Multimodal Therapies Including Allogenic Stem Cells for Treatment of Keratopathies in California Sea Lion (Zalophus californianus) Pups
Keratopathies are reported in managed and wild California sea lions and have been treated by multiple methodologies.1-7 Over the course of one month, four California sea lion (Zalophus californianus) pups presented with varying severities of ocular keratopathies. Three animals developed bullous keratopathies and one animal developed bilateral severe diffuse corneal edema. Despite conducting multiple diagnostics to determine the etiology, the cause of this cluster of keratopathies remains unknown. Differential diagnoses included otariid keratopathy, trauma, infection (bacterial, viral, fungal), and immune mediated.
Oral antibiotics, analgesic and anti-inflammatory medications were used initially. Due to minimal response to therapy, thorough exams of the anterior segments of the eyes were completed under general anesthesia. Dexmedetomidine was used to decrease ventral deviation of the cornea under anesthesia. Treatment modalities used directly on the eye while under anesthesia included topical and subconjunctival allogenic stem cells, as well as subconjunctival platelet rich plasma. Once animals were conditioned to receive topical eye medications, antimicrobials, anti-inflammatories, and immune modulators were added to the treatment protocol.
In the case of the severe diffuse corneal edema, significant peripheral corneal clearing was seen within two days of the initial subconjunctival stem cell injection. In all cases, keratopathy improvement was seen following stem cell and/or PRP injection. The use of multiple modalities, especially the stem cell and PRP injections, improved recovery time and limited corneal scarring in these cases. For significant keratopathies, multimodal therapies should be considered as a viable option when managing corneal disease in young pinnipeds.
The authors would like to thank our colleagues at the Navy Marine Mammal Program and the National Marine Mammal Foundation. Special thanks to the U.S. Army Veterinary Corp for their dedicated service and support; Risa Daniels, Celeste Parry, Chris Hammell and Kevin Carlin for their help with diagnostic sampling and data collection; and Dr. Stephanie Venn-Watson and Dr. Sam Ridgway for expertise and guidance.
* Presenting author
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