Pylephlebitis: A Systematic Review on Etiology, Diagnosis, and Treatment of Infective Portal Vein Thrombosis

Abstract

Pylephlebitis, defined as infective thrombophlebitis of the portal vein, is a rare condition with an incidence of 0.37–2.7 cases per 100,000 person-years, which can virtually complicate any intra-abdominal or pelvic infections that develop within areas drained by the portal venous circulation. The current systematic review aimed to investigate the etiology behind pylephlebitis in terms of pathogens involved and causative infective processes, and to report the most common symptoms at clinical presentation. We included 220 individuals derived from published cases between 1971 and 2022. Of these, 155 (70.5%) were male with a median age of 50 years. There were 27 (12.3%) patients under 18 years of age, 6 (2.7%) individuals younger than one year, and the youngest reported case was only 20 days old. The most frequently reported symptoms on admission were fever (75.5%) and abdominal pain (66.4%), with diverticulitis (26.5%) and acute appendicitis (22%) being the two most common causes. Pylephlebitis was caused by a single pathogen in 94 (42.8%) cases and polymicrobial in 60 (27.2%) cases. However, the responsible pathogen was not identified or not reported in 30% of the included patients. The most frequently isolated bacteria were Escherichia coli (25%), Bacteroides spp. (17%), and Streptococcus spp. (15%). The treatment of pylephlebitis consists initially of broad-spectrum antibiotics that should be tailored upon bacterial identification and continued for at least four to six weeks after symptom presentation. There is no recommendation for prescribing anticoagulants to all patients with pylephlebitis. However, they should be administered in patients with thrombosis progression on repeat imaging or persistent fever despite proper antibiotic therapy to increase the rates of thrombus resolution or decrease the overall mortality, which is approximately 14%.

Septic thrombophlebitis of portal and splenic vein secondary to Fusobacterium nucleatum: A case report of an abdominal variant of lemierre syndrome

“…Lastly, fever and abdominal pain were the most common symptoms at admission similar to the presentation in this case. [3] Fusobacterium, commonly found as a commensal in oral cavity, gut and female genital tract, possess a myriad of virulence factors responsible for the development of necrotic abscess, septic thrombophlebitis, and thrombosis. For example, bacterial hemolysins lyse the erythrocytes, reducing oxygen transport to the site of infection and creating a favorable anaerobic environment for its growth.…”

“…Pylephlebitis commonly presents as an infective suppurative thrombosis of portal vein secondary to intra-abdominal or pelvic infection that is drained by the portal venous system. [3] Portal vein, formed from the confluence of superior mesenteric and splenic vein, drains blood from the spleen, gallbladder, pancreas and gastrointestinal tract (except lower rectum) to the liver. [6] Diverticulitis (26.5%) and appendicitis (22%) are therefore, the 2 most common causes of pylephlebitis followed by pylephlebitis due to unknown cause (11.5%) and that following liver abscess (8.5%), gastroenteritis (6.5%), surgery (6%), pancreatitis (5.5%), inflammatory bowel disease (4%) and others.…”

“…[2] Its incidence rate is reported to be approximately 0.37 to 2.7 cases per 100,000 person years. [3] Endothelial injury, venous stasis and hypercoagulability secondary to inherited or acquired thrombophilic disorders, cirrhosis, myeloproliferative disorders, intra-abdominal inflammatory conditions, abdominal surgery or trauma, malignancy, etc, predispose to the development of portal vein thrombosis. [4] Here, we present a case of infective suppurative pylephlebitis of portal vein and splenic vein with Fusobacterium nucleatum isolated on blood culture in a middle-aged female patient presenting with abdominal discomfort and fever.…”

Acute Appendicitis Complicated by Septic Thrombophlebitis of the Portal Vein Shown by 18F-FDG and 68Ga-FAPI-46 PET/CT

“…[1][2][3] Early diagnosis is difficult, due to nonspecific symptoms and signs, and limitations of diagnostic modalities. [4][5][6] Previous studies have suggested 18 F-FDG PET/CT is a useful technique to diagnose this infectious condition. 7,8 In this case, 68 Ga-FAPI-46 PET/CT showed higher radiotracer uptake than 18 F-FDG in the intense inflammatory process in pylephlebitis, resulting in larger disease extent.…”

“…Septic thrombophlebitis of the portal vein is a scarce and serious intra-abdominal infection or inflammation involving all segments of the gastrointestinal tract 1–3 . Early diagnosis is difficult, due to nonspecific symptoms and signs, and limitations of diagnostic modalities 4–6 . Previous studies have suggested 18 F-FDG PET/CT is a useful technique to diagnose this infectious condition 7,8 .…”