ABSTRACTNecrotizing descending mediastinitis is an emergency which can be fatal in most cases. 80% to 85% of patients who develop descending necrotizing mediastinitis are young, previously healthy persons. We present the case of a healthy patient who, after a neck abscess, de-veloped descending necrotizing mediastinitis complicated by atypical interstitial pneumonia.KEYWORDS: mediastinitis, lung diseases, interstitial, case repor