title: Prolonged urinary retention after collagen periurethral injections: a sequela of humoral immunity.
abstract: BACKGROUND
  Approximately 3% of candidates for collagen periurethral injections are ineligible because of an immediate hypersensitivity reaction to skin testing. After a negative skin test, physicians believe patients should be free of any adverse clinical events from hypersensitivity reactions. We present a patient who developed prolonged urinary retention from a delayed hypersensitivity reaction after negative skin testing.
  
  
  METHODS
  After a negative skin test, a 51-year-old woman underwent collagen periurethral injections for recurrent genuine stress incontinence associated with a fixed bladder neck. After reporting complete resolution of symptoms, she developed complete urinary retention associated with a delayed hypersensitivity reaction at both the skin test and injection sites. Her retention resolved after a year of intermittent catheterization and antibiotics for persistent urinary tract infection.
  
  
  CONCLUSIONS
  Delayed hypersensitivity reactions may be associated with an adverse clinical event in up to 2.5% of patients despite a negative skin test. After skin testing, physicians should counsel their patients accordingly.
authors.affiliation: Section of Urogynecology and Reconstructive Pelvic Surgery, Department of Obstetrics and Gynecology, University of Louisville Health Science Center, Kentucky 40202, USA.
authors.forename: M
authors.initials: M
authors.lastname: Heit
mesh_terms: D003094:Collagen / Q000276:immunology* / Q000627:therapeutic use*; D003432:Cross-Linking Reagents / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D006968:Hypersensitivity, Delayed / Q000150:complications / Q000209:etiology*; D008875:Middle Aged; D019736:Prostheses and Implants; D012882:Skin Tests; D014550:Urinary Incontinence, Stress / Q000628:therapy; D016055:Urinary Retention / Q000209:etiology*
chemical_list: D003432:Cross-Linking Reagents; D003094:Collagen