Statistically, the most likely diagnosis for the patient considered here is testicular torsion; however, the other possibilities cannot be ruled out. Sudden onset of pain is more characteristic of testicular torsion than appendiceal torsion or epididymitis, whereas the onset of pain for the latter two conditions tends to occur more gradually (Kass and Lundack, 1997)
Every effort should be made to gather a complete urologic and surgical history for the patient to exclude other conditions, including a urinary tract infection and epididymitis. A recent study examined the diagnosis distribution for 388 boys under the age of 17 who were treated at the Hospital for Children and Adolescents in Helsinki between 1977 and 1995 for acute scrotum (Makela, Lahdes-Vasama, Rajakorpi, and Wikstrom, 2007)
The cremasteric reflex should be examined by stroking or gently pinching the medial thigh, but this should be done with the unaffected side first to establish a baseline. An absent cremasteric reflex for the affected testicle is a strong, but not absolute indication of testicular torsion (Nelson, Williams, and Bloom, 2003)
The febrile state of the patient could indicate epididymitis, but the absent cremasteric reflex and swollen testicle is most consistent with testicular torsion. Although ultrasound or radionuclide imaging could be informative, the absent reflex and swollen testicle is sufficient justification to surgically explore the affected testicle (Ringdahl and Teague, 2006)