Necrotizing fasciitis is one of the most dangerous complication of an abscess and it is still a disease with a high mor- tality. In this work, we decided to consider two cases: the first one concerns a male subject, aged 66, deceased because of a fatal necrotizing fasciitis associated to a cervical descending mediastinitis, which evolved from a primary periton- sillar abscess; the second is about a 50-year-old woman with a perineal abscess, then evolved into necrotizing fasciitis associated to a fatal septis shock. After a systematic consideration of necrotizing fasciitis as pathology and an analysis of the possible related risks to a diagnostic or therapeutic delay, we analyzed the particular history of both cases to under- line the possible critical issues in professional behavior of the medical staff intervened.