Acute urinary retention (AUR) in young adults is an uncommon presentation often signalling an underlying pathology, particularly when associated with genetic conditions like neurofibromatosis type 1 (NF1). We report the case of a 25-year-old male with a known family history of NF1, who presented with acute urinary retention and progressive pelvic pain. This evidence concerns the gene NF1 and neurofibromatosis type 1.