surgery and Procedures
Percutaneous cholecystostomy: The insertion of a drainage tube relieves pressure and helps clear infection.
Cholecystectomy: In some cases, a surgeon will remove the gallbladder. Diehl stresses that doctors typically try to avoid this because patients with acalculous cholecystitis usually also have another severe medical condition that makes surgery risky. Under normal conditions, gallbladder removal is considered a safe procedure; the body adjusts as bile simply flows directly into the small intestine from the liver.
To help lower the chances of developing acalculous cholecystitis, Maegawa notes the importance of a healthy, active lifestyle and the importance of closely managing any chronic conditions you may have.
“Conditions such as diabetes, hypertension, atherosclerosis, obesity, and HIV can increase the risk of the development of acalculous cholecystitis in the event of critical illness,” he says.
It’s worth noting that the following conditions increase the incidence of acalculous cholecystitis, so taking any possible steps to avoid them could be beneficial:
Long periods of fasting
Total parenteral nutrition
Drastic weight loss
Acalculous cholecystitis is considered a potentially lethal disease. The number of patients who die from it ranges from 12 to 65 percent, depending on the severity of the underlying illness and the speed of diagnosis and treatment.
Even those who survive have a long recovery that can take months.
If not treated promptly, the disease can lead to:
Death of gallbladder tissue (gangrenous cholecystitis): This can cause a severe infection that could spread throughout the body.
Gallbladder splitting open (perforated gallbladder): This also can spread the infection within your gut or lead to a buildup of pus (abscess).
Emergency surgery to remove the gallbladder is needed to treat these complications in about 2 or 3 in every 10 cases.
Acalculous cholecystitis accounts for 10 percent of all cases of acute (sudden) cholecystitis and 5 to 10 percent of all cases of cholecystitis (gallbladder inflammation).
The disease has an incidence rate of 0.12 percent in the entire population.
Eight out of 10 cases of acalculous cholecystitis are in male patients, and most of those are ages 50 and older.
Research suggests that racial and ethnic minorities (especially males) and people of lower socioeconomic status may be more likely to undergo percutaneous cholecystostomy (insertion of a drainage tube) instead of cholecystectomy (removal of the gallbladder), even when cholecystectomy is the preferred treatment.
Acalculous cholecystitis is often related to other medical conditions, particularly those affecting the gallbladder or those that cause systemic inflammation or decreased blood flow to the gallbladder.
These conditions include:
Systemic infections
Critical illnesses
Major trauma or surgery
Prolonged fasting
Liver diseases
Diabetes
Immunocompromised states
Certain cancers
Acalculous cholecystitis is a rare and life-threatening type of gallbladder infection that does not involve the presence of gallstones.
The disease can develop in patients who have other significant illnesses or are recovering from major surgery.
Acalculous cholecystitis can be difficult to diagnose, but the sooner it is identified and treated, the better the odds are of survival.
