Protective effects of hydrogen sulfide on portal hypertensive vasculopathy in rabbits by activating AKT-NF-κB pathway

The role of hydrogen sulfide (H₂S) in portal hypertension (PH)-induced esophagus-gastric junction vascular lesions in rabbits was observed. The rabbit PH models were established. The animals were randomly divided into the following groups: normal, PH, PH+sodium hydrosulfide (PH+S), PH+propargylglycine (PH+PPG). The plasma H₂S levels, apoptosis of esophageal-gastric junction vascular smooth muscle cells, and the expression of nuclear transcription factor-κB (NF-κB), p-AKT, IκBa and Bcl-2 were detected. The cystathionine γ lyase (cystathionine-gamma-splitting enzyme, CSE) in the junction vascular tissue was measured. The results showed that the plasma H₂S levels and the CSE expression levels had statistically significant difference among different groups (P<0.05). As compared with PH group, plasma H₂S levels were declined obviously (11.9±4.2 vs. 20.6±4.5, P<0.05), and CSE expression levels in the junction vascular tissue were notably reduced (1.7±0.6 vs. 2.8±0.8, P<0.05), apoptosis rate of vascular smooth muscle cells per unit area was significantly decreased (0.10±0.15 vs. 0.24±0.07, P<0.05), and the expression levels of p-AKT and NF-κB were significantly decreased (2.31±0.33 vs. 3.04±0.38, P<0.05; 0.33±0.17 vs. 0.51±0.23, P<0.05), however, IκBa and Bcl-2 expression increased obviously (5.57±0.17 vs. 3.67±0.13, P<0.05; 0.79±0.29 vs. 0.44±0.36, P<0.05) in PH+PPG group. As compared with PH group, H₂S levels were notably increased (32.7±7.3 vs. 20.6±4.5, P<0.05), the CSE levels in the junction vascular tissue were significantly increased (6.3±0.7 vs. 2.8±0.8, P<0.05), apoptosis rate of vascular smooth muscle cells per unit area was significantly increased (0.35±0.14 vs. 0.24±0.07, P<0.05), and the expression levels of p-AKT and NF-κB were significantly increased (4.29±0.49 vs. 3.04±0.38, P<0.05; 0.77±0.27 vs. 0.51±0.23, P<0.05), yet IκBa and Bcl-2 expression decreased significantly (3.23±0.24 vs. 3.67±0.13, P<0.05; 0.31±0.23 vs. 0.48±0.34, P<0.05) in PH+S group. It is concluded that esophagus-gastric junction vascular lesions happen under PH, and apoptosis of smooth muscle cells is declined. H₂S can activate NF-κB by the p-AKT pathway, leading to the down-regulation of Bcl-2, eventually stimulating apoptosis of vascular smooth muscle cells, easing PH. H₂S/CSE system may play an important role in remission of PH via the AKT-NF-κB pathway.

Pulmonary shunts in severe hepatosplenic schistosomiasis: Diagnosis by contrast echocardiography and their relationship with abdominal ultrasound findings

Background

Schistosomiasis is endemic to several parts of the world. Among the species that affect humans, Schistosoma mansoni is one of the most common causes of illness. In regions where schistosomiasis mansoni is endemic, reinfection is responsible for the emergence of hepatosplenic schistosomiasis (HSS) with portal hypertension in about 10% of infected individuals. Regardless of its etiology, portal hypertension may bring about the formation of arteriovenous fistulas and pulmonary vascular dilation, thus constituting a pulmonary shunt and its presence has been associated with the occurrence of neurological complications. The objective of this study was to identify pulmonary shunt using TTCE in patients with HSS and esophageal varices, and to compare the abdominal ultrasound and endoscopy findings among patients with and without pulmonary shunt.

Methodology/Principal findings

In this case series, a total of 461 patients with schistosomiasis mansoni were prospectively evaluated using abdominal ultrasound and endoscopy and 71 presented with HSS with esophageal varices. Fifty seven patients remained in the final analysis. The mean age of the patients was 55 ± 14 years, and 65% were female. Pulmonary shunts were observed in 19 (33.3%) patients. On comparing the groups with and without pulmonary shunt, no significant differences were observed in relation to the abdominal ultrasound and endoscopic findings. When comparing the two subgroups with pulmonary shunts (grade 1 vs grades 2 and 3), it was observed that the subgroup with shunt grades 2 and 3 presented with a significantly higher frequency of an enlarged splenic vein diameter (>0.9 cm), and an advanced pattern of periportal hepatic fibrosis (P = 0.041 and P = 0.005, respectively). None of the patients with pulmonary shunts had severe neurological complications.

Conclusions/Significance

Our findings suggest that in HSS with esophageal varices the pulmonary shunts may be present in higher grades and that in this condition it was associated with ultrasound findings compatible with advanced HSS.

Among the species of Schistosoma that infect humans Schistosoma mansoni is one of the most common causes of illness. In the areas where schistosomiasis mansoni is endemic, around 10% of infected individuals develop hepatosplenic schistosomiasis (HSS) with portal hypertension. Portal hypertension may promotes an imbalance in the hepatic production of vasoactive substances, which may act on the lungs promoting the formation of arteriovenous fistulas and pulmonary vascular dilation, a condition that is called a pulmonary shunt. When the pulmonary shunt is of higher grades, small thrombus or septic emboli that would normally be filtered through the pulmonary capillaries reach the left heart and the systemic circulation, which can lead to neurological complications. We found pulmonary shunts in patients with HSS and esophageal varices and we also found that patients with higher grades of pulmonary shunts presented with a significantly higher frequency of advanced periportal fibrosis and an enlarged splenic vein diameter. No neurological complications were observed. Our findings suggest that pulmonary shunts may be present in patients with HSS and esophageal varices. The abdominal ultrasound findings compatible with advanced HSS could be used as screening to investigate pulmonary shunt.

Caput Medusae due to portal hypertension in schistosomiasis mansoni

A 62-year-old Brazilian man who lived in endemic areas of tropical diseases had an episode of hematemesis associated with portal hypertension. He used to swim in natural ponds during childhood and developed the hepatosplenic form of schistossomiasis with moderate ascites, in addition to the characteristic features of abdominal Caput Medusae. The aim of the report is highlight the role of chronic liver disease and schistossomiasis.

Radiofrequency ablation for treatment of hypersplenism: A feasible therapeutic option

We present a case of a patient with hypersplenism secondary to portal hypertension due to hepato-splenic schistosomiasis, which was accompanied by severe and refractory thrombocytopenia. We performed spleen ablation and measured the total spleen and ablated volumes with contrast-enhanced computed tomography and volumetry. No major complications occurred, thrombocytopenia was resolved, and platelet levels remained stable, which allowed for early treatment of the patient’s underlying disease. Previous work has shown that splenic radiofrequency ablation is an attractive alternative treatment for hypersplenism induced by liver cirrhosis. We aimed to contribute to the currently sparse literature evaluating the role of radiofrequency ablation (RFA) in the management of hypersplenism. We conclude that splenic RFA appears to be a viable and promising option for the treatment of hypersplenism.

Splenic artery ligature associated with endoscopic banding for schistosomal portal hypertension

AIM: To propose a less invasive surgical treatment for schistosomal portal hypertension.

METHODS: Ten consecutive patients with hepatosplenic schistosomiasis and portal hypertension with a history of upper gastrointestinal hemorrhage from esophageal varices rupture were evaluated in this study. Patients were subjected to a small supraumbilical laparotomy with the ligature of the splenic artery and left gastric vein. During the procedure, direct portal vein pressure before and after the ligatures was measured. Upper gastrointestinal endoscopy was performed at the 30^th postoperative day, when esophageal varices diameter were measured and band ligature performed. During follow-up, other endoscopic procedures were performed according to endoscopy findings.

RESULTS: There was no intra-operative mortality and all patients had confirmed histologic diagnoses of schistosomal portal hypertension. During the immediate postoperative period, two of the ten patients had complications, one characterized by a splenic infarction, and the other by an incision hematoma. Mean hospitalization time was 4.1 d (range: 2-7 d). Pre- and post-operative liver function tests did not show any significant changes. During endoscopy thirty days after surgery, a decrease in variceal diameters was observed in seven patients. During the follow-up period (57-72 mo), endoscopic therapy was performed and seven patients had their varices eradicated. Considering the late postoperative evaluation, nine patients had a decrease in variceal diameters. A mean of 3.9 endoscopic banding sessions were performed per patient. Two patients presented bleeding recurrence at the late postoperative period, which was controlled with endoscopic banding in one patient due to variceal rupture and presented as secondary to congestive gastropathy in the other patient. Both bleeding episodes were of minor degree with no hemodynamic consequences or need for blood transfusion.

CONCLUSION: Ligature of the splenic artery and left gastric vein with supraumbilical laparotomy is a promising and less invasive method for treating presinusoidal schistosomiasis portal hypertension.

Role of hydrogen sulfide in portal hypertension and esophagogastric junction vascular disease

AIM: To investigate the association between endogenous hydrogen sulfide (H₂S) and portal hypertension as well as its effect on vascular smooth muscle cells.

METHODS: Portal hypertension patients were categorized by Child-Pugh score based on bilirubin and albumin levels, prothrombin time, ascites and hepatic encephalopathy. Plasma H₂S concentrations and portal vein diameters (PVDs) were compared between portal hypertension patients and control participants, as well as between portal hypertension patients with varying degrees of severity. In addition, we established a rabbit hepatic schistosomiasis portal hypertension (SPH) model and analyzed liver morphology, fibrosis grade, plasma and liver tissue H₂S concentrations, as well as cystathionine γ-lyase (CSE) activity and phosphorylated extracellular signal-regulated kinase (pERK)1/2, B cell lymphoma (Bcl)-2 and Bcl-XL expression in portal vein smooth muscle cells, in addition to their H₂S-induced apoptosis rates.

RESULTS: In portal hypertension patients, endogenous H₂S levels were significantly lower than those in healthy controls. The more severe the disease was, the lower were the H₂S plasma levels, which were inversely correlated with PVD and Child-Pugh score. Liver tissue H₂S concentrations and CSE expression were significantly lower in the SPH rabbit livers compared with the control animals, starting at 3 wk, whereas pERK 1/2 expressions gradually increased 12-20 wk after SPH model establishment. In portal vein smooth muscle cells, increasing H₂S levels led to increased apoptosis, while Bcl-2 and Bcl-XL expression decreased.

CONCLUSION: H₂S prevents vascular restructuring caused by excessive proliferation of smooth muscle cells via apoptosis induction, which helps to maintain normal vascular structures.

[Postoperative complications of advanced schistosomiasis portal hypertension]

The data of 72 cases of advanced schistosomiasis portal hypertension patients who received surgical treatment were retrospectively analyzed in the Fifth People's Hospital of Changde City from January, 1999 to January, 2011. Postoperative complications occurred in 17 cases, and the rate was 23.6%, including intra-abdominal bleeding in 2 cases, postoperative infection in 5 cases, recent upper gastrointestinal bleeding in 3 cases, massive ascites in 2 cases, persistent fever in 3 cases, and unusual increase of platelets and portal vein thrombosis in 2 cases.

[Study on risk factors of early complications after surgery for schistosomal portal hypertension]

OBJECTIVE

To explore the related factors of early complications after surgery for schistosomal portal hypertension, so as to provide a scientific basis for prevention of postoperative complications and development of perioperative prevention programe.

METHODS

Case data of patients with schistosomal portal hypertension in Xiangyue Hospital affiliated to Hunan Institute of Parasitic Diseases from January, 2000 to September, 2009 were collected. With single factor analysis and relevant professional knowledge, related factors were analysed with logistic regression analysis.

RESULTS

A total of 52 related factors from the data of 323 cases were analysed with univariate analysis, indicating that 17 factors, including sex, history of bleeding, history of smoking, history of ascites, preoperative length of stay, diameter of portal vein, A/G ratio, albumin, total bilirubin, blood ammonia, total bile acid, operative mode, blood loss, blood transfusion, size of the right liver, postoperative analgesia, time of indwelling gastric tube, were related to the incidence of postoperative complications (all P values < 0.05). Logistic regression results showed the portal vein diameter, A/G ratio, bleeding history, blood loss, time of indwelling gastric tube were risk factors of postoperative complications within 30 days. Postoperative analgesia was considered as the protection factor.

CONCLUSIONS

The patients with larger portal vein diameter, lower of A/G ratio, history of bleeding, more loss of blood, longer retention with gastric tube have greater risk of postoperative complication. Loss of blood in operation was the greatest risk, but postoperative analgesia was the protection factor.

[Case report: Budd-Chiari syndrome and esophageal variceal bleeding due to alveolar echinococcosis]

Alveolar echinococcosis of the liver is a rare larval cestode disease which is due to the intrahepatic growth of the tapeworm Echinococcus multilocularis. This cestode naturally evolves as a larval stage within cysts in the body of carnivores. Humans are accidental intermediate hosts and become infected, either by eating food contaminated with carnivore-originated eggs or by touching foxes. It behaves as malignant liver tumour and rarely causes Budd-Chiari syndrome and variceal bleeding. Budd-Chiari syndrome is a hepatic venous outflow tract obstruction and may be present abdominal pain, hepatomegaly and ascites. Parasitic cysts may cause compression and thrombosis of the hepatic venous outflow tract. It may present as portal hypertension and variceal upper gastrointestinal bleeding. We here in report a 47-year-old woman without a prior history of liver disease presented with Budd-Chiari syndrome and variceal bleeding due to Alveolar echinococcosis. The course of this rare disease is demonstrated by means of the most important laboratory, serologic and radiologic parameters.

Pre- and postoperative systemic hemodynamic evaluation in patients subjected to esophagogastric devascularization plus splenectomy and distal splenorenal shunt: A comparative study in schistomomal portal hypertension

AIM: To investigate the systemic hemodynamic effects of two surgical procedures largely employed for treatment of schistosomal portal hypertension.

METHODS: Thirty-six patients undergoing elective surgical treatment of portal hypertension due to hepatosplenic mansonic schistosomiasis were prospectively evaluated. All patients were subjected to preoperative pulmonary artery catheterization; 17 were submitted to esophagogastric devascularization and splenectomy (EGDS) and 19 to distal splenorenal shunt (DSRS). The systemic hemodynamic assessment was repeated 4 d after the surgical procedure.

RESULTS: Preoperative evaluation revealed (mean ± SD) an increased cardiac index (4.78 ± 1.13 L/min per m²), associated with a reduction in systemic vascular resistance index (1457 ± 380.7 dynes.s/cm⁵.m²). The mean pulmonary artery pressure (18 ± 5.1 mmHg) as well as the right atrial pressure (7.9 ± 2.5 mmHg) were increased, while the pulmonary vascular resistance index (133 ± 62 dynes.s/cm⁵.m²) was decreased. Four days after EGDS, a significant reduction in cardiac index (3.80 ± 0.4 L/min per m², P < 0.001) and increase in systemic vascular resistance index (1901.4 ± 330.2 dynes.s/cm⁵.m², P < 0.001) toward normal levels were observed. There was also a significant reduction in pulmonary artery pressure (12.65 ± 4.7 mmHg, P < 0.001) and no significant changes in the pulmonary vascular resistance index (141.6 ± 102.9 dynes.s/cm⁵.m²). Four days after DSRS, a non-significant increase in cardiac index (5.2 ± 0.76 L/min per m²) and systemic vascular resistance index (1389 ± 311 dynes.s/cm⁵.m²) was observed. There was also a non-significant increase in pulmonary artery pressure (19.84 ± 5.2 mmHg), right cardiac work index (1.38 ± 0.4 kg.m/m²) and right ventricular systolic work index (16.3 ± 6.3 g.m/m²), without significant changes in the pulmonary vascular resistance index (139.7 ± 67.8 dynes.s/cm⁵.m²).

CONCLUSION: The hyperdynamic circulatory state observed in mansonic schistosomiasis was corrected by EGDS, but was maintained in patients who underwent DSRS. Similarly, the elevated mean pulmonary artery pressure was corrected after EGDS and maintained after DSRS. EGDS seems to be the most physiologic surgery for patients with schistosomal portal hypertension.

[Portal hypertension in mansonic schistosomiasis: repercussions of surgical treatment on the histomorphometric profile of the gastric mucosa]

The repercussions from surgical treatment for controlling portal hypertension and its effects on the gastric vasculature of young patients with mansonic schistosomiasis were investigated by digital image analysis. The study included five patients at the preoperative stage and 27 patients who had undergone surgical intervention at different times in the past: 0-2 years ago, n=4; 2-6 years ago, n=13, and more than 6 years ago, n=10. Endoscopic biopsies were taken from the mucosa of the gastric antrum and body endoscopic mucosa and the samples underwent routine histological tests after embedding in paraffin blocks. Histological thin sections were used for histomorphometric analysis of the following parameters: mean number of vessels per field, and mean diameter and thickness of the vessel walls. The results showed that, between the patients whose operation was not more than two years ago and those whose operation was more than six years ago, there was a significant decrease in the density and diameter of the vessels. These findings give support to the concept that the surgical treatment administered decreases specific histological alterations like hemorrhage and ectasia, over the long term.

[Place of surgery in the prevention of recurrences of digestive haemorrhages at the patients presenting a portal hypertension due to Schistosoma mekongi]

In spite of a decrease of the prevalence of hepato-splenic schistosomiasis thanks to mass-treatment with Praziquentel from December 1994 till now (CNM - MSF - WHO - Health Provincial Director) of target-populations in Kratie Province, severe cases of portal hypertension are not exceptional (digestive bleedings, after rupture of oesophageal varices). Out of 106 cases of portal hypertension: alI patients have had clinical survey biological tests (liver function, haematology and serology). Most of them had ultrasonography (Aloka 55,500 Sound 3.5 MHz). Nearly half of the group of 153 patients has never had bleedings. More than 45 were not eligible for surgery for different reasons: severe anaemia (few possibilities for massive transfusion in Cambodia), serology (S. mekongi) + but also hepatitis B or C +, hepatic biological exams (hepatic insufficiency). So we decided for eleven of them to use a surgical decompression procedure in order to decrease portal hypertension and the porto-systemic gradient. After defining portal hypertension, specific clinical features of portal hypertension (secondary to Schistosomiasis) the authors report eleven cases who were operated on (2000-2002): 4 mesenterico-cave shunt with interposition of a graft (Drapanas' procedure), 1 operation of HASSAB (after splenectomy), 6 proximal spleno-renal diversion (after splenectomy). After studying the results of the eleven patients, discussion with other surgical procedures, particularly endoscopic procedures is developed. The follow-up of these patients during at least five years is mandatory to give guidelines for post-systemic shunts to prevent rebleeding (near other methods). Treated too late, schistosomiasis has no benefit from drugs (Praziquentel). After a mean period of forty two months, the following results are: mortality: one case (10 days after operation): hepatic insufficiency (group Child B/C). morbidity: one occlusion of the small intestine, after 4 months (debridment), operated at the Provincial hospital of Kratie (case no1). Ten patients resume work, family and social life between Kratie and Sambor in 2002. No rebleeding. No encephalopathy.

[Histology of liver lesions due to Schistosoma mekongi. About six cases with severe portal hypertension operated in Cambodia]

Schistosomiasis mekongi was shown to be endemic, along the Mekong River, in northern Cambodia, affecting many patients with portal hypertension. Surgical procedures were proposed to some patients with digestive haemorrhage history to avoid fatal recurrence. The aim of our study was to evaluate the intensity of the liver fibrosis among these patients. During surgical treatment, liver biopsies were collected, fixed in Bouin or in formalin and processed at the Institut Pasteur of Cambodia. Sections were stained by H&E, Masson's trichrome, PAS, Ziehl-Neelsen's method and Congo Red. A total of six biopsies from patients aged 16-36 were analysed. There was complete disorganization of hepatic architecture with fibrous enlargement of portal tracts and some portal-portal bridging fibrosis, but there was no cirrhosis. In portal areas, there was blood vessel congestion and thrombosis with inflammation. Bile ducts were normal. In the parenchyma, congestion of sinusoidal capillaries was combined with focal mononuclear inflammatory infiltrate. There was no steatosis, no necrosis, no cholestasis, no iron accumulation and no amyloidosis. Numerous eggs of Schistosoma mekongi were observed in five cases, mostly in fibrous areas and more rarely in the parenchyma. Eggs were round or oval, measuring 60 x 40 microns with an acid-fast thin hyaline wall. Some eggs were surrounded by epithelioid and giant cell reaction. In conclusion, our findings illustrated a surprisingly high degree of fibrosis among young adults which contrasts with other schistosomiasis.

Late postoperative follow-up of patients undergoing subtotal splenectomy

PURPOSE

Over the past 21 years, we have performed more than 200 subtotal splenectomies, in which the upper splenic pole vascularized only by the gastrosplenic pole vascularized only by the gastrosplenic vessels is preserved, to treat different pathologic conditions. A meticulous follow-up of the postoperative results of this procedure is of fundamental importance.

METHODS

All patients undergoing subtotal splenectomy were invited to be reviewed. A total of 86 patients who had undergone surgery 1 to 20 years ago were gathered; the surgical procedure was performed for one of the following conditions: portal hypertension due to schistosomiasis (n = 43), trauma (n = 31), Gaucher's disease (n = 4), myeloid hepatosplenomegaly due to myelofibrosis (n = 3), splenomegalic retarded growth and sexual development (n = 2), severe pain due to splenic ischemia (n = 2) and pancreatic cystadenoma (n = 1). Patients underwent a hematologic exam, an immunologic assessment, abdominal ultrasonography, computed tomography, scintigraphy and endoscopy.

RESULTS

Increased white blood cell count and platelets were the only hematological abnormalities. No immunologic deficit was found. Esophageal varices were still present in patients who underwent surgery because of portal hypertension although without rebleeding. The ultrasound, tomography and scintigraphy exams confirmed the presence of functional splenic remnants without significant size alteration.

CONCLUSIONS

Subtotal splenectomy seems to be a safe procedure that can be useful in treating conditions involving the spleen. The functions of the splenic remnants are preserved during long periods of time.

Hypertensive portal colopathy in schistosomiasis mansoni: proposal for a classification

Portal hypertension is a frequent complication of chronic liver disease, detected not only in schistosomiasis, but also in cirrhosis of any etiology. Vascular alterations in the colonic mucosa are a potential source for acute or chronic bleeding and have been observed in patients with portal hypertension. The purpose of this prospective study was to describe and propose a classification for the vascular alterations of portal hypertension in the colonic mucosa among patients with hepatosplenic schistosomiasis mansoni. One or more alterations of portal colopathy were observed in all patients and they were classified according to their intensity, obeying the classification proposed by the authors. Portal colopathy is an important finding in hepatosplenic schistosomiasis and might be the cause of lower gastrointestinal bleeding in patients with severe portal hypertension.

The influence of periportal (pipestem) fibrosis on long term results of surgical treatment for schistosomotic portal hypertension

AIM

To evaluate the degree of influence that periportal fibrosis has on clinical development and the long term results of surgical treatment on patients with hepatic-splenic schistosomiasis with previous gastrointestinal hemorrhages.

METHODS

During the period of 1992-1998, 111 patients underwent surgical treatment for the treatment of hepatic-splenic schistosomiasis with previous gastrointestinal hemorrhages. The degree of fibrosis was classified as: degree I - the portal spaces show a rich increase of young connective cells, a slight collagen production and a varying presence of inflammatory infiltrate. The periportal blade unchangeable (29/111); degree II - there is an expansion of the connective tissue with the emission of radial collagen septa, producing a star shaped aspect (38/111); degree III - the connective septa form bridges with other portal spaces or with the vein, with evident angiomatoid neo-formation (44/111).

CONCLUSION

The patients with periportal fibrosis degree I present recurrent hemorrhages statistically less than patients with periportal fibrosis degrees II and III, and that the intensity of the periportal fibrosis is not the only pathophysiological factor of the esophageal varices, gastric varices, prevalence of post-operative portal vein thrombosis and hematological and biochemical alterations of the patients with pure mansoni schistosomiasis.

[Portal hypertension and schistosomiasis: "an originally killing entity"]

In some regions of Africa, Middle-east and Asia, portal hypertension is caused most frequently by bilharziasis far more than by post-hepatic or alcoholic cirrhosis. All schistosomiasis induce hepatic affection, consequence of the eggs embolization in the vessels endings of the portal system, but only Schistosoma mansoni and Asian bilharziasis mainly the Schistosoma japonicum are the cause of severe sequelar fibrosis responsible for a particular portal hypertension. This portal hypertension is original anatomopathologically and physiopathologically. The perivascular concentric fibrosis localised in the portal space is an anatomopathological sequela of bilharzious granulomas outlining embolized eggs. This "stem pipe" aspect constitutes a presinusoidal block inducing a severe portal hypertension without hepatic lobule affection. The recent medical advances regarding this pathology lie in the understanding of the responsible immune mechanisms, the diagnosis and follow-up thanks to ecographic codification of lesions, the complications treatment through varix endoscopic ligature or portal vein derivation. Treatment by praziquantel remains justified together with health education, improving living standard and hopes placed in the future vaccination campaigns associated with medical treatment in endemic areas.

[Decompensated post-schistosomiasis portal hypertension in Richard-Toll, Senegal: first case treated by splenorenal anastomosis in Dakar]

Since the Diama dam on the Senegal river became operative in 1986, an exceptional outbreak of intestinal schistosomiasis occurred in northern Senegal. This is the first case report from this region of a splenorenal derivation performed in Dakar to cure decompensated portal hypertension due to Schistosoma mansoni.

CASE REPORT

In June 1998, a 16-year old boy, native from Richard-Toll in the Senegal River Basin, was admitted to the paediatric department of Hôpital Principal, Dakar, Senegal, with a 3 years of recurrent hematemesis. Blood transfusions were required despite propranolol and multiple oesophageal varices sclerotherapies. On admission he weighed 33 kg and was noted to have pallor and moderate hepatosplenomegaly. Lab work included normal liver function tests, a Hgb of 58 mg/L, negative HBs antigen, and high titers of schistosomiasis antibodies (> 1/2000 by the hemagglutination method). Ultrasound revealed an homogeneously enlarged liver, periportal fibrosis and spleen with a grade 2 portal hypertension (WHO score). Endoscopy showed stage 3 oesophageal varices with red spots but no active haemorrhage. After transfusions, a Warren distal splenorenal anastomosis was performed. During the operation, a liver biopsy was obtained, showing periportal fibrosis and schistosomiasis granulomas. The patient was discharged without complication. After 4 years he remains free of any recurrence of his upper gastrointestinal haemorrhage and haemoglobin rate is normal.

COMMENTS

Before the inauguration of the dam in 1986, S. mansoni infection was never reported from the Senegal River Basin. But as early as 1988, the first cases of intestinal schistosomiasis began to show up. A few years later, this focus had dramatically extended and in 1991 the first cases of hepatic fibrosis were detected in ultrasonography surveys. The present case involves the first patient from northern Senegal who required surgery for haemorrhagic complications of schistosomiasis induced by liver disease. Considering the high prevalence in this area, and the difficulties of medical management, the need for porto-systemic derivations is likely to rise. These operations are difficult and require specially trained surgeons. They have been largely unavailable in Senegal until now. This case report, involving a child only 10 years after the beginning of the epidemic, underlines the acute need for improving both prevention and medical treatment in order to avoid progression to clinical stages of hepatic schistosomiasis where surgery is unavoidable. In addition, the training of local surgical teams able to deal with these complications is urgently needed in Senegal.

Surgical indication in Schistosomiasis mansoni portal hypertension: follow-up from 1985 to 2001

The study had the objective to evaluate the benefits of surgical indication for portal hypertension in schistosomiasis patients followed from 1985 to 2001. Schistosoma mansoni eggs were confirmed by at least six stool examinations or rectal biopsy. Clinical examination, abdominal ultrasonography, and digestive endoscopy confirmed the diagnosis of esophageal varices. A hundred and two patients, 61.3% male (14-53 years old) were studied. Digestive hemorrhage, hypersplenism, left hypochondrial pain, abdominal discomfort, and hypogonadism were, in a decreasing order, the major signs and symptoms determining surgical indication. Among the surgical techniques employed, either splenectomy associated to splenorenal anastomosis or azigoportal desvascularization, esophageal gastric descompression and esophageal sclerosis were used. Follow-up of patients revealed that, independent on the technique utilized, a 9.9% of death occurred, caused mainly by digestive hemorrhage due to the persistence of post-treatment varices. The authors emphasize the benefits of elective surgical indication allowing a normal active life.

Measuring morbidity in schistosomiasis mansoni: relationship between image pattern, portal vein diameter and portal branch thickness in large-scale surveys using new WHO coding guidelines for ultrasound in schistosomiasis

OBJECTIVE

World Health Organization consensus meetings on 'Ultrasound in Schistosomiasis' in 1996 and 1997 anticipated further challenges in the global implementation of a standardized protocol for morbidity assessment in schistosomiasis mansoni. We evaluated the performance of the qualitative and quantitative components of the new Niamey criteria.

METHOD

Use of the Niamey protocol among 3954 subjects in two linked, cross-sectional ultrasound surveys of Schistosoma mansoni-endemic populations in Egypt and Kenya.

RESULTS

There were significant differences between Egyptian and Kenyan sites in prevalence and age distribution of S. mansoni-related hepatic fibrosis (36%vs. 3%, P < 0.001). Protocol image pattern scoring could be performed quickly and was stable to interobserver variation. However, there were unintended but systematic differences between study sites in the measurement of portal vein diameter (PVD) and wall thickness. By Niamey criteria, a high prevalence of portal dilation was scored for normal Egyptian subjects, which reduced the predictive value of image pattern for portal hypertension. Using alternative height-indexing of PVD, image pattern plus PVD findings predicted 15% of Egyptians and 2.5% of Kenyans were at risk for variceal bleeding, whereas locally derived PVD norms estimated 25% of Egyptians and 12% of Kenyans to be at possible risk.

CONCLUSION

Niamey scoring criteria performed acceptably as a relative grading system for disease in schistosomiasis mansoni, but failed to account fully for site-to-site variation in test performance and morbidity prevalence. Consequently, standardized image pattern scoring appears to provide the most useful tool for detection and comparison of S. mansoni-associated morbidity in large-scale surveys.

Portopulmonary hypertension syndrome in schistosomiasis mansoni

Portopulmonary hypertension syndrome (PPHS) is a complication of portal hypertension where the substrate is micro-vessel lesions which are indicative of plexogenic arteriopathy. PPHS has not been linked to pulmonary schistosomiasis. We report, to the best of our knowledge for the first time, a case of PPHS associated with schistosomiasis mansoni.

Thrombopoietin serum levels do not correlate with thrombocytopenia in hepatic schistosomiasis

BACKGROUND

In severe forms of cirrhosis reduced liver synthesis of thrombopoietin (Tpo) can contribute to thrombocytopenia. In the hepatosplenic form of schistosomiasis, portal hypertension is the most evident clinical complication, although a deficiency of protein synthesis may be detected early. Our aim was to determine, for the first time in schistosomiasis, Tpo serum concentrations in patients with chronic forms of the disease.

METHOD

Twenty-four patients with the pure form of schistosomiasis were studied; 13 had the hepatosplenic form (HE, with portal hypertension) and 11 had the hepatointestinal form (HI, without portal hypertension). Patients were HBsAg, anti-HBc and anti-HCV negative, and reported alcohol ingestion below 160 g/week.

RESULTS

The Tpo serum concentration, determined in 10 healthy volunteers, varied from undetectable (< 15 pg/mL) to 489 pg/mL (median 208 pg/mL). The HE and HI groups differed (p = 0.004) in regard to the prothrombin index, thrombocytemia and gamma-glutamyltransferase but not in regard to Tpo (p = 0.622). No significant correlation was found between Tpo and the other parameters (p > 0.05).

CONCLUSIONS

The results suggest that Tpo serum concentration does not mirror and/or has no significant participation in the mechanisms responsible for the thrombocytopenia observed in schistosomiasis patients with splenomegaly and portal hypertension.

[Anemia, eosinophilia and generalized weakness in a 20-year old African]

CASE HISTORY AND DIAGNOSIS

A 20-year-old African man was admitted to hospital with anemia, eosinophilia, raised liver enzymes and hepatosplenomegaly. Previously, on arrival in Germany, he had undergone a routine medical check-up where simple microscopy of a feces sample as well as serology for lues, AIDS and hepatitis B had all been negative. In our hospital a stool specimen was examined for ova and parasites and revealed ova of Schistosoma mansoni and confirmed the diagnosis of bilharziosis. For the detection of helmintic ova repeated stool examinations with use of concentration techniques are required. Staging by endoscopies, ultrasonography revealed colon pseudopolyposis and periportal fibrosis complicated by portal hypertension and esophageal varices.

TREATMENT AND COURSE

Chemotherapy with Praziquantel was effective in eliminating the parasites but in advanced stages chronic fibrotic changes are usually irreversible. Further monitoring will therefore be necessary in our patient.

CONCLUSION

Due to increasing migration and international travel, also doctors working in industrialized countries should be aware of tropical diseases.

Geographic differences in hepatosplenic complications of schistosomiasis mansoni and explanatory factors of morbidity

In a study in three neighbouring villages of southern Madagascar, where Schistosoma mansoni is hyperendemic, ultrasound examination using the Niamey protocol showed marked differences in the burden of disease from one village to another. Hepatosplenic schistosomiasis was more frequent in the village with the highest geometric mean egg counts and the earliest onset of infections, demonstrating that the morbidity induced by S. mansoni may vary greatly within a given area. True representativeness of study populations, a keystone of epidemiological studies, is mandatory to obtain a clear picture of a wide area. Ultrasound examinations in a small number of villages, or even a single one, may be a questionable approach. Using logistic regression analysis, the explanatory variables found to be significantly associated with a risk of severe hepatosplenic disease in our study were sex, age, village of residence and S. mansoni egg counts. On the other hand, a concurrent infection with an intestinal helminth seems to reduce the risk of severe hepatosplenic disease. Further studies should assess the role and possible impact of intestinal helminths on S. mansoni associated-morbidity.

Surgical treatment of schistosomal portal hypertension

Schistosomiasis mansoni is a widespread parasitic disease in the Brazilian territory that affects over 8 million individuals. Hepatosplenic schistosomiasis is a serious clinical presentation of this disease, associated with splenomegaly, liver fibrosis, and portal hypertension, and is responsible for approximately 7% of schistosomotic patients. The surgical treatment of portal hypertension in schistosomotic patients has distinct features when compared with cirrhotic patients, mostly because hepatic function is preserved in schistosomotic liver disease. Therefore, when attempting to reduce the portal pressure, the surgeon must be aware that the surgery might interfere with hepatic perfusion, and consequently with hepatic function. The aim of this study was to report the results achieved with splenectomy, division of the left gastric vein, devascularization of great gastric curvature, and postoperative endoscopic variceal sclerosis, as a surgical option to esophageal varices in hepatosplenic schistosomiasis. A total of 111 patients were studied, and the following is a list of inclusion criteria: age >16 years, history of gastrointestinal (GI) bleeding, presence of esophageal varices on preoperative endoscopy, hematocrit >22% and prothrombin enzymatic activity >50%, negative viral hepatitis on serologic tests (anti-HBV and anti-HCV), and definition, after liver biopsy, of exclusive schistosomotic liver disease. The following list includes exclusion criteria used: presence of liver disease other than schistosomotic, history of alcohol abuse, and preoperative thrombosis of the portal vein. The rebleeding rate was 14.4% during a mean 30-month follow-up period; portal vein thrombosis was 13.2%, and there was a global mortality of 5.4%. Gastric varices were present in 46.9% of the patients; for those patients, a gastrotomy and running suture of the varices achieved an eradication rate of the varices of 75.6%. The degree of periportal fibrosis was also analyzed. Periportal fibrosis staging revealed that patients with class II or III liver fibrosis had a significant increased risk of recurrent GI bleeding when compared with patients with class I liver fibrosis. Despite the elevation on alanine aminotransferase (ALT) and aspartate aminotransferase (AST), most other liver function tests showed no alteration or were corrected after surgery. We conclude that splenectomy, division of the left gastric vein, devascularization of great gastric curvature, and postoperative endoscopic variceal sclerosis showed good results globally and should be considered as therapeutic options in the treatment of hepatosplenic schistosomiasis.

[Predictive ultrasonographic criteria for portal hypertension due to Schistosoma mansoni in a recently established endemiz zone]

The first cases of Schistosoma mansoni infection were reported in the Senegal River Basin ten years ago. Today endemicity is so high that prevalence rates exceed 90 p. 100 in some areas. Schistosomiasis sometimes goes undiagnosed until the occurrence of portal hypertension with rupture of esophageal varices. Endoscopy is the gold standard for detection of esophageal varices but it is impractical in remote areas. Ultrasonography has been proposed as a non-invasive alternative. The purpose of this study is to describe the results of simultaneous endoscopic and ultrasonographic assessment in 101 subjects from the Richard-Toll area of the Senegal River Basin. Findings showed that severe forms of schistosomiasis complicated by portal hypertension were already present in the region less 10 years after description of the first case. This study also proposes a diagnostic score for portal hypertension based on ultrasonographic findings. The features included in this score are thickening of portal vessel walls, portal vessel diameter, and collapsed appearance of the splenic vein during inspiration. In our hands this score allowed reliable prediction of the development of esophageal varices. Ultrasonography is a good tool for identifying severe forms of schistosomiasis. It should be useful for routine screening in recently established endemic zones.

Systemic hemodynamic changes in mansonic schistosomiasis with portal hypertension treated by azygoportal disconnection and splenectomy

OBJECTIVE

The aim of this study was to assess systemic hemodynamic changes in patients with Manson's schistosomiasis and portal hypertension during azygoportal disconnection and splenectomy.

METHODS

Sixteen patients with portal hypertension secondary to hepatosplenic schistosomiasis with indication for surgery were studied prospectively. All underwent invasive hemodynamic monitoring with pulmonary artery catheter. The first systemic hemodynamic assessment was performed preoperatively. In the intraoperative period new hemodynamic data were collected as follows: a) after laparotomy; b) 15-30 min after splenic artery ligature; c) 15-30 min after splenectomy; and d) after ligation of the collateral circulation.

RESULTS

The results indicated preoperatively that the patients presented with an increased cardiac index (4.40 +/- 0.94 L/min/m2) together with a reduction in the systemic vascular resistance index (1692.25 +/- 434.91 dyne.s/cm5.m2). The stroke index (53.74 +/- 10.40 ml/beat/m2) and both left (5.71 +/- 1.50 kg.m/m2) and right heart work indexes (1.12 +/- 0.74 kg.m/m2) were also elevated. The mean pulmonary artery pressure was increased (17.81 +/- 9.00 mm Hg) and the pulmonary vascular resistance index decreased (164.31 +/- 138.69 dyne.s/cm5.m2). From the moment that the splenic artery was ligated until the end of the procedure, the cardiac index (3.45 +/- 0.90 L/min/m2) was reduced and the systemic vascular resistance index (2059.50 +/- 590.05 dyne.s/cm5.m5) increased. The systolic index (44.25 +/- 11.01 ml/beat/m2) and the left ventricle work index (4.33 +/- 1.29 kg.m/m2) also reduced. The mean pulmonary artery pressure (19.18 +/- 9.21 mm Hg) and the right ventricle work index (0.94 +/- 0.62 mm Hg) remained elevated after the surgical procedure.

CONCLUSIONS

The data allowed us to conclude that hepatosplenic schistosomiasis induces a hyperdynamic circulatory state that was corrected after splenectomy and azygoportal disconnection, remaining a mild pulmonary hypertension. Therefore, these changes are correlated with the portosystemic collateral circulation, especially as a consequence of splanchnic hyperflow.

Schistosome-induced portacaval haemodynamic changes in Rattus rattus are associated with translocation of adult worms to the lungs

The presence of naturally portacaval shunts has been investigated in the vasculature of normal and Schistosoma mansoni-infected Rattus rattus. Using the technique of injecting Polystyrene microspheres in the superior mesenteric vein, we demonstrated that the presence of adult schistosomes in the lungs of R. rattus was not due to an innate anomaly of the rat vasculature but resulted from the formation of portacaval shunts during infection. In rats harbouring a bisexual infection, microspheres were only detected in the lungs from week 7. The development and increasing size of the shunts were maximal between weeks 7 and 10 and coincident with the translocation of adult worms from the portal tract to the lungs. At weeks 20-25, only 1-2% of the microspheres were recovered from the lungs, suggesting that the portacaval anastomoses have regressed due to reduction in portal hypertension after worm translocation. R. rattus with a male-only schistosome infection harboured adult worms in the lungs, indicating that the development of shunts does not solely depend upon egg deposition in the liver to generate hypertension. The relationships between the presence of the schistosomes in the lungs, the portacaval shunting and the resistance to reinfection is discussed.

Late postoperative follow-up of patients submitted to subtotal splenectomy

Subtotal splenectomy preserving the upper splenic pole vascularized only by the splenogastric vessels has been performed by us in 91 patients since 1984. This procedure was combined with central splenorenal shunt or portal variceal disconnection to treating schistosomatic portal hypertension (n = 67); it was combined with distal pancreatectomy to treat pancreatic cystadenoma (n = 1), and it was carried out for severe splenic trauma (n = 14), and to control severe Gaucher's disease (n = 4) and myeloid metaplasia due to myelofibrosis (n = 5). All patients are alive. In the present paper, we present the late postoperative follow up of 32 patients operated in a period that ranges from 1 to 12 years. All patients are satisfied with the operation. Increased counts of white blood cell (n = 10) and platelets (n = 7) were the only hematological alterations. Esophageal varices were present in 23 of 27 patients operated due to portal hypertension, but all of them were shorter than in the preoperative period. The ultrasound confirmed the presence of the splenic remnant (30 of 32) without significant size changes. Splenic scintigraphies were positive in 30 of 32 patients. Subtotal splenectomy seems to be a safe procedure that can be useful in portal hypertension, some metabolic and hematological diseases, and benign growth of the distal pancreas.

Cardiopulmonary manifestations of schistosomiasis

Three major schistosome species infect hundreds of millions of people worldwide. The majority of these infections are asymptomatic, but significant morbidity and mortality can occur as a consequence of ongoing egg deposition in host tissues. Acutely, transient chest radiographic abnormalities and nonspecific influenza-like symptoms can occur, including cough. The most common chronic pathological sequelae of schistosomiasis are those of portal hypertension with Schistosoma mansoni or S. japonicum, and genitourinary tract obstruction with S. haematobium. In less than 5% of infections, schistosomal egg obstruction of the lung vasculature results in pulmonary hypertension and cor pulmonale. Limited data suggests that cardiopulmonary schistosomiasis is seen most often in S. mansoni infections. Hepatic fibrosis and portal hypertension appear to be a prerequisite to the development of schistosomal cor pulmonale caused by this species. The premortem diagnosis of cardiopulmonary schistosomiasis depends on the detection of viable schistosomal ova in stool or urine along with evidence of characteristic hepatic fibrosis and pulmonary hypertension. Although treatment with praziquantel can effectively eradicate all schistosomal infections with minimal toxicity, cardiopulmonary manifestations are not likely to be reversible given the chronic fibrotic tissue changes that are present.

Imaging findings in giant pseudotumoral paraesophageal varices

We report a case of variceal changes of the azygos vein, hemiazygos vein, and paraesophageal collaterals presenting as bilateral posterior mediastinal masses in a patient with long-standing portal hypertension due to hepatosplenic schistosomiasis. The case is unusual because the varices were considerably larger than those usually encountered in portal hypertension. Dynamic CT allowed the diagnosis in demonstrating the vascular nature of these masses, which enhanced to the same degree as the other vessels. Noninvasive techniques, such as color Doppler sonography and MRI, may also be useful due to their multiplanar capabilities.

Risk factors in surgery of gastroduodenal ulcer disease in patients with schistosomal portal hypertension

The present study was conducted to determine the risk factors associated with surgical treatment of peptic ulcer disease (PUD) in patients with schistosomal hepatic fibrosis (SHF). The medical records of 32 patients treated at the Department of Surgery, Alexandria Faculty of Medicine between 1984 and 1994 were reviewed and data were analyzed. Twenty-five patients were male and seven were female, with a mean age of 43.3 +/- 24. Fifteen patients belonged to Child A and 13 to Child B. Twenty-one patients were variceal non-bleeders and 11 were bleeders. The ulcer was pyloric or duodenal in 30 patients and gastric in only two. Twenty-four patients were operated upon electively mostly for pyloric obstruction (n = 15) and eight patients emergently; five for perforation and three for bleeding. Hepatic insufficiency, renal function impairment and gastrointestinal bleeding were the most detrimental postoperative complications that occurred, either alone or in combination, in 13 patients (40.6%). Eight patients died (25%) of liver failure (n = 5), gastrointestinal bleeding (n = 2) and multiple systems organ failure (n = 1). Urgency of the operation and Child B were of significance for predicting mortality in contrast to age, sex, liver size, bleeding varices and ulcer location. Based on these data, it may be concluded that 1) operations for PUD in patients with schistosomal portal hypertension are expected to have high postoperative morbidity and mortality; 2) mortality rate significantly increases by emergency operations, presence of postoperative complications and in modified Child B patients; 3) Liver function must be optimized preoperatively; and 4) the most simple and expeditious procedure must be performed to minimize postoperative complications and hepatic decompensation.

Tropical gastrointestinal disease: hepatosplenic schistosomiasis--pathological, clinical and treatment review

S. mansoni and S. japonicum complex schistosomes cause hepatosplenic and hepatointestinal schistosomiasis. The prevalence and incidence of this disease is increasing in all the endemic areas. Hepatosplenic schistosomiasis is seen in a small subset of clinically infected patients and represents a good model of intrahepatic portal hypertension characterised by a presinusoidal portal block and a well preserved liver parenchyma. Symmers' fibrosis is seen in a significant proportion of patients with high worm load. While the pathogenesis of Symmers' pipe stem fibrosis has not been well established, experimental and clinical data point to egg induced granulomata. The main consequences are presinusoidal portal hypertension, oesophageal varices and hepatosplenomegaly. The most striking symptoms are haematemesis or melena secondary to variceal and gastrointestinal bleeding. Cofactors associated with the pathogenesis include aflatoxins, malnutrition, alcoholism, hepatitis B and C virus. While stool examination is the best technique for diagnosis, a number of immunological tests though sensitive are not specific. Ultrasonography is sensitive for detection of Symmer's fibrosis. Praziquantel and oxaminiquine are drugs found to be effective in the treatment of hepatosplenic schistosomiasis. Recently beta-blockers have been found to be effective in the treatment of gastrointestinal rebleeding. Endoscopic sclerotherapy has been found to be effective for treatment of bleeding oesophageal varices. The treatment of choice for portal hypertension is oesophagogastric devascularization with splenectomy (EGDS).

Sonographic features of portal hypertension in schistosomiasis mansoni

The diagnostic value of real-time sonography in the study of portal hypertension was assessed in 66 patients with hepatosplenic schistosomiasis mansoni, all with Symmers's fibrosis and esophageal varices. Seventy-one individuals without schistosomiasis were selected as controls. The inner diameters of the portal vessels were measured by sonography in all patients and controls: splenoportography was also performed in the schistosomal group. Intra-splenic pressure was over 30 cm of water in 44 of 60 patients with schistosomiasis. The upper limit of normality for portal vessel diameters was set through receiver operating characteristic curve at 12 mm for portal vein, 9 mm for splenic vein at splenic hilus, and 9 mm for superior mesenteric vein. The best discriminative vein for the diagnosis of portal hypertension was the splenic vein followed by the portal vein. A direct correlation was observed between the diameter of the splenic vein, measured by sonography, and the intra-splenic pressure. Except for the paraumbilical and mesenteric veins, more frequently identified by sonography, there was no statistical difference in the frequency of visualization of splanchnic vessels by sonography or splenoportography.

[Critical evaluation of schistosomiasis portal hypertension surgery]

There are over 100,000 patients affected by schistosomotic portal hypertension, that may suffer rupture of the esophageal varices. Besides the portal hypertension, local factors must be emphasized as responsible for the three distal centimeters of the esophagus, called "zona vulnerável" (vulnerable zone). The better liver functional reserve of these schistosomotic patients as compared to the cirrhotic, present two favorable conditions: (1) better possibility of conservative treatment during acute hemorrhage; (2) elective surgical treatment may be undergo without a mandatory step of large portal decompression. The Author only indicate surgical treatment in patients with hemorrhage antecedent and his preference consist in splenectomy plus obliterative suture of the varices at the "vulnerable zone" and when possible, ligature of left gastric vein also; 358 patients were undergone surgery with operative mortality 3.07%; 347 were followed during 1 to 25 years; late mortality 8.38%; recurrence hemorrhage 11.58%; none porto-systemic encephalopathy was observed.

Portal hypertension in schistosomiasis: pathophysiology and treatment

In heavily infected young patients, there is a "non-congestive" phase of the disease with splenomegaly which can improve after chemotherapy. A strong correlation between hepatosplenic form and worm burden in young patients has been repeatedly shown. The pattern of vascular intrahepatic lesions, seems to depend on two mechanisms: (a) egg embolization, with a partial blocking of the portal vasculature; (b) the appearance of small portal collaterals along the intrahepatic portal system. The role played by hepatitis B virus (HBV) and C virus infections in the pathogenesis of liver lesions is variably considered. Selective arteriography shows a reduced diameter of hepatic artery with thin and arched branches outlining vascular gaps. A rich arterial network, as described in autopsy cases, is usually not seen in vivo, except after splenectomy or shunt surgery. An augmented hepatic arterial flow was demonstrated in infected animals. These facts suggest that the poor intrahepatic arterial vascularization demonstrated by selective arteriography in humans is due to a "functional deviation" of arterial blood to the splenic territory. The best results obtained in treatment of portal hypertension were: esophagogastric devascularization and splenectomy (EGDS), although risk of rebleeding persists; classical (proximal) splenorenal shunt (SRS) should be abandoned; distal splenorenal shunt may complicate with hepatic encephalopathy, although later and in a lower percentage than in SRS. Propranolol is currently under investigation. In our Department, schistosomatic patients with esophageal varices bleeding are treated by EGDS and, if rebleeding occurs, by sclerosis of the varices.

Pathogenesis of varices in schistosomal portal hypertension

Patients with schistosomiasis and portal hypertension have significantly lower levels of hydroxyproline in their saphenous veins and anterior rectus sheaths than do individuals without schistosomal hepatic fibrosis. The stomach of patients with schistosomal portal hypertension demonstrates an increased number of lymphatics by lymphangiography. The disrupted lymph node architecture in these patients could be partially responsible for dilation, tortuosity, and retrograde lymph flow in the gastric lymphatics. These histological and lymphangiographic findings could be attributed to the effect of venous and patients with decompensated schistosomal portal hypertension revealed edema of the entire esophageal wall with lymphatic dilation and tortuosity. Based upon these data, we suggest that the varices that develop in patients with schistosomal portal hypertension occur as a consequence of an increased portal venous pressure together with acquired lymphangiectasia as well as an intrinsic weakness of the walls of the portosystemic venous channels.

Sonographic changes following splenectomy for portal hypertension in Schistosoma mansoni

Eleven patients with portal hypertension due to infection with Schistosoma mansoni underwent splenectomy and devascularization operations. The patients were examined with ultrasound once preoperatively and twice postoperatively over a period of about 6 months. Following surgery there was significant and sequential reduction in the diameter of the portal vein at the hilum and the splenic vein at the pancreas. The liver lengths and index of liver size did not change significantly. No changes in the degree of periportal fibrosis could be detected.

Hepatosplenic schistosomiasis. Pathophysiology and treatment

HSS represents a special model of intrahepatic portal hypertension characterized by a presinusoidal portal block and a well-preserved liver parenchyma. Symmers' fibrosis appears in a small but significant proportion of patients with a high worm load. Its pathogenesis is not well established, although experimental and clinical studies point to egg granulomata as the main pathogenetic factor. The eggs carried continuously through the portal circulation produce inflammation and gross amputation of the intrahepatic veins, portal and periportal granulomas, and, eventually, a coarse perilobular fibrosis ("pipe-stem"). Portal hypertension, esophageal varices, and hepatosplenomegaly are the main consequences of these morphologic changes. Gastrointestinal bleeding is the most frequent cause of death. Unlike in cirrhosis, advanced liver failure is not seen except when HSS is associated with liver lesions from other causes such as virus and alcoholism. Helminthiasis treatment is based on chemotherapy with praziquantel or oxamniquine. Bleeding esophageal varices are managed by sclerotherapy or surgical procedures. Splenectomy with gastroesophageal devascularization seems to be the best choice.

Resistance to reinfection in experimental murine schistosomiasis: role of porto-hepatic hemodynamics

Experiments were conducted to evaluate critically, and independently of the immune system, the possible role of hemodynamic mechanisms in resistance to schistosomal reinfection. The effects of a challenge schistosomal infection were compared in groups of mice which were either previously infected with schistosomiasis, vaccinated with irradiated cercariae, or underwent partial portal vein ligation for the induction of portal hypertension and porto-systemic shunting. Following infection with 60 cercariae, the appearance of portal hypertension preceded by approximately 2 weeks the development of porto-systemic shunting, which reached maximal values 11 weeks postinfection. Such a primary infection conferred on C3H mice an estimated 90% protection to a 2nd infection, measured by the reduction of worm burden. Worm burdens were also reduced in vaccinated and ligated animals as compared to normal controls. The protection amounted to 30% and 56%, respectively, in the C3H strain and 63% and 75-85%, respectively, in the C57Bl/6 strain. Reduction in worm burden in the ligated animals is believed to be due to the extrahepatic porto-systemic vascular shunts. Hemodynamic as well as immunological factors may account for the resistance to reinfection observed in chronic murine schistosomiasis.

Renal function and morphology in Sudanese patients with advanced hepatosplenic schistosomiasis and portal hypertension

The association between glomerular disease and hepatosplenic schistosomiasis is well documented in reports from South America. During the present hospital investigation in Sudan, 58 patients admitted for intercurrent complications of advanced hepatosplenic schistosomiasis were studied. The patients, median age 35 years, had no concurrent Schistosoma haematobium infection. Diagnostic criteria included an enlarged spleen (n = 58), at least 1 episode of hematemesis (n = 55) and/or melena (n = 36), endoscopical demonstration of gastroesophageal varices (29/29 studied), ultrasonographical imaging of hepatic periportal fibrosis (18/18 studied), and intraoperative liver biopsy with characteristic histological findings (11/16 biopsied). Serum creatinine, urea, electrolytes, cholesterol, total protein, and electrophoresis were within normal limits. Median urinary protein/creatinine ratio was 0.06 and thereby not significantly different from European reference values. Only 1 patient had proteinuria of 1.7 g/l. Minimal hematuria was found in 5 patients. Ten kidney biopsies were taken intraoperatively during a portal decompression procedure (Hassab operation). Light, immunofluorescence, and electron microscopy produced no evidence of glomerulonephritis. These findings indicate that S. mansoni induced nephrotic syndrome may be less frequent in Sudan than in South America. Renal involvement due to S. mansoni infection may therefore encompass geographical variances.

Schistosoma mansoni: effects of anesthetics and antimonial drugs on worm shift in the mouse

Mice experimentally infected with Schistosoma mansoni were injected with sodium thiopental or sodium antimonyl gluconate (Triostib R), or submitted to halothane inhalation, with or without a previous injection of thiopental. Data obtained showed that halothane and thiopental induce worm shift to the liver (99 and 76%, respectively). Sodium gluconate and antimonium (Triostib R) shifted 52% of worms towards the liver. These results seem to indicate that the use of antimonium would be unnecessary, when surgical removal of schistosomules is carried out through the extracorporeal filtration technique, in patients with portal hypertension.

Portal hypertension and hypersplenism in pregnancy secondary to chronic schistosomiasis. A case report

In this country, Schistosoma mansoni infections are seen rarely since the distribution of schistosomes in humans is governed by the range of their molluscan hosts. The snail hosts of S. mansoni reside in fresh waters of tropical zones. A native of Brazil was seen in her second trimester of pregnancy with marked splenomegaly and hypersplenism. Thirteen years before she had been treated for schistosomiasis, and she had been well until her pregnancy. Studies were done to rule out other causes of splenomegaly and hypersplenism. Esophageal endoscopy confirmed the presence of esophageal varices. The main risk to these patients is severe, sometimes fatal gastrointestinal bleeding. In our patient this risk was compounded by marked thrombocytopenia. Splenectomy was performed, and a liver biopsy confirmed the presence of S. mansoni eggs.