Melissa Kaplan's
Herp Care Collection
Last updated January 1, 2014

Treating Abscesses in Reptiles

©1996 Melissa Kaplan

Note
This is not a do-it-yourself manual on how to treat abscesses. It does discuss what needs to be done and I relate it from a personal perspective. But don't mess around with treating abscesses on your own until you have been shown how by a veterinarian or trained wildlife rehabilitator. You are cutting into a living animal, through skin and enervated and vascularized muscle tissue. You risk cutting tendons or joints and may cause worse problems than you started with. The treatment of abscesses is a surgical procedure and, like most surgical procedures, is best left to those who are trained in them, who can do them in a sterile field using sterile instruments and proper irrigation solutions, packing, wound dressing, and antibiotics - and anesthetics. Ask your vet if you may watch. Ask your vet to teach you how to do minor follow-up treatment at home. The more you learn the more you will be able to do...and the more you will realize how important it is that the procedures be done correctly. Check out the lists of herp societies and reptile vets if you don't already have a reptile vet.

Abscesses
Abscesses are interesting things... They do not necessarily occur at the site of an injury, and often do not occur in any proximity to an injury - they may form where there was no injury, and may form months after an injury was apparently well-healed.

Elbow abscess in a green iguana.

What is an abscess?
Abscesses are localized infections that generally occur in conjunction with systemic infections. The site may swell noticeably, or the abscess may reside well into the underlying tissue with little change in the skin above. Often there is a slight swelling which begins to ooze a yellowish liquid which may form a crust. As the skin stretches over the underlying swelling, the scales are moved farther apart and the skin in between may be seen. The skin may be reddish with petechia (burst capillaries) or crusty with dried serous fluid.

Why do abscesses form?
Generally speaking, bacteria that gets into a wound, say a minor scratch or puncture wound, from claws. The body's immune system is unable to successfully fight the invader off, and so the wound becomes infected, forming an abscess.

In healthy animals, the immune system marshals a defense and kills the bacteria before it can cause a problem, forming antibodies to recognize and fight it again.

A stressed animal has a weakened immune system. As it cannot as effectively fight off infections, some microorganisms will manage to proliferate to the point of causing illness. (This can happen to the normal load of gut microorganisms, which is how healthy reptiles end up needing to be treated for excessive loads of worms or protozoans.)

Captivity itself causes stress, no matter how perfect the captive environment and apparently well-adjusted the captive animal. Changes in the daily routine, introduction of a new household member or pet, moving to a new location, seasonal changes such as breeding season, etc., can affect the reptile's stress levels. Stress-related problems may follow relatively quickly, or may not manifest until weeks or months after the start of the stress period or stress event.

Stresses can include emotional stress such as being moved to a new enclosure, having the entire enclosure moved, changing owners, too cold, poor diet, breeding season, etc.

Treating Abscesses
Abscesses that occur in fleshy tissue can be lanced with a scalpel, the caseous pus removed using dental or bone curettes and swabs, and then flushed with an irrigation solution, such as 1% chlorhexidine diacetate (Nolvasan).

Even if all the caseous pus is removed from the site, and the site is kept open and irrigated daily and treated with systemic and topical antibiotics, more pus may form at the site, sometimes within a couple of days of the initial treatment. While this can happen even when the reptile is being given systemic antibiotics, it is more likely to occur when only topical antibiotics are given.

Failure to start antibiotic treatment may result in a worse infection if the site is not cleaned out thoroughly. Even when on antibiotics, particularly resistant infections may cause repeat abscesses to grow. This is because, even though the antibiotics used first are broad-spectrum (effective against a wide range of bacteria), the bacteria causing the infection may not be responsive to that particular antibiotic.

Resistant Infections
If using Baytril (enrofloxacin) is being used, the usual dose of 5-10 mg/kg daily for 10 days can be doubled, either giving 10-20 mg/kg SID or 5-10 mg/kg BID for 10 more days.

If the infection remains resistant, a culture should be done, with a piece of the caseous pus sent out for culture and sensitivity. This takes a couple of weeks, but will identify the organism and the best antibiotic to use in treating it.

Abscesses in bony areas (such as jaw, eye area or joints) may cause further problems, especially if left untreated for some time. Not only can they affect the mobility of the joint and adversely impact the animal's use of that limb, it can eat away at bone and cartilage; this can get very expensive surgically and radiographically. It is best to treat such abscesses as soon as possible, with antibiotics and aspiration (if loose pus or fluid) or lancing and excision (caseous pus).

Pre-Treating with Systemic Antibiotics
There are times when, upon opening the abscess site, it is found that the caseous material has not formed a consolidated lump, the vet may remove what he can, and then close the wound and begin a 10 day course of systemic enrofloxacin. This antibiotic is especially good at reducing the blood flow to the abscess and causing it to consolidate, both of which make it easier to remove and decrease the likelihood of its reformation at the site. Depending on the vet's assessment of the situation when he goes back in to remove the remaining pus, the reptile may or may not be prescribed another course of systemic antibiotic therapy.

The antibiotics generally used are Baytril (enrofloxacin), Piperacil (piperacillin), and Amikacin (amiglyde sulfate). While Amikacin is particularly nephrotoxic and must be administered with supplemental fluids, green iguanas should receive supplemental subcutaneous or intracoelomic injections of fluids whenever given any antibiotic.

Piperacil can cause tissue necrosis around the injection site and so should be diluted with saline or lactated ringers. Baytril can sting going in and if administered subcutaneously, it too can cause painful tissue necrosis in some species. Baytril injectable can be administered by mouth and it can also be obtained in tablet form. Talk to your vet about diluting the Baytril by drawing up saline into the syringe before injecting to reduce the sting and potential necrosis.

Non-Bacterial Abscesses
In animals prone to lungworm infestation (primarily fish eaters), as well as some other species, abscesses may in fact be larvae or adult worms trying to migrate out. The way they spread is to cause a subdermal irritation which generally causes the host animal to scratch at it or rub it against something, causing the "abscess" to break open, thus freeing the parasite who then looks for another host in which to complete it's life cycle.

Working with Abscesses
When working on abscesses, wear disposable surgical gloves, have your Betadine or Nolvasan solutions ready at hand, your gauze sponges, sterile swabs and and other necessities close at hand. It is best to work with someone else who can keep the animal wrapped and restrained while you use both your hands to accomplish what needs to be done.

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