Staphylococcal bacteria commonly inhabit the skin and interior of the nose. Microscopic or visible breaks in the surface barrier of the body--the skin and mucous membranes--provide an opportunity for these bacteria to cause localized infections. Complications arise when the staph bacteria spread beyond the initial site of infection to the bloodstream and interior body tissues. Complications of staph infections can be life-threatening.
Types
Localized staph infections--such as boils, impetigo and wound infections--that spread to the bloodstream can potentially cause an infection in any body organ. Common sites of complicating, or secondary, staph infections include the heart, lungs, bones, joints and muscles, reports the medical reference text "Principles and Practice of Infectious Diseases."
Staphylococcal toxic shock syndrome is an uncommon but potentially deadly complication of staph invasion of the bloodstream, or bacteremia. With this condition, the bacteria trigger an overwhelming immune response that leads to falling blood pressure and subsequent oxygen deprivation in the body tissues. Kidney and liver failure often ensue with persistent low blood pressure.
Signs and Symptoms
Fever and chills typically develop when a localized staph infection spreads to the bloodstream, reports MayoClinic.com. The heart rate usually increases and the patient commonly exhibits decreased mental alertness. Blood cultures, a test to determine the presence of bacteremia, demonstrate staph bacteria in the bloodstream.
Localized signs and symptoms indicate the invasion of specific body organs. People with bacterial seeding of the lungs develop symptoms of pneumonia, including shortness of breath, cough and production of phlegm. Severe joint pain and swelling are signs of joint infection, or septic arthritis. Signs of infection of the interior of the heart, or endocarditis, include purple spots on the skin of the arms and legs and abnormal heart sounds heard when listening with a stethoscope.
Symptoms of toxic shock syndrome include a high fever, confusion, diarrhea, vomiting, headache, muscle aches, sore throat and a bright red skin rash that resembles a sunburn. The blood pressure is characteristically low and generally does not increase with the administration of intravenous fluids, reports the Centers for Disease Control and Prevention.
Risk Factors
Complications of a staph infection can occur in anyone. People with underlying conditions that cause generalized debilitation and a weakened immune system, however, may be at increased risk. MayoClinic.com reports that hospitalization, diabetes, kidney dialysis and recent surgery increase the risk for staph infections and potential complications.
Treatment
Antibiotics are the primary form of treatment for a complicated staph infection. The choice of antibiotic depends on the susceptibility of the causative bacteria to specific antibacterial drugs. Many complicated staph infections are caused by methicillin-resistant Staphylococcus aureus, or MRSA. MRSA bacteria are resistant to several antibiotics. Special consideration is required in determining the appropriate antibiotic to treat a MRSA infection.
Significance
From 1999 through 2005, the rate of complicated staph infections requiring hospitalization increased dramatically in the United States, report Eili Klein, M.A., and colleagues in a 2007 article published in "Emerging Infectious Diseases." During the study time frame, approximately 10,800 Staphylococcus aureus-related deaths occurred annually in the United States.
References
- "Principles and Practice of Infectious Diseases, Sixth Edition"; Gerald L. Mandell, M.D., et al., Editors; 2004
- MayoClinic.com: Staph Infections
- U.S. Centers for Disease Control and Prevention: Toxic Shock Syndrome
- "Emerging Infectious Diseases"; Hospitalizations and Deaths Caused by Methicillin-Resistant Staphylococcus aureus, United States, 1999-2005; Eili Klein, M.A. et al.; December 2007
- MayoClinic.com: Toxic Shock Syndrome
