Imaging of Kidney Cysts and Cystic Kidney Diseases in Children: An International Working Group Consensus Statement

Abstract

ystic kidney diseases are being diagnosed earlier and earlier (1) because of more accessible routine prenatal US and advances in US technology. However, differential diagnosis often remains a challenge because kidney cysts can arise in a large variety of illnesses, imaging patterns evolve over time, and extrarenal features of systemic diseases may not be present at a young age. Thus, imaging findings for a particular disease in newborns may be different from those in adolescents, and predicting prognosis or deciding on optimal follow-up intervals can be challenging. Imaging can contribute not only to accurate diagnosis and prognosis but also to rational management of cystic nephropathies. In adults with autosomal dominant polycystic kidney disease (ADPKD), for example, total kidney volume measured at MRI has emerged as a useful tool with which to identify patients who will benefit from treatment (2); however, transfer and adaptation of these findings to children is still an important research need. The purpose of this consensus statement is to establish uniform standards for choosing the correct imaging modality and diagnostic criteria for the most common cystic kidney diseases in childhood and adolescence and to propose rational approaches to diagnosis and follow-up in important clinical settings. The spectrum of diseases covered here includes simple cysts; multicystic dysplastic kidneys (MCDKs); cystic dysplasia and HNF1B-associated disease; autosomal recessive polycystic kidney disease (ARPKD) and ADPKD; other ciliopathies, such as nephronophthisis and Bardet-Biedl syndrome; acquired cystic kidney disease

International consensus statement on the diagnosis and management of autosomal dominant polycystic kidney disease in children and young people

“…In line with clinical practice guidelines for adults [26][27][28] , we recommend reserving genetic testing to selected situations (see below). We have provided detailed guidance on the prenatal and postnatal imaging of single and multiple kidney cysts and their differential diagnosis in separate statements 29,30 .…”

Results of targeted next-generation sequencing in children with cystic kidney diseases often change the clinical diagnosis

“…Clinical diagnosis of ADPKD was based on the presence of one or more kidney cysts in one/both kidneys with or without positive family history of ADPKD and was mostly based on expert opinion as no consensus diagnostic criteria were stated for children under the age of 15. Retrospective evaluation shows that diagnosis of ADPKD in our patients followed the international consensus statement for radiological criteria for children and young people published in 2019 [4,5], where 1) findings of one or more kidney cysts in children under 15 years with a positive family history of ADPKD are highly suggestive of ADPKD and 2) multiple cysts with negative family history require clinical work-up for cystic kidney diseases.…”

Autosomal Recessive Polycystic Kidney Disease—The Clinical Aspects and Diagnostic Challenges

“…However, the classic US appearance of ARPKD shows bilaterally enlarged kidneys with heterogeneous parenchymal echogenicity with a salt-and-pepper pattern (caused by multiple tiny barely detectable cysts, which disrupt the echo pattern without being clearly distinguishable). 19 The salt-and-pepper pattern is mainly visible in children older than 6 years.…”