Pediatric Hepatic Cystic Lesions: Differential Diagnosis and Multimodality Imaging Approach

Massive Hepatomegaly in a Pediatric Patient Due to a Solitary Simple Hepatic Cyst: A Case Report

This case report presents a six-year-old male patient with massive hepatomegaly attributed to a solitary simple hepatic cyst. The patient was referred to the pediatric gastroenterology clinic after his family noted progressive abdominal distention over four months, with no associated symptoms such as pain, jaundice, or systemic illness. Physical examination revealed significant hepatomegaly and initial laboratory investigations indicated mild transaminitis but were otherwise unremarkable. Imaging with abdominal ultrasound demonstrated a single large cystic lesion, which was further characterized by computed tomography (CT) as a 12-cm simple hepatic cyst. The differential diagnosis included conditions such as polycystic liver disease and hydatid disease, but these were ruled out based on clinical presentation and imaging findings. Given the benign nature of the cyst and the absence of symptoms, conservative management was pursued, with regular follow-up to monitor for potential complications. The patient remained asymptomatic during a six-month follow-up, highlighting the importance of individualized monitoring and management in cases of pediatric hepatic cysts. This case contributes to the understanding of simple hepatic cysts in children and underscores the need for careful diagnostic evaluation and long-term follow-up.

Biliary Disorders, Anomalies, and Malignancies in Children

Biliary abnormalities in children are uncommon, and the spectrum of biliary disorders is broader than in adult patients. Unlike in adults, biliary disorders in children are rarely neoplastic and are more commonly rhabdomyosarcoma rather than cholangiocarcinoma. Pediatric biliary disorders may be embryologic or congenital, such as anatomic gallbladder anomalies, anomalous pancreaticobiliary tracts, various cholestatic processes, congenital cystic lesions, or genetic conditions. They may also be benign, such as biliary filling anomalies, biliary motility disorders, and biliary inflammatory and infectious disorders. Distinguishing these entities with a single imaging modality is challenging. US is the primary imaging modality for initial evaluation of biliary abnormalities in children, due to its wide availability, lack of ionizing radiation, and low cost and because it requires no sedation. Other examinations such as MRI, CT, and nuclear medicine examinations may provide anatomic and functional information to narrow the diagnosis further. Hepatobiliary-specific contrast material with MRI can provide better assessment of biliary anatomy on delayed images than can traditional MRI contrast material. MR cholangiopancreatography (MRCP) allows visualization of the intra- and extrahepatic biliary ducts, which may not be possible with endoscopic retrograde cholangiopancreatography (ERCP). Suspected biliary atresia requires multiple modalities for diagnosis and timely treatment. Determining the type of choledochal cyst calls for a combination of initial US and MRCP. Many benign and malignant biliary masses require biopsy for definitive diagnosis. Knowledge of the imaging appearances of different pediatric biliary abnormalities is necessary for appropriate imaging workup, providing a diagnosis or differential diagnosis, and guiding appropriate management. ©RSNA, 2024 Test Your Knowledge questions for this article are available in the supplemental material.

Cancer Therapy-related Hepatic Injury in Children: Imaging Review from the Pediatric LI-RADS Working Group

The liver is the primary organ for the metabolism of many chemotherapeutic agents. Treatment-induced liver injury is common in children undergoing cancer therapy. Hepatic injury occurs due to various mechanisms, including biochemical cytotoxicity, hepatic vascular injury, radiation-induced cytotoxicity, and direct hepatic injury through minimally invasive and invasive surgical treatments. Treatment-induced liver injury can be seen contemporaneous with therapy and months to years after therapy is complete. Patients can develop a combination of hepatic injuries manifesting during and after treatment. Acute toxic effects of cancer therapy in children include hepatitis, steatosis, steatohepatitis, cholestasis, hemosiderosis, and vascular injury. Longer-term effects of cancer therapy include hepatic fibrosis, chronic liver failure, and development of focal liver lesions. Quantitative imaging techniques can provide useful metrics for disease diagnosis and monitoring, especially in treatment-related diffuse liver injury such as hepatic steatosis and steatohepatitis, hepatic iron deposition, and hepatic fibrosis. Focal liver lesions, including those developing as a result of treatment-related vascular injury such as focal nodular hyperplasia-like lesions and hepatic perfusion anomalies, as well as hepatic infections occurring as a consequence of immune suppression, can be anxiety provoking and confused with recurrent malignancy or hepatic metastases, although there often are imaging features that help elucidate the correct diagnosis. Radiologic evaluation, in conjunction with clinical and biochemical screening, is integral to diagnosing and monitoring hepatic complications of cancer therapy in pediatric patients during therapy and after therapy completion for long-term surveillance. ©RSNA, 2023 Quiz questions for this article are available in the supplemental material See the invited commentary by Ferraciolli and Gee in this issue.

Neonatal pyogenic liver abscess following omphalitis: A case report

INTRODUCTION AND IMPORTANCE

Liver abscesses in neonates are rare. Omphalitis is a very rare cause. We report a case of a voluminous neonatal pyogenic liver abscess following omphalitis, successfully managed in our institution.

CASE PRESENTATION

A 21-day-old full-term female newborn was brought to our institution for progressive febrile swelling of the right hypochondrium. The parents reported umbilical suppuration. Clinical examination confirmed the presence of a mass extending from the epigastric region to the right hypochondrium in a febrile baby with no other abnormalities. Laboratory investigations revealed an elevated C-reactive protein level (64 mg/dl) and hyperleukocytosis (20,800/mm3) with neutrophil predominance and normochromic microcytic anemia (hemoglobin 8.2 g/dl). Her first abdominal ultrasound was interpreted as a cyst of the common bile duct. Triple antibiotic therapy with cephalosporin, ampicillin and gentamycin was started, but unsuccessful. Abdominal ultrasound was repeated, revealing a hepatic abscess in segment 8, with a volume of approximately 17 ml. Percutaneous echo-guided drainage was performed and antibiotic therapy was readjusted after identification of the germ (Staphylococcus aureus) with good outcome. The baby was discharged two weeks later. At one month follow-up, the baby was completely asymptomatic.

CLINICAL DISCUSSION AND CONCLUSION

As neonatal liver abscesses are unusual, they can lead to misdiagnosis. Omphalitis is a very rare cause. Treatment by percutaneous echo-guided drainage is simple and effective.