SymmetricalLupoidOnychodystrophyNicoleAHeinrichDVMDACVDMcKeeverDermatologyClinics

www.mckeevervetderm.com952-946-0035

Symmetricallupoidonychodystrophy(SLO)isanautoimmunediseasecharacterizedbynailsthatbecomeinflamedatthebaseandeventuallyfalloff.Theconditioncanbeextremelypainful.SLOtypicallystartswithonenailbeingaffected.Allofthenailseventuallybecomeaffectedwithintheensuing1to3weeks.Thenailplateliftsawayfromthequickwithanappearancethatoftenlookslikeanopenhoodonacar.ThequicktendstobleedandmaybecomeinfectedwithStaphylococcus,E.coliorPseudomonas.Differentialdiagnosesinclude:nailtraumaornailbedneoplasia;however,thesediseasesonlyaffectoneortwonails.ThecharacteristicofmultiplenailsfallingoffispathognomonicforSLO.ThemostimportantfactorinthetreatmentofSLOistocontrolpain.NSAIDsandtramadolcombinedaretypicallyeffective.Dogsmusthaveareducedactivityleveluntilthediseaseiscontrolledsothatnailsarenotinadvertentlytraumatizedfurther.ThesecondfactorthatmustbeaddressedwithSLOistreatingandpreventinginfection.Cytologymustbeperformedoftheaffectedquickstodetermineifinfectionispresentornot.Ifthenailsareinfected,thensystemicantibioticistypicallyrequiredfor3or4weeks.Topicalearmedicationthatcontainbetamethasoneandgentamicincanbeappliedtoinfectedquicks2to3timesperdaytospeedhealing.Ifnoinfectionispresent,theneffortsshouldbefocusedonpreventinginfection.Dailychlorhexidineorsoapywaterpawsoakscanhelppreventinfectionwhilethenailsarehealing.Thefinalfactorthatmustbeaddressedistheunderlyingdiseaseitself.SLOisaconditionthatiscontrolled,butnotcured.Itrequirescontinuoustreatmenttopreventrelapses.TherapiesthattendtobemosteffectiveforSLOinclude:Atopica®ordoxycyclineandniacinamide.Atopica®isatherapythatissafeforlong-termuse,administeredoncedaily(andcansometimesbereducedtoeveryotherdaydosing),andtakes3to6weekstotakeeffect.Itcancausegastrointestinalupsetinsomepatients.ThesesignscanbeamelioratedbyadministeringtheAtopica®asafrozencapsuleandalsobygivingitwithfood.

Doxycycline/niacinamideisatherapythatisalsosafeforlong-termuse;although,rarelyhepatotoxicitycanoccur.Somedogsexperiencegastrointestinalupset.Doxycyclineisdosedat5-10mg/kgbymouthtwicedailyandniacinamideisdosedat500mgbymouthtwicedailyformediumandlargedogs.Niacinamideisgivenasahalfdosetwicedailyforsmalldogs.Thistherapymaytakeupto12weekstoreachmaximumeffect.Bloodworkshouldbemonitored.Omega3fattyacids(180mg/10lbbodyweight)givendailywithfoodperdayisahelpfuladjunctivetherapy.OnceSLOiscontrolled,flare-upsofthediseaseareuncommon.Medicationsshouldbereducedtothelowestdosethatpreventsthequicksfrombecominginflamed.DogsaffectedwithSLOtypicallyneverhavenormalnailsaftertheinitialinsult.Thenailstendtore-growinunusualshapes(sometimespointingupwards)andareoftenbrittle.