A couple seeks counseling about the risk of their child developing a recessive disorder. The woman is affected and upon further testing it is determined that the man is a carrier. Which of the following is true?

Choice A reason: Abdominal pain and rectal bleeding are not the primary signs of a bowel obstruction. Rectal bleeding could be indicative of other gastrointestinal issues such as hemorrhoids, diverticulosis, or colorectal cancer. While abdominal pain is a symptom of bowel obstruction, rectal bleeding is not typically associated with it.

Choice B reason: The primary symptoms of bowel obstruction include abdominal distention, pain, inability to have a bowel movement, and nausea/vomiting. When a bowel obstruction occurs, the normal movement of intestinal contents is blocked, leading to a buildup of contents and gas. This results in abdominal distention and pain. The blockage also prevents the passage of stool and gas, causing constipation or inability to have a bowel movement. Nausea and vomiting are common as the digestive system tries to expel the contents that cannot pass through the obstruction.

Choice C reason: Dehydration, back pain, and fever are not the hallmark symptoms of bowel obstruction. While dehydration can occur due to vomiting and reduced intake, back pain is not commonly associated with bowel obstruction. Fever may indicate an infection or other complications but is not a primary symptom of bowel obstruction.

Choice D reason: Diarrhea and excessive thirst are not typical signs of bowel obstruction. In fact, bowel obstruction usually leads to constipation or the inability to pass stool rather than diarrhea. Excessive thirst could be a sign of dehydration but is not specific to bowel obstruction.

Choice A reason: Hyperbilirubinemia and jaundice are common manifestations of chronic liver disease, but they are not the primary cause of hepatic encephalopathy. These conditions result from the liver's inability to process and clear bilirubin effectively, leading to its accumulation in the blood and subsequent yellowing of the skin and eyes. While these symptoms indicate liver dysfunction, they do not directly cause the neurological impairments seen in hepatic encephalopathy.

Choice B reason: Fluid and electrolyte imbalances are often associated with chronic liver disease and can contribute to various complications, including ascites and edema. However, these imbalances are not the primary cause of hepatic encephalopathy. While electrolyte disturbances, particularly hyponatremia, can exacerbate encephalopathy, the condition itself is more directly linked to the liver's inability to detoxify certain substances, such as ammonia.

Choice C reason: Decreased cerebral blood flow can lead to neurological impairments, but it is not the primary mechanism underlying hepatic encephalopathy. Hepatic encephalopathy primarily results from the accumulation of neurotoxic substances that the liver can no longer effectively process, rather than reduced blood flow to the brain.

Choice D reason: Impaired ammonia metabolism and increased ammonia levels in the blood are the main causes of hepatic encephalopathy. In chronic liver disease, the liver's ability to convert ammonia, a byproduct of protein metabolism, into urea for excretion is compromised. As a result, ammonia accumulates in the blood and crosses the blood-brain barrier, leading to neurotoxicity and the characteristic symptoms of hepatic encephalopathy, such as confusion, altered consciousness, and asterixis (flapping tremor).