Feline Plasma Cell Pododermatitis Nicole A. Heinrich DVM DACVD

McKeever Dermatology Clinics www.mckeevervetderm.com 952-946-0035

Plasmascellpododermatitisisanuncommonimmune-mediateddiseaseaffectingthepawpadsofcats.Thepathogenesisisunknown,butmaybeahypersensitivityoranautoimmuneprocess.Itischaracterizedbydenseinfiltrationofplasmacellsintothepads.Theresultingclinicalsignsareswollenpawpads.Theswellingcanbesubtleinitiallyanddramaticinseverecases.Variablescaling,fissuringandevenerosioncanbepresentaswell.Thepadsmaydevelopapurplehueandthetoesmayspreadinanunusualmannerwhenthecatisbearingweight.Generally,thisisanon-pruriticcondition,althoughcatsmaylickthepawsduetodiscomfort.Concurrentstomatitishasbeenreported.Thediagnosisisoftenmadebasedonhistoryandphysicalexam.Askinbiopsyrevealsadiffuseinfiltrateofplasmacells.Serumchemistrymayrevealhypergammaglobulinemia.Themaindifferentialdiagnosesinclude:atopicdermatitis,foodallergyandpemphigusfoliaceus.Allergiestendtobemorepruriticthanplasmacellpododermatitis.Pemphigustendstobemorepainfulwiththickercrustsonthepads.Additionally,theclawfoldstendtoaccumulateacaseous,whitedebrisinpemphigus.Bothcondtionsusuallyfeatureinterdigitalerythemaasopposedtoplasmacellpododermatitiswheretheinterdigitalskinisrarelyaffected.Thisconditionisgenerallycontrolled,butnotcured.Catsrequireongoingmedicationtokeepthepawscomfortable.Treatmentsthataremostofteneffectiveinclude:doxycyclinesuspensionandmodifiedcyclosporine.Doxycyclineisadministeredatadoseof5mg/kgPOq12hoursfor6to8weeks,thenasneededtocontrolswelling.Oncedailydosingmaybepossible.Modifiedcyclosporine(Atopicaispreferable)isadministeredatadoseof5mg-7mg/kgPOq24hoursfor6to8weeks,thenasneededtocontrolswelling.Everyotherdaydosingmaybepossible.Theprognosisisgood.