Rezan Topaloglu

Rezan Topaloğlu is a Turkish pediatrician and an academic. She is a Professor of Pediatrics at Hacettepe University and Acıbadem Healthcare Group.^[1]

Topaloğlu is known for her work on pediatric nephrology and clinical genetics. Her work has been published in academic journals such as Kidney International, Clinical Journal of the American Society of Nephrology, Journal of Pediatric Nephrology, Nephrology Dialysis and Transplantation, Nature, the European Journal of Human Genetics and Journal of Medical Genetics.^[2] Moreover, she is the chair of IPNA (International Pediatric Nephrology Association) Junior Master Classes^[3] and recipient of the 2022 IPNA Educational Activity Award for her work leading Pediatric Nephrology formal Education Classes.^[4]

Topaloğlu earned her Doctor of Medicine degree from Hacettepe University Faculty of Medicine in Ankara, Turkey, and undertook an elective study at Leeds General Infirmary, University of Leeds, United Kingdom. She began her academic career at Hacettepe University Children's Hospital as an instructor in pediatrics from 1988 to 1991. From 1991 to 1999, she served as an associate professor of pediatrics, specializing in pediatric nephrology and rheumatology. During her fellowship in pediatric nephrology and rheumatology, she worked at Guy’s and Hammersmith Hospital in London, focusing on C1q deficiency and nephrotic syndrome. She also worked as a research fellow at the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) at the National Institutes of Health (NIH) in the United States, where she studied Bartter syndrome. She was promoted to professor of pediatrics in 1999 and held this position at Hacettepe University until 2023. Since 2023, she has been affiliated with Acıbadem Healthcare Group as a consultant and professor of pediatrics, with continued specialization in pediatric nephrology and rheumatology.^[1]

Topaloğlu also holds administrative and professional experience. She held appointments as a council member of both the European Society for Pediatric Nephrology and the International Pediatric Nephrology Association from 2013 to 2019, and subsequently, she was appointed to Executive Board Member of the International Pediatric Nephrology Association from 2019 to 2022, as well as President of the European Society for Pediatric Nephrology during the same period.^[1]

Topaloğlu, in her early research, authored a paper wherein she reported a rare hereditary C1q deficiency in two Turkish siblings, linked to SLE and IgA nephropathy. It identified a specific mutation and confirmed it was not common in broader SLE populations.^[5] In a nationwide multicenter study, she analyzed 2,838 Turkish FMF patients, detailing diagnoses, common symptoms, genetic mutations (mainly M694V), and devistating complications like amyloidosis, highlighting genotype-phenotype links and misdiagnoses, especially in children.^[6] Her collaborative research also identified the MEFV gene within a 60 kb region, discovered disease-linked mutations in the marenostrin protein-pyrin protein, and proposed these mutations as the genetic cause of Familial Mediterranean Fever.^[7]

Topaloğlu’s work also explored genetic mutations causing autosomal recessive distal renal tubular acidosis, linked them to hearing loss, identified novel ATP6V1B1 and ATP6V0A4 mutations, suggested further genetic heterogeneity, and showed ATP6V0A4 expression in the cochlea.^[8] Her collaborative work also showed that combining mesangial and endocapillary hypercellularity, segmental sclerosis, and interstitial fibrosis/tubular atrophy (MEST) scores with clinical data at biopsy predicted IgA nephropathy progression as accurately as 2-year follow-up data, enabling earlier risk stratification and improved clinical decision-making.^[9] Furthermore, she also reviewed cystinosis, a rare genetic disorder causing renal Fanconi syndrome in children, and summarized expert opinions to improve diagnosis, raise awareness, and guide effective treatment and early treatment in infancy to enhance patient outcomes.^[10]

In her investigation of clinical features and CTNS gene mutations in Turkish children with cystinosis, Topaloğlu’s team identified novel variants and common mutations and linked early treatment and mutation type to kidney disease progression and outcomes.^[11] Additionally, she reviewed cystinosis, focusing on geographic differences in CTNS gene mutations, clinical features, treatment limitations of cysteamine, and long-term complications, and highlighted the need for novel therapeutic approaches.^[12] In her research, she reported that male sex, failure to achieve remission at 6 and 12 months, and the requirement for dialysis at the time of diagnosis were significant predictors of poor renal outcomes, and concluded that appropriate and aggressive management of pediatric lupus nephritis is essential to achieve and maintain remission.^[13] Moreover, she presented expert-backed clinical guidelines for diagnosing and managing COL4A3/4/5-related kidney diseases like Alport syndrome, emphasizing genetic testing, early treatment, and cautious living donation, based on systematic evidence and global consensus.^[14]

• Yilmaz, E., Ozen, S., Balcı, B., Duzova, A., Topaloğlu, R., Besbas, N., ... & Ozguc, M. (2001). Mutation frequency of familial Mediterranean fever and evidence for a high carrier rate in the Turkish population. European journal of human genetics, 9(7), 553-555.
• Stover, E. H., Borthwick, K. J., Bavalia, C., Eady, N., Fritz, D. M., Rungroj, N., ... & Karet, F. E. (2002). Novel ATP6V1B1 and ATP6V0A4 mutations in autosomal recessive distal renal tubular acidosis with new evidence for hearing loss. Journal of Medical Genetics, 39(11), 796-803.
• Turkish FMF Study Group. (2005). Familial Mediterranean fever (FMF) in Turkey: results of a nationwide multicenter study. Medicine, 84(1), 1-11.
• Heeringa, S. F., Chernin, G., Chaki, M., Zhou, W., Sloan, A. J., Ji, Z., ... & Hildebrandt, F. (2011). COQ6 mutations in human patients produce nephrotic syndrome with sensorineural deafness. The Journal of Clinical Investigation, 121(5), 2013-2024.
• Braun, D. A., Rao, J., Mollet, G., Schapiro, D., Daugeron, M. C., Tan, W., ... & Hildebrandt, F. (2017). Mutations in KEOPS-complex genes cause nephrotic syndrome with primary microcephaly. Nature Genetics, 49(10), 1529-1538.
• Nemutlu, E., Ozaltin, F., Yabanoglu-Ciftci, S., Gulhan, B., Eylem, C. C., Baysal, İ., ... & Topaloğlu, R. (2023). Metabolomic analyses to identify candidate biomarkers of cystinosis. International Journal of Molecular Sciences, 24(3), 2603.
• Baysal, İ., Yabanoglu-Ciftci, S., Nemutlu, E., Eylem, C. C., Gök-Topak, E. D., Ulubayram, K., ... & Topaloğlu, R. (2024). Omic Studies on In Vitro Cystinosis Model: siRNA-Mediated CTNS Gene Silencing in HK-2 Cells. Laboratory Investigation, 104(1), 100287.