Hepatic artery resistance index at doppler ultrasonography is a useful parameter of hepatic graft-vs-host disease after allogeneic stem cell transplantation

Hepatic graft-versus-host disease: what we know, when to biopsy, and how to diagnose

Graft-versus-host disease (GVHD) is one of the serious complications that may develop after hematopoietic cell transplantation (HCT), for hematologic malignancies, solid organ transplantation, and other hematologic disorders. GVHD develops due to T lymphocytes present in the graft attacking the host antigens, which results in tissue damage. A significant number of HCT patients develop acute or chronic GVHD, which may affect multiple organs including the liver. The diagnosis of hepatic GVHD (hGVHD) is challenging as many other conditions in HCT patients may lead to liver dysfunction. Particularly challenging among the various conditions that give rise to liver dysfunction is differentiating sinusoidal obstruction syndrome and drug-induced liver injury (DILI) from hGVHD on clinical grounds and laboratory tests. Despite the minimal risks involved in performing a liver biopsy, the information gleaned from the histopathologic changes may help in the management of these very complex patients. There is a spectrum of histologic features found in hGVHD, and most involve histopathologic changes affecting the interlobular bile ducts. These include nuclear and cytoplasmic abnormalities including dysmorphic bile ducts, apoptosis, and cholangiocyte necrosis, among others. The hepatitic form of hGVHD typically shows severe acute hepatitis. With chronic hGVHD, there is progressive bile duct loss and eventually fibrosis. Accurate diagnosis of hGVHD is paramount so that timely treatment and management can be initiated. Techniques to prevent and lower the risk of GVHD from developing have recently evolved. If a diagnosis of acute GVHD is made, the first-line of treatment is steroids. Recurrence is common and steroid resistance or dependency is not unusual in this setting. Second-line therapies differ among institutions and have not been uniformly established. The development of GVHD, particularly hGVHD, is associated with increased morbidity and mortality.

Role of Multiparametric Ultrasound in Evaluating Hepatic Acute Graft-versus-Host Disease: An Animal Study

OBJECTIVE

Hepatic acute graft-versus-host disease (aGVHD) is a serious complication of allogeneic hematopoietic stem cell transplantation (allo-HSCT) and is one of the leading causes of early non-recurrent death. The current diagnosis is based mainly based on clinical diagnosis, and there is a lack of non-invasive quantitative diagnosis methods. We propose a multiparametric ultrasound (MPUS) imaging method and explore its effectiveness in evaluating hepatic aGVHD.

METHODS

In this study, 48 female Wistar rats were used as receptors and 12 male Fischer 344 rats were used as donors for allo-HSCT to establish aGVHD models. After transplantation, 8 rats were randomly selected for ultrasonic examination weekly, including color Doppler ultrasound, contrast-enhanced ultrasound (CEUS) and shear wave dispersion (SWD) imaging. The values of nine ultrasonic parameters were obtained. Hepatic aGVHD was subsequently diagnosed by histopathological analysis. A classification model for predicting hepatic aGVHD was established using principal component analysis and support vector machines.

RESULTS

According to the pathological results, the transplanted rats were categorized into the hepatic aGVHD and non-GVHD (nGVHD) groups. All parameters obtained by MPUS differed statistically between the two groups. The first three contributing percentages of principal component analysis results were resistivity index, peak intensity and shear wave dispersion slope, respectively. The accuracy of classifying aGVHD and nGVHD using support vector machines reached 100%. The accuracy of the multiparameter classifier was significantly higher than that of the single parameter.

CONCLUSION

The MPUS imaging method has proven to be useful in detecting hepatic aGVHD.

Current approach to early gastrointestinal and liver complications of hematopoietic stem cell transplantation

The gastrointestinal (GI) system is one of the most commonly affected sites during a hematopoietic stem cell transplantation (HSCT) due to toxicities of preparative regimens, the accompanying immunodeficiency, and organ damage caused by graft versus host disease. In this review, we focus on early GI and liver complications following autologous (auto-) and allogeneic (allo-) HSCT and clarify both the risk factors and therapeutic strategies. Early GI and liver complications associated with HSCT remain challenging issues. Despite the improvements in this field during the last decade, treatments for these complications still place a significant burden on both patients and the physicians treating these patients. GI and liver complications remain some of the causes of mortality associated with HSCT. For practicing hematologists, oncologists, and gastroenterologists in this field, the awareness and early diagnosis of the GI complications remain important factors to obtain optimal outcomes in this patient population.

Doppler parameters of the maternal hepatic artery blood flow in normal pregnancy: maternal hepatic artery blood flow in normal pregnancy

OBJECTIVE

Objective of our study was to evaluate changes in Doppler resistance indices in the common hepatic artery during normal pregnancy.

STUDY DESIGN

Cross-sectional study included 210 healthy pregnant women gestational age 6-40 weeks, 40 healthy non-pregnant women and 30 women after delivery. We divided all pregnant women by pregnancy trimester. We registered pulsatility index (PI) and resistive index (RI) in the common hepatic artery and compared the evaluated values among non-pregnant women and women in first, second and third trimester and post partum and tested correlation of both parameters with gestational age. Statistical analysis was done by Chi square test, one-way ANOVA followed by post-hoc test and two-tailed Pearson and Spearman correlation. The difference was considered to be significant if p<0.05.

RESULTS

We found lower values of PI and RI in the third trimester compared to control group and first and second trimester (p<0.01). There is negative correlation between the values of PI and RI with the gestation (p<0.01).

CONCLUSION

Hepatic artery resistance indices decrease during the third trimester of pregnancy. This decrease may be the result of systemic arterial vasodilatation in normal pregnancy. The arterial resistance indices may be more useful for the evaluation of liver blood flow over the total blood flow as they are more reliable, being angle independent, easier to obtain, reflect vascular changes and might help in quick orientation about liver blood flow in pregnancies complicated by preeclampsia and HELLP syndrome. Our study is a pilot one, and further studies are needed to establish nomograms for the PI and RI during the gestation.

Value of liver elastography and abdominal ultrasound for detection of complications of allogeneic hemopoietic SCT

Hepatic complications contribute to morbidity and mortality after allogeneic hemopoietic SCT. Liver Doppler ultrasound and elastography represent promising methods for pretransplant risk assessment and early detection of complications. Ultrasound (liver and spleen size, liver perfusion) and elastography (transient elastography (TE); right liver lobe acoustic radiation force impulse imaging (r-ARFI); left liver lobe ARFI (l-ARFI)) were prospectively evaluated in patients with indications for allo-SCT. Measurements were performed before and repeatedly after SCT. Results were compared with the incidence of life-threatening complications and death during the first 150 days after SCT. Of 59 included patients, 16 suffered from major complications and 9 of them died within the follow-up period. At baseline, liver and spleen size, liver perfusion, TE and r-ARFI did not differ significantly between patients with and without severe complications. In contrast, l-ARFI was significantly elevated in patients who later developed severe complications (1.58±0.30 m/s vs 1.37±0.27 m/s, P=0.030). After SCT, l-ARFI values remained elevated and TE showed increasing liver stiffness in patients with complications. The value of conventional liver ultrasound for prediction of severe SCT complications is limited. Increased values for TE and l-ARFI are associated with severe SCT complications and demand further evaluation.