[Can the isolation of nontoxigenic strains of Corynebacterium serve as a basis for establishing a diagnosis of diphtheria?].

It is suggested that isolation of nontoxigenic strains of diphtheria corynebacteria is a bacteriological proof of the diagnosis. Underestimation of the epidemiological situation, presence of nontoxigenic corynebacteria in a patient with angina may result in fatal errors.