1. A 66-year-old man with type 2 diabetes mellitus and heart failure with reduced ejection fraction (left ventricular ejection fraction 30%) is on guideline-directed medical therapy including a beta-blocker, sacubitril/valsartan, and a mineralocorticoid receptor antagonist. His estimated glomerular filtration rate (eGFR) is 28 mL/min/1.73 m2. He has no peripheral arterial disease. Which is the most appropriate addition to reduce his risk of heart failure hospitalization?
A) No SGLT-2 inhibitor can be added because his eGFR of 28 is below the glycemic threshold of approximately 45 mL/min/1.73 m2
B) Canagliflozin, because it is the preferred SGLT-2 inhibitor for heart failure with reduced ejection fraction at this eGFR
C) Dapagliflozin or empagliflozin, because their heart failure indication extends to a cardiorenal eGFR floor of roughly 20 to 25 mL/min/1.73 m2 and both have proven reduction in heart failure hospitalization
D) Ertugliflozin, because it has the strongest dedicated heart failure outcome data of the class
E) A second renin-angiotensin system blocker, since SGLT-2 inhibitors are contraindicated once a mineralocorticoid receptor antagonist is in use
ANSWER: C
Rationale:
This patient has heart failure with reduced ejection fraction on optimized guideline-directed therapy and an eGFR of 28 mL/min/1.73 m2. Dapagliflozin and empagliflozin carry proven heart failure benefit (reduced heart failure hospitalization and cardiovascular death) and their heart failure indication extends down to a cardiorenal eGFR floor of roughly 20 to 25 mL/min/1.73 m2, so either can be started at an eGFR of 28.
Option A: Option A is incorrect because the approximately 45 mL/min/1.73 m2 figure is the glycemic threshold, not the cardiorenal floor; the heart failure indication permits use at this eGFR.
Option B: Option B is incorrect because canagliflozin is not the preferred heart failure agent and carries the canagliflozin-specific amputation signal; dapagliflozin and empagliflozin are the heart-failure-indicated agents.
Option D: Option D is incorrect because ertugliflozin has no proven dedicated heart failure outcome benefit and lacks a heart failure indication.
Option E: Option E is incorrect because SGLT-2 inhibitors are not contraindicated alongside a mineralocorticoid receptor antagonist; adding a second renin-angiotensin system blocker would be inappropriate and would not provide the heart failure benefit sought.
2. A 58-year-old woman with type 2 diabetes mellitus has diabetic kidney disease with an eGFR of 40 mL/min/1.73 m2 and a urinary albumin-to-creatinine ratio of 600 mg/g. She is on a maximally tolerated angiotensin receptor blocker. What intervention most directly reduces her risk of progression to end-stage kidney disease?
A) Add an SGLT-2 inhibitor (such as canagliflozin or dapagliflozin), which reduces the composite renal outcome of end-stage kidney disease, doubling of serum creatinine, and renal or cardiovascular death in this population
B) Stop the angiotensin receptor blocker and rely on glycemic control alone to slow progression
C) Add a second angiotensin receptor blocker to achieve dual renin-angiotensin blockade for additive renal protection
D) Add a thiazolidinedione, which is the agent with proven reduction in progression of diabetic kidney disease
E) Avoid any further therapy because nothing beyond the angiotensin receptor blocker affects renal outcomes in diabetic kidney disease
ANSWER: A
Rationale:
In a patient with type 2 diabetes mellitus, reduced eGFR, and substantial albuminuria already on maximally tolerated renin-angiotensin blockade, adding an SGLT-2 inhibitor provides additional renoprotection, reducing the composite renal outcome (end-stage kidney disease, doubling of serum creatinine, and renal or cardiovascular death). This benefit, demonstrated for agents such as canagliflozin and dapagliflozin in dedicated renal trials, is largely hemodynamic and independent of glycemic improvement.
Option B: Option B is incorrect because stopping the angiotensin receptor blocker removes proven renoprotection; glycemic control alone is insufficient.
Option C: Option C is incorrect because dual renin-angiotensin blockade increases the risk of hyperkalemia and acute kidney injury without improving outcomes and is not recommended.
Option D: Option D is incorrect because thiazolidinediones are not the proven agents for slowing diabetic kidney disease progression and carry fluid-retention risk problematic in this setting.
Option E: Option E is incorrect because SGLT-2 inhibitor therapy adds meaningful renal benefit beyond the angiotensin receptor blocker, so withholding further therapy is inappropriate.
3. A 74-year-old woman has heart failure with preserved ejection fraction (left ventricular ejection fraction 58%) with recurrent dyspnea and a prior heart failure hospitalization. She does not have diabetes and her HbA1c is normal. Her eGFR is 55 mL/min/1.73 m2. Which therapy has demonstrated reduction in the composite of cardiovascular death or heart failure hospitalization in her condition?
A) No SGLT-2 inhibitor is appropriate, because these agents have benefit only in reduced ejection fraction heart failure
B) No SGLT-2 inhibitor is appropriate, because she does not have diabetes and the drugs require a glycemic indication
C) A thiazolidinedione, which is the proven agent for preserved ejection fraction heart failure
D) Empagliflozin, which reduced the composite of cardiovascular death or heart failure hospitalization in preserved ejection fraction heart failure regardless of diabetes status
E) High-dose loop diuretic monotherapy, which is the only intervention shown to reduce hospitalization in preserved ejection fraction heart failure
ANSWER: D
Rationale:
Empagliflozin demonstrated a significant reduction in the composite of cardiovascular death or heart failure hospitalization in heart failure with preserved ejection fraction, and this benefit applies regardless of diabetes status; it is appropriate for a non-diabetic patient with preserved ejection fraction heart failure and adequate eGFR.
Option A: Option A is incorrect because the benefit extends to preserved ejection fraction heart failure, not solely reduced ejection fraction.
Option B: Option B is incorrect because the heart failure indication does not require diabetes or a glycemic indication.
Option C: Option C is incorrect because thiazolidinediones are not proven for preserved ejection fraction heart failure and can worsen fluid retention.
Option E: Option E is incorrect because loop diuretics relieve congestion symptomatically but have not been shown to reduce the cardiovascular death or heart failure hospitalization composite; empagliflozin has.
4. A 49-year-old man with type 2 diabetes mellitus on empagliflozin presents to the emergency department with two days of nausea, vomiting, abdominal discomfort, and malaise after a recent viral illness with poor oral intake. His plasma glucose is 180 mg/dL. What is the most appropriate immediate step?
A) Reassure the patient that diabetic ketoacidosis is excluded by the near-normal glucose and discharge him with antiemetics
B) Measure serum or urine ketones and arterial or venous blood gas, hold the empagliflozin, and evaluate for euglycemic diabetic ketoacidosis despite the near-normal glucose
C) Increase the empagliflozin dose to improve glycemic control during the acute illness
D) Administer a large intravenous dextrose bolus, since the glucose of 180 indicates impending hypoglycemia
E) Attribute the presentation to genital mycotic infection and begin empiric antifungal therapy
ANSWER: B
Rationale:
This patient on an SGLT-2 inhibitor has nausea, vomiting, and reduced intake during an acute illness, the classic setting for euglycemic diabetic ketoacidosis. Because ketoacidosis can occur with only modestly elevated glucose, the correct step is to measure ketones and a blood gas, hold the drug, and evaluate for euglycemic diabetic ketoacidosis despite the near-normal glucose.
Option A: Option A is incorrect because a near-normal glucose does not exclude euglycemic ketoacidosis; discharging him risks missing a dangerous diagnosis.
Option C: Option C is incorrect because increasing the dose during an acute precipitating illness worsens ketoacidosis risk.
Option D: Option D is incorrect because a glucose of 180 mg/dL is not hypoglycemia, and a dextrose bolus does not address the underlying ketoacidosis evaluation.
Option E: Option E is incorrect because, although genital mycotic infection is common with the class, the presenting symptoms mandate evaluation for euglycemic ketoacidosis first.
5. A 62-year-old man with type 2 diabetes mellitus, established atherosclerotic cardiovascular disease, peripheral arterial disease, and a prior transmetatarsal amputation needs an SGLT-2 inhibitor for cardiovascular risk reduction. Which agent selection is best supported and why?
A) Canagliflozin, because its lower-extremity effects improve perfusion in patients with peripheral arterial disease
B) Any SGLT-2 inhibitor is equally appropriate, because the amputation signal is a uniform class effect with no agent distinction
C) Dapagliflozin or empagliflozin rather than canagliflozin, because the increased lower-extremity amputation signal is considered largely canagliflozin-specific, making a different agent the more prudent choice in a patient with peripheral arterial disease and prior amputation
D) No SGLT-2 inhibitor should be used, because the entire class is contraindicated in any patient with peripheral arterial disease
E) Ertugliflozin, because it carries the strongest cardiovascular outcome benefit and the lowest amputation risk of the class
ANSWER: C
Rationale:
The increased lower-extremity amputation signal was identified with canagliflozin and is considered largely canagliflozin-specific rather than a consistent class effect; in a patient with peripheral arterial disease and a prior amputation, selecting dapagliflozin or empagliflozin (both of which carry proven cardiovascular benefit) is the more prudent choice.
Option A: Option A is incorrect because the canagliflozin signal reflects increased amputation risk, not improved perfusion.
Option B: Option B is incorrect because the signal is not uniform across the class; agent choice matters.
Option D: Option D is incorrect because peripheral arterial disease does not contraindicate the entire class; an agent other than canagliflozin can be used with appropriate foot monitoring.
Option E: Option E is incorrect because ertugliflozin lacks demonstrated cardiovascular outcome superiority and is not the agent with the strongest benefit.
6. An 82-year-old woman with type 2 diabetes mellitus and heart failure has a baseline blood pressure of 104/62 mmHg. She takes furosemide and lisinopril. Her clinician wishes to start an SGLT-2 inhibitor. What is the most appropriate initiation approach?
A) Start at the maximum dose immediately and add another antihypertensive to ensure adequate dosing
B) Defer the SGLT-2 inhibitor indefinitely, because it cannot be used in any patient on a loop diuretic and a renin-angiotensin blocker
C) Increase the furosemide dose concurrently to counteract the fluid retention the SGLT-2 inhibitor will cause
D) Start the SGLT-2 inhibitor and discontinue the lisinopril, since the two cannot be used together
E) Initiate at a lower dose with blood pressure monitoring and consider reducing the furosemide dose, because the osmotic diuresis and natriuresis of the SGLT-2 inhibitor add to the volume depletion from the loop diuretic and the blood-pressure lowering of the renin-angiotensin blocker, a risk amplified in an elderly patient with low baseline blood pressure
ANSWER: E
Rationale:
In an elderly patient with low-normal blood pressure on a loop diuretic and a renin-angiotensin blocker, the osmotic diuresis and natriuresis of an SGLT-2 inhibitor add to existing volume depletion and blood-pressure lowering. The appropriate approach is cautious initiation at a lower dose with blood pressure monitoring and consideration of reducing the concurrent loop diuretic.
Option A: Option A is incorrect because starting at maximum dose and adding another antihypertensive ignores the additive volume and blood-pressure risk.
Option B: Option B is incorrect because SGLT-2 inhibitors can be used with loop diuretics and renin-angiotensin blockers with appropriate precautions.
Option C: Option C is incorrect because SGLT-2 inhibitors cause volume loss rather than retention, so increasing the loop diuretic would worsen depletion.
Option D: Option D is incorrect because SGLT-2 inhibitors and renin-angiotensin blockers are appropriately used together, particularly in heart failure; stopping lisinopril is unwarranted.
7. A 57-year-old man with type 2 diabetes mellitus on dapagliflozin is scheduled for an elective total knee arthroplasty in one week. What is the correct perioperative plan for the dapagliflozin?
A) Continue dapagliflozin through the morning of surgery to avoid perioperative hyperglycemia
B) Stop dapagliflozin 3 to 4 days before surgery and resume it postoperatively only once he is eating and drinking normally with negative ketones and no ongoing infection
C) Hold dapagliflozin only on the morning of surgery and resume it that same evening regardless of oral intake
D) Continue dapagliflozin and double the dose during the perioperative fasting period to maintain glycemic control
E) Stop dapagliflozin the night before surgery and resume it immediately in the recovery room
ANSWER: B
Rationale:
Because SGLT-2 inhibitors predispose to perioperative euglycemic diabetic ketoacidosis during fasting and surgical stress, the established protocol is to discontinue the drug 3 to 4 days before planned major surgery and resume it only after the patient is eating and drinking normally, with negative ketones and no ongoing infection.
Option A: Option A is incorrect because continuing through the morning of surgery leaves the patient exposed to perioperative euglycemic ketoacidosis.
Option C: Option C is incorrect because a single morning-of hold is insufficient given the drug's pharmacodynamic persistence, and resuming the same evening before normal intake is premature.
Option D: Option D is incorrect because increasing the dose during fasting raises the risk of euglycemic ketoacidosis.
Option E: Option E is incorrect because stopping only the night before does not allow adequate washout, and resuming in the recovery room before normal oral intake is premature.
8. A 68-year-old woman with type 2 diabetes mellitus has a prior ischemic stroke (established atherosclerotic disease) and heart failure with reduced ejection fraction. She is on metformin with an HbA1c slightly above goal. Which add-on strategy best addresses both her atherosclerotic and heart failure risks?
A) Add a sulfonylurea, which provides both atherosclerotic and heart failure outcome benefit
B) Add a second SGLT-2 inhibitor to a first to cover both risk pathways through additive glycosuria
C) Add a dipeptidyl peptidase-4 inhibitor, which reduces both stroke and heart failure hospitalization
D) Add an SGLT-2 inhibitor for heart failure benefit and a glucagon-like peptide-1 receptor agonist for atherosclerotic (notably stroke) risk reduction, since the two classes address complementary risk pathways
E) Add a thiazolidinedione, which is preferred in heart failure with reduced ejection fraction and reduces atherosclerotic events
ANSWER: D
Rationale:
This patient has both established atherosclerotic disease (prior stroke) and heart failure. An SGLT-2 inhibitor addresses the heart failure risk through its hemodynamic, heart-failure-oriented benefit, while a glucagon-like peptide-1 receptor agonist addresses atherosclerotic risk, notably reducing stroke and major adverse cardiovascular events; combining the two classes targets complementary pathways.
Option A: Option A is incorrect because sulfonylureas do not provide proven atherosclerotic or heart failure outcome benefit.
Option B: Option B is incorrect because two SGLT-2 inhibitors should never be combined and would not address the atherosclerotic component.
Option C: Option C is incorrect because dipeptidyl peptidase-4 inhibitors do not reduce stroke, and some carry heart failure hospitalization concerns rather than benefit.
Option E: Option E is incorrect because thiazolidinediones cause fluid retention and are contraindicated in symptomatic heart failure with reduced ejection fraction.
9. A 54-year-old woman with type 2 diabetes mellitus started canagliflozin two months ago for glycemic control and cardiovascular benefit. She reports a first episode of vulvovaginal candidiasis with typical itching and discharge. She is otherwise well and her glycemic control has improved. What is the most appropriate management?
A) Treat the candidiasis with standard topical or oral antifungal therapy and continue the SGLT-2 inhibitor, counseling her on genital hygiene, since most genital mycotic infections are mild to moderate and do not require drug discontinuation unless recurrent or severe
B) Permanently discontinue the SGLT-2 inhibitor immediately, as a single episode of candidiasis is an absolute contraindication to continued use
C) Switch her to insulin monotherapy, since genital mycotic infection indicates failure of SGLT-2 inhibitor therapy
D) Withhold antifungal treatment and simply lower the SGLT-2 inhibitor dose, since treating the infection while continuing therapy is unsafe
E) Begin chronic suppressive systemic antifungal therapy indefinitely for any patient on an SGLT-2 inhibitor
ANSWER: A
Rationale:
Genital mycotic infections are the most common adverse effect of SGLT-2 inhibitors and result from glucosuria favoring Candida growth. Most are mild to moderate, respond to standard topical or oral antifungal treatment, and do not require drug discontinuation unless they are recurrent or severe; counseling on genital hygiene is appropriate. For this first, uncomplicated episode in a patient deriving benefit, treating the infection and continuing the drug is correct.
Option B: Option B is incorrect because a single episode of candidiasis is not an absolute contraindication; discontinuation is reserved for recurrent or severe cases.
Option C: Option C is incorrect because a mycotic infection does not indicate therapeutic failure and does not warrant switching to insulin monotherapy.
Option D: Option D is incorrect because the infection should be treated; withholding antifungal therapy is inappropriate, and continuing the drug during treatment is acceptable.
Option E: Option E is incorrect because indefinite chronic suppressive antifungal therapy is not indicated for all patients on the class.
10. A 60-year-old man with type 2 diabetes mellitus on an SGLT-2 inhibitor presents with 24 hours of rapidly worsening perineal pain, swelling, and erythema extending toward the scrotum, with fever, tachycardia, and disproportionate pain on examination. What is the most appropriate immediate management?
A) Prescribe an outpatient course of oral antifungal therapy and arrange follow-up in two weeks
B) Continue the SGLT-2 inhibitor and apply topical antibiotic ointment to the affected area
C) Reduce the SGLT-2 inhibitor dose and observe for 48 hours before deciding on further action
D) Discharge with reassurance, since perineal symptoms in patients on this class are uniformly benign
E) Discontinue the SGLT-2 inhibitor and obtain emergent surgical consultation for suspected Fournier gangrene, initiating broad-spectrum antibiotics and resuscitation, because early surgical debridement is critical to survival
ANSWER: E
Rationale:
Rapidly progressive perineal pain, swelling, and erythema with systemic toxicity and pain out of proportion in a patient on an SGLT-2 inhibitor is concerning for Fournier gangrene, a life-threatening necrotizing fasciitis of the perineum and genitalia. Management requires discontinuing the SGLT-2 inhibitor, obtaining emergent surgical consultation, and initiating broad-spectrum antibiotics and resuscitation, because early surgical debridement is critical to survival.
Option A: Option A is incorrect because outpatient antifungal therapy dangerously delays surgical care of a necrotizing infection.
Option B: Option B is incorrect because continuing the drug and applying topical antibiotic fails to address a surgical emergency.
Option C: Option C is incorrect because dose reduction and 48-hour observation delay definitive treatment of a fulminant infection.
Option D: Option D is incorrect because these symptoms are not benign; they represent a surgical emergency requiring immediate action.
11. A 31-year-old woman with type 1 diabetes mellitus was started on an SGLT-2 inhibitor by an outside provider as adjunct to insulin to improve glycemic variability. She presents with nausea, vomiting, and Kussmaul respirations; plasma glucose is 210 mg/dL, and labs confirm a high anion-gap metabolic acidosis with elevated beta-hydroxybutyrate. Which statement best captures the clinical issue?
A) Her presentation excludes ketoacidosis because the glucose is only 210 mg/dL, so an alternative diagnosis should be sought
B) SGLT-2 inhibitors are FDA-approved in type 1 diabetes mellitus, so this complication was unexpected and unrelated to the drug
C) This is euglycemic diabetic ketoacidosis: SGLT-2 inhibitors substantially increase ketoacidosis risk in type 1 diabetes mellitus (where they are not FDA-approved), the drug should be discontinued, and she should be treated for ketoacidosis with insulin, fluids, and glucose as needed
D) The SGLT-2 inhibitor should be continued and her insulin reduced, since the acidosis reflects insulin excess rather than ketoacidosis
E) This is hyperosmolar hyperglycemic state, which is the characteristic SGLT-2 inhibitor complication in type 1 diabetes mellitus
ANSWER: C
Rationale:
This is euglycemic diabetic ketoacidosis. SGLT-2 inhibitors markedly increase the risk of ketoacidosis in type 1 diabetes mellitus, where they are not FDA-approved, because relative insulin deficiency drives ketogenesis while glycosuria keeps glucose only modestly elevated. The correct management is to discontinue the SGLT-2 inhibitor and treat the ketoacidosis with insulin, fluids, and glucose as needed.
Option A: Option A is incorrect because a glucose of 210 mg/dL with a high anion-gap acidosis and elevated beta-hydroxybutyrate is diagnostic of euglycemic ketoacidosis, not a reason to exclude it.
Option B: Option B is incorrect because SGLT-2 inhibitors are not FDA-approved in type 1 diabetes mellitus, and this complication is a recognized risk of such off-label use.
Option D: Option D is incorrect because the acidosis is a ketoacidosis driven by ketogenesis, not insulin excess, and continuing the drug while reducing insulin would worsen it.
Option E: Option E is incorrect because the picture is a ketoacidosis with elevated ketones, not a hyperosmolar hyperglycemic state.
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