門靜脈炎於現今台灣之臨床表現 -單一醫學中心之經驗

Abstract

門靜脈炎(Pylephlebitis),特指發生於門靜脈系統的血栓性靜脈炎,為一腹腔內感染造 成之罕見且高致命性的併發症。門靜脈炎致病的機轉一般可分為兩類型:一是沿著門 靜脈血液回流而形成的順行性感染。另一則為門靜脈周圍的組織器官感染,致使致病 菌藉此蔓延至附近的門靜脈系統造成門靜脈的發炎。因為門靜脈炎是一個腹腔內感染 少見的併發症,此疾病實際的發生率目前仍難以評估。在西方的文獻中,憩室炎及盲 腸炎是最常造成門靜脈炎的原因,門靜脈炎的致死率約為三到五成。

根據研究,門靜脈炎好發於中年人,以男性居多; 約有八成的患者其初期的表現為腹 痛和發燒,但仍有部分患者因初期表徵欠缺特異性,以至於延誤了腹腔內感染合併門 靜脈炎的診斷。大部份門靜脈炎患者的細菌血液培養結果是革蘭氏陰性的嗜氧及厭氧 菌,因此在血液培養結果尚未出爐前,給予經驗性的廣效型抗生素療法是被建議的。 根據文獻報導,發生血栓性靜脈炎的門靜脈僅有極低的機會,約 0 到 16.7 %,能夠自 行打通,截至目前為止,對於門靜脈炎的患者是否需要合併使用抗血栓凝集藥物,仍 有爭議。

鑑於門靜脈炎的罕見性,多數的西方文獻報導僅侷限於單一或少數個案的集結,鮮少 有系統性的回顧及分析,本文的主旨在於回溯性收集台大醫院急診部於 2002 至2011 年間經電腦斷層影像診斷罹患門靜脈炎的患者,藉著分析其致病原因、病程表現及預 後,以及與西方文獻報導間的異同,以期能對日後門靜脈炎患者的治療能提供更本土 化的依據。

相同於之前的文獻報導:門靜脈炎好發于男性。被延遲診斷的腹腔內感染患者較容易 併發門靜脈炎。

但不同於之前西方文獻所記載的,在本院急診的族群裡,造成門靜脈炎的主要致病因並非腸胃道感染,而是肝臟膿瘍,尤其以克雷伯氏肺炎桿菌引起的肝臟膿瘍為大宗。 而且克雷伯氏肺炎桿菌感染是本院急診門靜脈炎族群中最常見的單一致病菌種,這種現 象可能肇因於目前克雷伯氏肺炎桿菌感染已躍升為台灣獨特的地區型(endemic)感 染因。是故,在血液細菌培養結果尚未出爐前,使用能涵蓋治療克雷伯氏肺炎桿菌的 抗生素是一件合理的選擇。

雖然在本實驗中,門靜脈炎的患者並沒有產生死亡案例,但即使是醫療環境進步如現 在,罹患門靜脈炎的患者仍有較高的比例有較長的住院時間、較易轉入加護病房以及 較易合併院內感染的情況發生,似乎也表示門靜脈炎的患者雖然在完整先進的醫療下 已不容易產生死亡個案,但腹腔內感染合併門靜脈炎的患者確實有較複雜的住院過 程。是故,在病患剛被診斷為門靜脈炎時,就可以事先告知病患及其家屬,以避免因 過度的醫療期待,造成無謂的醫療糾紛。

作者希望能藉由此單一醫院之回溯性研究,提醒台灣地區的醫療人員:門靜脈炎在台 灣不僅存在有不同於西方的致病因與菌種,也同樣擁有較多變及複雜的住院過程,是故,在處理此類患者時,應多加小心與留意。

Pylephlebitis is a septic thrombophlebitis of the portal venous system caused either by ascending infection from draining tissues of the portal venous system or by contagious infection from nearby organs. It is a rare complication of intra-abdominal infection; yet, the true incidence is difficult to evaluate. The mortality of pylephlebitis is high. Diverticulitis and appendicitis were major causes of pylephlebitis in the Western literature. However, in one-third of patients, the cause of pylephlebitis still remains obscured. According to literature review, pylephlebitis primarily occurs in middle-aged males. About 80 % of patients have an initial presentation of abdominal pain and fever, but the symptoms and signs may be nonspecific, resulting in delayed diagnosis. Positive blood cultures have been reported in 23–88 % of cases, most commonly Gram- negative aerobes and anaerobes, for which empirical broad-spectrum antibiotics are recommended. The rate of spontaneous recanalization after acute portal thrombosis, though not well established, seems extremely low (ranging from 0 to 16.7 %). So far, the efficacy of anticoagulants for this indication remains controversial. We retrospectively studied the etiology, clinical manifestation, and outcome by reviewing the medical records of all imaging-confirmed pylephlebitis cases diagnosed during the period 2002–2011 in the Emergency Department of National Taiwan university hospital. In this study, we aimed to conduct a retrospective clinical study on the recent trend of etiology, clinical manifestation, and prognosis of pylephlebitis, to see if it has distinct behavior in Taiwan from the Western country. Like prior literature review, our results reveal that, male patients and those who are delayed in diagnosing intra-abdominal infection are more likely to have pylephlebitis. Unlike prior literature review, in our study, the major cause of pylephlebitis is not gastrointestinal infection but liver abscess, especially liver abscess causes by Klebsiella pneumoniae infection. Mono- microbial K. pneumoniae was the most common pathogen of pylephlebitis in the present study, which might be related to a well-established unique endemic K. pneumoniae infection in Taiwan. Therefore, we recommended that initial empiric antibiotic treatment for pylephlebitis should cover K. pneumoniae in this region. Even though, there is no mortality case in our study. Patients with pylephlebitis are more likely to have longer hospital stays, more likely to be transferred to intensive care unit and more likely to complicate with in-hospital infection. Therefore, it might indicate that, even in the modern medical era, patients with pylephlebitis face more complicated clinical situations and outcomes. Therefore, when facing patients with pylephlebitis in Taiwan, it is important to remember its distinct microbial data. Also, it is practical to inform the patient and his/her family about the less favorable outcome of pylephlebitis.