[Ecthyma gangrenosum]. / Ecthyma gangrenosum.

Ecthyma gangrenosum (EG) is a severe potentially lethal cutaneous infection that progresses sequentially from maculopapular rash to haemorrhagic bulla and then to necrotic ulceration with surrounding erythema. It usually occurs in immunocompromised patients (aplasia secondary to chemotherapy, HIV infection, neutropenia or functional deficit of neutrophils, agammaglobulinemia). It rarely affects healthy people. Differential diagnosis includes leishmaniasis, pyoderma gangrenosum, eschars and papulonecrotic tuberculides. Blood cultures and/or local sample allow the isolation of P. aeruginosa, which is the causative germ. Treatment is based on suitable parenteral antibiotic therapy according to results of susceptibility tests (third-generation cephalosporins, fluoroquinolones). We here report the case of a 2-year old child with no particular past medical history presenting with multiple necrotic ulcers on the back with erythematous border evolving in a febrile context. Blood culture was negative. Laboratory tests showed sedimentation rate 30 mm, CRP 80mg/l. Bacteriological sampling of pus revealed pseudomonas aeruginosa. The diagnosis of ecthyma gangrenosum was made. The patient underwent parenteral third-generation cephalosporins. Complete patient recovery with healing occurred after 4 weeks.

Observational case series on adalimumab-induced paradoxical hidradenitis suppurativa.

INTRODUCTION: Although the efficacy of TNF blockers has been demonstrated in hidradenitis suppurativa (HS), many paradoxical effects have also been described with TNF antagonists. We wished to describe patients with adalimumab (ADA)-induced paradoxical HS. METHODS: This is a retrospective descriptive case series of four patients with ADA-induced paradoxical HS. RESULTS: All the patients had a good response to TNFa antagonist therapy at the time of HS occurrence. The time from TNFa antagonist initiation to HS onset or exacerbation ranged from a few weeks to 24 months. The outcome of HS was variable. Systemic antibiotics were required in all the cases to control HS. TNF blockers were continued in three cases with a switch to another anti-TNF class in one case. Switch to ustekinumab was prescribed in one patient with SA and Crohn's disease. CONCLUSION: Although the imputability of TNF blockers in paradoxical HS is still debatable, further research and observation are needed to confirm and distinguish patients with genetic and clinical predisposition in the onset or exacerbation of HS during anti-TNF treatment.