title: HPV type in plantar warts influences natural course and treatment response: secondary analysis of a randomised controlled trial.
abstract: BACKGROUND
  Cryotherapy is effective for common warts, but for plantar warts available treatments often fail.
  
  
  OBJECTIVE
  Within a pragmatic randomised controlled trial, we examined whether subgroups of common and plantar warts have a favourable natural course or response to treatment based on wart-associated HPV type.
  
  
  METHODS
  Consecutive patients with new common or plantar warts were recruited in 30 Dutch family practices. Patients (n=250) were randomly allocated to liquid-nitrogen cryotherapy, 40% salicylic acid self-application, or wait-and-see policy. Before treatment, swabs were taken from all separate warts and analysed by a broad spectrum HPV genotyping assay. At 13 weeks, cure rates with 95% confidence intervals of common and plantar warts on intention to treat basis were compared between treatment arms for the different wart-associated HPV types.
  
  
  RESULTS
  In total, 7% of swabs tested negative for HPV DNA and 16% contained multiple types, leaving 278 of 371 common swabs (75%) and 299 of 373 plantar swabs (80%) with a single type for analysis. After wait-and-see policy, cure rates were 2/70 (3%, 95% confidence interval 1-10) for HPV 2/27/57-associated common warts, 4/58 (7%, 3-16) for HPV 2/27/57-associated plantar warts, and 21/36 (58%, 42-73) for HPV 1-associated plantar warts. After cryotherapy, cure rates were 30/44 (68%, 53-80), 6/56 (11%, 5-21), and 15/23 (65%, 45-81); after salicylic acid 16/87 (18%, 12-28), 15/60 (25%, 16-37), and 24/26 (92%, 76-98), respectively.
  
  
  CONCLUSIONS
  HPV type influenced the natural course and response to treatment for plantar warts. HPV testing potentially optimises wart treatment in primary care.
authors.affiliation: Department of Public Health and Primary Care, Leiden University Medical Center, Leiden, The Netherlands. s.c.bruggink@lumc.nl
authors.forename: Sjoerd C
authors.initials: SC
authors.lastname: Bruggink
authors.forename: Jacobijn
authors.initials: J
authors.lastname: Gussekloo
authors.forename: Maurits N C
authors.initials: MN
authors.lastname: de Koning
authors.forename: Mariet C W
authors.initials: MC
authors.lastname: Feltkamp
authors.forename: Jan Nico Bouwes
authors.initials: JN
authors.lastname: Bavinck
authors.forename: Wim G V
authors.initials: WG
authors.lastname: Quint
authors.forename: Willem J J
authors.initials: WJ
authors.lastname: Assendelft
authors.forename: Just A H
authors.initials: JA
authors.lastname: Eekhof
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D002675:Child, Preschool; D017679:Cryotherapy / Q000379:methods; D004279:DNA, Viral / Q000235:genetics; D004358:Drug Therapy / Q000379:methods; D005260:Female; D005534:Foot Diseases / Q000628:therapy* / Q000821:virology*; D005838:Genotype; D006801:Humans; D008297:Male; D008875:Middle Aged; D009426:Netherlands; D027383:Papillomaviridae / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification; D030361:Papillomavirus Infections / Q000628:therapy* / Q000821:virology*; D020156:Salicylic Acid / Q000008:administration & dosage; D016896:Treatment Outcome; D014860:Warts / Q000628:therapy* / Q000821:virology*; D055815:Young Adult
chemical_list: D004279:DNA, Viral; D020156:Salicylic Acid