Liesegang Rings in Kidney Diseases- A Systematic Review

Introduction: Liesegang rings (LR) are concentric acellular lamellar structures, usually found in cystic and inflammatory tissues but can also be seen in neoplastic conditions. They have been mistakenly interpreted as various structures like psammomatous calcification, parasites, and algae. This study has aimed to systematically review and summarize the existence of LRs in both non-neoplastic and neoplastic conditions of the kidney. The systematic search in PUBMED, PUBMED CENTRAL, and EMBASE databases along with Google Scholar was performed by using Kidney, Liesegang Rings, or Liesegang structure or pseudo parasitic structure in combination with the Boolean operators ''and" as searching terms. Data were collected for demographic characteristics and histopathology diagnosis. The search function was limited to human subjects. Two reviewers independently performed the eligibility assessment and data extraction. Eligibility inclusion criteria were all publications in the English literature worldwide related to Liesegang rings in association with kidney's non-neoplastic and neoplastic conditions, regardless of the years of publication. Also included were those cases whose full articles were unavailable, but the abstract was well-described, fulfilling our inclusive criteria. Eligibility exclusion criteria included LRs found elsewhere in the body organs apart from the kidney and availability of full text in a different language, non-human, and duplicate article/case. Methods: After the exclusion of the articles as per the exclusion criteria, the total articles that fulfilled the inclusive criteria were reviewed. In addition, all the articles were further cross-referenced for additional articles. All published papers retrieved from this search were considered for this review. A total of 22 records (26 cases) were found with a diagnosis of LRs in the kidney to date. Some articles were published as case series. Accordingly, 26 patients were reported to have Liesegang rings associated with kidney neoplastic and non-neoplastic conditions, 12 were male and 14 were female. For one case the gender was not mentioned. LRs presented a higher frequency in individuals between the 4th and 5th decades of life. No single case was reported in infants and younger children. Regarding predisposing factors for LRs, cystic fluid contents were the most common underlying condition. Results: In our practice, we encountered an unusual case of a 55-year-old female with a complaint of pain in the left upper quadrant of the abdomen. The ultrasound revealed nephrolithiasis and chronic kidney disease for which a nephrectomy was performed. On the histopathological examination, there was an incidental finding of Liesegang rings and a papillary adenoma along with features of chronic pyelonephritis. Our review will provide insight into LRs in different spectrums of kidney diseases. Conclusion: This study represents the first available systematic review of the literature demonstrating LRs in the kidney. Although Liesegang rings have no great clinical significance, nonetheless, their presence in both tissue and cytological specimens should be kept in mind while dealing with different lesions of the kidney as they are good mimickers of many organic and inorganic substances, parasites, and malignancies.