Pathophysiology (D236)

Correct Answer

D. Diabetes

Explanation

Diabetes increases the risk for urinary tract infections (UTIs) due to high blood sugar levels, which can lead to glucose in the urine, creating an environment conducive to bacterial growth. Additionally, diabetes can weaken the immune system, making it harder for the body to fight infections.

Why other options are wrong

A. Asthma

Asthma is a respiratory condition and does not directly increase the risk of urinary tract infections. It primarily affects the lungs and airways.

B. High blood pressure

While high blood pressure can affect kidney function and overall health, it is not a direct risk factor for UTIs. The main risk factors are related to the urinary tract and immune function.

C. Obesity

Obesity is a contributing factor for many health conditions, but it is not as directly related to urinary tract infections as diabetes. Although obesity can increase the risk of various infections, diabetes is a more direct cause of UTIs.

Correct Answer

C. Polycystic ovarian syndrome

Explanation

Polycystic ovarian syndrome (PCOS) is the most likely diagnosis for a female patient with irregular menstrual cycles, hirsutism (excessive hair growth), and elevated androgen levels. PCOS is characterized by hormonal imbalances, including elevated androgens, which can lead to symptoms such as irregular periods and hirsutism. It is a common condition that affects women of reproductive age.

Why other options are wrong

A. Hyperthyroidism

This is incorrect because hyperthyroidism typically causes symptoms such as weight loss, rapid heart rate, and increased sweating, but it does not directly cause hirsutism or elevated androgen levels. Irregular menstrual cycles may occur in hyperthyroidism, but elevated androgens are not a hallmark feature.

B. Cushing disease

This is incorrect because Cushing disease, caused by an overproduction of cortisol, can lead to symptoms such as weight gain, thinning skin, and high blood pressure, but it does not typically cause elevated androgens leading to hirsutism or irregular periods.

D. Menopause

This is incorrect because menopause typically occurs later in life and is characterized by the cessation of menstruation, not by elevated androgen levels or hirsutism. Menopausal women may experience irregular periods, but the hormonal imbalance seen in PCOS is more likely to be the cause of these symptoms.

Correct Answer

C. Electrolyte abnormalities

Explanation

Continuous renal replacement therapy (CRRT) is often used in critically ill patients who experience severe kidney failure. One of the key indications for CRRT is the presence of significant electrolyte abnormalities, such as severe hyperkalemia, hyperphosphatemia, or acidosis, that cannot be corrected by other means. These abnormalities can lead to life-threatening arrhythmias or metabolic disturbances, making CRRT necessary to remove waste products and restore electrolyte balance.

Why other options are wrong

A. Nausea – Nausea is a common symptom of many conditions, including kidney failure, but it is not specific enough to require CRRT. Nausea can often be managed with other treatments and does not necessarily indicate the need for CRRT.

B. High blood pressure – While high blood pressure can be a complication of kidney disease, it is not an automatic indication for CRRT. Blood pressure can often be controlled with medications, and CRRT is typically reserved for more severe kidney dysfunction.

D. Fatigue – Fatigue is a common symptom of kidney disease, but it alone does not indicate the need for CRRT. Treatment for fatigue is generally aimed at addressing the underlying kidney dysfunction and may not require continuous renal replacement therapy.

Correct Answer

A. Diabetes

Explanation

Diabetes is one of the most common causes of erectile dysfunction (ED) because it can damage the blood vessels and nerves that are crucial for normal erectile function. Poorly controlled blood sugar levels in diabetes can lead to neuropathy and reduced blood flow, both of which interfere with the ability to achieve or maintain an erection.

Why other options are wrong

B. Obesity

While obesity is a contributing factor to erectile dysfunction due to its association with conditions such as diabetes and hypertension, it is not the most direct cause. Obesity can exacerbate ED, but diabetes is a more common and specific cause.

C. Hypertension

Hypertension can lead to erectile dysfunction by damaging blood vessels and reducing blood flow to the penis, but it is often secondary to other conditions like diabetes. Though it plays a role, diabetes is a more frequent and direct cause of ED.

D. Anxiety

Anxiety can cause temporary erectile dysfunction, particularly in performance-related situations, but it is not a common long-term cause compared to conditions like diabetes. Chronic ED is more often associated with physical health issues such as diabetes, obesity, and hypertension.

Correct Answer

C. Draws water into blood vessels

Explanation

Oncotic pressure, also known as colloid osmotic pressure, is exerted by plasma proteins (mainly albumin) in the blood. This pressure helps draw water from the interstitial fluid back into the capillaries, preventing excessive fluid accumulation in tissues (edema). It plays a crucial role in maintaining blood volume and circulation.

Why other options are wrong

A. Pushes water out of blood vessels

This describes hydrostatic pressure, not oncotic pressure. Hydrostatic pressure is generated by the pumping action of the heart and tends to push fluid out of capillaries.

B. Controls electrolyte balance

Oncotic pressure does not directly control electrolyte balance. Electrolyte balance is primarily maintained by the kidneys and various transport mechanisms across cell membranes.

D. Regulates blood pressure

Although oncotic pressure indirectly affects blood pressure by influencing blood volume, blood pressure is primarily regulated by the heart, blood vessel tone, and kidney function through mechanisms like the renin-angiotensin-aldosterone system.

Correct Answer

D. Stage V

Explanation

At Stage V of chronic kidney disease, also known as end-stage renal disease (ESRD), kidney function is severely impaired, and patients typically require dialysis or a kidney transplant to survive. The GFR at this stage is usually less than 15 mL/min, which indicates that the kidneys are functioning at less than 15% of their normal capacity, and renal replacement therapy is necessary.

Why other options are wrong

A. Stage IV

Stage IV CKD indicates severe kidney damage with a GFR of 15-29 mL/min. While this stage requires close monitoring and possible preparations for dialysis or transplant, it does not yet necessitate dialysis or a transplant.

B. Stage III

Stage III CKD indicates moderate kidney damage with a GFR of 30-59 mL/min. Dialysis or a transplant is not typically required at this stage, but treatment focuses on slowing the progression of kidney damage and managing complications.

C. Stage I

Stage I CKD represents mild kidney damage with a GFR of 90 mL/min or higher. Patients at this stage usually have no symptoms, and dialysis or a transplant is not needed. Treatment focuses on controlling risk factors and monitoring kidney function.

Correct Answer

A. Pituitary

Explanation

Secondary hypothyroidism occurs when there is a dysfunction in the pituitary gland, which fails to produce adequate thyroid-stimulating hormone (TSH) to stimulate the thyroid gland. As a result, the thyroid gland does not produce enough thyroid hormones, even though it is structurally normal. The dysfunction is at the level of the pituitary, not the thyroid itself.

Why other options are wrong

B. Pancreas

This is incorrect because the pancreas is not involved in the regulation of thyroid hormones. The pancreas primarily regulates blood sugar levels through insulin and glucagon, and its dysfunction leads to disorders such as diabetes, not hypothyroidism.

C. Thyroid

This is incorrect because in secondary hypothyroidism, the thyroid gland is typically normal. The problem lies in the pituitary gland's inability to produce enough TSH, so the thyroid is not stimulated to produce sufficient thyroid hormones.

D. Adrenal

This is incorrect because adrenal dysfunction, such as in Addison's disease, affects the production of cortisol and other hormones, not thyroid hormones. Secondary hypothyroidism specifically involves a problem with the pituitary gland.

Correct Answer

C. Causes vasoconstriction

Explanation

The RAAS (Renin-Angiotensin-Aldosterone System) helps maintain blood pressure primarily through vasoconstriction. When blood pressure drops, the kidneys release renin, which leads to the production of angiotensin II. Angiotensin II is a potent vasoconstrictor that narrows blood vessels, increasing vascular resistance and raising blood pressure. Additionally, angiotensin II stimulates the release of aldosterone, which promotes sodium and water retention, further increasing blood volume and pressure.

Why other options are wrong

A. Decreases sodium retention – The RAAS system increases sodium retention through aldosterone, not decreases it. Increased sodium retention leads to increased water retention, which helps raise blood pressure.

B. Promotes vasodilation – The RAAS system does the opposite by promoting vasoconstriction, not vasodilation. Vasodilation would lower blood pressure, which is not the primary function of RAAS.

D. Reduces blood volume – The RAAS system increases blood volume by retaining sodium and water, which helps restore and maintain blood pressure, rather than reducing it.

Correct Answer

A. Pyelonephritis (UTI)

Explanation

Patients with multiple sclerosis (MS) are at increased risk for urinary tract infections (UTIs), including pyelonephritis, due to bladder dysfunction. MS can cause neurogenic bladder, leading to urinary retention and incomplete emptying of the bladder, creating an environment for bacterial growth. Symptoms of a UTI in MS patients may include fever, pain, and changes in urinary habits, which can lead to pyelonephritis if untreated.

Why other options are wrong

B. Acute pancreatitis – Acute pancreatitis is characterized by sudden severe abdominal pain, often due to gallstones or alcohol consumption. While MS can cause a variety of neurological symptoms, pancreatitis is not typically associated with MS.

C. Cholecystitis – Cholecystitis, or inflammation of the gallbladder, usually presents with right upper quadrant abdominal pain, nausea, and vomiting. It is not commonly linked to multiple sclerosis.

D. Appendicitis – Appendicitis is characterized by sharp abdominal pain, typically starting near the belly button and moving to the lower right abdomen. While it is a common cause of abdominal pain, it is not typically related to multiple sclerosis.