Staph in the nose is caused by a bacterium named Staphylococcus aureus, commonly called Staph. Staph is quite ubiquitous in normal life, and according to medical textbooks, "most newborns are colonized within the first week of life, 70 to 90 percent of adults' nasopharanyx are transiently colonized, and 20 to 30 percent of all adults carry Staph in nose at all times," according to the "Nelson Textbook of Pediatrics." In most individuals, colonization generally does not lead to infection; however, infection and colonization are often confused. Many symptoms caused by Staph in the nose are at sites away from the nose. Infections that are caused by Staph localized in the nose can be in combination with other symptoms at distant sites.
Colonization of the nose with S. aureus does not cause an active infection or local symptoms. True nasal infections as with S. aureus are generally secondary infections after a cold, flu, surgery, inflammation or other trauma to the nasal membranes that alters the normal first line of defense filtering provided by the nasal passages. Bacteria, like S. aureus, that normally only colonize the nasal passages are able to actively invade the local tissue and multiply, which triggers an immune response.
The presence of yellow to green mucus in the nasal discharge and throat is an indication of an active immune response. Other symptoms are nasal congestion or stuffy nose, sore throat, cough, fever and pain of the nasal membranes. With further invasion and inflammation, the sinuses become involved which results in headache, fever, chills, pressure along the sinus cavities (forehead, below eyes). The headaches typically change intensity with position and disappear shortly after getting out of bed.
Distant Skin Symptoms
Whether the nose is infected or colonized with S. aureus, the presence of S. aureus in the nose sets up for auto-inoculation of distant skin sites. These symptoms are pimples, furuncles or boils, carbuncles, impetigo, cellulitis and abscess. Pimples are simply pustules filled with pus that are located on the face, neck, upper back or chest. Furuncles, or common boils, are pustules or nodules that, unlike pimples, are painful. They are found anywhere on the skin, including inside the nose, and are marked by a circumscribed area of redness surrounding a central core. A carbuncle is a cluster of furuncles that form anywhere on the skin and cause "necrosis" or death of the surrounding cells with formation of drainage tracts or sinuses. Cellulitis is the inflammation of the soft or connective tissue caused by the S. aureus and involves a watery material "exudate" to spread through the tissue planes. Cellulitis can lead to ulceration or abscess. An abscess is a pus-filled cavity formed by the disintegration of the local tissue. These are quite painful and generally require drainage. Perianal abscess in one specific type that is found around the anal area. Impetigo is a skin infection that requires typically two triggers. The first is a break in the skin caused by a bug or chigger bite, scratch or cut. The second is the self-inoculation of the S. aureus from the colonization in the nose. The infection causes small pustules or vesicles that break early and leave a classic yellow dried crust or exudate. The lesions generally itch and the scratching continues to inoculate other areas.
Invasive Disease Symptoms
The invasive diseases caused by S. aureus from either the colonization or infection of the nasal membranes are life-threatening and need immediate medical intervention. Scalded skin syndrome, pneumonia, otitis media, endocarditis, oesteomylitis, meningitis, toxic shock syndrome, bacteremia and sepsis are examples. Many of these diseases are seen routinely in the pediatric population. Scalded skin syndrome is a red rash that looks the skin was scalded with hot water. Pneumonia is an infection of the lung with cough and fever. Otitis media in an infection of the inner ear behind the ear drum. Endocarditis is an infection of the heart inner lining. Osteomylitis is an infection of the bone. Meningitis is an infection of the lining covering the brain. Toxic shock syndrome is a systemic infection triggered in women using hyperabsorbent tampons. Bacteremia is bacteria in the blood stream that can cause all of the preceding symptoms, and sepsis is bacteria in the blood and other organs.