A Randomized Clinical Trial Comparing Itraconazole and a Combination Therapy with Itraconazole and Potassium Iodide for the Treatment of Feline Sporotrichosis

Abstract

Feline sporotrichosis is an endemic disease with high occurrence in Brazil. Itraconazole (ITZ) remains the drug of choice for treating this disease in cats, despite the increasing reports of therapeutic failure. A controlled, randomized clinical trial was performed on 166 naive cats with sporotrichosis to assess the effectiveness and safety of the combination therapy with ITZ and potassium iodide (KI) compared with ITZ monotherapy. Cats were randomly allocated into two treatment groups: G1—ITZ 100 mg/cat/day—and G2—ITZ 100 mg/cat/day + KI 2.5–20 mg/kg/day. Cats treated in G2 presented 77% more risk of reaching a clinical cure (a positive effect) than those treated in G1, even when controlled by negative predictors. The survival curves of the two treatment protocols indicate that a clinical cure was achieved faster in G2. An increase in the KI dose was necessary in 28 cats due to the persistence of clinical signs. Adverse reactions were equally frequent in both groups and manageable with a temporary drug suspension and/or a hepatoprotective therapy. The combination therapy was associated with a higher cure rate and a shorter treatment time, suggesting that ITZ+KI arises as a better option for treating feline sporotrichosis and should be considered the first-line treatment, especially in the presence of negative predictors.

Neutrophil Oxidative Burst Profile Is Related to a Satisfactory Response to Itraconazole and Clinical Cure in Feline Sporotrichosis

“…Our results also endorse the use of the combination therapy with ITZ and KI as an excellent alternative for the treatment of feline sporotrichosis, as previously presented [ 3 , 4 , 58 , 59 , 60 ]. Although the combination therapy led to significantly increased cure rates of feline sporotrichosis in this study, it was not enough to successfully treat cats with progressive disease.…”

“…As previously mentioned, cats enrolled in the study were randomly submitted to one of the following two therapeutic regimens: Combination therapy: Oral administration of KI capsules (compounded medication), a dose of 2.5–10.0 mg/Kg/day, and ITZ capsules 100 mg (Prati-Donaduzzi ® , Toledo, PR, Brazil), a dose of 100 mg/day [ 3 ]. Monotherapy: Oral administration of ITZ capsules 100 mg (Prati-Donaduzzi ® , Toledo, PA, Brazil), 100 mg/day.…”

“…Combination therapy: Oral administration of KI capsules (compounded medication), a dose of 2.5–10.0 mg/Kg/day, and ITZ capsules 100 mg (Prati-Donaduzzi ® , Toledo, PR, Brazil), a dose of 100 mg/day [ 3 ].…”

“…However, disease progression, persistence and recurrence of clinical signs are still described in cats treated under this regimen, especially when there is nasal mucosa involvement or respiratory signs. In these cases, the use of the combination therapy of ITZ and potassium iodide (KI) has resulted in increased cure rates [ 3 ] and is the protocol recommended by the Brazilian guideline for the management of feline sporotrichosis [ 4 ].…”