CHAPTER 30 LEISHMANIASIS: PROTOZOAN DERMATITIS 461
Dirofilariasis
Hepatozoonosis
Multiple myeloma
Metastatic neoplasia
Distemper virus
Systemic vasculitis. Cutaneous:
Systemic or cutaneous lupus erythematosus
Keratinization disorder
Idiopathic sebaceous adenitis
Demodicosis
Dermatophytosis
Bacterial pyoderma
Sterile pustular dermatoses (e.g., subcorneal or eosinophilic)
Vasculitis
Nutritional dermatoses (e.g., vitamin A responsive, zinc responsive)
Idiopathic nasodigital hyperkeratosis
Superficial necrolytic dermatitis
Cutaneous adverse drug reaction
Lichenoid-psoriasiform-like dermatosis
Reactive histiocytosis
Leproid granuloma
Pemphigus foliaceus
Epitheliotropic lymphoma
Sterile granulomatous/pyogranulomatous dermatitis
Lupoid onychodystrophy (symptoms isolated to claws).
DIAGNOSTICS
Diagnosis made by compatible clinical symptoms and positive serologic testing along
with confirmation of the presence of organisms in sampled tissues by immunohisto-
chemistry or polymerase chain reaction (especially lymph node and skin; bone mar-
row should be sampled if other sites fail to demonstrate organisms).Asymptomatic leishmanial dogs my exhibit symptoms due to coinfections and not
Leishmania, leading to treatment failures from inappropriately directed therapy.
CBC/biochemistries: thrombocytopenia, lymphocytosis, nonregenerative anemia;
hyperproteinemia with hyperglobulinemia and hypoalbuminemia; elevated liver
enzymes; azotemia; hyperamylasemia; elevated creatinine phosphokinase.Anemia and thrombocytopenia are partly produced by the high number of amastig-
otes in bone marrow.
Parasite numbers in blood smears are typically low.
Urinalysis: proteinuria.
Coombs, ANA, LE cell tests: rare positive.
Intradermal leishmanin injection (Montenegro test): positive skin reaction.