In cases of suspected or diagnosed diphtheria, the first step is admission of the patient to an isolation ward to prevent the spread of this highly contagious disease to other people.
The treatment of diphtheria can be divided into two main approaches: the use of antibiotics to eradicate the diphtheria infection and the use of diphtheria antitoxin to neutralize the effects of the bacteria’s toxins. In addition, the grey–white membrane that forms across the back of the throat and tonsils may need to be removed if it is obstructing breathing.
Most people who have caught diphtheria only require a two week course of antibiotics, after which they will be tested to see if the infection has cleared up. If the diphtheria bacteria are still detected, a further 10-day antibiotic course may be prescribed. The antibiotic dose prescribed will depend on the severity and duration of the diphtheria infection. The patient is discharged from the isolation ward only after the tests show no sign of the infection. The patient should then be vaccinated against diphtheria as a previous infection does not protect against future infection.
Due to the highly contagious nature of the infection, all people who are known to have come into close contact with an individual infected with diphtheria should be tested for the infection. Usually a swab is taken from the person’s nose and they are given antibiotics if they have the infection.
Treating cutaneous diphtheria
This form of diphtheria affects the skin and is treated by thoroughly washing any infected wounds with soap and water. Tests are repeated two weeks later to check the bacteria are no longer present.
Treating diphtheria emergencies
Examples of emergencies that may arise in cases of diphtheria are breathing difficulties and myocarditits (inflammation of the heart muscles). Breathing difficulty may develop due to obstruction caused by the membrane that grows across the inside of the throat. In addition, small pieces of the membrane can break off and fall into the lungs, causing them to inflame and even giving rise to loss of lung function and respiratory failure. Patients at risk of respiratory failure are connected up to a ventilator which will keep the lungs supplied with oxygen while the infection is treated.
The toxin produced by the diphtheria bacteria can cause myocarditis. This condition can lead to an irregular, very slow heart beat called bradycardia that may require a temporary pacemaker to normalize the heart’s rhythmn.
The diphtheria antitoxin is given to neutralize the effects of the toxin produced by the diphtheria bacteria, which can cause paralysis of muscles in the eye, lungs , throat and neck. The antitoxin cannot neutralize toxin that is already bound to tissues but can neutralize circulating (unbound) toxin.
Skin allergy tests may be performed to check for sensitivity to the antitoxin before it is given. Allergic individuals need to be desensitized to the antitoxin which is achieved through the administration of initial small doses that are increased over time.
Reviewed by Sally Robertson, BSc