A 59-year-old man with a known history of alcohol-related cirrhosis is brought to the emer… — USMLE Step 2 CK

A 59-year-old man with a known history of alcohol-related cirrhosis is brought to the emergency department by his family due to increasing confusion, lethargy, and diffuse abdominal discomfort over the past $48$ hours. His home medications include nadolol, spironolactone, and furosemide. His temperature is $37.8^\circ\text{C}$ ( $100.0^\circ\text{F}$ ), pulse is $92/\text{min}$ , blood pressure is $105/65\text{ mmHg}$ , and respirations are $16/\text{min}$ . Physical examination reveals scleral icterus and spider angiomas. The abdomen is distended with shifting dullness and diffuse, mild tenderness to palpation without rebound or guarding. Asterixis is present on neurologic examination.

Laboratory studies show the following:

Test	Result
Total bilirubin	$3.2\text{ mg/dL}$
Albumin	$2.6\text{ g/dL}$
INR	$1.6$
Creatinine	$1.2\text{ mg/dL}$

A diagnostic paracentesis is performed, and ascitic fluid analysis reveals a total protein of $1.1\text{ g/dL}$ and a leukocyte count of $650/\text{mm}^3$ with $75\%$ neutrophils.

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

Intravenous ceftriaxone and intravenous albuminCevap
B
Intravenous meropenem, vancomycin, and intravenous albumin
C
Intravenous fluids, oral lactulose, and oral rifaximin
D
Intravenous furosemide and oral spironolactone
E
Insertion of a nasogastric tube and abdominal radiography

Cevap

The most appropriate next step is the administration of intravenous ceftriaxone and intravenous albumin.

The correct management is administering intravenous ceftriaxone and intravenous albumin. The patient's clinical presentation of confusion, abdominal discomfort, and fever in the setting of cirrhosis strongly suggests Spontaneous Bacterial Peritonitis (SBP). The diagnosis is confirmed by an absolute neutrophil count (PMN) in the ascitic fluid of

487.5/\text{mm}^3

(calculated as

650/\text{mm}^3 \times 0.75

), which is above the diagnostic threshold of

250/\text{mm}^3

. The standard of care for community-acquired SBP is a third-generation cephalosporin, such as ceftriaxone or cefotaxime, to cover enteric Gram-negative bacteria. Furthermore, intravenous albumin is indicated to decrease the risk of hepatorenal syndrome and improve survival, particularly in patients with a serum creatinine

> 1.0\text{ mg/dL}

or total bilirubin

> 4.0\text{ mg/dL}

Adım Adım Çözüm

Calculate the absolute neutrophil (PMN) count in the ascitic fluid.

650 \times 0.75 = 487.5/\text{mm}^3

To determine if the patient meets the diagnostic criteria for Spontaneous Bacterial Peritonitis (PMN

\geq 250/\text{mm}^3

Identify the required antibiotic coverage for community-acquired SBP.

A third-generation cephalosporin (e.g., ceftriaxone or cefotaxime).

SBP is typically monomicrobial and most commonly caused by enteric Gram-negative organisms like E. coli and Klebsiella, which are well covered by third-generation cephalosporins.

Evaluate the need for adjunctive therapy.

Intravenous albumin is indicated.

Albumin expands intravascular volume to prevent hepatorenal syndrome, which is a major cause of mortality in SBP, particularly given the patient's elevated creatinine (

> 1.0\text{ mg/dL}

) and bilirubin.

Anahtar Kavram

Diagnosis and management of Spontaneous Bacterial Peritonitis (SBP) using ascitic fluid analysis, third-generation cephalosporins, and adjunctive intravenous albumin.

Soru

Cevap

Adım Adım Çözüm

Anahtar Kavram

Sık Yapılan Hatalar

Konular

Bu konudan daha fazla soru