Question

Jamie is a 48-year-old black woman who comes into the emergency department complaining of painful swelling, drainage, and redness over the past 5 days in the left hand. She spends a lot of time outdoors working in her garden and said she had a “pretty nasty” mosquito bite on the top of that hand before the swelling started. After 3 days of increased swelling and redness she went to her doctor and received an oral antibiotic and was told it was probably a mild infection from the insect bite. Now, she presents because her hand is increasingly painful, tight, and the drainage has worsened. She noticed that she had a fever this morning of 102.9°F. Laboratory test results today show a WBC count of 18,500 (well above normal). The wound is cultured and is found to be positive for Staphylococcus aureus, which is a bacteria commonly found on the skin as a communal organism.  

1. It started as a bug bite on the epidermis but has developed into a cellulitis. Explain in detail what happened.

Answer 1

From the given scenario it looks like while Jamie was working in the garden, she got massive mosquito bite which she considers "pretty nasty". As a result, her immune system started responding to the attack of foreign body causing swellness and redness. In the course of three days, the puncture in the skin got infected by Staphylococcus aureus. In the whole staphylococcal bacterium family, Staphylococcus aureus is a type of bacteria that is considered the most dangerous and is often responsible for skin infection. It usually causes abscesses, redness, itchiness and swelling in the infected region. It is a highly communicable bacteria which can spread through direct contact with an infected person, or through droplets in the air or contaminated objects. Hospitals are most likely to spread these bacteria as they are usually observed on the surface of the contaminated medical equipments. May be this was the reason for further infection in the case of Jamie. After getting the skin infection from Staphylococcus aureus, she developed cellulitis. This happened because the mosquitoes breaked the skin surface of Jamie's hand through which Staphylococcus aureus entered the small puncture point and develop into a severe infection. Usually administering antibiotic medication make these conditions disappear in a few days but with the death of the bacteria, substances that cause tissue damage are released which causes further pain, tightness, and drainage. Sometimes, when the developed cellulitis is severe, it does not respond to the normal antibiotic as well and other strong interventions are required. Her WBC count of 18,500 and body temperature of 102.9°F indicates that her body's immune system is fighting very hard to kill the pathogen and get rid of the infection.