Hepatic Sinusoidal Dilatation: A Review of Causes With Imaging-Pathologic Correlation

Hepatic sinusoidal congestion associated with inotuzumab therapy in patients with B-cell acute lymphoblastic leukemia, a proposal for a new clinical entity: Calicheamicin syndrome

Inotuzumab (InO) is an anti-CD22 immunoconjugate for patients with relapsed or refractory CD22 positive B-cell acute lymphoblastic leukemia (B-ALL). Liver toxicity is a recognized side effect of InO, including sinusoidal obstruction syndrome (SOS), but is not fully understood. This study describes a new aspect of InO-induced hepatotoxicity by outlining six patients who developed abnormal liver function tests (LFTs) and thrombocytopenia, with liver biopsies showing sinusoidal congestion without evidence of SOS. Liver biopsies were obtained from all six patients and LFTs were monitored before initiating InO treatment, during treatment, and after discontinuing treatment. All six patients experienced abnormal LFTs at a median of 15 days after the last dose of InO and improvement in LFTs at a median of 17 days after discontinuing InO. Initial baseline AST, ALT, ALP, and total bilirubin values prior to InO therapy ranged from 10-45 U/L, 10-45 U/L, 60-207 U/L, and 0.2-0.9 mg/dL respectively and increased up to 2 to 4 times the upper limit of normal after completing varying cycles of InO with hepatotoxicity grades ranging from 1-2. LFTs returned to 1 to 1.5 times the upper limit of normal after discontinuing InO. The patients' liver biopsies all demonstrated different levels of hepatic sinusoidal congestion (HSC) without evidence of SOS. This study provides new evidence describing HSC, where we hypothesize that InO induced hepatotoxicity are due to calicheamicin. We propose a new clinical entity called "calicheamicin syndrome" with its quadriad components: History of using InO or GO, elevated LFTs, thrombocytopenia, and abnormal liver imaging.

Hepatic Sinusoidal Disorders

Hepatic sinusoids are highly specialized microcirculatory conduits within the hepatic lobules that facilitate liver functions. The sinusoids can be affected by various disorders, including sinusoidal dilatation, sinusoidal obstruction syndrome (SOS), sinusoidal cellular infiltration, perisinusoidal infiltration, and endothelial neoplasms, such as hemangioendothelioma and angiosarcoma. While these disorders, particularly SOS and neoplasms, can be life threatening, their clinical manifestation is often nonspecific. Patients may present with right upper quadrant pain, jaundice, hepatomegaly, ascites, splenomegaly, and unexplained weight gain, although the exact manifestation depends on the cause, severity, and duration of the disease. Ultimately, invasive tests may be necessary to establish the diagnosis. A comprehensive understanding of imaging manifestations of various sinusoidal disorders contributes to early diagnosis and can help radiologists detect subclinical disease. Additionally, specific imaging features may assist in identifying the cause of the disorder, leading to a more focused and quicker workup. For example, a mosaic pattern of enhancement of the liver parenchyma is suggestive of sinusoidal dilatation; peripheral and patchy reticular hypointensity of the liver parenchyma on hepatobiliary MR images is characteristic of SOS; and associated diffuse multiple hyperintensities on diffusion-weighted images may be specific for malignant sinusoidal cellular infiltration. The authors provide an overview of the pathogenesis, clinical features, and imaging appearances of various hepatic sinusoidal disorders, with a special emphasis on SOS. ©RSNA, 2024 Supplemental material is available for this article.

Histologic Findings of Sinusoidal Dilatation and Congestion in Liver Grafts Do Not Correlate with Hepatic Venous Anastomotic Gradients

PURPOSE

Hepatic venous transplant anastomotic pressure gradient measurement and transjugular liver biopsy are commonly used in clinical decision-making in patients with suspected anastomotic hepatic venous outflow obstruction. This investigation aimed to determine if sinusoidal dilatation and congestion on histology are predictive of hepatic venous anastomotic outflow obstruction, and if it can help select patients for hepatic vein anastomosis stenting.

MATERIALS AND METHODS

This is a single-center retrospective study of 166 transjugular liver biopsies in 139 patients obtained concurrently with transplant venous anastomotic pressure gradient measurement. Demographic characteristics, laboratory parameters, procedure and clinical data, and histology of time-zero allograft biopsies were analyzed.

RESULTS

No relationship was found between transplant venous anastomotic pressure gradient and sinusoidal dilatation and congestion (P = 0.92). Logistic regression analysis for sinusoidal dilatation and congestion confirmed a significant relationship with reperfusion/preservation injury and/or necrosis of the allograft at time-zero biopsy (OR 6.6 [1.3-33.1], P = 0.02).

CONCLUSION

There is no relationship between histologic sinusoidal dilatation and congestion and liver transplant hepatic vein anastomotic gradient. In this study group, sinusoidal dilatation and congestion is a nonspecific histopathologic finding that is not a reliable criterion to select patients for venous anastomosis stenting.

Congestive Hepatopathy: Pathophysiology, Workup, and Imaging Findings with Pathologic Correlation

Liver congestion is increasingly encountered in clinical practice and presents diagnostic pitfalls of which radiologists must be aware. The complex altered hemodynamics associated with liver congestion leads to diffuse parenchymal changes and the development of benign and malignant nodules. Distinguishing commonly encountered benign hypervascular lesions, such as focal nodular hyperplasia (FNH)-like nodules, from hepatocellular carcinoma (HCC) can be challenging due to overlapping imaging features. FNH-like lesions enhance during the hepatic arterial phase and remain isoenhancing relative to the background liver parenchyma but infrequently appear to wash out at delayed phase imaging, similar to what might be seen with HCC. Heterogeneity, presence of an enhancing capsule, washout during the portal venous phase, intermediate signal intensity at T2-weighted imaging, restricted diffusion, and lack of uptake at hepatobiliary phase imaging point toward the diagnosis of HCC, although these features are not sensitive individually. It is important to emphasize that the Liver Imaging Reporting and Data System (LI-RADS) algorithm cannot be applied in congested livers since major LI-RADS features lack specificity in distinguishing HCC from benign hypervascular lesions in this population. Also, the morphologic changes and increased liver stiffness caused by congestion make the imaging diagnosis of cirrhosis difficult. The authors discuss the complex liver macro- and microhemodynamics underlying liver congestion; propose a more inclusive approach to and conceptualization of liver congestion; describe the pathophysiology of liver congestion, hepatocellular injury, and the development of benign and malignant nodules; review the imaging findings and mimics of liver congestion and hypervascular lesions; and present a diagnostic algorithm for approaching hypervascular liver lesions. ©RSNA, 2024 Test Your Knowledge questions for this article are available in the supplemental material.

A neuroprotective dose of trehalose is harmless to metabolic organs: comprehensive histopathological analysis of liver, pancreas, and kidney

BACKGROUND

Trehalose is a non-reducing disaccharide synthesized by lower organisms. It has recently received special attention because of its neuroprotective properties by stimulating autophagy in Parkinson's disease (PD) models. Therefore, evaluating whether trehalose affects metabolic organs is vital to determine its neurotherapeutic safety.

METHODS

We validated the trehalose neuroprotective dosage in a PD model induced with intraperitoneal paraquat administration twice weekly for 7 weeks. One week before paraquat administration, mice were treated with trehalose in the drinking water and continued along with paraquat treatment. Histological and morphometrical analyses were conducted on the organs involved in trehalose metabolism, including the liver, pancreas, and kidney.

RESULTS

Paraquat-induced dopaminergic neuronal loss was significantly decreased by trehalose. After trehalose treatment, the liver morphology, the mononucleated/binucleated hepatocytes percentage, and sinusoidal diameter remained unchanged in each liver lobes. Endocrine and exocrine pancreas's histology was not affected, nor was any fibrotic process observed. The islet of Langerhans's structure was preserved when analyzing the area, the largest and smallest diameter, and circularity. Renal morphology remained undamaged, and no changes were identified within the glomerular basement membrane. The renal corpuscle structure did not suffer alterations in the Bowman's space, area, diameter, circularity, perimeter, and cellularity. Besides, the renal tubular structures's luminal area and internal and external diameter were preserved.

CONCLUSION

Our study demonstrates that systemic trehalose administration preserved the typical histological architecture of the organs involved in its metabolism, supporting its safety as a potential neuroprotective agent.

Chemotherapy-Induced Liver Injury in Patients with Colorectal Liver Metastases: Findings from MR Imaging

Chemotherapy-induced liver injury has been found to be quite common in cancer patients undergoing chemotherapy. Being aware of chemotherapy-induced hepatotoxicity is important for avoiding errors in detecting liver metastases and for defining the most appropriate clinical management strategy. MRI imaging has proven to be a useful troubleshooting tool that helps overcome false negatives in tumor response imaging after chemotherapy due to liver parenchyma changes. The purpose of this review is, therefore, to describe the characteristics of magnetic resonance imaging of the broad spectrum of liver damage induced by systemic chemotherapeutic agents in order to avoid misdiagnoses of liver metastases and disease progression and to define the most appropriate clinical management strategy.

Imaging of the chemotherapy-induced hepatic damage: Yellow liver, blue liver, and pseudocirrhosis

The liver is the major drug-metabolizing and drug-detoxifying organ. Many drugs can cause liver damage through various mechanisms; however, the liver response to injury includes a relatively narrow spectrum of alterations that, regardless of the cause, are represented by phlogosis, oxidative stress and necrosis. The combination of these alterations mainly results in three radiological findings: vascular alterations, structural changes and metabolic function reduction. Chemotherapy has changed in recent decades in terms of the drugs, protocols and duration, allowing patients a longer life expectancy. As a consequence, we are currently observing an increase in chemotherapy-associated liver injury patterns once considered unusual. Recognizing this form of damage in an early stage is crucial for reconsidering the therapy regimen and thus avoiding severe complications. In this frontier article, we analyze the role of imaging in detecting some of these pathological patterns, such as pseudocirrhosis, "yellow liver" due to chemotherapy-associated steatosis-steatohepatitis, and "blue liver", including sinusoidal obstruction syndrome, veno-occlusive disease and peliosis.

MR imaging features and long-term evolution of benign focal liver lesions in Budd-Chiari syndrome and Fontan-associated liver disease

PURPOSE

To compare the magnetic resonance imaging (MRI) features of benign liver lesions developed on Budd-Chiari syndrome (BCS) with those on Fontan-associated liver disease (FALD) and to describe their long-term progression.

MATERIALS AND METHODS

Patients with BCS or FALD who underwent MRI between 2010 and 2020 were retrospectively included. MRI features of nodules (≥ 5 mm) at baseline and at final follow-up were reviewed. The final diagnosis of benign lesion was based on a combination of clinical and biological data and findings at follow-up MRI examination.

RESULTS

Two-hundred and thirty benign liver lesions in 39 patients with BCS (10 men, 29 women; mean age, 36 ± 11 [SD] years; age range: 15-66 years) and 84 benign lesions in 14 patients with FALD (2 men, 12 women; mean age, 31 ± 10 [SD] years; age range: 20-48 years) were evaluated. On baseline MRI, BCS nodules were more frequently hyperintense on T1-weighted (183/230, 80%) and hypointense on T2-weighted (142/230; 62%) images, while FALD nodules were usually isointense on both T1- (70/84; 83%) and T2-weighted (64/84; 76%) images (all P< 0.01). Most lesions showed arterial phase hyperenhancement (222/230 [97%] vs. 80/84 [95%] in BCS and FALD, respectively; P = 0.28) but wash-out was more common in BCS (64/230 [28%] vs. 9/84 [11%]; P < 0.01). At follow-up, changes were more frequent in BCS nodules with more frequent disappearance (P < 0.01), changes in size, signal intensity on T2-weighted, portal, and delayed phase, and in the depiction of washout and capsule (all P ≤ 0.03).

CONCLUSION

MRI features of benign lesions are different at diagnosis and during the course of the disease between BCS and FALD. Changes in size and MRI features are more frequent in benign lesions developed in BCS.

Surveillance of Fontan-associated liver disease: current standards and a proposal from the European Society of Paediatric Radiology Abdominal Task Force

Since Francis Fontan first introduced the eponymous technique, the Fontan procedure, this type of surgical palliation has allowed thousands of children affected by specific heart malformations to reach adulthood. Nevertheless, abdominal, thoracic, lymphatic and neurologic complications are the price that is paid by these patients. Our review focuses on Fontan-associated liver disease; the purpose is to summarize the current understanding of its physiopathology, the aim of follow-up and the specific radiologic follow-up performed in Europe. Finally, we as members of the Abdominal Task Force of the European Society of Paediatric Radiology propose a consensus-based imaging follow-up algorithm.

[Drug-induced liver injury-significance of pathology]

Many different medical agents, herbal products, and dietary supplements can induce drug-induced liver injury (DILI) as a clinically relevant complication. DILI, which is direct toxic or idiosyncratic, can have a broad spectrum of clinical appearances from elevation of liver enzymes to acute liver failure. DILI is categorized clinically according to the pattern of serum parameters or pathologically according to the pattern of histomorphology. Histopathological patterns can be described as hepatitic, granulomatous, cholestatic, ductopenic, fibrotic, steatotic, steatohepatitic, and vascular. Correlation to the corresponding drug can be carried out with the corresponding databases (US National Library of Medicine, Liver Tox; www.ncbi.nlm.nih.gov/books/NBK547852/ ). Liver biopsy, in contrast to a clinical/serological diagnostic, has the advantage of an exact resolution with evidence of pathophysiology, activity, regeneration, chronification, and prognosis. Co-occurrence of underlying liver disease can be excluded or confirmed. Histological patterns of DILI are described and illustrated. A diagnostic algorithm for the interpretation of liver biopsies is provided.

Betaine alleviated hepatic and renal injury in diabetic pregnant rats: biochemical and histopathological evidences

Purpose

Pregnancy is the most intense physiological alteration in energy metabolism that women experience in their lifetime. Liver and kidney are the two most susceptible organs to energy metabolism. Diabetes is well-defined as a syndrome interfering with energy metabolism triggered by impaired blood glucose adjustment. Herein, protective effects of betaine on liver and kidney were evaluated in animal model of diabetic pregnancy.

Methods

32 dams were assigned into 4 equal groups: Control (C), Betaine (B, 1.5% w/w of total diet daily), Diabetic pregnancy (D), and Diabetic pregnancy treated with betaine (D + B). After physiological delivery, HbA1c concentration in whole blood, serum hepatic and renal biomarkers such as AST, ALT, ALP, urea and creatinine were measured. Also, liver and kidney tissue samples were examined under a light microscope.

Results

Diabetic pregnancy was found to be accompanied by increased HbA1c level, concentration of hepatic and renal biomarkers in blood samples, and a gamut of alterations such as apoptotic cells, biliary hyperplasia, sinusoidal dilation, basement membrane thickening, and Bowman's capsule dilation as observed in histopathological sections of the D group. Betaine supplementation significantly decreased AST, ALT, urea and creatinine in the D + B group compared to D group. Also, most of pathologic microscopic alterations were attenuated under betaine treatment in D + B group compared to D group.

Conclusion

Findings of the current paper, for the first time, provided evidence regarding protective effects of betaine on liver and kidney function against maternal diabetes in an animal model of STZ-induced diabetic pregnancy.

CT and MR imaging of chemotherapy-induced hepatopathy

Chemotherapy-induced hepatopathy includes a wide variety of parenchymal and vascular hepatic changes on imaging, including diffuse or focal hepatopathies (i.e. hepatitis, steatosis, fibrosis, pseudocirrhosis, or sinusoidal obstruction). These changes can profoundly alter the hepatic parenchyma on imaging and result in both false negative and false-positive diagnoses of hepatic metastases and lead to errors in patient management strategies. It is therefore important for radiologists to have a comprehensive knowledge of the imaging patterns that may develop following chemotherapy. The purpose of this review is to explore the broad spectrum of hepatic parenchymal and vascular chemotherapy-induced changes on CT and MR imaging.

Hepatic sinusoidal dilatation

Hepatic sinusoidal dilatation refers to the enlargement of the hepatic capillaries. Most of the time this condition is caused by hepatic venous outflow obstruction, which results in vascular stasis and congestion of hepatic parenchyma. In this setting, hepatic sinusoidal dilatation can be related to pericardial disease, heart failure, compression or thrombosis of the hepatic veins or inferior vena cava (i.e., Budd-Chiari syndrome) or central veins/sinusoids involvement (i.e., sinusoidal obstruction syndrome). Nevertheless, some extrahepatic inflammatory conditions (such as pyelonephritis, cholecystitis, pneumonia, pancreatitis, intestinal bowel disease, and others) may be associated with hepatic sinusoidal dilatation without concurrent venous outflow obstruction. On contrast-enhanced cross-sectional imaging, hepatic sinusoidal dilatation is typically characterized by a mottled, reticular enhancement of the liver, usually referred to as "mosaic" pattern. Other hepatic and extrahepatic imaging features, such us the dilatation of the hepatic veins or the presence of ascites, can help in identifying the cause of sinusoidal dilatation.

Uncommon evolutions and complications of common benign liver lesions

Frequently encountered on abdominal imaging studies, the majority of common benign liver lesions are asymptomatic, confidently diagnosed by imaging, and do not require further workup, follow-up, or treatment. The increasing use of multimodality liver imaging, has allowed the recognition of uncommon evolutions of common benign liver lesions such as size changes, fibrotic regression, and content and vascularization changes, and their complications such as rupture, hemorrhage, thrombosis, extrinsic compression, and malignancy. The purpose of this pictorial review is to describe and illustrate the incidence and diagnostic features of these uncommon evolutions and complications on cross-sectional imaging, mainly on computed tomography and magnetic resonance imaging, with emphasis on those imaging clues which are helpful in the differential diagnosis or indicate the need for treatment.