rainlove

作者：Kristina Rebelo  
出處：WebMD醫學新聞

　　November 18, 2009（加州聖地牙哥訊）－ 據估計，30%到80%肝硬化病患有以神經認知及精神運動缺失表現的神經精神功能失調，稱為微小肝性腦病變（minimal hepatic encephalopathy，MHE）。一項發表於美國腸胃科醫學會2009年年會的隨機分派研究綜合分析（Meta-analysis）結果顯示，益生菌可能成為這些病患的第一線治療。
　　
　　主要研究者、水牛城紐約州立大學內科住院醫師Sandhya Shukla在發表會後的訪談中向Medscape腸胃醫學表示，一般認為腸胃道產生的氨在MHE的病理生成上扮演關鍵角色，因為生病的肝臟清除毒性物質功能衰竭，類似肝性腦病變。
　　
　　目前急迫需要診斷與治療MHE。她指出，臨床上，當你進行複雜的神經運動檢查時，MHE不一定會表現出來，但這些狀況會變得明顯。MHE在肝硬化病患中很常見。
　　
　　【社會擔憂】
　　Shukla醫師表示，這些患者因為駕駛技巧不好以及有發生車禍的高風險，而成為最大的社會擔憂，這在今年較早時於Medscape腸胃醫學觀點中報告。過去的研究曾評估益生菌短期使用於少數MHE病患的效果；然而，這是第一個以系統性回顧來評估益生菌的角色，以及確實達成益生菌能逆轉MHE的特徵。
　　
　　她的團隊搜尋Medline、EMBASE以及Cochrane控制組試驗註冊資料庫，來評估益生菌治療的價值。
　　
　　搜尋到的56項隨機分派研究中，有3項符合納入條件；這些研究收納140位罹患MHE患者，病患被隨機分派接受益生菌（共78位）或安慰劑（共76位），平均時間為4.2個月。
　　
　　Shukla醫師報告，以益生菌治療與整體風險下降0.54（95%信賴區間為0.423-0.70；P<0.0001）有關。症狀減少與血清氨濃度顯著下降有關，標準化平均差異為-3.21（95%信賴區間為-6.15~-0.26）。
　　
　　使用益生菌與靜脈血清氨濃度顯著下降有關。根據Shukla醫師與其同事們表示，益生菌將改變腸胃道細菌，以非致病性、非產尿素酶乳酸菌取代致病性產尿素酶菌種。
　　
　　Shukla醫師提醒，由於病患族群的差異性，應小心闡釋這些研究結果。另一項試驗限制是，即使在肝臟醫學專家之間，也沒有標準的MHE定義。
　　
　　Shukla醫師表示，未來的研究將會包括足夠統計力量的隨機分派研究、試驗時間較長，以進一步了解益生菌對於MHE病程的長期效應。
　　
　　【每個人都有些擔心】
　　俄亥俄州克里夫蘭診所腸胃部門肝（肝臟）醫學中心主任William D. Carey醫師參加壁報發表但未參與這項研究，他向Medscape腸胃醫學表示，MHE對病患和社會有許多影響，這些人有駕駛上的風險，而且他們比較容易被傳喚和發生意外。
　　
　　他附帶表示，我認為MHE的處理在肝臟學是非常新興的領域，無疑地，照護病患的一般醫師們可能未被告知這個疾病。每個人都對律師會說醫師們將這些病患報告給掌管車輛相關部門有很大的責任而感到緊張。
　　
　　Carey醫師表示，目前為止，他並未對MHE病患使用益生菌，但他想要這麼做。問題是，目前並沒有此類治療將能降低駕駛失誤與車禍或是因此上法庭的數據；這將是未來研究一塊極具潛力的領域。
　　
　　Shukla醫師與她的同事們以及Carey醫師表示已無相關資金上的往來。


Probiotics Alleviate Symptoms of Minimal Hepatic Encephalopathy

By Kristina Rebelo
Medscape Medical News

November 18, 2009 (San Diego, California) — Estimates indicate that between 30% and 80% of patients with cirrhosis have a neuropsychiatric dysfunction that manifests as neurocognitive and psychomotor deficits, known as minimal hepatic encephalopathy (MHE). Results of a meta-analysis of randomized controlled trials presented here at the American College of Gastroenterology 2009 Annual Scientific Meeting indicate that probiotics have the potential to become first-line therapy for this patient population.

It is believed that gut-produced ammonia plays a key role in the pathogenesis of MHE because of the failure of the diseased liver to clear toxic products, similar to hepatic encephalopathy, lead investigator Sandhya Shukla, MD, internal medicine resident, State University of New York, Buffalo, told Medscape Gastroenterology in an interview during her poster presentation

"There is an urgent need to diagnose and treat MHE. Even though clinically, MHE doesn't manifest, when you do the complex psychomotor tests, the condition becomes obvious," she said. "MHE is epidemic in cirrhotic patients."

Societal Concerns

Dr. Shukla said that the gravest societal concerns are the poor driving skills and higher risk of automobile accidents and citations within this group, a subject reported on by Medscape Gastroenterology Viewpoints earlier this year. Prior work has been done in the area of evaluating probiotics in MHE in a small number of patients with short treatment duration; however, this is the first study to perform a systematic review to evaluate the role of probiotics and actually reach the conclusion that probiotics can reverse the characteristics of MHE, Dr. Shukla noted.

Her team searched Medline, EMBASE, and the Cochrane Controlled Trials Register to assess the value of probiotic therapy.

Among 56 randomized controlled trials found in the search, 3 fit the inclusion criteria; they involved 140 patients with MHE who were randomly assigned to receive either probiotics (n = 78) or placebo (n = 76) for a mean duration of 4.2 months.

Dr. Shukla reported that treatment with probiotics was associated with an overall risk reduction of 0.54 (95% confidence interval, 0.423 – 0.70; P < .0001).Symptom reduction correlated with a significant reduction in serum ammonia levels, with a standardized mean difference of ?3.21 (95% confidence interval, ?6.15 to ?0.26).

There was a significant reduction in venous ammonia levels with the use of probiotics. Probiotics will alter the gut flora, according to Dr. Shukla and colleagues, replacing the pathogenic urease-producing species with nonpathogenic, non-urease-producing lactobacilli.

Dr. Shukla warned that because of the heterogeneity of the patients, results should be interpreted with a modicum of caution. She said another study limitation was that even among hepatologists, there was no standard definition of MHE.

Future studies, Dr. Shukla said, will include an adequately powered randomized controlled trial conducted over a longer duration to better understand the long-term effects of probiotics on the course of MHE.

Everybody Is a Little Nervous

William D. Carey, MD, director of the Hepatology (Liver) Center in the Department of Gastroenterology at the Cleveland Clinic in Ohio, who attended the poster presentation but was not affiliated with the study, told Medscape Gastroenterology that MHE has many social implications for the patient and for the community. "These people pose a risk for driving," he said, "and they have more citations and accidents."

He added, "I think [management of MHE] this is a very emerging field within hepatology, and certainly the general physicians taking care of patients are probably underinformed about this. Everybody is a little nervous about what the lawyer will say about the risk to physicians having a higher responsibility to report patients to the motor vehicle department."

Dr. Carey said that to date, he has not put his MHE patients on probiotics, but he is tempted to do so. "The question is, there's no data yet that such therapy would reduce driving errors and motor vehicle accidents or citations. That's a fertile area for further research."

Dr. Shukla and her colleagues and Dr. Carey have disclosed no relevant financial relationships.

American College of Gastroenterology 2009 Annual Scientific Meeting: Abstract 191. Presented October. 25, 2009.