The Changing Landscape of Neonatal Diabetes Mellitus in Italy Between 2003 and 2022
Novella Rapini, Maurizio Delvecchio, Mafalda Mucciolo, Rosario Ruta, Ivana Rabbone, Valentino Cherubini, Stefano Zucchini, Stefano Cianfarani, Elena Prandi, Riccardo Schiaffini, Carla Bizzarri, Barbara Piccini, Giulio Maltoni, Barbara Predieri, Nicola Minuto, Rossella Di Paola, Mara Giordano, Nadia Tinto, V. Grasso, Lucia Russo, Valentina Tiberi, Andrea Scaramuzza, Giulio Frontino, Maria Cristina Maggio, Gianluca Musolino, Elvira Piccinno, Davide Tinti, Paola Carrera, Enza Mozzillo, Marco Cappa, Dario Iafusco, Riccardo Bonfanti, Antonio Novelli, Fabrizio Barbetti, Diabetes Study Group of Italian Society for Pediatric Endocrinology and Diabetes (ISPED), Luciano Beccaria, Francesco Candia, Vittoria Cauvin, Roberta Cardani, Francesca Cardella, Anna Favia, Francesco Gallo, Patrizia Garzia, Paolo Ghirri, Stefania Innaurato, Lorenzo Iughetti, Nicola Laforgia, Donatella Lo Presti, Alberto Marsciani, Franco Meschi, Rossana Panzeca, B Pasquino, Roberta Pesavento, Giulia Pezzino, Petra Reinstadler, Carlo Ripoli, Silvia Savastio, Tiziana Timpanaro, Stefano Tumini, Gianni Vento
Abstract
CONTEXT: In the last decade the Sanger method of DNA sequencing has been replaced by next-generation sequencing (NGS). NGS is valuable in conditions characterized by high genetic heterogeneity such as neonatal diabetes mellitus (NDM). OBJECTIVE: To compare results of genetic analysis of patients with NDM and congenital severe insulin resistance (c.SIR) identified in Italy in 2003-2012 (Sanger) vs 2013-2022 (NGS). METHODS: We reviewed clinical and genetic records of 104 cases with diabetes onset before 6 months of age (NDM + c.SIR) of the Italian dataset. RESULTS: Fifty-five patients (50 NDM + 5 c.SIR) were identified during 2003-2012 and 49 (46 NDM + 3 c.SIR) in 2013-2022. Twenty-year incidence was 1:103 340 (NDM) and 1:1 240 082 (c.SIR) live births. Frequent NDM/c.SIR genetic defects (KCNJ11, INS, ABCC8, 6q24, INSR) were detected in 41 and 34 probands during 2003-2012 and 2013-2022, respectively. We identified a pathogenic variant in rare genes in a single proband (GATA4) (1/42 or 2.4%) during 2003-2012 and in 8 infants (RFX6, PDX1, GATA6, HNF1B, FOXP3, IL2RA, LRBA, BSCL2) during 2013-2022 (8/42 or 19%, P = .034 vs 2003-2012). Notably, among rare genes 5 were recessive. Swift and accurate genetic diagnosis led to appropriate treatment: patients with autoimmune NDM (FOXP3, IL2RA, LRBA) were subjected to bone marrow transplant; patients with pancreas agenesis/hypoplasia (RFX6, PDX1) were supplemented with pancreatic enzymes, and the individual with lipodystrophy caused by BSCL2 was started on metreleptin. CONCLUSION: NGS substantially improved diagnosis and precision therapy of monogenic forms of neonatal diabetes and c.SIR in Italy.