Neonatal and Pediatric Health
Some of the neonatal and pediatric conditions currently being monitored by the Neonatal and Pediatric Committee.
Eye conditions associated with this syndrome are best diagnosed by a veterinary ophthalmologist, which can be done as early as eight weeks of age. Reported eye conditions include:
If you suspect a pup in your litter to have this syndrome, please contact the chair of this committee. Researchers need more information in order to sort this out. Consider necropsy (autopsy or post mortem examination) on any suspicious puppy death and get early veterinary evaluations of puppies that do not appear to be thriving. It is also highly recommended to have board certified veterinary ophthalmology evaluations of litters before placing puppies in their new homes as some inherited eye diseases, including puppy eye syndrome, can be detected at early ages.
Lymphedema is an abnormal accumulation of lymph which is derived from the fluid between the cells of the body. Puppies severely affected with this condition have also been described as “walrus puppies,” “water puppies,” or anasarca, which is a term used to describe severe, generalized edema. More mild cases typically involve one or more legs, most commonly the hind legs. The swelling starts near the toes and moves towards the body. When depressing the skin with your finger it will cause an indentation that will remain for some time after the release of the pressure (pitting edema). In severe cases, swelling is generalized over the entire body (anasarca), a form that is often fatal shortly after birth and a condition that commonly result in a need for an emergency C-section due to difficult in passing through the birth canal.
Lymphedema has been reported in the scientific literature to occur in a variety of species including humans, horses, pigs, cows, cats, and dogs, with a variety of breeds reported such as Bulldogs, Poodles, and Labrador Retrievers. In other species, this has also been referred to as “hydrops”.
The diagnosis of primary congenital lymphedema is based on clinical signs and veterinary evaluation. The diagnosis is often made based on characteristic clinical signs and presentation. Skin biopsies can assist with confirmation of the excessive fluid accumulation; however, the anomaly in the lymphatic system cannot be identified with a skin biopsy alone. Diagnostic tools to further evaluate the lymphatic system such as contrast lymphangiography have been performed in a small numbers of dogs with lymphedema but are not readily available. Lymphoscintigraphy, magnetic resonance imaging (MRI), computerized tomography (CT), and doppler ultrasound are also additional diagnostics that have been reported to evaluate the lymphatic system of patients with lymphedema, however, these are most commonly utilized in humans rather that veterinary patients with this disorder.
Primary lymphedema was noted to occur in a family of Poodles and was studied by researchers at the University of Pennsylvania in the 1960s. In that study, primary lymphedema was reported to be inherited as an autosomal dominant disease with variable expressivity (incomplete penetrance) in that family of Poodles. The disorder has been reported in the veterinary literature to be an inherited disease in a variety of dog breeds with suspected autosomal dominant with incomplete penetrance as well as autosomal recessive modes of inheritance. However, in most other dog breeds where this disorder has been described, the exact mode of inheritance has not been thoroughly evaluated. Several candidate genes have been identified in humans as well as other species where inherited primary lymphedema has been described; however, there are no current ongoing research projects involving this condition in dogs.
The difficulty with lymphedema in the dog is that there can be variable expression of the disorder in affected animals in both the severity of clinical signs as well as the age of onset, so that some affected dogs may be easily be overlooked. In some cases, signs of edema may be so mild and improve with age that a puppy is not noticed to be affected with the condition and may unknowingly enter a breeding program. It is important for Portuguese Water Dog breeders and owners to be informed about this disorder. Any puppy or adult Portuguese Water Dog that is suspected to be affected with lymphedema should be evaluated by a veterinarian familiar with this disease in an effort to appropriately identify affected animals. Additional examination of relatives of suspected affected animals is also important to better characterize this disease so that care can be taken to avoid perpetuation of the inherited form of this disorder in the gene pool.
PWD owners and breeders who have a dog diagnosed with lymphedema (or relative) are encouraged to contact the PWD Pediatric and Neonatal Health Committee as well as consider submission of DNA to the Canine Health Information Center’s DNA Repository (www.caninehealthinfo.org/dnabank.html) for potential use in future research.
Why PWDCA is addressing this:
Both Puppy Eye Syndrome and Lymphedema affect the lifespan and quality of life of Portuguese Water Dogs.
Please see the information about the importance of necropsies (post mortem examinations) on any lost neonatal or pediatric puppy and please contact the chair of this committee is you suspect a pup in your litter may be affected with a health condition.