Infectious Disease Compendium

Diphtheria

Diagnosis

Sore throat, grey bleeding pseudomembranes, myocarditis and neuropathy with toxigenic strains. Can be nasal, pharyngeal or tonsillar diphtheria.

Non toxigenic strains can cause focal infections anywhere.

Should see an adherent, dense, grey pseudomembrane covering the posterior aspect of the pharynx.

Cutaneous diphtheria is a disease of chronic ulcers of the extremities (PubMed). Look for it in the homeless alcoholic. It can also be found in travelers to tropical areas (PubMed) where C. ulcerans is a common cause (PubMed).

Epidemiologic Risks

Human to human.

Microbiology

C. diphtheriae and other Corynebacterium.

Empiric Therapy

Penicillin OR erythromycin AND antitoxin 20,000 to 40,000 units for pharyngeal or laryngeal disease of 48 hours' duration; 40,000 to 60,000 units for nasopharyngeal lesions; 80,000 to 120,000 units for extensive disease of 3 or more days' duration and neck swelling.

Anti-toxin is available from the CDC.

Pearls

Diphtheria toxin is produced by C. diphtheriae only after infected by a bacteriophage that integrates the toxin-encoding gene into the bacteria. Occasionally other Corynebacterium can be transformed as well to become toxin producers.

Rants

There is this vaccine that prevents the illness. It is way cool, it prevents people from dying. In the old USSR they quit using the vaccine and large numbers of young children died in subsequent outbreaks. The anti-vaccine people (aka pro death from infection) are wrong. Well, simple maybe. I look forward to your e-mail.

Last Update: 06/21/18.