Congenital capillary proliferation of the kidney: a distinctive renal vascular lesion of childhood

Mariana M. Cajaiba, Paula E. North, Shunyou Gong, Paul S. Dickman, Elizabeth Mroczek-Musulman, David Sauer, Elizabeth J. Perlman

Research output: Contribution to journalArticle

1 Scopus citations


Renal vascular lesions (RVL) are rare, and their morphological spectrum remains largely unknown, particularly in children. In this study, we characterize the clinicopathological features of RVL in a cohort of 12 children. Seven lesions were classified as previously recognized entities: vascular malformations (4), papillary endothelial hyperplasia (2), and pyogenic granuloma (lobular capillary hemangioma; 1). An eighth lesion showed nonspecific findings, which were interpreted as reactive during our review. The remaining 4 cases presented either prenatally, at birth, or shortly after birth and were morphologically similar. These were characterized by a peculiar pattern of capillary proliferation with entrapment of native renal structures, variable amounts of extramedullary hematopoiesis and reactive lymphocytes, foci of infarction and hemorrhage, and the presence of feeding and draining vessels at their periphery. To our knowledge, this represents a previously undescribed congenital vascular lesion involving the kidney, which we have descriptively and provisionally termed congenital capillary proliferation of the kidney (CCPK). While it is unclear whether CCPK represents a malformation or neoplastic proliferation, it shows overlapping features with congenital hemangioma of the liver (solitary congenital hepatic hemangioma) and congenital nonprogressive hemangioma (CNH) of the skin and soft tissue, suggesting a possible common pathogenesis among these 3 entities.

Original languageEnglish (US)
Pages (from-to)59-66
Number of pages8
JournalHuman Pathology
StatePublished - Aug 1 2017



  • Congenital
  • Hemangioma
  • Kidney
  • Malformation
  • Pediatric
  • Vascular lesions

ASJC Scopus subject areas

  • Pathology and Forensic Medicine

Cite this

Cajaiba, M. M., North, P. E., Gong, S., Dickman, P. S., Mroczek-Musulman, E., Sauer, D., & Perlman, E. J. (2017). Congenital capillary proliferation of the kidney: a distinctive renal vascular lesion of childhood. Human Pathology, 66, 59-66.