Herpes simplex virus encephalitis in a patient receiving ustekinumab associated with extensive cerebral oedema and brainshift successfully treated by immunosuppression with dexamethasone

Incidence, risk factors, and consequences of human alphaherpesvirus infections in patients with psoriasis who initiate methotrexate or biologic agents

BACKGROUND

Immunosuppressive agents may increase the risk of infections with human alphaherpesviruses.

METHODS

We included all adult patients with moderate to severe psoriasis who initiated methotrexate (MTX) or biologic agents in a retrospective cohort study. An episode of alphaherpesviruses infection was defined as filling a prescription for systemic acyclovir, valacyclovir, or famciclovir. Using nation-wide registries, we determined the incidence, risk factors, 180-days hospital contacts, and 30-days mortality following infection.

RESULTS

We included 7,294 patients; 4,978 (68%) received MTX, and 2,316 (32%) biologic agents. The incidence rates [95% CI] of alphaherpesviruses were 23 [20-27], 26 [19-35], 17 [11-27] and 6.7 [1.3-21] per 1000 PYFU in patients on MTX, TNFα-, IL-12/23-, and IL-17 inhibitors, respectively. Males had an unadjusted HR of 0.47 (P < 0.001) for alphaherpesvirus infection. Patients on IL-17 inhibitors had an adjusted HR of 0.24 (P = 0.048) compared to TNFα inhibitors. Within 180-days after infection, 13%, 7.5%, and <0.5% of patients on MTX, TNFα inhibitors, and IL-12/23 or IL-17 inhibitors, respectively, had hospital contacts, and the 30-days mortality for all groups was <0.5%.

CONCLUSIONS

The incidence and risk of alphaherpesvirus infections was comparable between patients on MTX and TNFα inhibitors, while use of IL-17 inhibitors was associated with a lower risk.

Clinically reversible ustekinumab-induced encephalopathy: case report and review of the literature

Ustekinumab, a monoclonal antibody against interleukin (IL)-12 and IL-23 approved for the treatment of Crohn’s disease, has shown to be an effective therapy with a favourable safety profile. Clinical trials and real-world studies have reported very few neurological adverse events, including posterior reversible encephalopathy syndrome, idiopathic intracranial hypertension and headache. We describe the case of a 48-year-old man with Crohn’s disease who initiated treatment with ustekinumab on top of ongoing treatment with methotrexate 25 mg/week who presented with an acute-onset encephalopathy that rapidly evolved to severe tetraparesis and akinetic mutism, associated with extensive leukoencephalopathy and restricted diffusion on brain magnetic resonance imaging (MRI), 1 month after the second dose of ustekinumab. Comprehensive in-patient diagnostic testing ruled out vascular, demyelinating, metabolic, tumoral and infectious etiologies. Brain biopsy showed patchy infiltrates of foamy histiocytes with perivascular distribution, associated with edema, diffuse astrocytic gliosis and focal perivascular axonal destruction without demyelination, and ustekinumab-induced neurotoxicity was suspected. After drug discontinuation, the patient presented a complete clinical recovery despite the persistence of leukoencephalopathy. In conclusion, in an era in which biological therapies are continually evolving and expanding, knowledge about the potential neurotoxicity of these new therapies and their management becomes crucial. Although ustekinumab-induced encephalopathy is uncommon, the recognition of this potentially serious side effect is important because prompt withdrawal is associated with a favourable outcome. Whether methotrexate played an additional contributing role is currently unknown, but it is a factor that should be considered.

A Case of Meningococcal and HSV-2 Meningitis in a Patient Being Treated with Ustekinumab for Pityriasis Rubra Pilaris

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.