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Medical Author:

Steven Doerr, MD

Steven Doerr, MD

Steven Doerr, MD, is a U.S. board-certified Emergency Medicine Physician. Dr. Doerr received his undergraduate degree in Spanish from the University of Colorado at Boulder. He graduated with his Medical Degree from the University Of Colorado Health Sciences Center in Denver, Colorado in 1998 and completed his residency training in Emergency Medicine from Denver Health Medical Center in Denver, Colorado in 2002, where he also served as Chief Resident.

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Medical Editor:

Charles Patrick Davis, MD, PhD

Charles Patrick Davis, MD, PhD

Dr. Charles "Pat" Davis, MD, PhD, is a board certified Emergency Medicine doctor who currently practices as a consultant and staff member for hospitals. He has a PhD in Microbiology (UT at Austin), and the MD (Univ. Texas Medical Branch, Galveston). He is a Clinical Professor (retired) in the Division of Emergency Medicine, UT Health Science Center at San Antonio, and has been the Chief of Emergency Medicine at UT Medical Branch and at UTHSCSA with over 250 publications.

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The symptoms and signs of respiratory diphtheria may initially be similar to a viral upper respiratory infection, however, the symptoms become more severe with the progression of the disease. Generally speaking, individuals exposed to diphtheria begin to experience symptoms between two to five days after the initial infection, though some individuals may not experience any symptoms at all (asymptomatic). The symptoms and signs of respiratory diphtheria may include the following:

• Sore throat



• Fever



• Hoarseness



• Difficulty swallowing



• Malaise



• Weakness



• Headache



• Cough



• Nasal discharge (that may contain pus or blood-tinged fluid)



• Enlarged lymph nodes in the neck and neck swelling (producing a "bull neck" appearance)



• Difficulty breathing

As respiratory diphtheria progresses, individuals may develop the classic adherent thick, gray membrane (pseudomembrane) forming over the lining tissue of the tonsils, pharynx, and/or nasal cavity. Extension of this pseudomembrane into the larynx and trachea can lead to obstruction of the airway with subsequent suffocation and death. See reference two for pictures of the bacteria and the pseudomembrane.

The systemic manifestations of diphtheria are caused by the effects of the diphtheria toxin and its subsequent dissemination to other organs away from the initial area of infection. Commonly affected organs include the heart and nervous system, leading to complications such as inflammation of the heart (myocarditis), cardiac rhythm and conduction disturbances, muscle weakness, numbness (nerve), and vision changes.

Cutaneous diphtheria is characterized by an initially painful red lesion that eventually becomes a non-healing ulcer covered with a gray-brown membrane. This mild localized infection is only rarely associated with systemic complications.

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