A Relapsing Acute Tubulointerstitial Nephritis as an Expression of a Kappa Light Chain Multiple Myeloma: A Case Report. - Angioi, Andrea; Lepori, Nicola; Floris, Matteo; Cheungpasitporn, Wisit; Bianco, Paola; Cabiddu, Gianfranca; Pani, Antonello (Case Reports in Nephrology & Dialysis, 2025)