Peer-reviewed veterinary case report
Laser treatment with methylene blue helps cats with stubborn skin
By Ramos, Mariana Lucy Mesquita et al.·Published in Photodiagnosis and photodynamic therapy·2026·Fundaç, Brazil·View original on PubMed →
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Original publication title: Adjunctive laser-based antimicrobial photodynamic therapy using methylene blue for refractory feline sporotrichosis.
- Species:
- cat
Plain-English summary
Two cats with stubborn skin lesions caused by a fungal infection called sporotrichosis were brought in for treatment after not responding well to standard medications. They had been on itraconazole and potassium iodide for a long time, but their symptoms only improved slightly. To help them heal completely, the veterinarian added a new treatment called antimicrobial photodynamic therapy (aPDT), which involved several sessions using a special dye. After 10 to 11 sessions, both cats were completely cured, showing that this new therapy can be very effective for tough cases of sporotrichosis.
People also search for: cat skin infection treatment · sporotrichosis in cats · feline antifungal therapy · laser treatment for cat skin problems
Abstract
Feline sporotrichosis, a potentially zoonotic fungal infection caused by Sporothrix spp., represents a therapeutic challenge, especially in refractory cases. This report describes two cases that presented with refractory cutaneous lesions to conventional systemic treatment. Both cats were initially treated with a combination of itraconazole and potassium iodide for a prolonged period, resulting only in partial improvement and persistence of cutaneous lesions. Due to the lack of complete response, antimicrobial photodynamic therapy (aPDT) was introduced as an adjuvant treatment. The protocol involved multiple sessions of aPDT using methylene blue as photosensitizer, while conventional therapy was maintained. The first cat achieved complete clinical cure after 11 sessions and the second after 10 sessions. The successful outcome in these cases demonstrates the potential of aPDT as a promising adjuvant technique in the treatment of refractory feline sporotrichosis.
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Search related cases →Original publication on PubMed: https://pubmed.ncbi.nlm.nih.gov/41352548/