A client with acquired immune deficiency syndrome (AIDS) and Pneumocystis jiroveci pneumonia has a CD4+ T cell count of 200 cells/mm³ (20%). The client asks the nurse why they have these recurring massive infections. Which pathophysiologic mechanism should the nurse describe in response to this client's question?

Reference Range:
T-helper CD4 cells [600 to 1500 cells/mm³ (60 to 75%)]

Choice A reason: This is correct because abdominal obesity, also known as central obesity or visceral fat, is one of the criteria for diagnosing metabolic syndrome and a major risk factor for diabetes mellitus and vascular disease. Abdominal obesity is defined as having a waist circumference of more than 40 inches (102 cm) for men or 35 inches (88 cm) for women. Abdominal obesity can increase insulin resistance, inflammation, and blood pressure, which can lead to impaired glucose metabolism and cardiovascular complications.

Choice B reason: This is correct because blood pressure of 150/96 mm Hg is another criterion for diagnosing metabolic syndrome and a significant risk factor for diabetes mellitus and vascular disease. Blood pressure is defined as the force exerted by blood against the walls of blood vessels. Normal blood pressure is less than 120/80 mm Hg, while high blood pressure (hypertension) is 140/90 mm Hg or higher. High blood pressure can damage the blood vessels and organs, such as the heart, kidneys, eyes, and brain, and increase the risk of heart attack, stroke, kidney failure, and vision loss.

Choice C reason: This is incorrect because elevated high density lipoproteins (HDL), also known as good cholesterol, are not a criterion for diagnosing metabolic syndrome or a risk factor for diabetes mellitus and vascular disease. In fact, HDL are beneficial for cardiovascular health because they help remove excess cholesterol from the blood and prevent plaque buildup in the arteries. Normal HDL levels are 40 mg/dL (1.0 mmol/L) or higher for men and 50 mg/dL (1.3 mmol/L) or higher for women.

Choice D reason: This is correct because increased triglyceride levels are another criterion for diagnosing metabolic syndrome and a risk factor for diabetes mellitus and vascular disease. Triglycerides are a type of fat that circulates in the blood and provides energy to cells. Normal triglyceride levels are less than 150 mg/dL (1.7 mmol/L), while high triglyceride levels are 200 mg/dL (2.3 mmol/L) or higher. High triglyceride levels can increase insulin resistance, inflammation, and blood clotting, which can impair glucose metabolism and increase the risk of heart attack and stroke.

Choice E reason: This is correct because hyperglycemia, also known as high blood sugar, is another criterion for diagnosing metabolic syndrome and a hallmark of diabetes mellitus. Hyperglycemia occurs when the body cannot produce enough insulin or use it properly to regulate the amount of glucose in the blood. Normal blood glucose levels are 70 to 99 mg/dL (3.9 to 5.5 mmol/L) before meals and less than 140 mg/dL (7.8 mmol/L) two hours after meals, while hyperglycemia is 126 mg/dL (7.0 mmol/L) or higher before meals or 200 mg/dL (11.1 mmol/L) or higher two hours after meals. Hyperglycemia can damage the blood vessels and organs, such as the eyes, kidneys, nerves, and feet, and increase the risk of infections, ulcers, amputations, and diabetic ketoacidosis.

Choice F reason: This is incorrect because hypothyroidism, also known as underactive thyroid, is not a criterion for diagnosing metabolic syndrome or a direct risk factor for diabetes mellitus and vascular disease. Hypothyroidism occurs when the thyroid gland does not produce enough thyroid hormones, which regulate the body's metabolism, growth, and development. Hypothyroidism can cause symptoms such as fatigue, weight gain, cold intolerance, dry skin, hair loss, constipation, and depression. However, hypothyroidism does not affect the blood glucose or lipid levels directly, but rather indirectly through its effects on weight and appetite.

Choice A reason: Rocky Mountain spotted fever is not the most likely condition for the client who has a severe headache, fever, nuchal rigidity, and a petechial rash on arms and legs. Rocky Mountain spotted fever is a bacterial infection transmitted by ticks that causes a distinctive rash that usually begins on the wrists and ankles and spreads to the rest of the body. The rash is not limited to the arms and legs, and the client may also have other symptoms such as nausea, vomiting, abdominal pain, and muscle aches.

Choice B reason: Intracerebral hemorrhage is not the most likely condition for the client who has a severe headache, fever, nuchal rigidity, and a petechial rash on arms and legs. Intracerebral hemorrhage is a type of stroke that occurs when a blood vessel bursts inside the brain, causing bleeding and swelling. The rash is not a typical sign of intracerebral hemorrhage, and the client may also have other symptoms such as weakness, numbness, vision loss, confusion, and loss of consciousness.

Choice C reason: Cerebrovascular accident (CVA) is not the most likely condition for the client who has a severe headache, fever, nuchal rigidity, and a petechial rash on arms and legs. CVA is another term for stroke, which occurs when the blood supply to a part of the brain is interrupted, causing brain tissue damage. The rash is not a common sign of CVA, and the client may also have other symptoms such as facial drooping, slurred speech, difficulty swallowing, paralysis, and cognitive impairment.

Choice D reason: Meningococcal meningitis is the most likely condition for the client who has a severe headache, fever, nuchal rigidity, and a petechial rash on arms and legs. Meningococcal meningitis is a bacterial infection that causes inflammation of the membranes that cover the brain and spinal cord. The rash is a characteristic sign of meningococcal meningitis, which can appear as small red or purple spots that do not fade when pressed. The client may also have other symptoms such as nausea, vomiting, sensitivity to light, confusion, and seizures.