Imaging techniques and histology in the evaluation of liver fibrosis in hepatosplenic schistosomiasis mansoni in Brazil: a comparative study

Functional autoantibodies against G protein-coupled receptors in hepatic and pulmonary hypertensions in human schistosomiasis

Introduction

Schistosomiasis (SM) is a parasitic disease caused by Schistosoma mansoni. SM causes chronic inflammation induced by parasitic eggs, with collagen/fibrosis deposition in the granuloma process in the liver, spleen, central nervous system, kidneys, and lungs. Pulmonary arterial hypertension (PAH) is a clinical manifestation characterized by high pressure in the pulmonary circulation and right ventricular overload. This study investigated the production of functional autoantibodies (fAABs) against the second loop of the G-protein-coupled receptor (GPCR) in the presence of hepatic and PAH forms of human SM.

Methods

Uninfected and infected individuals presenting acute and chronic manifestations (e.g., hepatointestinal, hepato-splenic without PAH, and hepato-splenic with PAH) of SM were clinically evaluated and their blood was collected to identify fAABs/GPCRs capable of recognizing endothelin 1, angiotensin II, and a-1 adrenergic receptor. Human serum was analyzed in rat cardiomyocytes cultured in the presence of the receptor antagonists urapidil, losartan, and BQ123.

Results

The fAABs/GPCRs from chronic hepatic and PAH SM individuals, but not from acute SM individuals, recognized the three receptors. In the presence of the antagonists, there was a reduction in beating rate changes in cultured cardiomyocytes. In addition, binding sites on the extracellular domain functionality of fAABs were identified, and IgG1 and/or IgG3 antibodies were found to be related to fAABs.

Conclusion

Our data suggest that fAABs against GPCR play an essential role in vascular activity in chronic SM (hepatic and PAH) and might be involved in the development of hypertensive forms of SM.

The role of point-of-care ultrasound in the assessment of schistosomiasis-induced liver fibrosis: A systematic scoping review

BACKGROUND

Abdominal ultrasound imaging is an important method for hepatic schistosomiasis diagnosis and staging. Several ultrasound staging systems have been proposed, each attempting to standardise schistosomal periportal fibrosis (PPF) diagnosis. This review aims to establish the role of ultrasound in the diagnosis and staging of schistosomal PPF, and to map the evolution of ultrasound staging systems over time, focusing on internal validation and external reproducibility.

METHODS

A systematic search was undertaken on 21st December 2022 considering the following databases: PubMed/MEDLINE (1946-present), Embase (1974-present), Global Health (1973-present), Global Index Medicus (1901-present), and Web of Science Core Collection-Science Citation Index Expanded (1900-present) and the Cochrane Central Register of Controlled Trials (1996-present). Case reports, systematic reviews and meta-analyses, and studies exclusively using transient or shear-wave elastography were excluded. Variables extracted included study design, study population, schistosomal PPF characteristics, and diagnostic methods. The PRISMA-ScR (2018) guidelines were followed to inform the structure of the scoping analysis.

RESULTS

The initial search yielded 573 unique articles, of which 168 were removed after screening titles and abstracts, 43 were not retrieved due to full texts not being available online or through inter-library loans, and 170 were excluded during full text review. There were 192 remaining studies eligible for extraction. Of the extracted studies, 61.8% (76/123) of studies that reported study year were conducted after the year 2000. Over half of all extracted studies (59.4%; 114/192) were conducted in Brazil (26.0%; 50/192), China (18.8%; 36/192) or Egypt (14.6%; 28/192). For the species of schistosome considered, 77.6% (149/192) of studies considered S. mansoni and 21.4% (41/192) of studies considered S. japonicum. The ultrasound staging systems used took on three forms: measurement-based, feature-based and image pattern-based. The Niamey protocol, a measurement and image pattern-based system, was the most used among the staging systems (32.8%; 63/192), despite being the most recently proposed in 1996. The second most used was the Cairo protocol (20.8%; 40/192). Of the studies using the Niamey protocol, 77.8% (49/63) only used the image patterns element. Where ultrasound technology was specified, studies after 2000 were more likely to use convex transducers (43.4%; 33/76) than studies conducted before 2000 (32.7%; 16/49). Reporting on ultrasound-based hepatic diagnoses and their association with clinical severity was poor. Just over half of studies (56.2%; 108/192) reported the personnel acquiring the ultrasound images. A small number (9.4%; 18/192) of studies detailed their methods of image quality assurance, and 13.0% (25/192) referenced, discussed or quantified the inter- or intra-observer variation of the staging system that was used.

CONCLUSIONS

The exclusive use of the image patterns in many studies despite lack of specific acquisition guidance, the increasing number of studies over time that conduct ultrasound staging of schistosomal PPF, and the advances in ultrasound technology used since 2000 all indicate a need to consider an update to the Niamey protocol. The protocol update should simplify and prioritise what is to be assessed, advise on who is to conduct the ultrasound examination, and procedures for improved standardisation and external reproducibility.

A case of chronic schistosomiasis in a Dongola stallion (Equus ferus caballus Linnaeus, 1758) from Nigeria

Schistosomiasis is a worldwide snail-borne parasitic infestation of man and animals with acute or chronic phases having devastating sequelae. The present case report focused on post-mortem examination of a cachexic Dongola stallion (Equus ferus caballus Linnaeus, 1758) in Abuja, Nigeria, that failed to respond to treatment. Typical dense collagenous granulomatous lesions with marked inflammatory responses and fibrosis occurred in the liver and several visceral organs of the horse along with other lesions indicative of systemic collapse. Special Ziehl-Neelsen and Periodic Acid-Schiff staining as well as microbial culture returned negative results to rule out acid-fast bacilli, fungal, and other bacterial involvement. In addition, the presence of a yellowish-brown eggshell within fibrosing granulomatous lesions led to the diagnosis of chronic schistosomiasis. Prolonged malnutrition under harsh and changing increment weather conditions with lack of medical care following the infection might have predisposed the horse to the recorded systemic collapse in the present case. The dearth of information on the ante-mortem evaluation of acute equine schistosomiasis cases notwithstanding, the observed lesions/cellular changes reinforced  associated multi-organ damages and systemic collapse in chronic cases. Our findings highlighted the pathological presentations and prognosis of chronic schistosomiasis and its triggers, especially in endemic areas, and in horses that often do not present obvious clinical manifestations.

Noninvasive diagnosis of periportal fibrosis in schistosomiasis mansoni: A comprehensive review

Schistosomiasis mansoni is a neglected disease and key public health problem, mainly due to its high prevalence, the scarcity of public policies, and the severity of some clinical forms. Periportal fibrosis (PPF) is the commonest complication of chronic schistosomiasis mansoni and its diagnosis requires different techniques. Even though wedge biopsy of the liver is considered the gold standard, it is not justified in non-surgical patients, and percutaneous liver biopsy may be informative but does not have sufficient sensitivity. Noninvasive PPF tests mostly include biological (serum biomarkers or combined scores) or physical assessments (imaging assessment of fibrosis pattern or tissue stiffness). Moreover, imaging techniques, such as ultrasound, computed tomography, magnetic resonance imaging, and elastography are applied not only to support the diagnosis of schistosomiasis, but also to assess and detect signs of portal hypertension and organ damage due to chronic schistosomiasis. A combination between a comprehensive history and physical examination with biomarkers for liver fibrosis and imaging methods seems to offer the best approach for evaluating these patients. In addition, understanding their strengths and limitations will allow a more accurate interpretation in the clinical context and can lead to greater accuracy in estimating the degree of fibrosis in patients with Schistosomiasis mansoni (S. mansoni) infection. This review will discuss the different noninvasive methods that are currently available for the evaluation of PPF in S. mansoni infection, and their application, advantages, and limitations in clinical practice.

Noninvasive predictors of esophageal varices in patients with hepatosplenic schistosomiasis mansoni

BACKGROUND

No previous study have evaluated transient elastography for predicting esophageal varices in hepatosplenic schistosomiasis.

AIM

To investigate noninvasive methods of predicting esophageal varices in patients with hepatosplenic schistosomiasis mansoni.

METHODS

Cross-sectional multicentric study included 51 patients with hepatosplenic schistosomiasis. Patients underwent ultrasonography-dopplerfluxometry, upper endoscopy, complete blood cell count and transient elastography (Fibroscan®) for liver and spleen stiffness measurement (LSM and SSM). Noninvasive scores previously established for cirrhotic population were studied: platelet count to spleen diameter ratio (PSR), LSM-spleen diameter to platelet ratio score (LSPS) and varices risk score (VRS). We proposed a version of LSPS and VRS by replacing LSM with SSM and named them SSPS and modified-VRS, respectively.

RESULTS

Esophageal varices were detected in 42 (82.4%) subjects. Individuals with varices presented higher SSM (73.5 vs 36.3 Kpa, p = 0.001), splenic vein diameter (10.8 vs 8.0 mm, p = 0.017), SSPS (18.7 vs 6.7, p = 0.003) and modified-VRS (4.0 vs 1.4, p = 0.013), besides lower PSR (332 vs 542, p = 0.038), than those without varices. SSPS was independently associated with varices presence (OR=1.19, 95%CI 1.03-1.37, p = 0.020) after multivariate analysis. In a model excluding noninvasive scores, SSM was independently associated with varices diagnosis (OR=1.09, 95%CI 1.03-1.16, p = 0.004). AUROC was 0.856 (95%CI 0.752-0.961, p = 0.001) for SSM and 0.816 (95%CI 0.699-0.932, p = 0.003) for SSPS (p = 0.551).

CONCLUSIONS

Spleen-related variables were predictors of esophageal varices: SSM, splenic vein diameter, SSPS, modified-VRS and PSR. Multivariate models indicated that SSM and SSPS are useful tools for predicting varices in non-cirrhotic portal hypertension by hepatosplenic schistosomiasis and may be used in clinical practice.

Evaluation of hepatic fibrosis by elastography in patients with schistosomiasis mansoni

BACKGROUND

Periportal fibrosis is associated with the main complications of schistosomiasis mansoni. The usefulness of hepatic transient elastography (TE) in its evaluation remains to be clarified.

METHODS

We conducted a cross-sectional study of schistosomal patients, where the measurements obtained by FibroScan TE were correlated with the degree of liver fibrosis according to the Niamey sonographic protocol, adopted as the gold standard, and its performance was calculated as the area under the receiver operating characteristics curve (AUROC).

RESULTS

A total of 117 of 141 adult schistosomiasis patients from endemic areas were selected between May and August 2015. Applying the Niamey protocol, the patients were regrouped into absent fibrosis (A; 34.2%), mild to moderate fibrosis (MM; 27.4%) and intense fibrosis (I; 38.5%). The median of the TE values in the patients of group A was 4.7 kPa, the group MM 9.3 kPa and the group I 10.3 kPa. There was a difference in the TE values between the group A and the groups MM and I (p < 0.05). The TE also presented strong and direct correlation with the clinical form (r ≥ 0.77). The AUROC value to define the presence of fibrosis was 0.92 and for significant fibrosis was 0.79, with cut-offs of 6.1 kPa and 8.9 kPa, respectively.

CONCLUSIONS

In this study, the TE was effective in the diagnosis of schistosomal fibrosis, being able to identify the advanced forms of the disease and thus predict the risk of clinical complications in endemic regions.

Liver stiffness is able to differentiate hepatosplenic Schistosomiasis mansoni from liver cirrhosis and spleen stiffness may be a predictor of variceal bleeding in hepatosplenic schistosomiasis

BACKGROUND

Ultrasonography is limited for differentiating portal hypertension due to liver cirrhosis from that secondary to hepatosplenic schistosomiasis (HSS). We aimed to investigate the role of transient elastography (TE) in differentiating HSS mansoni from cirrhosis and the factors associated with liver and spleen stiffness (LS and SS) in HSS.

METHOD

A cross-sectional study was conducted including patients with HSS mansoni (n=29) and liver cirrhosis due to non-alcoholic steatohepatitis (n=23). All patients underwent TE and those with HSS were assessed by the Niamey protocol.

RESULTS

HSS subjects presented lower median LS (9.6 vs 21.3 Kpa, p<0.001) and liver controlled attenuation parameter (229 vs 274 dB/m, p=0.010) than cirrhosis subjects, in addition to higher SS (73.5 vs 42.2 Kpa, p=0.002). The area under the receiver operating characteristic curve for detecting cirrhosis by LS was 0.947 (95% CI 0.89 to 1.00, p<0.001), with an optimal cut-off of 11.75 Kpa. In HSS subjects, higher SS was associated with the presence of the following: diabetes mellitus (p=0.036), metabolic syndrome (p=0.043), esophageal varices (p=0.001), portal vein thrombosis (p=0.047) and previous variceal bleeding (p=0.011). In HSS patients without portal vein thrombosis, variceal bleeding was associated with higher SS (p=0.018). Niamey categories were not associated with LS (p=0.676) or SS (p=0.504).

CONCLUSION

TE can play a role in differentiating HSS from cirrhosis, especially by LS. SS may be further investigated for predicting complications in HSS.

Schistosomiasis Pulmonary Arterial Hypertension

Pulmonary arterial hypertension (PAH) is a disease of the lung blood vessels that results in right heart failure. PAH is thought to occur in about 5% to 10% of patients with hepatosplenic schistosomiasis, particularly due to S. mansoni. The lung blood vessel injury may result from a combination of embolization of eggs through portocaval shunts into the lungs causing localized Type 2 inflammatory response and vessel remodeling, triggering of autonomous pathology that becomes independent of the antigen, and high cardiac output as seen in portopulmonary hypertension. The condition is likely underdiagnosed as there is little systematic screening, and risk factors for developing PAH are not known. Screening is done by echocardiography, and formal diagnosis requires invasive right heart catheterization. Patients with Schistosoma-associated PAH show reduced functional capacity and can be treated with pulmonary vasodilators, which improves symptoms and may improve survival. There are animal models of this disease that might help in understanding disease pathogenesis and identify novel targets to screen and treatment. Pathogenic mechanisms include Type 2 immunity and activation and signaling in the TGF-β pathway. There are still major uncertainties regarding Schistosoma-associated PAH development, course and treatment.

2-D Shear Wave Elastography for the Evaluation of Liver Fibrosis in Hepatosplenic Schistosomiasis: Reliability of a Single Measurement and Inter-Hepatic Lobe Variability

Data on liver and spleen stiffness by 2-D shear wave elastography (2-D SWE) in hepatosplenic schistosomiasis (HES) remain scarce. We aimed to assess the correlation between single to multiple measurements of liver and spleen stiffness and to evaluate inter-hepatic lobe variability of liver stiffness measurement (LSM) using 2-D SWE in HES patients. Liver and spleen elastography were performed in HES patients in this cross-sectional study. A total of four stiffness measurements were performed in the right lobe (RL), left lobe (LL), and spleen. The correlation between the first measurement and the median of four measurements was assessed. Liver stiffness measurement of both hepatic lobes was compared. Twenty-six HES patients were included. Liver stiffness measurement was higher in the left than in the right hepatic lobe (17.9 kPa [11.3-92.0] versus 14.9 kPa [5.6-44.4]; P = 0.019). The first measurement was similar to the median of the four measurements for the RL (14.6 [5.6-60.8] versus 14.9 kPa [5.6-44.4]; P = 0.87), LL (17.4 [8.0-128.1] versus 17.9 kPa [11.3-92.0]; P = 0.54), and spleen (50.5 [10.0-157.0] versus 55.7 kPa [19.1-119.4]; P = 0.48). An excellent correlation between the first measurement and the median of four measurements for the RL (r = 0.93; P < 0.001), LL (r = 0.88; P < 0.001), and spleen (r = 0.89; P < 0.001) was observed. In HES, LSM of the LL seems to be higher than that of the right hepatic lobe. Considering the excellent correlation between the first measurement and the median of four measurements in both hepatic lobes and spleen, a single measurement would be sufficient to evaluate liver and splenic stiffness in patients with HES.

Granulomas in parasitic diseases: the good and the bad

Parasitic diseases affect more than one billion people worldwide, and most of them are chronic conditions in which the treatment and prevention are difficult. The appearance of granulomas, defined as organized and compact structures of macrophages and other immune cells, during various parasitic diseases is frequent, since these structures will only form when individual immune cells do not control the invading agent. Th2-typering various parasitic diseases are frequent, since these structures will only form when individual immune cells do not control the invading agent. The characterization of granulomas in different parasitic diseases, as well as recent findings in this field, is discussed in this review, in order to understand the significance of the granuloma and its modulation in the host-parasite interaction and in the immune, pathological, and parasitological aspects of this interaction. The parasitic granulomatous diseases granulomatous amebic encephalitis, toxoplasmosis, leishmaniasis, neurocysticercosis, and schistosomiasis mansoni are discussed as well as the mechanistic and dynamical aspects of the infectious granulomas.

Ultrasound evaluation of schistosomiasis-related morbidity among the Xakriabá people in the state of Minas Gerais, Brazil

Objective

To use ultrasound to investigate the morbidity related to schistosomiasis in the Xakriabá indigenous population.

Materials and Methods

This was a field-based census study conducted in the territory of the Xakriabá people. A total of 166 individuals were invited, and 148 (≤ 77 years of age) agreed to participate. Most participants underwent abdominal ultrasound, physical examination, and stool examination. Mann-Whitney U and chi-square tests were used for comparisons. We determined risk by calculating odds ratio (OR) and performed logistic regression analysis.

Results

Schistosoma mansoni eggs were found in 31 (26.7%) of the 116 stool samples examined, 22 (70.9%) of the 31 being from individuals 4-16 years of age. The median count was 144 eggs/g of feces (interquartile range, 264). Of the 105 participants examined with ultrasound, 68 (64.8%) had hepatomegaly (left lobe), 6 (5.7%) had splenomegaly, and 4 (3.8%) had portal hypertension. Egg-positive stool samples were more common in those with an enlarged left lobe (OR = 3.4; 95% confidence interval (CI): 1.1-11.2; p = 0.043). Periportal fibrosis was found in 30 participants (28.6%), of whom 9 (30%) had pattern C, 10 (33.3%) had pattern D, and 11 (36.7%) had pattern Dc. Age was the only independent risk factor for fibrosis (p = 0.007). Fibrosis was up to nine-fold more common in alcohol drinkers than in nondrinkers (OR = 9.28; 95% CI: 2.60-33.06; p < 0.001). Among the 138 participants in whom the clinical form was classified, the chronic hepatic form was identified in 54 (39.1%), of whom 32 (59.2%) were under 30 years of age and one (1.8%) was hepatosplenic.

Conclusion

Schistosomiasis in the Xakriabá population is characterized by a high frequency of egg-positive stool samples, predominantly in children/adolescents, and by chronic hepatic form in the young, especially among alcohol drinkers.

Clinical and Preclinical Imaging of Hepatosplenic Schistosomiasis

Schistosomiasis, a neglected tropical disease, is a major cause of chronic morbidity and disability, and premature death. The hepatosplenic form of schistosomiasis is characterized by hepatosplenomegaly, liver fibrosis, portal hypertension, and esophageal varices, whose rupture may cause bleeding and death. We review currently available abdominal imaging modalities and describe their basic principles, strengths, weaknesses, and usefulness in the assessment of hepatosplenic schistosomiasis (HSS). Advanced imaging methods are presented that could be of interest for hepatosplenic schistosomiasis evaluation by yielding morphological, functional, and molecular parameters of disease progression. We also provide a comprehensive view of preclinical imaging studies and current research objectives such as parasite visualization in hosts, follow-up of the host's immune response, and development of noninvasive quantitative methods for liver fibrosis assessment.

Sound Around the World: Ultrasound for Tropical Diseases

Ultrasound for diagnosis and staging of schistosomiasis and echinococcosis have paved the way over the past several decades for the application of ultrasound in tropical diseases. Until recently, the size and cost of ultrasound systems limited the application in low-resource settings. The increase in portable ultrasound systems has given more clinicians access to ultrasound, and clinically based protocols for the care of patients have emerged, such as focused assessment with sonography for HIV/TB and tropical cardiac ultrasound. This article explores the history and current use of ultrasound in these diseases and highlights their application in the care of patients.

Correlation between the values of circulating blood elements with the size of spleen in the presence of schistosomal splenomegaly

PURPOSE

To evaluate a possible relationship between the size of the spleen and values of circulating blood elements in patients with schistosomatic splenomegaly.

METHODS

ixty one patients with hepatosplenic schistosomiasis mansoni underwent a clinical exam and peripheral venous blood was collected for a hemogram. The erythrocyte, hemoglobin, hematocrit, leukocyte, and platelet values were determined. All patients underwent abdominal ultrasound to measure the spleen. The hematological test results were compared to the size of the spleen.

RESULTS

The size of the spleen varied from 14.0 to 28.4 (19.9 ± 3.7) cm according to the ultrasound image. Thrombocytopenia was observed 58 (95%) patients, leukopenia in 55 (90%) patients, and anemia in 32 (52.4%) patients. Leukopenia was proportional to splenomegaly.

CONCLUSION

Schistosomal splenomegaly leads to leukopenia in direct proportion to the size of the spleen.

X-ray micro-computed tomography (μCT): an emerging opportunity in parasite imaging

X-ray micro-computed tomography (μCT) is a technique which can obtain three-dimensional images of a sample, including its internal structure, without the need for destructive sectioning. Here, we review the capability of the technique and examine its potential to provide novel insights into the lifestyles of parasites embedded within host tissue. The current capabilities and limitations of the technology in producing contrast in soft tissues are discussed, as well as the potential solutions for parasitologists looking to apply this technique. We present example images of the mouse whipworm Trichuris muris and discuss the application of μCT to provide unique insights into parasite behaviour and pathology, which are inaccessible to other imaging modalities.

Thrombocytopenia as a marker of liver steatosis in a low-endemic area for schistosomiasis mansoni

Introduction:

Thrombocytopenia is commonly found in patients living in highly endemic areas for Schistosoma mansoni. Recently, different degrees of liver steatosis have also been associated with low platelet counts worldwide. We investigated the association of platelet counts with hepatosplenic schistosomiasis and with liver steatosis in an area of low prevalence of schistosomiasis in Brazil.

Method:

Pains, a city in the state of Minas Gerais, Brazil, had a population of 8,307 inhabitants and a schistosomiasis prevalence of 8%. Four micro-areas comprising 1,045 inhabitants were selected for this study. Blood sample was collected and a complete blood count (CBC) was performed. Eighty-seven (87) patients had low platelet counts (group 1 - 8.3%) and 94 volunteers presenting normal CBC were randomized (group 2 - 8.9%). They underwent clinical and ultrasound examinations. Liver steatosis was determined as either present or absent using abdominal ultrasound. A spleen > 12 cm in length, measured by ultrasound (US), was considered to be increased. Data collected were analyzed using SPSS software version 19.0.

Results:

Twenty-two patients (22/25.3%) in group 1 had liver steatosis compared with 11 volunteers (11.7%) in group 2 (p=0.02). Hepatosplenic schistosomiasis was diagnosed in two patients (p>0.05).

Conclusion:

Thrombocytopenia was not a good marker of hepatosplenic schistosomiasis mansoni in a low prevalence area in Brazil. Liver steatosis was associated with thrombocytopenia in our study.

There is no evident correlation between interleukin-10 gene polymorphisms and periportal fibrosis regression after specific treatment

INTRODUCTION:

We evaluated the associations between interleukin-10 (IL-10) gene polymorphisms -G1082A/-C819T/-C592A and periportal fibrosis regression after specific treatment for schistosomiasis.

METHODS:

This retrospective cohort study involved 125 Brazilian patients infected with Schistosomiasis mansoni, who were followed up for 2 years after specific treatment to estimate the probability of periportal fibrosis regression.

RESULTS:

There was no evidence of associations between IL-10 polymorphisms and periportal fibrosis regression after treatment.

CONCLUSIONS:

There was no evidence of associations between gene promoter polymorphisms of IL-10 and the regression of periportal fibrosis in this Brazilian population.

In Vivo MRI Assessment of Experimental Schistosomiasis

A new study using magnetic resonance imaging (MRI) evaluated successfully the transverse relaxation time T2 as a non-invasive imaging biomarker for monitoring hepatic fibrogenesis in schistosomiasis. However, there are some drawbacks that need special attention. This preliminary data opens new opportunities to understand and monitor liver fibrosis in schistosomiasis and other fibrogenic diseases.

In Vivo MRI Assessment of Hepatic and Splenic Disease in a Murine Model of Schistosomiasis [corrected]

BACKGROUND

Schistosomiasis (or bilharzia), a major parasitic disease, affects more than 260 million people worldwide. In chronic cases of intestinal schistosomiasis caused by trematodes of the Schistosoma genus, hepatic fibrosis develops as a host immune response to the helminth eggs, followed by potentially lethal portal hypertension. In this study, we characterized hepatic and splenic features of a murine model of intestinal schistosomiasis using in vivo magnetic resonance imaging (MRI) and evaluated the transverse relaxation time T2 as a non-invasive imaging biomarker for monitoring hepatic fibrogenesis.

METHODOLOGY/PRINCIPAL FINDINGS

CBA/J mice were imaged at 11.75 T two, six and ten weeks after percutaneous infection with Schistosoma mansoni. In vivo imaging studies were completed with histology at the last two time points. Anatomical MRI allowed detection of typical manifestations of the intestinal disease such as significant hepato- and splenomegaly, and dilation of the portal vein as early as six weeks, with further aggravation at 10 weeks after infection. Liver multifocal lesions observed by MRI in infected animals at 10 weeks post infection corresponded to granulomatous inflammation and intergranulomatous fibrosis with METAVIR scores up to A2F2. While most healthy hepatic tissue showed T2 values below 14 ms, these lesions were characterized by a T2 greater than 16 ms. The area fraction of increased T2 correlated (rS = 0.83) with the area fraction of Sirius Red stained collagen in histological sections. A continuous liver T2* decrease was also measured while brown pigments in macrophages were detected at histology. These findings suggest accumulation of hematin in infected livers.

CONCLUSIONS/SIGNIFICANCE

Our multiparametric MRI approach confirms that this murine model replicates hepatic and splenic manifestations of human intestinal schistosomiasis. Quantitative T2 mapping proved sensitive to assess liver fibrogenesis non-invasively and may therefore constitute an objective imaging biomarker for treatment monitoring in diseases involving hepatic fibrosis.

Severe liver fibrosis caused by Schistosoma mansoni: management and treatment with a transjugular intrahepatic portosystemic shunt

Liver diseases are common in inhabitants and migrants of tropical countries, where the liver can be exposed not only to toxins but also to many viral, bacterial, fungal, and parasitic infections. Schistosomiasis--a common parasitic infection that affects at least 240 million people worldwide, mostly in Africa--is regarded as the most frequent cause of liver fibrosis worldwide. We present a case of a 19-year-old male refugee from Guinea with recurrent oesophageal variceal bleeding due to schistosomal liver fibrosis refractory to endoscopic therapy. This case was an indication for portosystemic surgery, which is a highly invasive non-reversible intervention. An alternative, less invasive, reversible radiological procedure, used in liver cirrhosis, is the placement of a transjugular intrahepatic portosystemic shunt (TIPS). After thorough considerations of all therapeutic options we placed a TIPS in our patient. In more than 3 years of observation, he is clinically well apart from one episode of hepatic encephalopathy related to an acute episode of viral gastroenteritis. Bleeding from oesophageal varices has not recurred. In this Grand Round, we review the diagnostic approaches and treatment options for portal hypertension due to schistosomal liver fibrosis.

Angiografic and pressoric changes determined by splenectomy with left gastric vein ligature in mansoni schistosomiasis

BACKGROUND

In hepatosplenic schistosomiasis occurs diffuse hepatic fibrosis associated with venous congestion of the portal system resulting in hepatosplenomegaly. It can produce digestive hemorrhage caused by rupture of esophageal and stomach varices or peptic gastroduodenal mucosal lesions.

AIM

To study the effects of splenectomy and ligature of the left gastric vein on portohepatic hemodynamics.

METHOD

Twenty-three patients with hepatosplenic schistosomiasis mansoni were studied before and about two weeks after operation through angiographic diameter of the common and proper hepatic artery, splenic artery, superior mesenteric artery, portal vein, superior mesenteric vein and left gastric vein. The pressures of the inferior vena cava and central venous pressure, free hepatic vein, the hepatic sinusoidal and occluded vein were measured.

RESULTS

The splenectomy and ligature of the left gastric vein determined low morbidity and null mortality. It determined significant addition to the following variables: diameters of the common and proper hepatic artery; diameter of the superior mesenteric vein. It determined non significant increase on the following measurements: right atrial pressure and diameter of the superior mesenteric artery. It determined non significant decrease to the following variables: inferior vena cava pressure; free hepatic vein pressure; occluded hepatic vein pressure; sinusoidal pressure, diameter of the portal vein.

CONCLUSION

Splenectomy and ligature of the left gastric vein do not determine portal hemodynamic changes capable of breaking the functional hemodinamic balance that characterizes the hepatosplenic mansoni schistosomiasis.

Chronic hepatitis B and liver schistosomiasis: a deleterious association

BACKGROUND

Chronic hepatitis B (CHB) and schistosomiasis are prevalent in several countries, but the impact of this association is unknown. We aimed to investigate the prevalence and morbidity of this co-infection in Minas Gerais, an endemic area of schistosomiasis in Brazil.

METHODS

In total, 406 adults with CHB (HBsAg positive >6 months) were included in a cross-sectional study. CHB was classified as replicative (HBV DNA ≥ 2.000 IU/ml), and low replicative or inactive hepatitis B carriers (HBV DNA <2.000 IU/ml). Schistosomiasis was confirmed by epidemiological and clinical records. Liver biopsies were scored by METAVIR. The risk of severe fibrosis was estimated by multivariate analysis.

RESULTS

Of the 406 patients, 64.8% (263) were male, and the median age was 45 years (IQR 35-54). In total, 57.9% (235) had replicative CHB, and 31.5% (128) had cirrhosis. Schistosoma mansoni was confirmed in 30.5% (124) patients, 81.5% (101) of which were male with a median age of 47 years (IQR 39.5-54). Of the co-infected patients, 61.3% (76) and 38.7% (48) had replicative and inactive CHB, respectively. Schistosomal portal fibrosis (PF) was detected in 69.4% (86/124) patients. Patients with replicative CHB and schistosomal PF had more advanced fibrosis and severe inflammation compared with patients without schistosomal PF (80.8% vs 43.6% for METAVIR F3-F4, p<0.01; 64.0% vs 39.8% for METAVIR A2-A3, p < 0.01). Age >50 years (OR = 1.10; 95% CI 1.06-1.14, p<0.001), male gender (OR = 2.61, 95% CI 1.12-6.09, p = 0.03), schistosomal PF (OR = 4.56, 95% CI 2.10-9.91, p<0.001) and alcoholism (OR = 2.46, 95% CI 1.16-5.19, p = 0.02) were independently associated with cirrhosis.

CONCLUSIONS

The association between replicative CHB and schistosomal PF can be a risk factor for more severe liver disease, which can result in deleterious outcomes for patients from endemic areas.

The WHO ultrasonography protocol for assessing hepatic morbidity due to Schistosoma mansoni. Acceptance and evolution over 12 years

The aim of this study is to review the worldwide acceptance of the World Health Organization (WHO) ultrasound protocol for assessing hepatosplenic morbidity due to Schistosoma mansoni since its publication in 2000. A PubMed literature research using the keywords "schistosomiasis and ultrasound," "schistosomiasis and ultrasonography," and "S. mansoni and ultrasound" from 2001 to 2012 was performed. Case reports, reviews, reports on abnormalities due to parasites other than S. mansoni, organ involvement other than the human liver, and reports where ultrasound method was not described were excluded. Six studies were retrieved from other Brazilian sources. Sixty studies on 37,424 patients from 15 countries were analyzed. The WHO protocol was applied with increasing frequency from 43.75% in the years 2001 to 2004 to 84.61% in 2009 to 2012. Results obtained using the pictorial image pattern approach of the protocol are reported in 38/41 studies, whereas measurements of portal branch walls were applied in 19/41 and results reported in 2/41 studies only. The practical usefulness of the pictorial approach of the WHO protocol is confirmed by its wide acceptance. This approach alone proved satisfactory in terms of reproducibility, assessment of evolution of pathology, and comparability between different settings. The measurements of portal branches, also part of the protocol, may be omitted without losing relevant information since results obtained by these measurements are nonspecific. This would save resources by reducing the time required for each examination. It is also more feasible for examiners who are not specialized in medical imaging. As with all protocols, incipient liver fibrosis is difficult to distinguish from normal ultrasound findings of the liver. The ability of this protocol to predict complications in severe cases should be further evaluated in a higher number of patients.

Haematological and biochemical characteristics of the splenic effluent blood in schistosomal patients undergoing splenectomy

OBJECTIVE

To assess hematological and biochemical features of splenic effluent blood and their influence on the rise of hematological values after splenectomy.

METHODS

we studied 20 patients undergoing surgical treatment for schistosomatic portal hypertension. We collected blood samples for CBC, coagulation, bilirubin and albumin in the splenic vein (perioperative) and peripheral blood (immediately pre and postoperative periods).

RESULTS

the splenic blood showed higher values of red blood cells, hemoglobin, hematocrit, platelet count, total leukocytes, neutrophils, lymphocytes, monocytes, eosinophils and basophils, as well as reduction of laboratory coagulation parameters in relation to peripheral blood collected preoperatively. In the postoperative peripheral blood there was an increase in the overall leukocytes and in their neutrophil component, and decreased levels of basophils, eosinophils and lymphocytes. The other postoperative variables of complete blood count and coagulation tests were not different compared with the splenic blood. The albumin values were lower postoperatively when compared to preoperative and splenic blood. There were higher values of direct bilirubin in the postoperative period when compared with the preoperative and splenic blood. Postoperative indirect bilirubin was lower compared to its value in the splenic blood.

CONCLUSION

hematological and biochemical values of splenic effluent blood are higher than those found in peripheral blood in the presence of schistosomal splenomegaly. However, the splenic blood effluent is not sufficient to raise the blood levels found after splenectomy.

Revisiting the concept of hepatosplenic schistosomiasis and its challenges using traditional and new tools

Different aspects of hepatosplenic schistosomiasis are revisited here. Manson's schistosomiasis causes periportal fibrosis and portal hypertension in approximately 6% of infected subjects, usually with preservation of their hepatic function. The assessment of liver involvement is of major importance in determining the prognosis and risk of complications from schistosomiasis, such as upper digestive bleeding secondary to variceal rupture. For many years, the diagnosis of hepatosplenic schistosomiasis and liver fibrosis was made by abdominal palpation and the finding of liver and/or spleen enlargement. However, there is no consensus regarding the clinical parameters of the liver and spleen to be considered in this physical evaluation. For the last three decades, abdominal ultrasound (US) has become the best imaging technique to evaluate liver fibrosis caused by schistosomiasis mansoni. However, US is a subjective procedure and is therefore examiner-dependent. Magnetic resonance imaging (MRI) findings have provided valuable information in addition to ultrasound and clinical examination. The combination of a comprehensive history and physical examination, basic laboratory tests (a stool examination for Schistosoma mansoni eggs and a blood cell count), biomarkers for liver fibrosis/portal hypertension and imaging methods seem to offer the best approach for evaluating patients with this disease. In situations where research is involved or in patients with severe disease, MRI may be considered.

Evolutional profile of the esophageal varices after splenectomy associated with ligation of the left gastric vein and sclerotherapy in schistosomal portal hypertension

BACKGROUND

The schistosomiasis affects 200 million people in 70 countries worldwide. It is estimated that 10% of those infected will develop hepatosplenic status and of these, 30% will progress to portal hypertension and esophagogastric varices, whose expression is through gastrointestinal bleeding with significant mortality in the first bleeding episode. Multiple surgical techniques have been developed to prevent re-bleeding.

AIM

To evaluate the evolutional profile of esophageal varices after splenectomy + ligation of the left gastric vein associated with endoscopic sclerotherapy in schistosomal portal hypertension.

METHODS

Prospective and observational study including schistosomiasis patients with previous history of upper digestive hemorrhage and underwent to splenectomy + ligation of the left gastric vein and sclerotherapy. The variables were: evolutional profile of esophageal varices before and after surgery and re-bleeding rate.

RESULTS

The sample included 30 patients, 15 patients for each gender. The age ranged from 19 to 74 years (median = 43 years). There was a reduction in the degree, caliber and red spots in all patients (p< 0.05). The eradication of varices with sclerotherapy was achieved in 86.7% and with surgery alone in 15.4%. The mean follow-up was 28 months, ranging from two to 76 months. Were carried from one to seven sessions of sclerotherapy and the average was three per patient to eradicate varices. Four (13.3%) did not complete the follow-up. The re-bleeding rate was 16.7%.

CONCLUSION

There was a reduction of the degree, caliber and red spots of esophageal varices in all patients.

Macrophage-derived Hedgehog ligands promotes fibrogenic and angiogenic responses in human schistosomiasis mansoni

BACKGROUND

Schistosomiasis mansoni is a major cause of portal fibrosis and portal hypertension. The Hedgehog pathway regulates fibrogenic repair in some types of liver injury.

AIMS

Determine if Hedgehog pathway activation occurs during fibrosis progression in schistosomiasis and to determine if macrophage-related mechanisms are involved.

METHODS

Immunohistochemistry was used to characterize the cells that generate and respond to Hedgehog ligands in 28 liver biopsies from patients with different grades of schistosomiasis fibrosis staged by ultrasound. Cultured macrophages (RAW264.7 and primary rat Kupffer cells) and primary rat liver sinusoidal endothelial cells (LSEC) were treated with schistosome egg antigen (SEA) and evaluated using qRT-PCR. Inhibition of the Hedgehog pathway was used to investigate its role in alternative activation of macrophages (M2) and vascular tube formation.

RESULTS

Patients with schistosomiasis expressed more ligands (Shh and Ihh) and target genes (Patched and Gli2) than healthy individuals. Activated LSEC and myofibroblasts were Hedgehog responsive [Gli2(+)] and accumulated in parallel with fibrosis stage (P < 0.05). Double IHC for Ihh/CD68 showed that Ihh(+) cells were macrophages. In vitro studies demonstrated that SEA-stimulated macrophages to express Ihh and Shh mRNA (P < 0.05). Conditioned media from such macrophages induced luciferase production by Shh-LightII cells (P < 0.001) and Hedgehog inhibitors blocked this effect (P < 0.001). SEA-treated macrophages also up-regulated their own expression of M2 markers, and Hh pathway inhibitors abrogated this response (P < 0.01). Inhibition of the Hedgehog pathway in LSEC blocked SEA-induced migration and tube formation.

CONCLUSION

SEA stimulates liver macrophages to produce Hh ligands, which promote alternative activation of macrophages, fibrogenesis and vascular remodelling in schistosomiasis.