Leopard Gecko Proliferative Enteritis: A Serious Cryptosporidium-Linked Intestinal Disease

Leopard gecko proliferative enteritis is a serious intestinal disease most often associated with Cryptosporidium infection, especially in geckos with chronic weight loss and the classic "stick tail" appearance. In leopard geckos, the parasite tends to affect the small intestine, where it can trigger thickening of the intestinal lining and long-term inflammation. That makes it harder for the gecko to absorb nutrients, even if it is still trying to eat.

This condition is especially concerning because it often develops gradually. A gecko may seem mildly off at first, then lose tail fat, become weak, pass abnormal stool, or stop eating. By the time signs are obvious, the disease may already be advanced.

Cryptosporidium infections in reptiles are difficult to eliminate completely. That means the goal is often not a cure, but a realistic care plan that supports comfort, limits spread to other reptiles, and helps your vet assess prognosis over time. Early evaluation matters because other problems, including pinworms, coccidia, bacterial enteritis, impaction, husbandry errors, and tumors, can look similar.

The main cause is infection with Cryptosporidium, a microscopic protozoal parasite spread through contaminated feces, regurgitated material, surfaces, feeders, water dishes, and shared equipment. Infected reptiles shed hardy oocysts into the environment. Once another gecko swallows those oocysts, the parasite can infect the intestinal lining and continue the cycle.

Leopard geckos are especially known for developing an intestinal form of cryptosporidiosis associated with chronic wasting. In practical terms, that means a gecko may become infected after contact with a new reptile, a contaminated enclosure, used decor that was not disinfected well, or poor quarantine practices.

Stress and husbandry problems do not directly cause Cryptosporidium, but they can make a sick gecko less resilient. Inadequate temperatures, poor sanitation, overcrowding, and delayed veterinary care may worsen weight loss and recovery potential. Your vet will also consider other causes of chronic GI disease, because not every thin gecko with diarrhea has cryptosporidiosis.

Diagnosis usually starts with a careful history, physical exam, weight trend, and review of husbandry. Your vet may feel abnormal thickening in the gastrointestinal tract, especially in more advanced cases. Because reptiles can shed parasites intermittently, one negative stool test does not rule Cryptosporidium out.

Common tests include fecal examination, acid-fast staining, and PCR testing on feces. PCR can help detect Cryptosporidium DNA, while microscopy may identify oocysts if enough are being shed. Repeated samples are often more useful than a single sample.

Your vet may also recommend radiographs, ultrasound if available, and bloodwork when feasible to look for dehydration, organ stress, or other disease. In some cases, endoscopy or biopsy may be discussed, especially if the diagnosis is unclear or another intestinal disorder is possible. Definitive confirmation may still require histopathology, and in some cases the diagnosis is only fully confirmed after necropsy.

Prevention centers on quarantine, sanitation, and careful sourcing. Any new leopard gecko should be housed separately from established reptiles, ideally with separate feeding tools, hides, and cleaning supplies. A quarantine period of at least 60-90 days is a practical minimum, and longer may be wise if there are any digestive signs or unexplained weight changes.

Use easy-to-clean surfaces during quarantine, such as paper substrate, and monitor body weight regularly. Prompt fecal testing is helpful for any gecko with poor appetite, loose stool, regurgitation, or tail thinning. Avoid sharing decor, water bowls, feeder bins, or handling equipment between reptiles unless they have been thoroughly cleaned and disinfected.

Good husbandry supports the immune system and makes illness easier to spot early. Leopard geckos do best with an appropriate temperature range, low ambient humidity with access to a humid hide, clean water, and a clean enclosure. If one gecko is suspected or confirmed to have cryptosporidiosis, talk with your vet about long-term isolation, environmental cleaning limits, and whether porous items should be discarded rather than reused.