title: Development of psoriasis in IBD patients under TNF-antagonist therapy is associated neither with anti-TNF-antagonist antibodies nor trough levels.
abstract: BACKGROUND
  The cause of anti-TNF-induced psoriasis is still unknown.
  
  
  OBJECTIVE
  We aimed to evaluate if the appearance of psoriasis under anti-TNF therapy is associated with anti-TNF antibody levels and TNF-antagonist trough levels.
  
  
  METHODS
  In this case-control study we identified 23 patients (21 with Crohn's disease [CD], two with ulcerative colitis [UC]) who developed psoriasis under infliximab (IFX, n = 20), adalimumab (ADA, n = 2), and certolizumab pegol (CZP, n= 1) and compared them regarding the anti-TNF-antagonist antibody levels with 85 IBD patients (72 with CD, 13 with UC) on anti-TNF therapy without psoriasis.
  
  
  RESULTS
  Median disease duration was not different between the two groups (7 years in the group with psoriasis under TNF-antagonists vs. 10 years in the control group, p = 0.072). No patient from the psoriasis group had antibodies against TNF-antagonists compared to 10.6% in the control group (p = 0.103). No difference was found in IFX trough levels in the group of patients with psoriasis compared to the control group (2.6 μg/mL [IQR 0.9-5.5] vs. 3.4 μg/mL [IQR 1.4-8.1], p = 0.573). TNF-antagonist therapy could be continued in 91.3% of patients with TNF-antagonist related psoriasis and most patients responded to topical therapies.
  
  
  CONCLUSIONS
  Anti-TNF-induced psoriasis seems to be independent of anti-TNF antibodies and trough levels. Interruption of Anti-TNF therapy is rarely necessary.
authors.affiliation: a Department of Gastroenterology , University Hospital Zvezdara , Belgrade , Serbia.
authors.forename: Marijana
authors.initials: M
authors.lastname: Protic
authors.affiliation: b Division of Gastroenterology and Hepatology , Center Hospitalier Universitaire Vaudois , Lausanne , Switzerland.
authors.forename: Alain
authors.initials: A
authors.lastname: Schoepfer
authors.affiliation: c Department of Dermatology , University Hospital Bern , Bern , Switzerland.
authors.forename: Nikhil
authors.initials: N
authors.lastname: Yawalkar
authors.affiliation: d Department of Gastroenterology and Hepatology , Stadtspital Triemli , Zürich , Switzerland.
authors.forename: Stephan
authors.initials: S
authors.lastname: Vavricka
authors.affiliation: e Division of Gastroenterology and Hepatology , University Hospital Fribourg , Fribourg , Switzerland.
authors.forename: Frank
authors.initials: F
authors.lastname: Seibold
mesh_terms: D000068879:Adalimumab / Q000009:adverse effects / Q000627:therapeutic use*; D000293:Adolescent; D000328:Adult; D016022:Case-Control Studies; D000068582:Certolizumab Pegol / Q000009:adverse effects / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D015212:Inflammatory Bowel Diseases / Q000150:complications* / Q000188:drug therapy*; D000069285:Infliximab / Q000009:adverse effects / Q000627:therapeutic use*; D016015:Logistic Models; D008297:Male; D015999:Multivariate Analysis; D011565:Psoriasis / Q000209:etiology*; D013557:Switzerland; D016896:Treatment Outcome; D014409:Tumor Necrosis Factor-alpha / Q000037:antagonists & inhibitors*; D055815:Young Adult
chemical_list: D014409:Tumor Necrosis Factor-alpha; D000069285:Infliximab; D000068879:Adalimumab; D000068582:Certolizumab Pegol
keywords: Crohn’s disease; Psoriasis; adalimumab; certolizumab pegol; inflammatory bowel disease; infliximab; ulcerative colitis