A 55-year-old man comes to the office due to progressive abdominal distension for the past 2 months. He reports that his abdomen has become so large that his clothes no longer fit. Temperature is 37.5 C (99.5 F), blood pressure is 152/87 mm Hg, pulse is 80/min, and respirations are 18/min. The abdomen is grossly enlarged and nontender. Shifting dullness is present. Trace pitting edema is identified in the bilateral lower extremities. Paracentesis reveals bloody ascitic fluid. Repeat paracentesis from another site yields similar bloody fluid. Which of the following is most likely responsible for this patient's presentation?
This patient has new-onset ascites (abdominal distension, shifting dullness) that is persistently bloody on multiple paracenteses. Bloody ascites is caused by red blood cells leaking into the intraperitoneal fluid; ascites appears frankly bloody when the peritoneal red blood cell count is >50,000 mm3. Most cases occur due to localized trauma from a paracentesis; however, these bleeds usually resolve without intervention. Persistently bloody ascites found on multiple paracenteses suggests an underlying malignancy.
Hepatocellular carcinoma (HCC) is the most common malignancy to present with bloody ascites due to tumor growth disrupting and eroding nearby blood vessels. Less frequently, peritoneal metastases from distant primary sites (eg, ovaries, prostate) can cause bloody ascites. Therefore, patients with bloody ascites should undergo abdominal imaging, measurement of alpha-fetoprotein blood levels (elevated with HCC), and cytologic analysis of the ascitic fluid to identify the primary tumor. Unless the patient is hemodynamically compromised, no specific acute intervention is otherwise required for nontraumatic bloody ascites; in the rare case of hemodynamic compromise, angiography with embolization should be considered.
(Choice B) Nephrotic syndrome can result in ascites in association with diffuse anasarca. It typically causes non-bloody straw-yellow ascites, and most patients also have severe lower extremity edema. This patient's trace pitting edema may be related to ascites and underlying cirrhosis (eg, hypoalbuminemia) but is unlikely to reflect nephrotic syndrome.
(Choice C) Portal vein thrombosis does not commonly cause ascites because the obstruction occurs proximal to the hepatic sinusoids. Hepatic vein thrombosis (ie, Budd-Chiari syndrome) can cause ascites; however, it typically causes acute onset of non-bloody, straw-yellow ascites in association with fever and abdominal pain.
(Choice D) Spontaneous bacterial peritonitis typically causes fever, abdominal pain, and/or altered mental status associated with cloudy or turbid ascitic fluid. A formal diagnosis requires an increase in ascitic fluid polymorphonuclear cells (≥250 cells/mm3).
(Choice E) Abdominal tuberculosis can lead to ascites, but the fluid is generally straw-colored; bloody ascites is rare. In addition, tuberculous ascites is typically associated with abdominal pain as well as fever and night sweats, reflecting tuberculosis reactivation.
Educational objective:
Persistently bloody ascites after multiple diagnostic paracenteses is concerning for an underlying malignancy. Hepatocellular carcinoma is the most common cause, although bloody ascites can also occur with peritoneal metastases from distant primary sites (eg, ovaries, prostate). Cytologic analysis of the ascitic fluid can help identify the primary tumor.