Juvenile Cellulitis
Juvenile cellulitis, also called juvenile pyoderma, puppy strangles, juvenile sterile granulomatous dermatitis and lymphadenitis) is an uncommon disorder of the face, pinnae, and submandibular lymph nodes, usually in puppies. The condition is presumed to be immune-mediated based on histopathological features and response to immunosuppressive forms of therapy.
A heritable nature has been suggested. Dachshunds, Golden Retrievers, yellow Labrador Retrievers, Gordon Setters, Lhasa Apsos, and Pointers are most commonly affected, but any other breed can have this disease. Most affected animals are less than 4 months old, but occasionally the disorder is reported in adults. Several puppies or only one in the litter may be affected. Signs are characterized by vesicles or pustules in the inner surface of the outer ear, on the muzzle, lips, and eyelids which rapidly progresses to extensive facial swelling, abscesses and draining lesions.
Occasionally lymph nodes will abscess and drain. A few cases will develop nodules over the trunk, penis and anus areas due to a panniculitis. Puppies usually have fever, are depressed and lose appetite. Permanent areas of alopecia and scarring may result if the lesions are extensive.
Diagnosis is based on history, clinical signs, cytologic examination of draining inflammatory fluid, skin biopsy, and response to therapy. Skin scrapings are performed to rule outdemodicosis. Bacterial cultures sometimes reveal organisms, although they are secondary infection. Although juvenile cellulitis has many clinical similarities to pyoderma, it responds to corticosteroid therapy. Antibiotics are used to treat secondary infection. Treatment with bactericidal antibiotics (cephalexin, cephadroxil) and immunosuppressive doses of corticosteroids (prednisolone) is required for several weeks. Once lesions have resolved, the dose is slowly reduced to an alternate day schedule to prevent relapses. The condition usually resolves completely, with little chance of recurrence. Owners should be prepared for scarring which may be permanent.
Complement System
Complements are a group of blood serum proteins that are critically important in the defense against infection. The complement system includes at least 30 proteins.
The first nine of these proteins were given numbers as their names, such as C1, C2, C3, etc. As more proteins were discovered, they were named with letters, such as Factor B and Factor D. Still, others were given more descriptive names such as C1 Inhibitor. These proteins act together to provide critical help in the defense against infection in a number of ways. One of the proteins, C3, acts to coat bacteria so that the bacteria are more easily ingested by white blood cells.
Others, C7, C8 and C9, assemble on the surface of a certain kind of bacteria and punch holes in their walls, causing them to rupture and die. Finally, small fragments of two of the complement proteins, C3 and C5, can cause an increase in blood supply and attract white blood cells to areas of infection, both of which are needed to clear an infection. Deficiencies in one or several complements may cause serious problems, but at this time, it is not possible to replace the missing components of the complement system.
In general, complements have rapid turnover and often must be made by the body on a daily basis. Therefore, long-term replacement therapy is not an option since injections of highly purified components would be required almost every day and the proteins are difficult to purify.
Patients with abnormalities that are associated with a high frequency of infection are usually helped by immunization when available and, occasionally, are treated with prophylactic antibiotics. Most patients with complement deficiencies can expect to become productive adults, if they are recognized as having the deficiency and treated early and vigorously.
