Hepatopulmonary syndrome associated with schistosomal liver disease

CASE PRESENTATION A 55-year-old man known to have biopsy-proven hepatic fibrosis secondary to previously treated schistosoma mansonirelated liver disease. He presented in 1988 with hypersplenism for which he underwent splenectomy. In the summer of 1994 he developed dyspnea on minimal exertion, platypnea, dry cough and cyanosis upon standing. He was maintained on diuretics, and lactulose for increasing ascites and encephalopathy. Physical examination revealed a thin, afebrile man with stable hemodynamic status, jaundice, cyanosis with stigmata of chronic liver disease and marked digital clubbing. His chest had bilateral basal lung crackles. He had previous splenectomy and moderate ascites. Complete blood cell count was normal with hemoglobin of 130 g/L. Bilirubin was 98 mol/L (normal 0 to 17) and albumin was 11 g/L (38 to 50). Aspartate aminotransferase was 132 IU/L (normal 15 to 37), alanine aminotransferase 67 IU/L (30 to 65) and alkaline phosphates 243 IU/L (50 to 136). Hepatitis B and C serology was negative. Antinuclear antibody level was less than 40, and ceruloplasmin, iron studies and alpha 1 antitrypsin levels were normal. Endoscopic ret-

M Al-Moamary, I Altraif.Hepatopulmonary syndrome associated with schistosomal liver disease.Can J Gastroenterol 1997;11(5):449-450.A 55-year-old man with schistosomal liver disease presented with shortness of breath, orthodeoxia, platypnea, cyanosis, marked digital clubbing and liver failure.Extensive investigation revealed no other etiology for liver disease apart from schistosomiases.The diagnosis of hepatopulmonary syndrome was based on clinical grounds, as well as abnormal arterial blood gases and positive contrast echocardiography.The patient underwent orthotopic liver transplantation, which was initially successful, but then died of respiratory complications and multi-organ failure on day 42 post-transplant.To the authors' knowledge this is the first report of hepatopulmonary syndrome associated with schistosomal liver disease.
rograde cholangiopancreatography was consistent with cirrhosis, and the antimitochondrial antibody was negative.International normalized ratio was 2.8.grade II esophageal varices were documented by upper gastrointestinal endoscopy.Arterial blood gases (Table 1) revealed chronic respiratory alkalosis, hypoxemia, orthodeoxia and slight correction of hypoxemia on 100% inspired oxygen using a face mask technique.The estimated fraction of the intrapulmonary shunt from the nomogram was 35%.Chest x-ray was unremarkable.Forced expiratory volume in 1 s was 2.38 (66%), forced vital capacity 2.08 (71%) with a ratio of 87%, total lung capacity 4.01 (67%) and diffusion capacity 4.09 (48%), which was consistent with moderate diffusion impairment.
Echocardiogram documented the intrapulmonary shunt by positive microbubbles test (microbubbles were seen in the right ventricle after four to five beats).Swan-Ganz catheterization study showed normal right ventricle and pulmonary artery pressures (right atrial pressure 1 mmHg, right ventricle pressure 17/1 mmHg, pulmonary artery pressure 16/1 mmHg and pulmonary capillary wedge pressure 7 mmHg).
The patient underwent orthotropic liver transplantation because he was progressively symptomatic and had liver failure with worsening hypoxemia.The initial postliver transplant course showed gradual improvement in oxygenation.On the ninth post-transplantation day he was successfully extubated and maintained on 2 L/min oxygen with a saturation of 94% to 96%.
Eleven days after transplantation, bilateral lung infiltrates developed with shortness of breath and desaturation, for which he was reintubated.His sputum grew Actinobacter species and Klebsiella pneumoniae.Despite appropriate antibiotic coverage he continued to require a high fraction of inspired oxygen; for several days he was maintained on 100% oxygen.On day 42 post-liver transplant the patient died from severe hypoxemia, sepsis and multi-organ failure.

DISCUSSION
For the past four decades attention has focused on the association of oxygen desaturation with chronic liver disease.HPS was first suggested in 1977 by Kennedy and Knudson (3).It was proposed to be due to a remarkable dilation of the peripheral branches of the pulmonary vessels, reflecting a state of vasoparalysis to hypoxic stimuli.Direct arteriovenous communication has also been demonstrated (4,5).
Various liver diseases have been associated with this syndrome, and the presence of intrapulmonary shunt has been shown to occur in schistosomal cor pulmonale without liver failure (6).To our knowledge this is the first report of HPS associated with liver failure due to schistosomal liver disease without cor pulmonale.
Clinically the combination of platypnea, digital clubbing and spider angioma in the setting of chronic liver disease is suggestive of HPS.This should be supported by the presence of hypoxemia and orthodeoxia, a decrease of the partial arterial oxygen concentration by 10% upon standing (7).
It is essential to establish the diagnosis of HPS.For practical purposes, contrast enhanced echocardiogram appears to be the most sensitive diagnostic test to detect intrapulmonary vascular dilation. 99Tc microaggregated albumin scan and pulmonary angiography might be needed to confirm the diagnosis in certain cases (7)(8)(9).
The mechanism of HPS in schistosomal liver disease is probably not different from other etiologies of chronic liver dysfunction associated with HPS, but this is speculative because the mechanism of HPS is unknown.Until recently HPS was considered a contraindication for liver transplantation.However, the accumulated data have shown that HPS does not contraindicate surgery as long as intra-and postoperative oxygenation is maintained.Furthermore, severe hypoxemia has been proposed as an indication for liver transplantation (9).Krowka and Cortese (9) showed that 13 of 15 cases with HPS were transplanted successfully, and two of 15 cases had the procedure mainly for severe oxygen desaturation.This review showed resolution of hypoxemia in all but one patient who required arterial embolization.
In the case presented, severe hypoxemia was associated with HPS in a patient with schistosomal liver disease.This case demonstrates that schistosomiasis can be associated with HPS.
Can J Gastroenterol Vol 11 No 5 July/August 1997