The purpose of this post is to make Rhac keepers aware of an unusual problem that affects Crested Geckos. I had read on this forum just a few days ago, a telltale story that parallels what I experienced. That person lost his male Crested for “unknown” reasons. While we’ll never know if what happened to his gecko is related, there is certainly a high degree of probability that it may be based on his description.

Early this fall I received 4 Crested Geckos from a breeder/dealer. Outwardly all 4 appeared healthy (with one being considerably larger than the other three). But as with all new animals, these 4 were placed in quarantine containers. Initially they all fed and behaved normally. After approximately 2 weeks, the larger one appeared to have lost weight. Certainly not something that triggered any alarms for a newly arrived animal, perhaps just a stress related anomaly. Well, I got rather busy over the following 2 weeks and hadn’t remembered to pay any particular attention to the large one. So when I did take a special look, I was startled at what I saw. The Crested had gone from robust to emaciated within a span of 3-4 weeks. At that time he was obviously near death, and by the next morning he was in fact dead. The 3 other geckos that came from the same source were still doing fine and continuing to gain weight.

That afternoon I was determined to find out what had happened to this animal. So I performed a comprehensive necropsy. I’ve spoken with several Rhac breeders and after they shared their stores with me, I shared mine with them. Now I’m sharing this with you in the hopes that you can identify potential trouble early and save the ailing gecko. Here’s the results:

This is the Crested as it appeared on the morning it passed. In this image you can see a very thin gecko with a bloody and congested intestine. As well as what appears to be 30% of its liver in a state of necrosis (later confirmed on histological exam of the tissue).

Here you can see a focal area of ulceration, a product of ulcerative colitis.

I performed a wet-mount of the intestinal contents. What I found was a lot of blood (RBC’s) and a few protozoan parasites. Those are likely to be non-pathogenic organisms (probably Trichomonas spp) that inhabit their intestine, but still interesting.

Here you can see a cross section of the ulcerated area of the intestine. It shows a lot of blood and a loss of mucosal surface (epithelium).

Now we get to the interesting part. This is a photomicrograph of the sloughed tissue and other material in the intestinal lumen (middle area). What I found were ameba like structures that later presumptively identified by an infectious disease specialist as Entamoeba invadins.

Here is the same organism in the liver, 30% of which was necrotic (dead).

This particular organism appears to devastate the normally very disease resistant Crested Gecko (but doesn’t appear to have the same affect on other Rhac spp. based on lack of reports of affected gecko). Other breeders have relayed to me similar circumstances where Crested have died, so this organism is within the captive community.

Signs & Symptoms
• Rapid weight loss
• Lethargy
• Swollen Vent (late stage)
• This is contagious though contact with the feces of ailing geckos

Treatment
• Highly susceptible to Flagyl (Metronidazole)
• 250mg/kg for 3 treatments is probably enough
• You must keep the cage clean and bleached during treatment to prevent re-infection.
• You should also treat all other geckos that have had any contact with the affected one. Treating the entire colony (could easily done by medicating their food) may be needed as a precaution if food/water dishes and cages are moved from cage to cage.

Take home message: If noticed early on, this is an easy and highly treatable disease!!!

There are other causes of weight loss (like intestinal blockage), but amebiasis should be part of the treatment plan straight away - if you want the best chance to save your ailing gecko.

Feel free to comment and thanks for the long read (JFYI - I'm a research scientist by profession),

-Randy May
www.neoscales.com

As you know, your findings and the help of another friend of ours helped me to save several valuable geckos from a group that I purchased (from a different source) recently as well. The flagyl treatment seemed to knock the disease out in a matter of days. The geckos, which were further quarantined (moved to another facility) seem to be doing well and will likely be coming back home soon.

The fact that these infected geckos are coming from various sources makes me wonder if "Entamoeba invadins" may be coming from other reptile species who are not (or not as) susceptible to it. Any thoughts on this?

-Anthony Caponetto
//ACReptiles.com

As you know, I had a similar experience with some acquired ciliatus about a year and a half ago. Very similar symptoms..... gecko's don't crash quickly, just slowly get thin and lethargic. Very similar to the way a leopard gecko that suffers from "crypto" ... my first thought was that it could also be "crypto" ..... a really bad thing that can wipe out entire colonies of geckos and is nearly impossible to eradicate.

I immediately sent two specimens to Dr Scott Stahl DVM, who, after extensive pathology, found that it was what appears to be the same pathogen that you describe. I was quite relieved to find the results were not crypto, and instead, an amoeba. Not that any pathogen is good, but as far as ease of eradication, it was an easy treatment. I used a 150mg/kg regiment every other day for five treatments, and the geckos quickly recovered and were back to normal health in a matter of weeks.
Crested geckos have proven to be one of the most disease resistant species of commonly kept reptile. To my knowledge, and from many conversations, there has not been a case of cryptosporidia found in crested geckos.

For some reason, they do appear sensitive to this amoeba, and considering the hardiness of cresteds in general, and their resistance to most pathogens, Amoebiasis should be considered a prime suspect in the case of any weight loss or lethargy in a crested gecko.

This amoeba can have the same effect on other reptiles such as leopard geckos and bearded dragons, It has also been found in tortoises. Cross contamination from exposure to other species is most likely the source of infestation. Other species may carry the pathogen without showing symptoms, but crested geckos for some reason show little resistance once infected.

Excellent presentation Randy! Your understanding of the problem and your ability to use photo's to educate people is amazing. I am sure that through your hard work and ability to present your findings in a clear and simple manner, that many cresteds in the future will benefit from your post. If we ever print a Second Edition of the Rhacodactylus book, I would love to print your post, with photo's, just the way you presented it here. Let me know if you wouldn't mind...

Allen Repashy