Neurofibromatosis Type 1 Presenting With a Mesenteric Plexiform Neurofibroma and Epididymitis.

A 10-year-old male with a prior history of right epididymitis presented to the emergency department with a one-day history of right lower quadrant abdominal and right testicular pain. His initial examination was notable for café-au-lait macules and axillary freckling. An evaluation with renal ultrasound demonstrated mild left hydronephrosis, and subsequent testicular ultrasound was concerning for right epididymo-orchitis. A right lower quadrant abdominal ultrasound revealed a heterogeneous mass, and a CT of the abdomen and pelvis with and without contrast confirmed a large 14 cm × 16 cm × 16 cm hypoenhancing mass extending through the right lower mesentery and enveloping mesenteric vessels. An abdominal mass biopsy revealed a plexiform neurofibroma, and the patient met the criteria for neurofibromatosis type 1. He underwent resection of the plexiform neurofibroma, and further imaging revealed other neurofibromas. This case report highlights the importance of considering anatomic explanations for recurrent epididymitis in sexually naïve males and the importance of visual awareness during the physical examination, as neurocutaneous findings can influence the final diagnosis.