Pyogenic Abscess after Hepatic Artery Embolization: A Rare but Potentially Lethal Complication

Hepatic artery embolization (HAE) is used commonly to treat liver tumors or hemorrhage. Infectious complications are rare but carry high rates of morbidity and mortality. Identification of clinical factors associated with postembolization abscess may improve management and outcome.Clinical and pathologic variables of patients treated with HAE were collected and analyzed to determine the etiology, incidence, and outcome of pyogenic hepatic abscess.From January 1998 to January 2010, 971 patients underwent 2,045 HAE procedures. Fourteen patients developed a pyogenic hepatic abscess after embolization, for an overall rate of 1.4%. Thirty-four patients (4%) had a history of bilioenteric anastomosis (BEA) and 21 patients (2%) lacked a competent sphincter of Oddi because of the presence of a biliary stent (n = 19) or a previous sphincterotomy (n = 2). Eleven of the 34 patients with a BEA (33%) and two of 21 patients with an incompetent sphincter (10%) developed abscesses, in contrast to only one abscess (0.05%) among the 916 patients with apparently normal sphincters (0.1%; odds ratio, 437.6; 95% CI, 54.2-3,533; P.0001). Gram-negative and Gram-positive aerobes were the most common bacteria isolated after drainage. Percutaneous drainage was the initial management strategy in all patients; two patients (14%) required subsequent surgical drainage and hepatectomy, and three (21%) died.Pyogenic hepatic abscess is rare after HAE. A history of BEA or an incompetent sphincter of Oddi caused by a biliary stent or previous sphincterotomy substantially increases the likelihood of this highly morbid and potentially fatal complication.