management

Last reviewed 11/2022

Consult expert advice.

Diphtheria antitoxin is only used in suspected cases of diphtheria in a hospital setting

• tests to exclude hypersensitivity to horse serum should be carried out
• diphtheria antitoxin should be given without waiting for bacteriological confirmation. It should be given according to the manufacturer's instructions, the dosage depending on the clinical condition of the patient

Diphtheria antitoxin is based on horse serum and therefore severe, immediate anaphylaxis occurs more commonly than with human immunoglobulin products

• if anaphylaxis occurs, adrenaline (IM or 1ml aliquots) should be administered immediately by either intramuscular (0.5ml of 1:1000 solution) or intravenous (1ml of 1:10,000) injection. This advice differs from that for treatment of anaphylaxis after immunisation because the antitoxin is being administered in the hospital setting

In most cutaneous infections, large-scale toxin absorption is unlikely and therefore the risk of giving antitoxin is usually considered substantially greater than any benefit

• nevertheless, if the ulcer in cutaneous diphtheria infection were sufficiently large (i.e. more than 2cm2) and especially if membranous, then larger doses of antitoxin may be justified

Antibiotic treatment is needed to eliminate the organism and to prevent spread. The antibiotics of choice are erythromycin, azithromycin, clarithromycin or penicillin

The immunisation history of cases of toxigenic diphtheria should be established. Partially or unimmunised individuals should complete immunisation according to the UK schedule

• completely immunised individuals should receive a single reinforcing dose of a diphtheria-containing vaccine according to their age

In the case of any outbreak then any carriers should be identified and treated with a one week course of penicillin or erythromycin. They should be kept in isolation until 6 daily throat swabs are negative.