Spontaneous Bacterial Peritonitis: A Rare Complication of Pulmonary Arterial Hypertension

Abstract

Approximately 3% of all diagnosed cases of ascites are of cardiac etiology. Although more commonly associated with heart failure, pulmonary arterial hypertension is a known but rare cause of cardiac ascites, which has not been associated with spontaneous bacterial peritonitis. We present a case of a 75-year-old male with known pulmonary arterial hypertension and new-onset ascites, the fluid analysis of which was consistent with both cardiac ascites and spontaneous bacterial peritonitis. He was successfully managed with antibiotics, loop diuretics, and mineralocorticoid receptor antagonists.

Keywords: echocardiography; pulmonary circulation; pulmonary hypertension; right ventricle; right-sided catheterization.

Figure 1

Liver ultrasound in right long axis demonstrating nodular contours with coarsened echotexture. Moderate volume ascites can also be seen.

Figure 2

Transthoracic echocardiogram in apical four-chamber view showing severe right atrial and ventricular enlargement, as well as flattened interventricular septum, consistent with elevated RV pressure and volume overload.

Figure 3

Transthoracic echocardiogram in apical four-chamber view showing moderate tricuspid regurgitation with a maximum velocity of 385 cm/second and max pressure gradient of 59.3 mmHg.

Figure 4

Diagnostic pathway in ascitic fluid analysis: SAAG can be used to differentiate between portal and non-portal hypertension etiologies of ascites. A low SAAG (<1.1) indicates ascites due to non-portal hypertension while an elevated SAAG (≥1.1) favors elevated portal hypertension. Ascitic protein can further help subdivide portal hypertension causes of ascites, where an elevated ascitic protein (≥2.5) indicates cardiac and post-hepatic ascites, whereas a low ascites protein (<2.5) favors cirrhosis.