Alice Lawson, a 47-year-old woman brought to the ED by her husband, is complaining of severe right upper quadrant (RUQ) abdominal pain, which she describes as radiating to her right shoulder. It began suddenly the day before, shortly after she returned from a picnic, and since then Ms. Lawson, who is short and heavyset, has had no appetite, has had fever and nausea, and vomited twice today. Lying immobile on her side on the stretcher, she begs you not to move her, because movement intensifies the pain.
Her vital signs are: blood pressure, 135/72 mmHg; pulse, 104 beats per minute; respiration, 22 breaths per minute; and temperature, 101.2[degrees]F. Her skin is warm and dry, her sclera mildly icteric. A physical examination is remarkable for a distended abdomen with decreased bowel sounds in four quadrants. The RUQ is markedly tender to palpation and Murphy sign-the abrupt cessation of inspiration because of pain when the RUQ is palpated-is present on deep palpation. A smooth liver edge can be palpated, but the gallbladder is not palpable. Abdominal guarding is noted.
WHAT ARE THE CLUES?
You suspect that Ms. Lawson has acute cholecystitis. Patients with this condition complain of sudden-onset, severe, and ongoing pain in the RUQ or epigastric region of the abdomen. Rebound tenderness and guarding are often present. Referred pain-pain that is felt in a superficial area distant from the actual deep structure from which it originates-may be experienced in the right scapula, mid-back, or right shoulder, and is attributed to innervation of both the superficial and deep areas by the same spinal segment.
Pain intensity often increases with movement or respirations, and a positive Murphy sign strengthens support of the diagnosis. Severity of pain is variable; older patients, those with diabetes mellitus, and those receiving corticosteroid therapy may report minimal or no pain. In approximately 15% of cases, the distended gallbladder is palpable.
Anorexia, nausea, and vomiting are usually present, and patients may have low-grade fever. The presence of high fever and chills may indicate septic complications. In the elderly, fever may be the only clinical sign of acute cholecystitis. In contrast, immunocompromised patients may not be able to mount febrile responses. An acute attack is often precipitated by large, fatty meals.
Finally, mild jaundice, which is more apparent in fair-skinned patients, may be observed in those experiencing acute cholecystitis. This is attributable to edema of the common bile duct, which causes bilirubin to diffuse across the inflamed gallbladder mucosa.
TAKING ACTION
You initiate an IV running normal saline at 125 cc/hour. You send blood for a complete blood count (including differential), total bilirubin, serum aspartate aminotransferase (AST), serum alanine aminotransferase (ALT), alkaline phosphatase (ALP), and amylase levels. A surgical consultant is called.
The results of the blood tests support the diagnosis of acute cholecystitis; leukocytosis is present, with a white blood cell count of 13,500/[mu]L; the total bilirubin level is elevated at 3.0 mg/dL, indicating possible biliary tree obstruction; an elevated ALP level of 145 U/L suggests extrahepatic biliary obstruction; the AST and ALT levels are also elevated at 68 U/L and 55 U/L, respectively. These findings are most likely secondary to cholestasis and cholecystitis. A slightly elevated amylase level of 140 IU/L may reflect common bile duct obstruction and is a typical finding in the patient with acute cholecystitis. A serum amylase level higher than 500 IU/L, however, strongly suggests pancreatitis.
After examining the patient, the surgeon concurs with your diagnosis of acute cholecystitis. He orders 4 mg IV of morphine. Supine and upright abdominal films show no evidence of gallstones, but this is not surprising, as gallstones are radiopaque in only 10% to 15% of cases. An RUQ abdominal ultrasound scan does, however, reveal gallstones, but this doesn't confirm the diagnosis.
A hepatobiliary scan is ordered. Ms. Lawson receives an IV injection of a technetium-99m-labeled dimethyl iminodiacetic acid derivative, which is then followed by scanning with a gamma camera. This diagnostic test permits visualization of the hepatobiliary tract, but Ms. Lawson's gallbladder cannot be visualized as a result of obstruction of the cystic duct, a hallmark of cholecystitis.
PRIMER ON CHOLECYSTITIS
Acute cholecystitis is the result of cystic duct obstruction by gallstones or biliary sludge. Cholecystitis is the most common complication of gallstone disease and most patients suffering from it have a history of biliary colic. The incidence of gallstone disease increases with age and the chief risk factors for it include female gender, obesity, and metabolic dysfunctions such as diabetes mellitus or hyperlipidemia (also known as the four Fs: Female, Forties, Fat, and Fertile).
Acalculous cholecystitis (cholecystitis without gallstones) is a severe illness that may occur in the elderly or in patients with trauma, extensive burns, or recent surgery. It is also associated with prolonged immobility and fasting, prolonged use of total parenteral nutrition, diabetes mellitus, vasculitis, and torsion of the gallbladder. Parasitic infestation of the gallbladder also can cause acalculous cholecystitis. The pathophysiology of acalculous cholecystitis is unclear but it may relate, in part, to biliary stasis due to fasting.
In acute cholecystitis, ductal obstruction is soon followed by chemical inflammation and superimposed infection of the gallbladder. Initially, bile may be sterile, but tissue necrosis, stasis of bile, and blockage of lymphatic drainage may later cause bacterial growth. Empyema, gangrene, or perforation can occur.
ADMISSION
Ms. Lawson will be admitted to the medical unit. She is assigned NPO status and provided with continuous IV hydration.
Antibiotics are generally withheld in straightforward, uncomplicated cases of acute cholecystitis, but they are ordered in cases of acute peritonitis or sepsis.
Acute cholecystitis is managed either medically or surgically, but surgical intervention is the treatment of choice. Medical management may be chosen for elderly patients, patients with diabetes mellitus, or patients who are poor surgical candidates, who afterward are observed closely for recurrent symptoms, gangrene of the gallbladder, or cholangitis.
Surgical cholecystectomy is performed by either laparoscopy or laparotomy. If common bile duct obstruction is suspected, then an endoscopic retrograde cholangiograpy with sphincterotomy may be performed to explore the duct prior to laparoscopy. If laparotomy is performed, the common bile duct is explored and cleared of gallstones at the time of the procedure. A T-tube drain may be inserted at that time to ensure patency of the duct and, in addition, a drainage tube may be placed in the gallbladder bed to further aid fluid drainage.
Laparoscopic cholecystectomy has become more common in cases of uncomplicated acute cholecystitis. It's associated with a shorter postoperative length of stay, faster recovery, lower rate of morbidity, and a lower mortality rate than is an open procedure. Conversion to an open procedure is more frequent when laparoscopy is performed for acute cholecystitis than for biliary colic due to gallstones.
Controversy exists in regard to the timing of the surgery. Immediate cholecystectomy is performed if peritonitis is suspected. Often, if peritonitis is not suspected, the surgery will be performed two or three days after hospitalization, after the acute episode has begun to resolve with conservative treatment (for example, analgesia, hydration, NPO status, antibiotics). In some cases, such as those in which the patient is a poor surgical candidate, surgery may be scheduled electively approximately six weeks after the onset of the acute episode. However, delaying surgery risks the recurrence of acute cholecystitis or the development of pericholecystic fibrosis and will make it more difficult. Critically ill patients who can't tolerate a full surgical procedure are managed more conservatively through placement of a drainage tube in the gallbladder. The decision regarding surgical intervention is then made when the patient's condition improves.
FOLLOW-UP
Ms. Lawson undergoes cholecystectomy by laparotomy during her hospitalization. Exploration of the common bile duct reveals obstruction by gallstones and a T-tube is inserted by the surgeon. Following an uneventful postoperative recovery, she is discharged after three days.
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