“Puppy strangles” sounds like a terrible disease. Its proper name, juvenile cellulitis, makes it seem a bit less scary. And it should. While the condition is something that only puppies normally get, it is curable, and, depending on the disease’s progression at time of treatment, a puppy can even recover from the immune-mediated pustular disorder without any long-term ill effects.
Although it can strike young dogs up to 4 months old, Autumn Davidson, D.V.M., M.S, an internal medicine specialist at the University of California, Davis William R. Pritchard Veterinary Medical Teaching Hospital, says it most commonly develops at 3 to 4 weeks, and up to 8 weeks of age, while the pups are still in the whelping box. Occasional cases are seen in dogs up to 4 years old.
Davidson also practices at PetCare Veterinary Hospital in Santa Rosa, Calif., where the staff sees about six cases a year. Because Davidson tends to see only severe cases or those in very young puppies at the teaching hospital, that caseload isn’t indicative of the prevalence of the disease across the nation, she says. Some credible information on juvenile cellulitis, including the Merck Veterinary Manual, says it is uncommon. But Davidson does not agree. She should know – she did a presentation on a case at the North American Veterinary Conference a few years ago.
The disease’s first sign is a yellow mucous discharge from the eyes, the sheath that covers the penis – the prepuce – or the vulva, the most external part of the female reproductive system. This symptom is soon followed by enlarged lymph nodes on either or both sides of the neck and under the jaw, Davidson says. The nodes are “often painful,” she said in her presentation.
Fortunately, she says, most breeders recognize that a yellow discharge in young pups is not normal, and most general practice veterinarians know the signs of juvenile cellulitis and can quickly diagnose and treat it. With aggressive corticosteroid treatment, most puppies will begin to recover within just a few days.
If the breeder or new owner of an older puppy doesn’t recognize the potential for danger in mucous or swollen, painful lymph nodes, pustules will begin to form on the puppy’s pinnae – the insides of the long part of the ear – on the muzzle, lips, eyelids, prepuce, vulva or anus. With just a modicum of common sense, it should be clear that just one, let alone more, of these pus-filled, inflamed, blister-like lesions demands an immediate trip to the veterinary clinic.
Some puppies will have a fever or, if of walking age, lameness after a week or two due to the inflammatory reaction going on throughout their bodies, or anorexia. These signs are not, however, common or key signs of juvenile cellulitis, Davidson says.
Appropriate treatment can almost always get the progressive disease under control, although for such young puppies some veterinarians hesitate to prescribe the needed dose of prednisone or prednisolone that can knock down the inflammatory response. Davidson prefers to treat with 2 mg per kilogram of weight once a day, along with twice daily, 30 mg/kg griseofulvin, another immune-modulating drug, which helps “quiet down” the immune system. The addition of griseofulvin allows the veterinarian to taper off on the corticosteroid or eliminate it completely as soon as there’s some positive response. Some puppies will need antibiotics for any skin infections that may have developed after pustules burst, then scab.
Juvenile cellulitis is believed to be immune-mediated, meaning created by a malfunction of the immune system, however it is not a case of poor or unsanitary care on the part of the breeder or new owner. “We see it in certain breeds and certain lines of dogs,” Davidson says, so current thought is that it has a genetic cause. “Labrador Retrievers are probably the most common breed I see it in,” she says. Merck states that Golden Retrievers, Gordon Setters and Dachshunds are also susceptible, though Davidson was hesitant to name any other breed than the Lab. Unfortunately, at this time, there’s no funding for identifying the gene, whether dominant or recessive, that might pass on juvenile cellulitis, she adds, so no one is currently searching for it, to the best of her knowledge.
If pustules develop before treatment begins, a breeder who examines her puppies each day from birth on likely will find one or more pustules on a single area of the dog before they develop elsewhere. Otherwise, they may appear on the chin, paws, abdomen and chest. In addition, the lymph nodes can erupt as large, inflamed boils, which then burst, drain and crust up.
A puppy should not be vaccinated if it has signs of juvenile cellulitis or during treatment for the disease.
How long the pustules will continue to develop and remain is quite variable, Davidson says. It depends on whether treatment begins with a corticosteroid at a large enough dose to halt the out-of-control white blood cell activity. “If it’s caught early and treated aggressively, they should clear in a week,” she says. “If not, they can persist and progress. If they get to the point where they’ve got open, draining sores and large, abscessed lymph nodes, it can take weeks or months to get the disease under control. The longer it goes uncontrolled, the more chance there is for permanent scarring.” However, only a small percentage of the puppies Davidson has treated ended up with scars because she usually sees them “pretty early. But in most cases, 10 to 50 percent end up with scars.” The same goes for hair loss on and around the site of the pustules and abscessed lymph nodes. “It depends on the level of scarring,” she says. “If scarring is severe, the hair loss will be permanent.”
Regardless of the severity of the case and the amount of scarring or hair loss, if a dog is treated effectively, “we don’t usually see a relapse,” Davidson says.
One of the interesting aspects of this disease is that the pus that fills the pustules is sterile. In other words, it contains no bacteria, virus or other agent that would cause such a skin reaction.
The predominant inflammatory cell that triggers the pustule development is an epithelioid macrophage, a cell that “goes in and cleans up a mess,” Davidson says. In the case of the Lab she wrote about for her NAVC presentation, she describes taking skin samples from the puppy under local anesthesia, evaluating them and identifying “severe, chronic, multifocal coalescing pyogranulomatous panniculitis with fibrosis,” “diffuse hyperplasia” (enlargement of lymphoid tissue), and “mild acute focal periadnexal dermatitis,” “a severe inflammation in the skin and hair roots with multiple types of inflammatory cells.” She calls it a “very robust inflammation.”
Despite this puppy’s advanced case and his lack of response to initial treatment, he did recover, though he bears the scars of his ordeal on his hairless muzzle.
So, check those puppies daily. If you see yellow mucous discharge and feel enlarged lymph nodes, don’t waste any time getting a veterinarian’s diagnosis.