Gallstone Disease: Common Questions and Answers.

In the United States, 10% to 15% of adults are affected by gallstones, and cholesterol gallstones are the most prevalent subtype. Risk factors for developing gallstone disease include female sex; older age; certain medications; and having type 2 diabetes mellitus, nonalcoholic fatty liver disease, obesity, rapid weight loss, or hemolytic anemia. Nearly 80% of gallstones are found incidentally and remain asymptomatic. When symptomatic, gallstone disease usually presents as sudden onset right upper quadrant or epigastric abdominal pain. Common complications of gallstones include cholecystitis, choledocholithiasis, gallstone pancreatitis, and ascending cholangitis. The Murphy sign is a specific physical examination finding for acute cholecystitis. Ultrasonography is the initial imaging choice for detecting gallstones and acute cholecystitis. A hepatobiliary iminodiacetic acid (HIDA) scan can be used to evaluate for cholecystitis in patients with negative or equivocal ultrasound findings. Magnetic resonance cholangiopancreatography (MRCP) is an accurate, noninvasive diagnostic test to identify choledocholithiasis, certain malignancies, and biliary obstruction. Nonsteroidal anti-inflammatory drugs are safe and effective in treating pain from acute cholecystitis and biliary colic. Laparoscopic cholecystectomy is the treatment of choice for most patients with biliary colic or acute cholecystitis. Ursodeoxycholic acid and chenodeoxycholic acid should not routinely be used to treat gallstone disease, but they can be used as a nonsurgical alternative for certain patients. Postcholecystectomy syndrome is a potential postoperative complication that presents with abdominal pain, bloating, and diarrhea. (Am Fam Physician. 2024;109(6):518-524.

X-ray crystallographic structure of BshB, the zinc-dependent deacetylase involved in bacillithiol biosynthesis.

Many gram-positive bacteria produce bacillithiol to aid in the maintenance of redox homeostasis and degradation of toxic compounds, including the antibiotic fosfomycin. Bacillithiol is produced via a three-enzyme pathway that includes the action of the zinc-dependent deacetylase BshB. Previous studies identified conserved aspartate and histidine residues within the active site that are involved in metal binding and catalysis, but the enzymatic mechanism is not fully understood. Here we report two X-ray crystallographic structures of BshB from Bacillus subtilis that provide insight into the BshB catalytic mechanism.