Methicillin resistant Staphylococcus aureus or MRSA
(False spider bite diagnosis):

In the last 2 years clinicians have noticed a gross increase in MRSA. This author has personally noticed an enormous increase in this diagnosis in the last 7-10 months in the Northern Illinois area. Some speculate that the reason is due to the fact that clinicians are culturing wounds more frequently. Others believe that this is an emerging disease state.

Staphylococcus aureus is a very common organism. We are seeing an increase in the Methicillin resistant strain. Typical culture and sensitivity results on Methicillin resistant Staphylococcus aureus:

Amox-Clavulanate - resistant

Cephalosporins - resistant

Ciprofloxacin - sensitive

Clindamycin - sensitive

Erythromycin - sensitive

Gentamicin - sensitive

Levofloxacin - sensitive

Penicillin - resistant

Rifampin - sensitive

Trimethoprim/sulfa - sensitive

Vancomycin - sensitive

Side note: Rifampin should not be used alone for chemotherapy. Please consult Sanford guidelines.

Signs & symptoms of MRSA

When these lesions present, they are usually very red. They can be the size of a quarter, half dollar or silver dollar. They are commonly found on the extremities. They are indurated and can be fluctuant to touch. It appears to look like abscesses or a spider bite. Very commonly confused with a spider bite. They may be ulcerating in the center. They can occur in anyone in the population. I have seen them on young children playing soccer. They can be passed between different family members. It is not uncommon for the MRSA organism to colonize in the nasal passages.

MRSA Treatment

Healthcare provider treatment

1. Do not diagnose a spider bite if you are unsure and the person does not bring in or see the spider near them.
2. Look at the geographical location. If you are in northern sections of the United States, it is very unlikely that you are going to be bitten by a brown recluse spider. Brown recluse spiders are more prevalent in the South and in warmer climates.
3. These wounds should be I & D'd. C & S (culture & sensitivity) needs to be performed on all of the individuals can be started on a Cephalosporin. However if you are questioning a MRSA diagnosis, you can go ahead and start the patient on Ciprofloxin.
4. After consulting with an infectious disease specialist, they advise that once MRSA has been diagnosed, never prescribe Ciprofloxin alone. Use in combination with Clindamycin.
   In cases of recurrent MRSA in the same patient or household, Chlorohexadine sponge baths twice a day for a week, all chairs, couches, bed linens, sheets, even the car headrests and seats need to be cleaned.
5. Bactroban Mupirocin cream should be used intranasally twice a day for 5 days, as well as the combination chemotherapy as previously discussed. Close follow-up is imperative with frequent wound care and packing.
6. Close observation for lymphangitis is important in acceleration of the infection.

Once again, be careful not to confuse these with spider bites.