The members of human Herpesviridae family are fully acknowledged as pathogenic agents in immunocompromised individuals, often responsible for a number of severe diseases. On the other hand, in immunocompetent hosts, Herpesviridae-related infections typically display an asymptomatic or paucisymptomatic course, sometimes manifesting with flu-like symptoms. However, such infections can occasionally cause organ damage or multisystemic involvement in healthy subjects. Herein, we describe the first case of a simultaneous co-infection by five different Herpesviridae family members in an apparently immunocompetent young subject. A 30-year-old Caucasian man presented to our medical unit with colitis. During hospitalization, he developed multi-organ damage involving heart, pancreas and liver. Quantitative polymerase chain reaction analysis showed positive results for cytomegalovirus, Epstein-Barr virus, human herpes virus 6, human herpes virus 7, and human herpes virus 8. Remission of clinical manifestations and complete negativization of viral load were achieved by antiviral therapy. To the best of our knowledge, such simultaneous infection by multiple herpesviruses causing a severe multi-organ dysfunction has never been described in patients with preserved immune function. Careful literature review showed that organ damage in immunocompetent subjects was reported in very few cases of co-infection by two herpesviruses, and in only one case of co-infection by three herpesviruses. Multi-organ damage in our patient likely resulted from additional effects induced by Epstein-Barr virus, human herpes virus 6, human herpes virus 7, and human herpes virus 8, through either a superinfection occurring after initial cytomegalovirus disease, or a simultaneous co-infection of the different viral agents. Moreover, the possibility of a transient and partial immune dysfunction, predisposing the patient to develop a severe herpesvirus-associated disease, cannot be completely ruled out. Although a formal indication to antiviral therapy has not been established in herpesvirus-infected immunocompetent individuals, our case supports the usefulness of such therapy in case of severe multisystemic clinical manifestations. This original case report suggests that the possibility of multiple herpesvirus simultaneous infections should be taken into account in differential diagnosis for severe organ dysfunction, also in apparently immunocompetent subjects.