Erysipeloid is an occupational infection of the skin caused by traumatic penetration of Erysipelothrix rhusiopathiae. The disease is characterized clinically by an erythematous oedema, with well-defined and raised borders, usually localized to the back of one hand and/or fingers. Vesicular, bullous and erosive lesions may also be present. The lesion may be asymptomatic or accompanied by mild pruritus, pain and fever. In addition to cutaneous infection, E. rhusiopathiae can cause endocarditis, which may be acute or subacute. Endocarditis is rare and has a male predilection. It usually occurs in previously damaged valves, predominantly the aortic valve. Endocarditis does not occur in patients with valvular prostheses and is not associated with intravenous drug misuse. Diagnosis of localized erysipeloid is based on the patient's history (occupation, previous traumatic contact with infected animals or their meat) and clinical picture (typical skin lesions, lack of severe systemic features, slight laboratory abnormalities and rapid remission after treatment with penicillin or cephalosporin).

Bowen's disease (BD) is a form of intraepidermal squamous cell carcinoma, which is clinically characterized by gradually enlarging, well-demarcated erythematous plaques with irregular borders and surface crusting or scaling, affecting primarily the elderly. BD often presents with lesions difficult to treat with standard therapy as surgery, cryosurgery, or 5-fluorouracil (5-FU) for the risk of significantly poor cosmetic outcome, failure rate, and adverse events, related mainly to the age of the patients. Topical PDT with methyl aminolevulinate (MAL) represents a valid and approved therapy for BD lesions in many cases, especially for lesions located at poor healing sites or for large patches of disease, due to its high efficacy coupled with good tolerability and tissue-sparing attitude. In this study, we sought to investigate the efficacy, safety, and cosmetic outcome of MAL-PDT in a series of patients with BD lesions which were challenging to treat for clinical, surgical, and patient-related reasons, such as size of the lesion, difficult surgical approach for anatomical sites, or age of patients and request of the best cosmetic result. We also performed a long-term follow-up to assess recurrence rates and eventual late-onset adverse events.