title: [Relationship among the characteristics of anemia, serum level of erythropoietin and the renal tubulointerstitial injury in drug-associated renal parenchymal acute renal failure patients].
abstract: OBJECTIVE
  To recognize the characteristics of anemia in patients with drug-associated renal parenchymal ARF and to investigate the possible relations among Hb, serum level of EPO and the renal tubulointerstitial injury.
  
  
  METHODS
  Sixteen in-patients with drug-associated renal parenchymal ARF (including ATN and ATIN groups) for the last five years and 8 healthy volunteers (control group) were assessed in this study. The general information of these patients was analyzed retrospectively. Anemia related laboratory parameters, serum EPO, serum creatinine (Scr) and the renal tubular function from the samples on the time of renal biopsy in each group were compared. For pathological comparison of renal tubulointerstitial pathological changes, renal biopsy specimens from 5 patients with mild non-IgA mesangial proliferative glomerulonephritis were used as negative controls. The pathological changes in renal tubules and interstitial area were semi-quantitive scored by a computer imaging system. The correlations between Hb and EPO levels, as well as EPO level and renal function or pathological injury index were analyzed, respectively.
  
  
  RESULTS
  There was no significant difference among the ages, genders and the time intervals both from the administration to the onset of the disease and from the onset to the kidney biopsy among ATN and ATIN groups. Scr level was all higher than that in the control group (P<0.05). The renal tubular function injury index and the tubular interstitial pathologic injury index in the two groups were relatively elevated, in which the ATIN group had the highest indexes compared to the others (P<0.01). There were more anemia patients in ATIN group. It showed much lower levels of Hb, Hct and RBC than those in the control group (P<0.01). ATN group possessed fewer anemia patients and the levels of Hb, Hct and RBC remained in the normal range. The remarkable decline of EPO levels was found as 84.8% and 70.7% in the ATN and ATIN groups, respectively (P<0.01). In all patients with renal parenchyma ARF, the levels of Hb and EPO showed an obvious positive correlation (r=0.589, P<0.01), but the negative correlations existed between EPO and Scr, the renal tubular function injury index and renal tubular interstitial pathological injury index, respectively (P<0.05).
  
  
  CONCLUSIONS
  The mechanism of the anemia in the drug-associated parenchymal ARF patients may be due to the lack of intrinsic EPO secretion, mainly induced by acute renal tubular interstitial injury, which contributes to the decreased genesis of red blood cells.
authors.affiliation: Department of Nephrology, Peking University First Hospital, Beijing 100034, China.
authors.forename: Yan-jing
authors.initials: YJ
authors.lastname: Zhang
authors.forename: Xiao-mei
authors.initials: XM
authors.lastname: Li
mesh_terms: D058186:Acute Kidney Injury / Q000139:chemically induced / Q000473:pathology*; D000328:Adult; D000740:Anemia / Q000097:blood / Q000209:etiology / Q000473:pathology*; D003404:Creatinine / Q000097:blood; D004921:Erythropoietin / Q000097:blood*; D005260:Female; D006801:Humans; D008297:Male; D009395:Nephritis, Interstitial / Q000139:chemically induced / Q000150:complications / Q000473:pathology*; D012189:Retrospective Studies
chemical_list: D004921:Erythropoietin; D003404:Creatinine