Internal Medicine

Match each patient's clinical presentation of chronic cough with the most appropriate initial pharmacological intervention or management step.

A 72-hour fasting test is conducted to evaluate adult patients presenting with recurrent episodes of spontaneous fasting hypoglycemia. Match each of the following biochemical profiles (all obtained at the time of symptomatic hypoglycemia with plasma glucose < 45 mg/dL) with the most likely underlying etiology.

Evaluation of an uncommunicative $76$-year-old male takes place in the emergency department after his family found him severely short of breath and somnolent. Medical history includes ischemic cardiomyopathy, chronic obstructive pulmonary disease (COPD), and osteoarthritis. Vital signs include a blood pressure of $165/95 \text{ mm Hg}$, pulse of $112/\text{min}$, respirations of $28/\text{min}$, and oxygen saturation of $85\%$ on room air. He is afebrile. Physical examination reveals labored breathing with use of accessory muscles. Auscultation of the lungs demonstrates diffuse wheezing and bilateral crackles extending to the mid-lung fields. Jugular venous distention is present at $12 \text{ cm H}_2\text{O}$. There is $2+$ pitting edema of the lower extremities.

Laboratory results are as follows:
Leukocyte count: $8,500/\mu \text{L}$ (Normal: $4,500-11,000/\mu \text{L}$)
Brain natriuretic peptide (BNP): $850 \text{ pg/mL}$ (Normal: $< 100 \text{ pg/mL}$)
Free T4: $0.7 \text{ ng/dL}$ (Normal: $0.9-2.4 \text{ ng/dL}$)
Thyroid-stimulating hormone (TSH): $1.0 \text{ mU/L}$ (Normal: $0.4-4.0 \text{ mU/L}$)

Arterial blood gas (room air):
pH: $7.24$
PaCO $_2$: $62 \text{ mm Hg}$
PaO $_2$: $54 \text{ mm Hg}$
HCO $_3^-$: $26 \text{ mEq/L}$

Chest radiography shows cardiomegaly, bilateral perihilar alveolar opacities, and prominent interlobular septal thickening. Which of the following is the most appropriate initial step in the management of this patient?

Match the following clinical presentations and laboratory profiles with their most likely underlying pathophysiologic diagnosis.

A 47-year-old woman with a history of type 2 diabetes mellitus is evaluated on hospital day 4 for ongoing management of a left foot infection. She initially presented to the emergency department with a deep, purulent ulcer on the plantar surface of her foot, surrounded by a 6-cm area of erythema and induration. On admission, she was febrile and had leukocytosis. She was started on empiric intravenous vancomycin and piperacillin-tazobactam and underwent prompt surgical debridement. The surgeon noted no evidence of bone involvement, which was confirmed by a negative MRI of the foot. Today, her temperature is 37.0°C (98.6°F), blood pressure is 122/78 mm Hg, and pulse is 76/min. The surgical wound is clean with healthy granulation tissue, and the surrounding erythema has nearly resolved. Intraoperative deep tissue cultures now show heavy growth of methicillin-susceptible Staphylococcus aureus (MSSA) and Streptococcus agalactiae. Susceptibility testing indicates both isolates are susceptible to cefazolin, cephalexin, and ampicillin. The MSSA isolate is resistant to clindamycin. Which of the following is the most appropriate next step in pharmacotherapy?

During a health maintenance visit, a 54-year-old man reports a four-month history of worsening sluggishness, generalized muscle aches, and dry skin. He mentions needing to wear a sweater even when indoors. His temperature is $36.0^\circ\text{C}$ ($96.8^\circ\text{F}$), blood pressure is $112/74\text{ mmHg}$, and pulse is $54/\text{min}$. Physical examination reveals a puffy face, nonpitting edema of the lower extremities, and a notably delayed relaxation phase of the deep tendon reflexes. The thyroid gland is not palpable.

Laboratory evaluation shows the following:

Which of the following mechanisms best explains this patient's clinical presentation and laboratory findings?

A 56-year-old man presents to the clinic with a 6-month history of worsening fatigue, generalized weakness, and decreased libido. He also reports new-onset discomfort in his hands, specifically involving the second and third metacarpophalangeal joints. On physical examination, there is hepatomegaly and a grayish-bronze discoloration of his skin. Laboratory studies show a fasting blood glucose level of 142 mg/dL. Thyroid function testing reveals a free thyroxine (T4) level of 0.6 ng/dL (normal: 0.9-1.7 ng/dL) and a thyroid-stimulating hormone (TSH) level of 1.4 mU/L (normal: 0.4-4.2 mU/L). Which of the following is the most likely underlying mechanism for this patient's thyroid laboratory findings?

During a routine prenatal evaluation at 34 weeks gestation, a primigravid patient with a well-documented history of systemic lupus erythematosus reports new-onset swelling in her hands and face over the past week. Her blood pressure today is 152/96 mmHg, which is elevated from a baseline of 110/70 mmHg. Laboratory evaluation reveals a serum creatinine of 1.1 mg/dL (baseline 0.6 mg/dL) and a urine dipstick showing 3+ protein. The physician is attempting to determine whether these findings represent severe preeclampsia or an acute lupus nephritis flare. Which of the following laboratory findings would most specifically support a diagnosis of an active lupus flare in this patient?

Match each specific clinical presentation and isolated pathogen of infective endocarditis with its most appropriate targeted antimicrobial regimen according to current clinical guidelines.

A 24-year-old woman presents to the clinic with a 2-month history of a photosensitive facial rash, profound fatigue, and symmetric inflammatory polyarthralgia. Over the next several months, her disease progresses and she develops significant peripheral edema and frothy urine. Arrange the following diagnostic and therapeutic steps in the optimal chronological sequence for managing this patient's evolving condition, from initial presentation to the long-term management of her organ-threatening disease.

Match each complex clinical scenario and corresponding arterial blood gas/basic metabolic panel profile with the most accurate interpretation of the patient's mixed acid-base disorder. Evaluate the anion gap, delta gap (delta-delta), and appropriate respiratory compensation to determine the correct physiological state.

A $56$-year-old man is brought to the emergency department after vomiting a large amount of bright red blood. He has a history of alcohol use disorder and was diagnosed with cirrhosis two years ago. On arrival, he is lethargic but easily arousable. His temperature is $37.1^\circ\text{C}$ ($98.8^\circ\text{F}$), blood pressure is $88/54\text{ mm Hg}$, pulse is $118/\text{min}$, and respiratory rate is $20/\text{min}$. Physical examination reveals scleral icterus, spider angiomas on the chest, and a distended abdomen with shifting dullness. Arrange the following management steps in the most appropriate chronological sequence for this patient.

A 45-year-old woman presents to the clinic with episodic palpitations, severe headaches, and unprovoked sweating. Her blood pressure during these episodes reaches 190/110 mmHg. The physician suspects a pheochromocytoma. Arrange the following steps in the correct chronological sequence for the standard workup and management of this condition.

A 48-year-old man is hospitalized for the initiation of induction chemotherapy for recently diagnosed Burkitt lymphoma. Twenty-four hours after starting the multi-agent regimen, he develops diffuse muscle cramps, generalized weakness, and nausea. His temperature is $37.2^\circ\text{C}$ ($99.0^\circ\text{F}$), blood pressure is $115/75\text{ mmHg}$, pulse is $112/\text{min}$, and respirations are $18/\text{min}$. Physical examination reveals hyperactive deep tendon reflexes and occasional muscle twitching. Laboratory results are as follows:

* Sodium: $138\text{ mEq/L}$
* Potassium: $7.1\text{ mEq/L}$
* Bicarbonate: $18\text{ mEq/L}$
* Blood urea nitrogen (BUN): $48\text{ mg/dL}$
* Creatinine: $3.2\text{ mg/dL}$ (Baseline: $0.9\text{ mg/dL}$)
* Calcium: $6.2\text{ mg/dL}$
* Phosphorus: $9.0\text{ mg/dL}$
* Uric acid: $15.5\text{ mg/dL}$

An electrocardiogram reveals peaked T waves and a shortened QT interval. Which of the following is the most appropriate immediate next step in management?

An evaluation is requested for a $48$-year-old male who reports a pervasive sense of exhaustion, a $12\text{-kg}$ ($26.5\text{-lb}$) weight gain, and significantly reduced libido over the past eight months. He has no significant past medical history and takes no medications.

Vital signs show a blood pressure of $96/60\text{ mmHg}$ and a heart rate of $54/\text{min}$. Neurologic examination reveals bilateral temporal visual field deficits. Deep tendon reflexes exhibit delayed relaxation.

Laboratory studies yield the following results:

The physician determines that thyroid hormone replacement is indicated. Which of the following is the most critical step to perform prior to initiating this specific therapy?

A 72-year-old man is brought to the emergency department from a nursing home due to altered mental status, fever, and rapid breathing for the past day. He has a history of benign prostatic hyperplasia and type 2 diabetes mellitus. His temperature is $39.1^\circ\text{C}$ ($102.4^\circ\text{F}$), blood pressure is $85/50\text{ mm Hg}$, pulse is $122/\text{min}$, and respiratory rate is $32/\text{min}$. Physical examination reveals a lethargic man with dry mucous membranes and right costovertebral angle tenderness.

Laboratory results are as follows:

Which of the following best describes this patient's primary and concurrent acid-base disturbances?

Match the following classic urinalysis sediment findings with their most likely associated renal pathology.

A 25-year-old female with a history of type 1 diabetes mellitus is brought to the emergency department by her roommate due to severe lethargy and abdominal pain. Over the preceding 48 hours, she has experienced intractable nonbilious emesis and has consequently withheld her scheduled insulin doses. On physical examination, she appears confused and has markedly dry mucous membranes with decreased skin turgor.

Laboratory results:
- Serum $Na^+$: $140 \text{ mEq/L}$
- Serum $K^+$: $3.4 \text{ mEq/L}$
- Serum $Cl^-$: $86 \text{ mEq/L}$
- Serum $HCO_3^-$: $14 \text{ mEq/L}$
- Serum glucose: $545 \text{ mg/dL}$
- Blood urea nitrogen: $38 \text{ mg/dL}$
- Serum creatinine: $1.6 \text{ mg/dL}$

Assuming a normal anion gap of $12 \text{ mEq/L}$ and a normal serum bicarbonate of $24 \text{ mEq/L}$, what is this patient's calculated delta-delta ratio?

Match each clinical scenario with the most appropriate antimicrobial therapy or prophylaxis regimen.

Match each clinical scenario and associated arterial blood gas (ABG) profile with the most accurate description of the primary acid-base disturbance(s). Assume a normal anion gap is $8-12$ mEq/L.