Focal inflammatory diseases of the liver

Percutaneous treatment of liver hydatid cysts: to PAIR or not to PAIR

PURPOSE OF REVIEW

The aim is to review recent literature for percutaneous treatment of liver hydatid cysts (cystic echinococcosis: CE) via different techniques such as PAIR (puncture, aspiration, injection, and reaspiration), standard catheterization, and modified catheterization technique (MoCaT).

RECENT FINDINGS

PAIR is an established technique and considered to be safe and effective for CE1 and CE3a as it is associated with lower morbidity, mortality, recurrence, and shorter hospital stay as compared with surgery. Standard catheterization is also dedicated for the treatment of CE1 and CE3a. PAIR should be preferred for treatment of liver CE1 and CE3a cysts, since PAIR is associated with lower major complication rates and shorter hospital stay. However, standard catheterization technique is indicated when cysto-biliary fistula develops or any technical difficulty arises during the PAIR. In these cases it is needed to switch PAIR to standard catheterization to complete the procedure.

SUMMARY

For CE1 and CE3a cysts, PAIR and standard catheterization are the choice for percutaneous treatments, while MoCaT is a treatment option for CE2 and CE3b cysts.

Benign liver lesions 2022: Guideline for clinical practice of Associazione Italiana Studio del Fegato (AISF), Società Italiana di Radiologia Medica e Interventistica (SIRM), Società Italiana di Chirurgia (SIC), Società Italiana di Ultrasonologia in Medicina e Biologia (SIUMB), Associazione Italiana di Chirurgia Epatobilio-Pancreatica (AICEP), Società Italiana Trapianti d'Organo (SITO), Società Italiana di Anatomia Patologica e Citologia Diagnostica (SIAPEC-IAP) - Part I - Cystic lesions

Benign liver lesions are increasingly diagnosed in daily clinical practice due to the growing use of imaging techniques for the study of the abdomen in patients who have non-specific symptoms and do not have an increased risk of hepatic malignancy. They include simple or parasitic cysts and solid benign tumors which differ widely in terms of prevalence, clinical relevance, symptoms and natural history and often lead to significant clinical problems relating to diagnosis and clinical management. Following the need to have updated guidelines on the management of benign focal liver lesions, the Scientific Societies mainly involved in their management have promoted the drafting of a new dedicated document. This document was drawn up according to the present Italian rules and methodologies necessary to produce clinical, diagnostic, and therapeutic guidelines based on evidence. Here we present the first part of the guideline, concerning the characterization of focal hepatic lesions detected by ultrasound, and the diagnosis and clinical management of simple and parasitic hepatic cysts, and of polycystic liver disease.

Typical imaging finding of hepatic infections: a pictorial essay

Hepatic infections are frequent in clinical practice. Although epidemiological, clinical and laboratory data may suggest hepatic infection in certain cases, imaging is nearly always necessary to confirm the diagnosis, assess disease extension and its complications, evaluate the response to treatment, and sometimes to make differential diagnoses such as malignancies. Ultrasound (US) is usually the first-line investigation, while computed tomography (CT) and magnetic resonance imaging (MRI) provide better characterization and a more precise assessment of local extension, especially biliary and vascular. The purpose of this article is to describe the typical features and main complications of common hepatic infections. Familiarity with the radiological features of this entity can help suggest the correct diagnosis and the need for further studies as well as determine appropriate and timely treatment.

Beyond pyogenic liver abscess: a comprehensive review of liver infections in emergency settings

Hepatobiliary infections are commonly encountered in emergency settings ranging from common pathology such as pyogenic abscess to relatively uncommon and rare etiologies. Since extensive literature is already available on imaging of more common bacterial infections, for the sake of focused discussion, this review will discuss radiological appearance of less commonly encountered hepatic infections of fungal, parasitic, viral, and tubercular etiologies. Epidemiological and clinical information remain extremely important for obtaining more accurate presumptive diagnosis. In the era of diverse population migration, a modern-era radiologist must be well versed about the imaging spectrum of liver infections.

The Echinococcoses: Diagnosis, Clinical Management and Burden of Disease

The echinococcoses are chronic, parasitic diseases that are acquired after ingestion of infective taeniid tapeworm eggs from certain species of the genus Echinococcus. Cystic echinococcosis (CE) occurs worldwide, whereas, alveolar echinococcosis (AE) is restricted to the northern hemisphere, and neotropical echinococcosis (NE) has only been identified in Central and South America. Clinical manifestations and disease courses vary profoundly for the different species of Echinococcus. CE presents as small to large cysts, and has commonly been referred to as 'hydatid disease', or 'hydatidosis'. A structured stage-specific approach to CE management, based on the World Health Organization (WHO) ultrasound classification of liver cysts, is now recommended. Management options include percutaneous sterilization techniques, surgery, drug treatment, a 'watch-and-wait' approach or combinations thereof. In contrast, clinical manifestations associated with AE resemble those of a 'malignant', silently-progressing liver disease, with local tissue infiltration and metastases. Structured care is important for AE management and includes WHO staging, drug therapy and long-term follow-up for at least a decade. NE presents as polycystic or unicystic disease. Clinical characteristics resemble those of AE, and management needs to be structured accordingly. However, to date, only a few hundreds of cases have been reported in the literature. The echinococcoses are often expensive and complicated to treat, and prospective clinical studies are needed to better inform case management decisions.

The "frosted liver" appearance in hepatic tuberculosis: a rare presentation

Tuberculosis is a major re-emerging global health concern. The disease may involve any body system and is a great mimicker of various pathologies owing to its non-specific imaging findings. Herein we report an extremely rare case of atypical tuberculosis of the liver in a young female with complaints of abdominal pain and haematemesis for 10 weeks. Isolated hepatic tuberculosis is a rare entity with < 100 cases reported in the literature. It is therefore important to have a high index of suspicion and be familiar with the atypical imaging findings of abdominal tuberculosis. This discussion highlights the clinical presentation, imaging findings and types of hepatic involvement in tuberculosis.

Imaging of multifocal hepatic lesions in pediatric patients

Imaging plays a vital role in detection and characterization of multifocal liver lesions in children. Numerous causes for these lesions exist, including benign and malignant neoplasms, infectious lesions, and congenital and inflammatory conditions. The imaging spectrum of multifocal liver lesions in children is presented with emphasis on key imaging features, differential diagnoses and helpful relevant clinical features.

Fasciola hepatica infection in a 65-year-old woman

Fascioliasis is an infectious disease caused by fasciola or liver fluke. Humans are accidental hosts to these flatworms. The World Health Organisation considers fascioliasis an important human parasitic disease. In Europe, Australia and Northern America, the disease is rare, but should have a high index of suspicion in patients who have lived in or travelled to endemic areas. Although it can be self-limiting, fascioliasis is associated with an increased risk of bile duct cancer. Before a clear-cut diagnosis is made using ELISA-based arrays, radiologic studies can provide the clinician with a number of suggestive features, thereby avoiding the need for liver biopsy or even surgery, which have nowadays become obsolete for the diagnosis of fascioliasis. We provide an overview of the major radiologic hallmarks and we demonstrate the role of iron-oxide enhanced MRI.

Echinococcosis of the liver

Echinococcosis, also known as hydatid disease, is an infection of larval stage animal tapeworm, Echinococcus. The larvae reside in the liver and lungs, producing multiloculated fluid-filled cysts. Imaging findings of Echinococcosis caused by E. granulosus are single, unilocular cyst or multiseptated cysts, showing "wheel-like", "rosette-like" or "honeycomb-like" appearances. There may be "snow-flakes" sign, reflecting free floating protoscoleces (hydatid-sand) within the cyst cavity. Degenerating cysts show wavy or serpentine bands or floating membranes representing detached or ruptured membranes. Degenerated cysts show heterogeneous, solid-looking pseudotumor that may show "ball of wool sign". Dead cysts show calcified cyst wall. Echinococcosis caused by E. multilocularis produces multilocular alveolar cysts with exogeneous proliferation, progressively invading the liver parenchyma and other tissues of the body. Imaging findings are ill-defined infiltrating lesions of the liver parenchyma, consisting of multiple small clustered cystic and solid components. On sonography, lesions are heterogeneous with indistinct margins, showing "hailstorm appearance" or "vesicular or alveolar appearance". CT and MR imaging displays multiple, irregular, ill-defined lesions. Multiple small round cysts with solid components are frequent. Large lesions show "geographical map" appearance. Calcifications are very frequent, appearing as peripheral calcification or punctuate scattered calcific foci. Invasion into the bile ducts, portal vein or hepatic vein may occur. Direct spread of infected tissue may result in cysts in the peritoneal cavity, kidneys, adrenal gland or bones.

Abdominal MRI advances in the detection of liver tumours and characterisation

With recent technical advances in hardware, software, and intravenous contrast agents, MRI has evolved into a clinically useful procedure to detect and characterise liver tumours. The combination of MRI systems with larger gradients, improved surface coils, and parallel imaging techniques have produced substantial improvements in MRI quality and speed of image acquisition. Images that previously needed several minutes to acquire can now be obtained in several seconds. The notably faster imaging capabilities of new MRI scanners are ideally suited for dynamic contrast-enhanced liver imaging in which early arterial-phase imaging is best for detecting hepatocellular carcinomas and hypervascular liver metastases. The inherent excellent soft-tissue contrast of MRI can be further improved by non-specific extracellular contrast agents and by liver-specific contrast agents. These contrast agents are now routinely used for liver imaging and improve the sensitivity and specificity of hepatobiliary MRI.

Imaging of hepatic infections

Imaging plays a significant role in the detection, characterization and treatment of hepatic infections. Infectious diseases of the liver include pyogenic and amoebic abscesses and parasitic, fungal, viral and granulomatous infections. With increases in worldwide travel, immunosuppression and changing population demographics, identification of cases of hepatic infection is becoming more common in daily practice. Knowledge of the imaging features seen with hepatic infections can assist in early diagnosis and timely initiation of appropriate therapy. This review presents the imaging appearances of hepatic infections, emphasizing specific features that may contribute to the diagnosis. Examples of the imaging findings seen with pyogenic and amoebic abscesses, infection with Echinococcus granulosus (Hydatid), schistosomiasis, candidiasis and tuberculosis (TB) are presented.

CT appearance of Varicella Zoster lesions in liver and spleen in an immunocompetent patient

An adult patient presented with vesicular rash and abdominal pain of 5 days duration. His initial laboratory results showed elevated liver enzymes. A contrast enhanced CT scan demonstrated multiple small hypodense nodules in liver and spleen. His serum was reactive for Varicella Zoster IgM. Patient was treated with intravenous Acyclovir for 5 days and followed up with oral tablets for 2 weeks. At 3 weeks, CT scan showed resolution of hypodense nodules and his serum liver enzymes returned to normal at 6 weeks. Patient is on follow up and asymptomatic for 2 years. The CT appearances of nodules and their resolution following specific antiviral therapy are useful in diagnosis and in follow up of disseminated Varicella Zoster.

Imaging diagnosis of 12 patients with hepatic tuberculosis

AIM

To assess CT, MR manifestations and their diagnostic value in hepatic tuberculosis.

METHODS

CT findings in 12 cases and MR findings in 4 cases of hepatic tuberculosis proved by surgery or biopsy were retrospectively analyzed.

RESULTS

(1) CT findings: One case of serohepatic type of hepatic tuberculosis had multiple-nodular lesions in the subcapsule of liver. Parenchymal type was found in 10 cases, including multiple, miliary, micronodular and low-density lesions with miliary calcifications in 2 cases; singular, low-density mass with multiple flecked calcifications in 3 cases; multiple cystic lesions in 1 case; multiple micronodular and low-density lesions fusing into multiloculated cystic mass or "cluster" sign in 3 cases; and singular, macronodular and low-density lesion with multiple miliary calcifications in 1 case. One case of tuberculous cholangitis showed marked dilated intrahepatic ducts with multiple flecked calcifications in the porta hepatis. (2) MR findings in 4 cases were hypointense on both T1-weighted imagings and T2-weighted imagings in one case, hypointense on T1-weighted imagings and hyperintense on T2-weighted imagings in 3 cases. Enhanced MR in 3 cases was slightly shown peripheral enhancement or with multilocular enhancement.

CONCLUSION

Various types of hepatic tuberculosis have different imaging findings, and typical CT and MR findings can suggest the diagnosis.

MR imaging of infective liver lesions

This article discusses MR imaging of infective liver lesions including pyogenic liver abscesses, amebic liver abscesses, echinococcal disease, hepatic fungal abscesses, granulomatous hepatic infections, schistosomiasis, and fascioliasis.