Is my Wound Created by a Spider Bite?
Yadwinder Dhillon, MD, is a physician at Banner Good Samaritan Medical Center.
Question: I have a wound on my leg and suspect it is from a spider bite. It’s been two months and the area does appear to be healing. What should I do?
Answer: Wounds caused by venomous or infectious bites need medical attention. In the short term, the best thing to do is keep the area clean and bandaged. You can wash the wound with soap and water daily, and apply some antibacterial cream to keep the area moist and free from infection. Depending on the size and location of the wound, a physician may recommend special wound care products, and may need to clean the wound using special instruments to reduce the amount of bacteria and remove any dead tissue that may be impeding the healing process.
There are many spiders in Arizona that have a venomous bite. The Arizona Brown Spider and the Black Widow are two commonly known spiders whose bites can result in actual tissue death. The bite itself is usually not felt, and only noticed once skin changes begin to occur.
The venom from the bite will cause cells within the tissue to rupture and die within the area of the bite. This will cause the body’s defensive mechanism to turn on, and cause inflammation and pain at the sight. The cycle continues for some time, causing the wound to increase in size and show the true depth of damage.
Another cause of non healing wounds is infection. Almost all insects, including spiders, pick up bacteria which live on the fangs of the insect. When they bite, it can inject the tissue with the bacteria that causes an infection. The body may not be able to completely kill the bacteria which results in a low level infection in an expanding wound. The time it will take for the wound to heal will depend on the type of bacteria and the person’s ability to heal, as not everyone heals at the same rate.
The body’s immune system reacts in a way to fight off the foreign material injected by the insect. If the body’s reaction gets out of control, or the body is not able to control the damage, it becomes a chronic wound. Depending on the location on the body of the wound and the person’s health, certain wounds may take longer to heal. In general a wound should show 50 percent reduction in size within a month, otherwise it is considered non-healing. With good care, all wounds should heal with time.