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Cutaneous protothecosis: A case report

Bryan Edgar K. Guevara, Yu-Chen Chen, Johanna O. Flordelis, Chao-Kai Hsu, Julia Yu-Yun Lee



Cutaneous protothecosis usually presents as pyoderma-like lesions or infiltrating papules and plaques on the extensor side of the extremities. It can be misdiagnosed as eczema, pyoderma, or a fungal infection. Although it has been isolated from a swimming pool, sewers and rivers in the Philippines, there has been no reported case of cutaneous protothecosis in the country.



A 78-year-old Taiwanese male farmer visited the dermatology clinic due to a six-month history of a large, pruritic erythematous plaque studded with papulopustules on his left forearm. A potassium hydroxide (KOH) examination showed negative for hyphae or spores. And a skin biopsy showed morula-like bodies, which were highlighted by the Periodic acid-Schiff stain.



We report a case of cutaneous protothecosis from Taiwan so Filipino dermatologists will be aware of the clinical and histopathologic manifestations and management of cutaneous protothecosis.


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Cutaneous protothecosis: A case report