Page 1532 - Small Animal Internal Medicine, 6th Edition

1504 PART XIV Infectious Diseases

lavage is more sensitive than transtracheal aspiration for In that study, 71% of the dogs with clinical relapse were
organism demonstration; organisms can also be found in positive for Blastomyces antigen in urine. Blastomyces derma-
VetBooks.ir samples obtained by percutaneous lung aspirates. However, titidis DNA can also be amplified from cerebrospinal fluid
(CSF) of dogs with neurologic disease (Han et al., 2015).
in one study, B. dermatitidis was identified in 13 of 17 dogs
after transtracheal aspiration (McMillan and Taylor, 2008).
Growth in culture requires 10 to 14 days and is of lower yield Treatment
than cytology or biopsy. Amphotericin B, ketoconazole, both amphotericin B and
A Blastomyces antigen assay is available for human ketoconazole, and itraconazole alone are used most fre-
samples and has been evaluated in small numbers of dogs quently for the treatment of blastomycosis in dogs (Table
(MVista Blastomyces Antigen EIA; www.miravistalabs.com). 97.2). Amphotericin B is generally used in animals with life-
The assay is sensitive but not specific for B. dermatitidis. In threatening disease; the lipid or liposomal encapsulated
a study of 46 dogs with confirmed blastomycosis, the sensi- product is less likely to cause toxicity. If regular amphotericin
tivities of the antigen test using urine or serum were 93.5% B is used, the animal should be well hydrated with 0.9%
and 87.0%, respectively (Spector et al., 2008). In contrast, the sodium chloride before treatment, and treatment should be
sensitivity of serum antibody results by AGID was 17.4%. In discontinued if the patient becomes azotemic. Because itra-
another study, Blastomyces antigen was detected in urine of conazole is as effective as amphotericin B and ketoconazole
all 21 dogs tested as well as in 18 of 20 sera (Foy et al., 2014). alone or in combination and has fewer adverse effects, it has

TABLE 97.2
Antifungal Drugs Used in the Management of the Systemic Canine and Feline Fungal Diseases

DRUG SPECIES DOSAGE ORGANISM
Amphotericin B D 1 mg/kg, IV, up to 3 times weekly to a cumulative dose of Bl, H, Cr, Co
a
deoxycholate 4-8 mg/kg.
0.5-0.8 mg/kg SC 2-3 times weekly to a cumulative dose of
4-8 mg/kg. b
c
C 0.25 mg/kg IV up to 3 times weekly, to a cumulative dose of Bl, H, Cr, Co
4-6 mg/kg
0.5-0.8 mg/kg SC 2-3 times weekly to a cumulative dose of
b
4-6 mg/kg
Amphotericin B D 2-3 mg/kg, IV, 3 times weekly to a cumulative dose of Bl, H, Cr, Co
d
(lipid complex) 12-27 mg/kg
C 1 mg/kg IV infusion 3 times weekly to a cumulative dose of
12 mg/kg
Fluconazole D 5-10 mg/kg PO or IV q12-24h Bl, H, Cr, Co
C 25 or 50 mg/cat PO q12-24h Cr, Bl, H, Co
Flucytosine e C 50 mg/kg PO q6-8h Cr
Ketoconazole D 10 mg/kg PO q12-24h Bl, H, Cr, Co, Sp
C 5-10 mg/kg, PO, q24h Bl, H, Cr, Co, Sp
Itraconazole D 5-10 mg/kg, PO, q12-24h Bl, Cr, H, Co, Sp
C 50-100 mg/cat/day PO Bl, Cr, H, Co, Sp
Posaconazole C 30 mg/kg, PO loading dose followed by 15 mg/kg, PO, q48h Bl, Cr, H, Co, Sp
Terbinafine D 30-35 mg/kg, PO, q24h Cr, Bl, H, Co
Voriconazole f D 4 mg/kg, PO, q12h Bl, Cr, H, Co

a In dogs with normal renal function, dilute in 60-120 mL 5% dextrose and administer IV over 15 minutes; in dogs with renal insufficiency but
with a blood urea nitrogen level <50 mg/dL, dilute in 500 mL to 1 L 5% dextrose and administer IV over 3-6 hours.
b Mix in 400 mL (cats) or 500 mL (dogs) of 0.45% saline and 2.5% dextrose solution, and administer SQ.
c In cats with normal renal function, dilute in 50-100 mL 5% dextrose and administer IV over 3-6 hours.
d Dilute the contents of a vial with 5% dextrose to a final concentration of 1 mg/mL and shake for 30 seconds. Draw up needed volume and
filter through an 18-gauge Monoject filter needle into 100 mL of 5% dextrose. Infuse intravenously over 15 minutes.
e Should be used in combination with amphotericin B.
f Has been used in cats as well, but is associated with neurotoxicity (Quimby et al., 2010).
B, Dog and cat; Bl, Blastomyces; C, cat; Co, Coccidioides; Cr, Cryptococcus; D, dog; H, Histoplasma; IV, intravenous; PO, oral;
SC, subcutaneously; Sp, Sporothrix.