每日一题_2022.08.21

A 63-year-old man with a history of liver cirrhosis secondary to hepatitis C and alcohol abuse is admitted to the ICU with profound hypotension. He had been evaluated in the emergency department after having worsening abdominal pain and fever for the past three days. He is in severe respiratory distress and is intubated. Blood pressure is 80/40 mm Hg despite adequate fluid resuscitation. He is started on vasopressors after placement of a central venous Line. Spontaneous bacterial peritonitis (SBP) is suspected, and a diagnostic paracentesis is performed and peritoneal fluid sent for analysis.

Which of the following statements is true?

A. Renal failure is not an independent predictor of mortality in patients with SBP.

B. The most common SBP organisms are Escherichia coli and Streptococcus pneumoniae.

C. A diagnosis of SBP can be confirmed by a white blood cell count of 400/μL, polymorphonuclear leukocytes of 80% and red blood cell count of 2,000 μL.

D. Blood cultures are not needed in a patient with SBP.

E. Fresh frozen plasma should be given for an INR of 1.7, to avoid hemorrhagic complications of a diagnostic paracentesis.

答案解析：

细菌移位是 SBP 的关键机制。自发性细菌性腹膜炎的诊断是通过腹水中存在超过250个/mm3多形核白细胞 (PMN)。然而，必须校正该计数是否存在红细胞 (RBC)，如果患者进行创伤性穿刺术，其水平通常升高。校正因子为每250个 RBC/mm3 血液减少1个PMN。涉及的最常见微生物是大肠埃希菌和克雷伯菌属。应进行腹水和血培养，因为50%的 SBP 病例与菌血症相关。在获得敏感性之前，需要使用广谱抗生素。头孢噻肟的感染率最高，副作用极小。重症患者可能需要进行穿刺术；使用超声和经验丰富的术者可降低患者风险。一项1100例患者的前瞻性研究显示，INR为1.7时不应需要校正以安全进行穿刺术。肾衰竭仍然是 SBP 患者死亡率的独立预测因素。

正确答案：C