I think uveitis is a symptom sometimes present with e. Cuniculi.
If you look at images of phagoclastic uveitis, is that similar to what you’re seeing in Links eye?

There is a blood titer test that can be done for E.C but it can give mixed results so sometimes vets opt not to do it. Did your vet do one?

It sounds like you’re in good hands with your vet. The eye can also heal remarkably quick.

I’ve literally just finished meds for EC with one of my rabbits. Her symptom was headtilt and the eye movements. She was also caught early and I’m happy to say she is doing great. It gets worrisome in the beginning but then they make improvements. So definitely hang on to that hope!

A couple of years ago, one of the rabbits at the Sanctuary where I volunteer developed E. cuniculi, and it affected her eye. The Sanctuary vet wrote this article for us to include in our newsletter.

Encephalitozoonosis in Rabbits

Dr. Cynthia K. Wheat, DVM

Encephalitozoonosis is a common disease of rabbits caused by Encephalitozoon cuniculi, a spore forming protozoan parasite. The spores are shed in the urine of an infected rabbit and may survive in the environment for 4 – 6 weeks. Infection occurs when a rabbit ingests urine contaminated food. The spores are absorbed from the intestines and are carried by the blood to other organs, including heart, liver, spleen, lungs, brain , kidneys and eyes. Infection usually occurs within the first 6 weeks after birth, either from the doe or from contact with other infected rabbits. Infection can also occur in utero, from the doe to the developing fetus. This type of infection most often targets the developing lens in the eye. Spores that target the kidneys cause a nephritis or inflammation of the kidneys. Infective spores appear in the urine about 4 – 6 weeks post infection, peak at about 2 months post infection and are no longer shed by 3 months post infection. The rabbit is not infectious to other rabbits once spores are no longer shed.

Infection is widespread in rabbits but most develop chronic, subclinical disease and never exhibit any signs of illness. After infection, antibodies develop which aids in limiting tissue damage and spore excretion. In rabbits with healthy immune systems, antibodies prevent multiplication of organisms but do not destroy the spores. An asymptomatic infected rabbit may develop symptoms of disease if the immune system becomes compromised by illness, stress, poor or inadequate diet, or age. Therefore, disease may occur many years after initial infection.

Although E. cuniculi can infect many organs, symptomatic rabbits most often develop signs of disease associated with the central nervous system (brains), kidneys or eyes. Kidney disease is rare. Symptoms include lethargy, depression, dehydration, gastrointestinal signs, loss of appetite and weight loss. Ocular infection can be seen in any age or breed of rabbit but is most often associated with dwarf breeds and young rabbits less than two years old. Usually, only one eye is affected. The classic lesion is phacoclastic uveitis–inflammation of the middle layer or interior of the eye secondary to lens rupture and release of lens material into the eye. Symptoms may include a white mass within the eye, a red eye, hypopyon (pus in the eye), sensitivity to light and cataract formation. Uveitis may lead to blindness and glaucoma or shrinking of the eye. About 75% of rabbits with cataracts and uveitis may test positive for E. cuniculi. E. cuniculi is often associated with neurologic disease. Symptoms include changes in behavior, head tilt, nystagmus (involuntary eye movement), ataxia (uncoordination), rolling, tremors, seizures, paresis (weakness) of rear legs or paralysis. Signs often occur following a stressful event.

Diagnosis of E. cuniculi is difficult. Several tests are available to check for the presence of antibodies. However, a positive test only indicates exposure to the disease, not infection. The test cannot distinguish between active infection, latent infection or if infection is no longer present. A presumptive diagnosis is based on clinical signs, the presence of high antibody titers, and the response to treatment. There is no correlation between titer numbers and the severity of disease or shedding of spores.

Treatment of ocular disease includes anti-parasitic drugs (sometimes long term) and phacofragmentation–use of an ultrasound to break up the cataract into smaller pieces, then removal of the pieces. This procedure should be performed by a veterinary ophthalmologist. If surgery is not an option, the rabbit should be treated with anti-parasitic drugs and non-steroidal anti-inflammatory medication. The eye should be treated with a topical corticosteroid. In order to save the eye, early and aggressive treatment is needed. Most eyes will atrophy (shrink). If glaucoma develops or the eye becomes painful, it should be removed. Medications slow the progress of disease but do not clear infection. There is no agreement on how to best treat neurologic manifestations of E. cuniculi. Disease may be associated more with inflammation caused by the organism than the protozoan itself. Treatment includes the use of anti-parasitic drugs (i.e. albendazole, oxibendazole, or fenbendazole) and nursing care of debilitated rabbits. Some veterinarians advocate the use of one dose of a short-acting corticosteroid to reduce inflammation. Long term nursing care with assisted feeding and fluids may be required. Some neurologic signs may persist and head tilt may be permanent. Effectiveness of treatment is difficult to assess since some rabbits will improve with no treatment.

Important Points to Remember
Most rabbits are infected at an early age.
Infective spores are shed in urine for about 3 months.
Spores are ingested, absorbed and carried in the blood to other parts of the body.
Many rabbits are infected but very few will develop disease.
Immunocompromised asymptomatic rabbits may develop clinical disease.
Neurologic signs can occur years after infection.
A positive test indicates exposure, not infection.
Effectiveness of treatment is hard to assess.

Good luck with your vet appointment. It sure sounds like he’s in good spirits during this illness!