title: Anemia and thrombocytosis induced by ribavirin monotherapy in patients with chronic hepatitis C.
abstract: BACKGROUND
  An inosine triphosphatase (ITPA) single-nucleotide polymorphism (SNP) is associated with anemia induced by pegylated interferon and ribavirin (RBV) combination therapy in patients with chronic hepatitis C (CHC). However, there are very few reports on the hematological effects of RBV monotherapy. Here, hematological changes were monitored in patients with CHC who received RBV monotherapy, and the mechanism of these changes was investigated.
  
  
  METHODS
  Patients with CHC (n = 30) received RBV monotherapy for 4 weeks. The RBV dose was determined on the basis of body weight. Complete blood count, and serum erythropoietin (EPO) and thrombopoietin (TPO) levels were assessed. The associations between these parameters and the ITPA SNP (rs1127354) were analyzed.
  
  
  RESULTS
  Over the 4 weeks, the median hemoglobin level of all patients decreased significantly, from 13.6 (10.5-16.6) to 11.7 (9.4-14.9) g/dl (P < 0.001), and the platelet counts increased, from 14.0 × 10(4) (8.9-37.4 × 10(4)) to 15.8 × 10(4) (10.2-40.6 × 10(4)) /mm(3) (P = 0.003). At week 4, hemoglobin levels differed between patients with the ITPA CC genotype and those with the AA or AC genotypes [11.1 (9.4-13.5) vs. 12.9 (12.5-14.9) g/dl, P = 0.001]. The platelet change ratio (i.e., platelet count at week 4/platelet count at baseline) in the patients with developing anemia was correlated with the increase in the serum EPO level over 4 weeks (r = 0.88, P = 0.002), but not with the increase in the serum TPO level over 4 weeks.
  
  
  CONCLUSIONS
  RBV monotherapy induced anemia and affected thrombocytosis in patients with CHC. Elevated endogenous EPO may stimulate platelet production.
authors.affiliation: Department of Gastroenterology, Hokkaido University Hospital, North 17 Jo, West 5 Cho-me, Kita-ku, Sapporo 060-8638, Japan. tk990063@med.hokudai.ac.jp
authors.forename: Tomoe
authors.initials: T
authors.lastname: Kobayashi
authors.forename: Shuhei
authors.initials: S
authors.lastname: Hige
authors.forename: Katsumi
authors.initials: K
authors.lastname: Terashita
authors.forename: Masato
authors.initials: M
authors.lastname: Nakai
authors.forename: Hiromasa
authors.initials: H
authors.lastname: Horimoto
authors.forename: Takuya
authors.initials: T
authors.lastname: Sho
authors.forename: Mitsuru
authors.initials: M
authors.lastname: Nakanishi
authors.forename: Koji
authors.initials: K
authors.lastname: Ogawa
authors.forename: Makoto
authors.initials: M
authors.lastname: Chuma
authors.forename: Naoya
authors.initials: N
authors.lastname: Sakamoto
authors.forename: Masahiro
authors.initials: M
authors.lastname: Asaka
mesh_terms: D000328:Adult; D000368:Aged; D000740:Anemia / Q000139:chemically induced*; D000998:Antiviral Agents / Q000009:adverse effects* / Q000627:therapeutic use; D004921:Erythropoietin / Q000097:blood; D005260:Female; D005838:Genotype; D006454:Hemoglobins / Q000378:metabolism; D019698:Hepatitis C, Chronic / Q000188:drug therapy; D006801:Humans; D008297:Male; D008875:Middle Aged; D010976:Platelet Count; D020641:Polymorphism, Single Nucleotide; D011755:Pyrophosphatases / Q000235:genetics*; D012254:Ribavirin / Q000009:adverse effects* / Q000627:therapeutic use; D013922:Thrombocytosis / Q000139:chemically induced*; D000097630:Inosine Triphosphatase
chemical_list: D000998:Antiviral Agents; D004921:Erythropoietin; D006454:Hemoglobins; D011755:Pyrophosphatases; D012254:Ribavirin; D000097630:Inosine Triphosphatase