The nurse cares for a client with severe ascites due to alcoholic cirrhosis. Which description best explains the mechanism for ascites development in this client?

Choice A reason: Decreased dietary intake of proteins and vegetables is not the best explanation because it is a factor that affects the nutritional status, not the immune system. Nutritional status is important for maintaining the health and function of the body, but it does not directly cause an increased risk of infection. Proteins and vegetables are sources of essential nutrients, such as amino acids, vitamins, minerals, and antioxidants, that support the growth and repair of the tissues and the prevention of oxidative stress.

Choice B reason: Decreased T cell function and antibody response is the best explanation because it is a factor that affects the immune system, which is the body's defense mechanism against foreign invaders, such as bacteria, viruses, and fungi. The immune system consists of two main components: the innate immunity and the adaptive immunity. The innate immunity is the first line of defense that provides a general and rapid response to any potential threat. The adaptive immunity is the second line of defense that provides a specific and long-lasting response to a particular antigen. T cells and antibodies are part of the adaptive immunity, which recognizes and remembers the antigens that have previously infected the body and eliminates them more efficiently. However, as people age, the T cell function and the antibody response decline, making the older adults more susceptible to infections, especially those that are new or unfamiliar to the body.

Choice C reason: Atrophy of the bone marrow and spleen is not the best explanation because it is a factor that affects the production and storage of immune cells, not the function and response. The bone marrow is the soft tissue inside the bones that produces the blood cells, including the white blood cells, which are the main components of the immune system. The spleen is an organ that filters the blood and removes the old or damaged blood cells, as well as stores some of the white blood cells and platelets. As people age, the bone marrow and the spleen shrink and lose some of their ability to produce and store the immune cells, which can reduce the number and diversity of the immune cells available to fight infections. However, this does not necessarily affect the function and response of the immune cells that are already circulating in the blood.

Choice D reason: Impaired absorption of vitamin B12 is not the best explanation because it is a factor that affects the nervous system and the blood cells, not the immune system. Vitamin B12 is a water-soluble vitamin that is essential for the synthesis of DNA, the maintenance of the myelin sheath, and the formation of red blood cells. As people age, the absorption of vitamin B12 decreases due to the reduced secretion of stomach acid and intrinsic factor, which are needed to break down and bind to the vitamin B12 in the food. This can lead to vitamin B12 deficiency, which can cause symptoms such as fatigue, weakness, numbness, tingling, memory loss, and anemia. Anemia is a condition where the blood has a low level of hemoglobin, which is the protein that carries oxygen in the red blood cells. Anemia can affect the oxygen delivery to the tissues, but it does not directly cause an increased risk of infection.

Choice A reason: Inflammation of white matter in the brain and spinal cord is not the best explanation because it is a condition that affects the transmission of nerve impulses, not the perception of sensory stimuli. White matter is the part of the nervous system that consists of myelinated axons, which are the extensions of nerve cells that carry electrical signals from one cell to another. Inflammation of white matter can be caused by various factors, such as infections, autoimmune diseases, or trauma, and can result in symptoms such as weakness, numbness, or paralysis.

Choice B reason: Increased levels of gamma-aminobutyric acid (GABA) in the brain stem is not the best explanation because it is a condition that affects the regulation of muscle tone, not the perception of sensory stimuli. GABA is a neurotransmitter, which is a chemical messenger that transmits signals between nerve cells. GABA is an inhibitory neurotransmitter, which means that it reduces the activity of the nerve cells that it binds to. GABA is mainly found in the brain stem, which is the part of the brain that connects the spinal cord to the cerebrum and cerebellum, and controls vital functions such as breathing, heart rate, and blood pressure. Increased levels of GABA in the brain stem can cause symptoms such as spasticity, rigidity, or tremors.

Choice C reason: Decreased levels of endorphins in the pons and medulla is not the best explanation because it is a condition that affects the modulation of pain, not the perception of sensory stimuli. Endorphins are neurotransmitters that act as natural painkillers, by binding to the opioid receptors in the brain and spinal cord, and blocking the transmission of pain signals. Endorphins are produced by the pituitary gland and the hypothalamus, which are parts of the brain that regulate the hormonal and nervous systems. The pons and the medulla are parts of the brain stem that are involved in the control of voluntary and involuntary movements, such as chewing, swallowing, coughing, sneezing, and blinking. Decreased levels of endorphins in the pons and the medulla can cause symptoms such as increased sensitivity to pain, anxiety, or depression.

Choice D reason: Hypoxia and necrosis of the parietal lobe neurons is the best explanation because it is a condition that affects the processing of sensory stimuli, such as touch, pain, temperature, and position. The parietal lobe is the part of the cerebrum that is responsible for integrating and interpreting sensory information from different parts of the body. The parietal lobe is divided into two hemispheres, each corresponding to the opposite side of the body. A left-sided intracerebral hemorrhage is a condition where a blood vessel in the left parietal lobe ruptures, causing bleeding and swelling in the brain tissue. This can damage the neurons, which are the nerve cells that communicate with each other and form the basis of the nervous system. Hypoxia and necrosis of the parietal lobe neurons can cause symptoms such as loss of sensation, neglect, or agnosia on the right side of the body.