Cellulitis is a bacterial infection of the deep layers of the skin, most commonly caused by the bacterium group A streptococcus or Staphylococcus aureus. The legs and face prove the most common sites of cellulitis. An abscess is a localized area of infection that forms a pocket of pus, dead tissue and the infecting organisms, which may be bacteria, fungi or parasites. Abscesses may form in any soft body tissue. Cellulitis and abscesses can lead to serious, potentially life-threatening complications. Medical attention is required for both conditions.
Bacteremia
Both cellulitis and abscesses may lead to the spread of the infection to the bloodstream, a condition known as bacteremia. The bacteria traveling through the blood may seed other organs, causing the formation of one or more abscesses, notes "The Merck Manual for Healthcare Professionals."
Bacterial seeding of the heart valves may cause endocarditis, which can lead to permanent structural damage. Other sites that may be infected include the spinal fluid, abdominal cavity, heart sac and the large joints. Bacteremia caused by certain strains of bacteria may lead to sepsis, a systemic response to infection that can progress to shock and potentially death.
Infectious Gangrene
Infectious gangrene is a rapidly progressive form of cellulitis, characterized by an expanding area of tissue death. A variety of bacteria can cause infectious gangrene, including group A streptococcus, Clostridium species, Pseudomonas aeruginosa, Proteus species and Staphylococcus aureus, reports the medical reference text "Principles and Practice of Infectious Diseases." Infectious gangrene caused by Clostridium perfringens is commonly known as gas gangrene.
Group A streptococcal gangrene frequently invades the tissues beneath the deep skin, a condition known as necrotizing fasciitis. The level of swift and extensive tissue destruction caused by group A streptococcal necrotizing fasciitis has led to the moniker of "flesh-eating bacteria" to describe this condition.
Disfigurement can be extensive with infectious gangrene, including limb amputations. Bacteremia and sepsis associated with infectious gangrene may prove life threatening.
Brain Abscess
Cellulitis or an abscess that causes bacteremia may seed the brain, leading to the formation of a brain abscess. The development of a brain abscess is a potentially life-threatening complication. A brain abscess grows quickly, causing rapidly increasing pressure, notes the patient information website InteliHealth. Brain swelling in response to the abscess further increases the intracranial pressure.
Without urgent treatment, the elevated pressure associated with a brain abscess may push the brain through the bony opening in the skull for the spinal cord. This condition, known as brainstem herniation, is often fatal. Urgent treatment for a brain abscess may include antibiotics, brain surgery or both.
References
- Merck Manual for Healthcare Professionals: Bacteremia
- "Principles and Practice of Infectious Diseases, Sixth Edition"; Gerald L. Mandell, M.D., et al., Editors; 2004
- InteliHealth: Brain Abscess
- Merck Manual for Healthcare Professionals: Cellulitis
- Merck Manual for Healthcare Professionals: Abscesses
