Case 1: nurses in charge of a 6-year-old girl in a holiday camp noticed some blood spots on the girl's underwear. The possibility of sexual abuse was considered and the girl alleged that her father was responsible. The father was arrested. A surgeon was asked to examine the girl and planned to do it under general anesthaesia. Meanwhile, the girl was brought to the Forensic Medicine Unit. We found a normal hymen and no detectable anal lesions. The girl complained of dysuria and pollakiuria. Urinalysis revealed the presence of blood, leukocytes, and nitrite. Antibiotic treatment for lower urinary tract infection was initiated and all symptoms improved rapidly. The father was released. Case 2: a 7-year-old boy complained of having been sexually assaulted 24 h before. The boy did not report any pain or bleeding during or after the assault. Examination of the perianal region and of the anal sphineter were normal. Proctoscopy did not show any evidence of trauma to the anal canal. Tests to detect spermatozoa in the rectum were positive. The assailant was arrested. The present cases illustrate that: (i) psychological and social consequences of the biased interpretation of common symptoms may be dramatic in the case of child sexual abuse; (ii) both questioning and examining a child may be difficult for non-specialized practitioners; and (iii) tests to detect spermatozoa should be systematically performed in the case of a suspected or alleged recent assault, even in the absence of any clinical lesions.