title: Red Cell Distribution Width and Mean Platelet Volume in Patients With Pityriasis Rosea.
abstract: BACKGROUND
  Pityriasis rosea (PR) is an inflammatory skin disorder of unknown etiology. However, it is suggested to be related with the reactivation of human herpes virus 7 (HHV-7) and/or HHV-6. It is sometimes diffucult to distinguish PR from PR-like drug eruptions and other inflammatory disorders, so we need new parameters which are cheap and easy in determining PR. Red blood cell distribution width (RDW) and mean platelet volume (MPV) have been studied as inflammatory markers in recent studies. However, the RDW and MPV in PR patients have not been investigated. This is the first study investigating RDW and MPV parameters in PR.
  
  
  METHODS
  This was a retrospective study of 127 patients and 127 healthy controls. MPV, RDW and the other laboratory tests were recorded.
  
  
  RESULTS
  RDW levels of patients with PR were significantly lower than those of the controls (13.66 ± 2.68 and 14.00 ± 1.39, P < 0.01). The other inflammatory markers such as MPV (9.97 ± 0.99 and 10.0 ± 1.06, P = 0.7) and platelet (2.66.29 ± 62.85 and 277.41 ± 63.50, P = 0.3) were studied and statistically significant differences were not obtained. There were no significant differences found between the patient group and healthy controls in terms of hemoglobin, hematocrite, C-reactive protein (CRP), sedimentation, mean corpuscular volume (MCV), aspartate aminotransferase (AST), red blood cell (RBC), alanine aminotransferase (ALT), blood urea nitrogen (BUN), and creatinine parameters (P > 0.05).
  
  
  CONCLUSIONS
  RDW can be used as a marker in diagnosing PR.
authors.affiliation: Department of Dermatology, Samsun State Hospital, Samsun, Turkey.
authors.forename: Gunseli Sefika
authors.initials: GS
authors.lastname: Pancar
authors.affiliation: Department of Statistics, Ondokuz Mayis University School of Medicine Samsun, Turkey.
authors.forename: Oznur
authors.initials: O
authors.lastname: Eyupoglu
keywords: Laboratory parameters; Mean platelet volume; Pityriasis rosea; Red blood cell distrubution width