A 64-year-old man presents to the emergency department due to a 2-week history of progress… — USMLE Step 2 CK

A 64-year-old man presents to the emergency department due to a 2-week history of progressive dyspnea on exertion, orthopnea, and a persistent dry cough. His medical history includes seropositive rheumatoid arthritis, type 2 diabetes mellitus, and a 35-pack-year smoking history. His joint disease was previously inadequately controlled with methotrexate monotherapy, prompting the addition of adalimumab 6 months ago, which has successfully induced clinical remission.

On physical examination, his temperature is $37.4^\circ C$ ( $99.3^\circ F$ ), blood pressure is $148/90\ mmHg$ , heart rate is $108/min$ , and respiratory rate is $24/min$ . Pulse oximetry shows $91\%$ on room air. Jugular venous distention is prominent up to the angle of the mandible while the patient is seated at a 45-degree angle. Auscultation reveals diffuse bilateral expiratory wheezes and coarse crackles at the lung bases. Bilateral 2+ pitting edema is noted up to the mid-calves.

Laboratory results:
Leukocytes: $8,500/mm^3$
Hemoglobin: $11.2\ g/dL$
Brain natriuretic peptide (BNP): $840\ pg/mL$ (Normal $< 100$ )
Thyroid-stimulating hormone (TSH): $3.8\ \mu U/mL$ (Normal $0.5 - 5.0$ )

Arterial blood gas (room air):
pH: $7.48$
$PaCO_2$ : $31\ mmHg$
$PaO_2$ : $64\ mmHg$
$HCO_3^-$ : $23\ mEq/L$

Which of the following is the most appropriate next step in management?

Discontinue adalimumab and initiate intravenous furosemideAnswer
B
Administer systemic corticosteroids, nebulized ipratropium-albuterol, and oral azithromycin
C
Start empirical intravenous piperacillin-tazobactam and vancomycin
D
Administer intravenous sodium bicarbonate to correct the metabolic derangement
E
Initiate oral levothyroxine and order a transthoracic echocardiogram

Answer

The most appropriate management is to discontinue adalimumab and initiate intravenous furosemide.

The correct approach is to discontinue adalimumab and initiate intravenous furosemide. This patient presents with classic signs of acute decompensated heart failure (ADHF), including orthopnea, elevated jugular venous pressure, pulmonary crackles, pitting edema, and a highly elevated BNP. The wheezing he is experiencing is likely 'cardiac asthma' caused by peribronchial edema rather than a primary airway disease. A crucial element of his presentation is the initiation of adalimumab 6 months ago. Adalimumab is a tumor necrosis factor-alpha (TNF-alpha) inhibitor used in the treatment of rheumatoid arthritis. TNF-alpha inhibitors carry a well-documented risk of causing new-onset heart failure or exacerbating existing left ventricular dysfunction. They are contraindicated in patients with moderate to severe heart failure. Therefore, the most appropriate management must involve not only acute diuresis with a loop diuretic (e.g., furosemide) to reduce preload and relieve pulmonary congestion, but also the immediate discontinuation of the offending biologic agent.

Step-by-Step Solution

Evaluate the clinical signs, symptoms, and laboratory data to establish the primary acute diagnosis.

The combination of orthopnea, prominent JVD, bibasilar crackles, pedal edema, and a markedly elevated BNP (

840\ pg/mL

) confirms a diagnosis of acute decompensated heart failure (ADHF).

Accurate identification of the acute presentation is required to avoid confounding diagnoses like COPD exacerbation (despite the wheezing or 'cardiac asthma').

Review the patient's pharmacologic history for potential triggers of the acute decompensation.

The patient was started on adalimumab 6 months ago for refractory rheumatoid arthritis.

Identifying drug-induced etiologies is a critical step in the comprehensive management of heart failure, particularly in rheumatologic patients on biologic disease-modifying antirheumatic drugs (DMARDs).

Recall the adverse effect profile of the identified biologic agent.

Adalimumab is a TNF-alpha inhibitor. TNF-alpha inhibitors are known to worsen latent left ventricular dysfunction or cause new-onset heart failure.

Understanding the toxicity profile of TNF-alpha inhibitors dictates the necessity of removing the offending agent.

Formulate the comprehensive next best step in management.

Management includes diuresis with intravenous furosemide for the acute volume overload and immediate discontinuation of adalimumab.

Treating the symptoms without addressing the underlying pharmacologic trigger would result in continued myocardial toxicity and recurrent heart failure.

Key Concept

Tumor necrosis factor-alpha (TNF-alpha) inhibitors (e.g., adalimumab, infliximab, etanercept) can cause new-onset heart failure or exacerbate underlying cardiac dysfunction. Patients presenting with heart failure while on these agents must have the medication discontinued.

Estimated Time:2m 0s

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