Pityriasis rubra pilaris (PRP) is a rare chronic inflammatory papulosquamous dermatosis affecting both adults and children. Six subtypes of PRP have been described. Recently, the management of PRP with biologic immunosuppressive agents regularly used in psoriasis has been supported by several case reports and series. Ustekinumab is an anti-IL12/23 IgG1 kappa human monoclonal antibody. It has been approved for the treatment of Crohn's disease, plaque psoriasis, psoriatic arthritis and ulcerative colitis. It has also been reported to be effective as an off-label treatment for PRP. Current data are equivocal regarding infectious disease risk with ustekinumab administration. We describe a case of meningococcal and HSV-2 infection of the central nervous system in a patient being treated with ustekinumab for PRP.
Learning points:
The administration of biologic immunosuppressive agents can result in severe life-threatening infections.Research is required on the infection potential of ustekinumab.Physicians should be aware of the possibility of infectious disease when prescribing biologic agents.Vaccination is essential in immunosuppressed adults.