Pediatr Nephrol (2005) 20:945–949 DOI 10.1007/s00467-004-1800-x ORIGINAL ARTICLE Maria M. Rodriguez · Alexander Gomez · Carolyn Abitbol · Jayanthi Chandar · Brenda MontanØ · Gastón Zilleruelo Comparative renal histomorphometry: a case study of oligonephropathy of prematurity Received: 12 December 2003 / Revised: 19 November 2004 / Accepted: 22 November 2004 / Published online: 26 April 2005  IPNA 2005 Abstract Children born with very low birth weight have a decreased nephron number. Low nephron mass is as- sociated with adult hypertension, proteinuria, and diabetes mellitus. The histomorphometry and radial glomerular count (RGC) of a total nephrectomy from a child with renal disease associated with extreme prematurity was compared with the kidney from a full-term age-matched child of normal gestation with chronic renal failure due to focal and segmental glomerulosclerosis (FSGS) and to a child without renal disease. Bowman’s space area, me- sangium and mesangial tuft area were determined in 50 glomeruli of each specimen by computer-assisted mor- phometry. RGC was 4 in the ex-preterm child, 8 in the patient with FSGS, and 9 in normal control. The patient with FSGS had larger glomerular area expressed as square micrometers (mm 2 ) of Bowman’s capsule, the mesangium and the mesangial tuft area measurements than the normal control and the child born preterm who subsequently developed renal failure had significantly larger Bowman’s capsule and mesangium than the two controls. This case report begins to identify important pathologic findings of decreased nephron numbers and glomerulomegaly asso- ciated with preterm birth. Keywords Hypertension · Low birth weight · Neonatal renal failure · Nephrogenesis · Oligonephronia · Oligonephropathy Introduction There is a growing interest in the fetal origins of adult disease, particularly regarding the associations of low birth weight with low nephron numbers and subsequent risks for adult cardiovascular disease [1,2]. Experimental studies have shown that maternal protein deprivation re- sults in offspring with fewer nephrons and adult hyper- tension [1]. Similarly, autopsy series demonstrate a de- crease in nephron numbers in human infants with low birth weight born small for gestational age [3,4]. In select populations, including those of African descent, low nephron mass is associated with adult hypertension, pro- teinuria, and diabetes [1]. Until recently, no study has addressed the potential impact of prematurity alone as a cause of interrupted nephrogenesis and subsequent renal failure linked to the fact that nephron formation is be- lieved to continue up until 36 weeks’ gestation in the human and primate [5]. In the present case study, we have identified a patient born preterm but appropriate for gestational age (AGA) who developed progressive renal disease after recovery from vasomotor nephropathy in the newborn period. The purpose of this comparison was to determine whether there was evidence of interrupted nephrogenesis by counting nephron generations in three total nephrectomies (one patient and two controls) and to analyze glomerular size by computer-assisted morphometry. Methods Patients In our recently published long-term follow-up of infants with ex- treme low birth weight (ELBW) and neonatal acute renal failure, M. M. Rodriguez · A. Gomez Division of Pediatric Pathology, University of Miami/Holtz Children’s Hospital, Miami, FL, USA C. Abitbol · J. Chandar · B. MontanØ · G. Zilleruelo Division of Pediatric Nephrology, University of Miami/ Holtz Children’s Hospital, Miami, FL, USA M. M. Rodriguez ( ) ) Department of Pathology/Holtz Children’s Hospital, Holtz Center 2142, 1611 NW 12 Avenue, Miami, FL, 33136, USA e-mail: mrodrig2@med.miami.edu Tel.: +1-305-5856637 Fax: +1-305-5855311