Staphylococcal bacterial skin infections, Methicillin Resistant Staph, and New Skin Treatments

While attending one of the largest veterinary conferences in the world, a few glaring and concerning facts were presented about the state of antibiotics in the human and veterinary worlds. One of the most common challenges I have faced each day in the last 10 years has been Staphylococcal skin infections obtained after scratching or itching. Recently, it has been noted that many of these infections have become resistant in cultures to some of the more commonly prescribed oral and injectable antibiotics. 

WHY HAS ANTIBIOTIC PRODUCTION DECREASED 75% since 1983 IN THE USA?

There is not a lot of profit behind the development of new, occasional-use antibiotics versus the daily use of cholesterol lowering drugs (statins) that people take each day. Government agency guidelines recommend antibiotic use to be limited to only to severe cases, and that limits the ability of manufacturers to recoup costs. Used appropriately, antibiotics should be used for specific, targeted, bacterial infections and for a short period of time. 

 WHAT IS THE DIFFRENCE BETWEEN THE STAPHYLOCCOCAL DRUG-RESISTANT SKIN INFECTIONS OF PEOPLE VERSUS THOSE IN DOGS?

Dogs have Methicillin-Resistant Staphylococcal Pseudintermedius (MRSP) and people have Methicillin-Resistant Staphylococcal Aureus (MRSA). They are not felt to be of  concern in cross infections unless an individual is going through chemotherapy, incurs severe bite wounds, or has a compromised immune system. MRSP was first noted in North America in 1999 and MRSA in 1961.

ARE THERE SOME CLASSICAL SIGNS OF STAPH SKIN INFECTIONS IN DOGS?

They often look like circular lesions, similar to that expected with fungal infections (ringworm).  Some are itchy; others start as a pimple (infected hair follicle) then spread out like the ripple created when a pebble hits a pond.

TOPICAL THERAPY IS REALLY BEING PUSHED IN THE TREATMENT OF SURFACE INFECTIONS. 

One of the biggest reasons for topical antiseptic therapy is because there has been no drug resistance reported to date. In the past they were considered adjunct treatments (used in addition). Now they are being recommended instead of antibiotics (except in extreme cases) since there are no new antibiotics for skin infections currently available. Topicals can kill even highly antibiotic-resistant bacterial strains. They must initially be applied daily.  Below is a picture of the Staphylococcal  groin infection (featured at right) at 2.5 weeks post treatment with topical therapy alone. 

NAME SOME EXAMPLES OF TOPICAL ANTIBACTERIAL PRODUCTS. Alternative ones?

Douxo Chorihexiderm shampoo, spray, mousse are excellent products. Others are using malaket anti-septic wipes,

mupirocin cream, and a novel product from the dairy industry to disinfect udders, Preva wipes. 

YOU MENTIONED PREVA WIPES. WHAT MAKES THEIR TOPICAL USE UNIQUE COMPARED TO OTHER WIPES?

From Bayer Animal Health, they are unique in that they contain Nisin, a naturally derived antimicrobial from Lactococcus lactis. It is a 6x8 inch wipe and is utilized as an adjunct, in-between treatment to shampoos and topical leave-on antiseptics.

HOW OFTEN WILL THE TOPICAL ANTISEPTIC SPRAYS, LOTIONS, OR LEAVE-ON MOUSSE NEED TO BE APPLIED TO INFECTED SKIN AREAS?

Daily topical skin application is required until healed. Then once-a-week application is necessary.

IS THERE A WAY OWNERS KNOW THE SKIN INFECTION HAS DRUG RESISTANCE AND MAY STILL NEED ORAL ANTIBIOTICS?

A skin culture. 

WHY ARE ESSENTIAL FATTY ACIDS SUCH AS FISH OIL PRESCRIBED?

It is believed they have weak anti-inflammatory effects and may help boosts the outer skin layer function (epidermal barrier). In addition, this may lower the dose of oral anti-histamines and steroids due to lower itching. 

THERE IS A LOT ONLINE ABOUT EPIDERMAL BARRIER FUNCTION AND TOPICAL PIPETTE PRODUCTS SUCH AS DOUXO ANTI-SEBORRHEIC OR THE ALLERDERM LINE. HOW IS THIS SPECULATED TO WORK?

Topical lipid emulsion preparations may normalize the outer skin barrier and inflammatory leaking between cells of the epidermis that perpetuate itching, odor, and secondary infections due to allergies.

ARE THERE ANY OTHER FACTORS THAT INCREASE THE RISK OF DRUG RESISTANT SKIN INFECTIONS?

Hospitalization, surgery, prior antibiotic use in the last 30 days, or the repetitive use of antibiotics. 

IS THERE A BIG LESSON HERE?

When possible, perform a cytology for yeast and bacteria, a skin scrape for mange, and  fungal cultures for any significant skin infections. In repetitive infections, culture the skin and look for underlying causes.  Washing your hands several times a day and pets once a week is also an excellent recommendation.

New treatments such as probiotics to create healthy bacterial environments that overgrow the bad bacteria and the research of viruses that kill bacteria (phages) are on the horizon.  Some guidelines are noted in hwww.wormsandgermsblog.com/files/2008/03/vde121181.pdf

HOW SERIOUS ARE DRUG-RESISTANT INFECTIONS IN THE USA?

The CDC reports a minimum of 23,000 people die each year as a direct result.  100,000 die from related complications.  Two million people contract such infections each year. Yet, over half of the antibiotics prescribed are considered unnecessary. In summary, drug- resistant bacteria and viruses are considered the sixth leading cause of death in the USA, and the numbers are rising. 

Betsy T. Sigmon, DVM, Diplomate ABVP, Canine & Feline

Hospital Director

Creature Comforts Animal Hospital

Cary, NC

BIG VAROOM FOR RAY PRICE HARLEY DAVIDSON AND BIKER BOOT CAMP YESTERDAY. In addition, special thanks to Ms. Ray Price for her hospitality and the courteous treatment of all attendees by her employees. 

Yes it is winter in all its glorious beauty!