-In temperate climates, Diphtheria usually involves the respiratory tract
–Occurs throughout the year, with peak in colder months
-Prior to immunization, devastating epidemics in children -> mortality rates were up to 50% during epidemics

-Cases Reported:
–In 1921: >206,000 cases reported
–Between 1980-1987: only 22 cases reported
–Currently, only 5 cases/yr in US

-Immunzation Status:
–Currently, 20-25% of older adults are susceptible to Diphtheria
–Most cases occur in non-immunized patients
–Attack rate/severity/risk of complications are much lower in immunized patients

1) 1969-1970: San Antonio
2) 1972-1982: Seattle, WA -> 86% of the 1100 cases were cutaneous Diphtheria

-Risk Factors in Outbreaks:
1) ETOH Abuse:
2) Low Socioeconomic Status:
3) Crowded Living Conditions:
4) Native American Ethnicity:
5) Homosexuality: noted in outbreak in England with tox-negative strains






(multiple sites of respiratory tract involvement may occur)

Tonsillopharyngeal Diphtheria

Laryngeal Diphtheria

Nasal Diphtheria



Cutaneous Diphtheria

Conjunctival Diphtheria (uncommon)

GU Tract Diphtheria (uncommon)

GI Tract Diphtheria (uncommon)


Polyneuritis (see [[Peripheral Neuropathy]])


Diphtheria Anti-Toxin:
-Produced from horse serum
-Indicated for respiratory Diphtheria cases -> although, may withhold in cases that are toxin-negative
-Role in treating cutaneous Diphtheria is unclear
-Pseudomembrane may continue to increase in size for the first day after anti-toxin administration -> resolves over days-1 week
-SE: serum sickness (10% risk)

Antibiotics: main role is to eradicate organism and prevent transmission (since antibiotics do not significantly enhance healing in local infection cases that have been treated with anti-toxin)
1) Erythromycin:
2) PCN-G:
3) Clinda:
4) Rifampin:

Supportive Care:
1) Intubation/Mechanical Ventilation: indicated for laryngeal involvement and/or airway obstruction
2) EKG Monitoring/Treatment of Arrhythmias and Heart Blocks:
-DL-Carnitine: unclear role, but may be beneficial in myocarditis

Treatment of Skin Lesions:
1) Burow s Solution Compresses After Debridement: