The paper reports the case of an 8-year-old boy with type 1 diabetes mellitus and celiac disease who presented to the Emergency Room with bilateral periorbital oedema, low-grade fever and cough. Workup revealed nephrotic syndrome (nephrotic-range proteinuria, hypoalbuminemia, dyslipidemia), along with a respiratory infection due to Mycoplasma pneumoniae and rhinovirus. Autoimmune and infectious evaluations were negative except for Mycoplasma. Given the spontaneous improvement without immunosuppressive therapy, a conservative approach was chosen. The clinical course supports the hypothesis of secondary podocytopathy triggered by Mycoplasma pneumoniae infection.