WordNet

a pattern of symptoms indicative of some disease
a complex of concurrent things; "every word has a syndrome of meanings"

PrepTutorEJDIC

(疾患の徴候となる一群の)症徴候,症候群 / (事件・社会的状態などのパターンを示す)徴候形態

Wikipedia preview

出典(authority):フリー百科事典『ウィキペディア（Wikipedia）』「2014/06/06 22:46:52」(JST)

wiki en

In medicine, hepatopulmonary syndrome is a syndrome of shortness of breath and hypoxemia (low oxygen levels in the blood of the arteries) caused by vasodilation (broadening of the blood vessels) in the lungs of patients with liver disease. Dyspnea and hypoxemia are worse in the upright position (which is called platypnea and orthodeoxia, respectively).

Pathophysiology

The hepatopulmonary syndrome results from the formation of microscopic intrapulmonary arteriovenous dilatations in patients with both chronic and acute liver failure. The mechanism is unknown but is thought to be due to increased hepatic production or decreased hepatic clearance of vasodilators, possibly involving nitric oxide.^[1]

The vascular dilatations cause overperfusion relative to ventilation, leading to ventilation-perfusion mismatch and hypoxemia. There is an increased gradient between the partial pressure of oxygen in the pulmonary alveoli and adjacent arteries (alveolar-arterial [A-a] gradient) while breathing room air. Additionally, late in cirrhosis, it is common to develop high output failure, which would lead to less time in capillaries per red blood cell, exacerbating the hypoxemia.

Diagnosis

The hepatopulmonary syndrome is suspected in any patient with known liver disease who reports dyspnea (particularly platypnea). Patients with clinically significant symptoms should undergo pulse oximetry. If the syndrome is advanced, arterial blood gasses should be measured on air.^{[citation needed]}

A useful diagnostic test is contrast echocardiography. Intravenous microbubbles (> 10 micrometers in diameter) from agitated normal saline that are normally obstructed by pulmonary capillaries (normally <8 to 15 micrometers) rapidly transit the lung and appear in the left atrium of the heart within 7 heart beats. Similarly, intravenous technetium-99m–labeled albumin may transit the lungs and appear in the kidney and brain. Pulmonary angiography may reveal diffusely fine or blotchy vascular configuration. The distinction has to be made with an intracardiac right-to-left shunt.^{[citation needed]}

Treatment

Currently the only definitive treatment is liver transplantation.^[2] Alternative treatments such as supplemental oxygen or somatostatin to inhibit vasodilation remain anecdotal.

Prognosis

With liver transplantation, the 5 year survival rate is 76%, which is comparable to patients who undergo liver transplants who do not suffer from hepatopulmonary syndrome.^[3]

References

^ Rodríguez-Roisin, MD, Roberto. "Hepatopulmonary Syndrome — A Liver-Induced Lung Vascular Disorder". New England Journal of Medicine. Retrieved 2 March 2011.
^ Rodriguez-Roisin, R; Krowka MJ (Rodriguez-Roisin R, Krowka MJ. Is severe arterial hypoxaemia due to hepatic disease an indication for liver transplantation? A new therapeutic approach. Eur Respir J 1994;7:839-842). "Is severe arterial hypoxaemia due to hepatic disease an indication for liver transplantation?". European Respiratory Journal 7 (5): 839–842. PMID 8050537. Retrieved 2 March 2011. Check date values in: |date= (help)
^ Swanson, KL; Swanson KL, Wiesner RH, Krowka MJ. Natural history of hepatopulmonary syndrome: impact of liver transplantation. Hepatology 2005;41:1122-1129 (12 April 2005). "Natural history of hepatopulmonary syndrome: impact of liver transplantation". Hepatology 41 (5): Swanson KL, Wiesner RH, Krowka MJ. Natural history of hepatopulmonary syndrome: impact of liver transplantation. Hepatology 2005;41:1122–1129. doi:10.1002/hep.20658. PMID 15828054. Cite uses deprecated parameters (help)

UpToDate Contents

全文を閲覧するには購読必要です。 To read the full text you will need to subscribe.

1. 肝肺症候群：有病割合、原因、臨床症状、および診断 hepatopulmonary syndrome prevalence causes clinical manifestations and diagnosis
2. 肝肺症候群：自然経過、治療、および転帰 hepatopulmonary syndrome natural history treatment and outcomes
3. 嚢胞性線維症：肝胆道系疾患 cystic fibrosis hepatobiliary disease
4. 成人における肝硬変：合併症、全般的マネージメント、および予後の概要 cirrhosis in adults overview of complications general management and prognosis
5. 門脈肺高血圧症 portopulmonary hypertension

English Journal

Pulmonary function-morphologic relationships assessed by SPECT-CT fusion images.

Suga K.SourceDepartment of Radiology, St. Hill Hospital, 3-7-18 Imamura-Kita, Ube, Yamaguchi, 755-0151, Japan, sugar@sthill-hp.or.jp.
Annals of nuclear medicine.Ann Nucl Med.2012 Feb 18. [Epub ahead of print]
Pulmonary single photon emission computed tomography-computed tomography (SPECT-CT) fusion images provide objective and comprehensive assessment of pulmonary function and morphology relationships at cross-sectional lungs. This article reviewed the noteworthy findings of lung pathophysiology in wide-
PMID 22350957

Elevated levels of endothelin-1 in hepatic venous blood are associated with intrapulmonary vasodilatation in humans.

Koch DG, Bogatkevich G, Ramshesh V, Lemasters JJ, Uflacker R, Reuben A.SourceDivision of Gastroenterology and Hepatology, Department of Medicine, Medical University of South Carolina, ART 7100A, 25 Courtenay Dr. MSC 290, Charleston, SC 29425, USA. kochd@musc.edu
Digestive diseases and sciences.Dig Dis Sci.2012 Feb;57(2):516-23. Epub 2011 Oct 1.
BACKGROUND: Hepatopulmonary syndrome is a pulmonary vascular complication of cirrhosis in which intrapulmonary vasodilatation (IPV) results in hypoxemia. Endothelin-1 (ET-1), produced by proliferating cholangiocytes, has been identified as a mediator of IPV in an animal model of HPS, but the pathoph
PMID 21964742