Which of the following statements is correct with regard to gastric bypass for obesity?

a. Rapid weight loss following successful gastric bypass for obesity is associated with an increased risk of developing cholelithiasis

The most serious complication after gastric bypass for obesity is anastamotic dehiscence. Leak is presumed to occur secondary to gastric necrosis due to ischemia from staple line application or short gastric vessel ligation. Affected patients may have little pain, with tachycardia, tachypnea and fever as the only manifestations. Physical examination in morbidly obese patients with peritonitis is unreliable. Marginal ulcers occur in only 10% or less of gastric bypass patients and respond to H2 receptor antagonists. Rarely, polyneuropathy has been noted after gastric bypass, usually in association with intractable vomiting and protein calorie malnutrition. Vitamin B12 deficiency has been noted after gastric bypass due to decreased acid digestion of vitamin B12 in food; monthly B12 supplementation should be routine. Cholelithiasis occurs in about one third of morbidly obese patients and gallstone formation is accelerated in the early postoperative period by the effects of rapid weight loss.