Chronic ulcer in a patient with essential thrombocythemia taking hydroxyurea.

Chronic skin ulcers in patients with suspected pyoderma gangrenosum can, on closer inspection and further workup, have a different cause. Recognition of key features on clinical examination such as the presence of atrophie blanche is key to avoid misdiagnosis of pyoderma gangrenosum and its subsequent treatment with high-dose corticosteroids and other immunosuppressive medications.

Development of pemphigus vegetans and exacerbation of pemphigus foliaceus after secukinumab loading in a patient with complicated generalized pustular psoriasis and pyoderma gangrenosum.

In dermatology, biologics that block signaling pathways of TNF-α, IL-4/IL13, IL-17s, and IL-23 are widely used for the treatment of several inflammatory skin diseases, such as atopic dermatitis and psoriasis. They have shown excellent efficacy with an acceptable safety profile. However, these biologics targeting pathogenic cytokines and their receptors could modulate immunological balance, leading to the development of other inflammatory or autoimmune skin diseases in some cases. In this study, we present a patient who suffered pemphigus vegetans and showed an exacerbation of pemphigus foliaceus after secukinumab loading for the treatment of complicated generalized pustular psoriasis and pyoderma gangrenosum.

Onset of Pyoderma Gangrenosum in Patients on Biologic Therapies: A Systematic Review.

OBJECTIVE: To summarize clinical outcomes of paradoxical pyoderma gangrenosum (PG) onset in patients on biologic therapy. METHODS: The authors conducted MEDLINE and EMBASE searches using PRISMA guidelines to include 57 patients (23 reports). RESULTS: Of the included patients, 71.9% (n = 41/57) noted PG onset after initiating rituximab, 21.1% (n = 12/57) noted tumor necrosis factor α (TNF-α) inhibitors, 5.3% (n = 3/57) reported interleukin 17A inhibitors, and 1.8% (n = 1/57) reported cytotoxic T-lymphocyte-associated protein 4 antibodies. The majority of patients (94.3%) discontinued biologic use. The most common medications used to resolve rituximab-associated PG were intravenous immunoglobulins, oral corticosteroids, and antibiotics, with an average resolution time of 3.3 months. Complete resolution of PG in TNF-α-associated cases occurred within an average of 2.2 months after switching to another TNF-α inhibitor (n = 1), an interleukin 12/23 inhibitor (n = 2), or treatment with systemic corticosteroids and cyclosporine (n = 3), systemic corticosteroids alone (n = 1), or cyclosporine alone (n = 1). CONCLUSIONS: Further investigations are warranted to determine whether PG onset is associated with underlying comorbidities, the use of biologic agents, or a synergistic effect. Nevertheless, PG may develop in patients on rituximab or TNF-α inhibitors, suggesting the need to monitor and treat such adverse effects.

Tyrosine kinase inhibitors-associated pyoderma gangrenosum, a systematic review of published case reports.

Pyoderma gangrenosum is a rare ulcerative dermatosis. It may be caused by some drugs, including small molecule tyrosine kinase inhibitors (TKIs). The aim of this study was to evaluate the reported evidence of pyoderma gangrenosum associated with the use of these drugs. A systematic electronic literature search of PubMed and Embase was conducted. In these databases, search terms describing pyoderma gangrenosum were combined with TKIs. Fifteen case reports (eight cases associated with sunitinib, two with imatinib, two with ibrutinib, one with gefitinib, one with pazopanib, and one with dabrafenib and trametinib) were identified over the 14 years. The average Naranjo score of these cases is 6.6, which indicates a probable adverse drug reaction. Pyoderma gangrenosum is a probable and reversible drug reaction associated with some TKIs. Detailed medical history can help to prompt diagnosis of drug-induced pyoderma gangrenosum. Clinicians should be aware of TKI-associated pyoderma gangrenosum when caring for the skin of oncologic patients undergoing therapy with kinase inhibitors.

Pembrolizumab-associated pyoderma gangrenosum in a patient with metastatic squamous cell carcinoma.

Pyoderma gangrenosum (PG) is a rare, ulcerative neutrophilic dermatosis that has been reported in association with certain medications. Recognition of medications that trigger PG may help to better understand the pathogenesis of the condition and to provide earlier diagnosis and treatment for affected patients. Herein, we report a case of new-onset PG following initiation of the checkpoint inhibitor pembrolizumab for the treatment of metastatic cutaneous squamous cell carcinoma. Our case was resistant to intralesional corticosteroid therapy, but ultimately improved with systemic corticosteroids and cessation of pembrolizumab.