Disease activity in rheumatoid arthritis: fibrinogen is superior to the erythrocyte sedimentation rate

Erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) are the most widely used assays to measure the laboratory aspect of the acute-phase response, being of great value in monitoring disease activity in rheumatoid arthritis (RA). The ESR is influenced by several factors, and mainly by fibrinogen. Therefore the relationships between ESR, fibrinogen and CRP and their correlations with a patient questionnaire score on activities of daily living, the Modified Stanford Health Assessment Questionnaire (MHAQ) were studied. Fifty-four consecutive patients with RA admitted to the hospital were recruited to this cross-sectional study. Strong mutual correlations were found between the studied acute-phase markers (p<0.000000001). Fibrinogen and CRP rates showed highly significant correlations with MHAQ, whereas ESR did not. We suggest that ESR could be replaced by fibrinogen in the assessment of RA in order more accurately to assess the slower component of the acute-phase response and to have a variable that shows better correlation with disability.     

Relationship between serum ferritin,iron stores and disease activity in rheumatoid arthritis

Summary Bone marrow aspirate from the sternum of 40 patients with active or inactive rheumatoid arthritis (RA) was stained with Perls’ Prussian blue for iron determination. In these patients serum ferritin concentrations were correlated with other indices of iron stores and disease activity. In patients with active RA and without bone marrow iron stores, serum ferritin was significantly lower than in patients with either active or inactive RA and iron stores. In patients with bone marrow iron stores, serum ferritin was directly correlated with erythrocyte sedimentation rate (ESR), Ritchie index, α₁-antitrypsin, α₁-acid glycoprotein and desferrioxamine (DFO)-induced sideruria, while an inverse correlation of serum ferritin with hemoglobin and serum iron was observed. In all patients serum ferritin was significantly correlated only with DFO-induced sideruria and unsaturated iron-binding capacity (UIBC). Thus, serum ferritin is an index of iron stores also in rheumatoid arthritis. In active disease, higher than expected values of serum ferritin are probably due to a shifting of iron from the circulating pool to the reticuloendothelial cells of the synovial membrane.     

Biochemical and genetic markers of iron status and the risk of coronary artery disease: an angiography-based study

BACKGROUND: Iron may promote coronary atherosclerotic disease (CAD) by increasing lipid peroxidation. Studies on biochemical or genetic markers of body iron stores as risk factors for CAD have yielded conflicting results. METHODS: We studied 849 individuals with a clear-cut definition of the CAD phenotype, i.e., with (CAD; n = 546) or without (CAD-free; n = 303) angiographically documented disease. We determined serum ferritin, as a biochemical estimate of iron stores, and the C282Y mutation in the HFE gene, i.e., the main cause of hemochromatosis in Caucasians. The relationships of ferritin with serum markers of either inflammation [C-reactive protein (CRP)] or lipid peroxidation (malondialdehyde) were also investigated. RESULTS: Mean ferritin concentrations were slightly higher in CAD vs CAD-free individuals, but this difference disappeared after adjusting for sex and CRP. Ferritin was significantly correlated with CRP (Spearman's test, rho = 0.129; P <0.001). Heterozygotes for Cys282Tyr were 4.8% among the CAD group and 6.6% among the CAD-free group (P = 0.26). The prevalence of high concentrations of stored iron, defined as ferritin concentrations above the sex-specific upper quintiles of the control distribution, was also similar in the two groups. There was a higher prevalence of "iron depletion" in CAD-free vs CAD females (20% vs 8.8%, respectively), but this difference disappeared after adjustment for age and other cardiovascular risk factors (odds ratio, 0.66; 95% confidence interval, 0.21-2.08). No differences in iron markers were found in CAD patients with or without myocardial infarction. CONCLUSIONS: Our results do not support a role for biochemical or genetic markers of iron stores as predictors of the risk of CAD or its thrombotic complications.     

RA手腕部MRI体积定量分析的有效性评价

目的　建立体积定量分析模型，探讨手、腕部MRI定量分析在类风湿关节炎(Rheumatoid Arthritis, RA）疗效评价中的应用价值。方法　进行定量分析模型预实验及临床前瞻性研究，收集活动期30例并经规律治疗1年的RA患者，应用自主研发软件（昆明理工大学自主研发MRI体积定量分析软件）测量治疗前后同一手腕关节滑膜炎、骨髓水肿体积，并获取入组患者MRI检查同期的红细胞沉降率（Erythrocyte sedimentation rate ESR）、C反应蛋白（C-reactive protein CRP）,计算28 关节疾病活动度（DAS28）。分析治疗前后滑膜炎、骨髓水肿、CRP、ESR、DAS28的变化，并将滑膜炎、骨髓水肿变化量分别与CRP、ESR、DAS28变化量进行相关性分析。结果 体积定量分析模型预实验结果满意，测量精准。与治疗前相比，治疗后患者滑膜炎体积、骨髓水肿范围、CRP、ESR、DAS28均显著降低，差异均有统计学意义(P<0.05)。滑膜炎与骨髓水肿变化量呈强相关（r=0.61，P＜0.00）。滑膜炎、骨髓水肿变化量与ESR、CRP变化量均无明显相关性（r值为0.02-0.32，P均>0.05），滑膜炎、骨髓水肿变化量均与DAS28变化量呈中等相关（r=0.50、0.56，P=0.01、0.00）。 结论　MRI定量分析可作为一种准确客观的量化指标，应用于RA病情监测和疗效评价。     

腕部MRI体积定量分析评价类风湿关节炎疗效

目的探讨腕部MRI体积定量分析对于评价类风湿关节炎(RA)疗效的价值。方法收集30例活动期RA并接受规律治疗1年患者,应用MRI体积定量分析软件测量治疗前后同一腕关节滑膜炎、骨髓水肿体积,并获取同期患者红细胞沉降率(ESR)和C反应蛋白(CRP),计算28关节疾病活动度(DAS28)。分析治疗前后滑膜炎、骨髓水肿、CRP、ESR、DAS28变化,并将滑膜炎、骨髓水肿变化量与CRP、ESR、DAS28变化量进行相关性分析。结果治疗后滑膜炎体积、骨髓水肿范围、CRP、ESR、DAS28均显著降低(P均<0.05)。滑膜炎与骨髓水肿变化量呈正相关(r=0.61,P<0.01)。滑膜炎、骨髓水肿变化量与ESR、CRP变化量均无明显相关(P均>0.05),滑膜炎、骨髓水肿变化量均与DAS28变化量呈正相关(r=0.50、0.56,P=0.01、<0.01)。结论MRI定量分析可作为量化指标,准确客观监测RA病情和评价疗效。     

Association of in vitro oxidative stress, serum ferritin concentration and C-reactive protein in febrile emergency room patients

BACKGROUND: Both C-reactive protein (CRP) and ferritin have been reported to reflect the extent of oxidative stress and inflammation in individual patients and may be useful markers of disease activity and mortality risk. Exposure to oxidative stress has been reported to increase ferritin synthesis. We investigated the relationship between oxidative stress with CRP and ferritin concentrations in febrile emergency room patients to test the hypothesis whether the intensity of oxidative stress correlated with serum ferritin concentration. METHODS: Six normal healthy volunteers and 59 emergency room, febrile patients with body temperature >38.3 we enrolled before receiving medical treatment. Baseline measurements included complete blood count, blood biochemistry, CRP and serum ferritin concentrations, and transferring saturation (TSAT). The intensity of lucigenin-enhanced chemiluminescence (LucCL), corresponding to the level of superoxide, was detected by luminometer. RESULTS: In febrile patients, plasma LucCL intensity was higher than in normal healthy volunteers (P<0.05). The group with bacterial infection had higher serum ferritin (319.4+/-53.7 vs 102.0+/-21.2 ng/dL, P<0.05) and CRP concentrations (7.2+/-1.2 vs 2.2+/-0.6 mg/dL; P<0.05) than the group without bacterial infection. There were no differences in leukocytes (9790+/-606 vs 9577+/-656 /mm3) or plasma LucCL intensity (423.7+/-10.8 vs 409.5+/-6.9 relative light unit?RLU?;) between the two groups. LucCL intensity showed no correlation with serum ferritin concentration (r= -0.0599, P>0.05), TSAT(r= -0.0592, P>0.05), CRP(r= 0.1027, P>0.05) and absolute neutrophil counts (r= 0.1059; P >0.05). CONCLUSION: In this sample of emergency room febrile patients, plasma LucCL intensity was higher than in normal healthy control volunteers. A single point measurement of oxidative stress, particularly plasma LucCL intensity, may not be sufficient to differentiate the origin of fever in febrile patients. These data demonstrate that patients with bacterial infection had increased levels of CRP and ferritin, but this was not associated with LucCL intensity.     

Involvement of leptin in the association between percentage of body fat and cardiovascular risk factors

OBJECTIVES: Recent epidemiologic studies have shown that obesity is associated with elevated blood concentrations of prothrombotic-proinflammatory factors and markers of endothelial dysfunction such as fibrinogen, C-reactive protein (CRP), von Willebrand factor (vWF), and homocysteine. We have assessed whether these markers are associated with percentage of body fat (BF), insulin sensitivity as well as with leptin concentrations. DESIGN AND METHODS: Twenty-five men aged 49.6 +/- 12.7 yr (mean +/- SD) underwent whole-body air displacement plethysmography (Bod-Pod(R)) for estimating BF. Blood analyses for leptin and several other metabolic and cardiovascular markers were carried out. RESULTS: Obese subjects had higher levels as compared to controls of BF (37.5 +/- 5.1 vs. 26.0 +/- 6.6, p < 0.01), fibrinogen (3.30 +/- 0.43 vs. 2.67 +/- 0.11, p < 0.01), vWF (136.4 +/- 50.4% vs. 81.6 +/- 12.6%, p < 0.05), and leptin (17.6 +/- 8.7 vs. 6.2 +/- 3.3, p < 0.01), lower concentrations of HDL-cholesterol (1.09 +/- 0.20 vs. 1.51 +/- 0.10, p < 0.001) and lower QUICKI (1/[log(Ins(0)) + log(Glu(0))]) (0.31 +/- 0.03 vs. 0.34 +/- 0.02, p < 0.05). No significant changes were observed in CRP (5.7 +/- 3.4 vs. 3.8 +/- 1.6, p = 0.327) and homocysteine (9.4 +/- 4.2 vs. 8.3 +/- 0.9, p = 0.749). A positive correlation was observed between BF and fibrinogen (r = 0.67, p = 0.0003). Plasma leptin concentrations were correlated with fibrinogen (r = 0.71, p = 0.0001) and CRP (r = 0.43, p = 0.044). After adjustment for BF leptin emerged as a significant predictor of fibrinogen (beta = 0.47, p = 0.023; R(2) = 0.59, p < 0.001). QUICKI was positively correlated with HDL-cholesterol (r = 0.59, p = 0.010) and negatively with fibrinogen (r = -0.53, p = 0.025), CRP (r = -0.52, p = 0.028) and vWF (r = -0.56, p = 0.013). CONCLUSIONS: Increased BF and impaired insulin sensitivity are associated with increased concentrations of cardiovascular risk factors. Leptin seems to be involved in this elevation and emerges as a predictor of circulating fibrinogen concentrations.     

Influences of hypercholesterolemia on red cell indices and erythrocyte sedimentation rate in elderly persons

BACKGROUND: We investigated whether hypercholesterolemia influenced the values of mean corpuscular volume (MCV) and erythrocyte sedimentation rate (ESR). METHODS: A total of 463 nonanemic elderly persons were evaluated regarding red cell indices, ESR, and ESR-related parameters, such as fibrinogen, albumin, and C-reactive protein (CRP). RESULTS: There were no significant differences in MCV between elderly men with and without hypercholesterolemia (>/=240 mg/dl) nor between the subjects with a marked increase of serum cholesterol concentrations (>/=260 mg/dl) and with severely lowered cholesterol concentrations (<155 mg/dl). ESR in elderly men with hypercholesterolemia averaged 12.3+/-6.8 mm/h, which were significantly higher than in those without hypercholesterolemia (6.0+/-4.7 mm/h, p<0.01). ESR averaged threefold higher in the elderly men with serum cholesterol concentration >/=260 mg/dl versus those with serum cholesterol concentrations <155 mg/dl, although no significant differences were observed in fibrinogen, albumin, and CRP values between the two groups. Serum cholesterol concentrations were higher in elderly men with ESR>/=15.0 mm/h (248.9+/-43.5 mg/dl), compared to those with ESR<2.0 mm/h (199.5+/-31.7 mg/dl, p<0.01). Serum cholesterol concentrations showed no associations with red cell indices but correlated significantly with ESR in elderly men (r=0.24, p<0.01) and postmenopausal women (r=0.21, p<0.01). CONCLUSION: Hypercholesterolemia does not appear to influence MCV but significantly accelerates ESR, especially in elderly men.     

The relationship between the erythrocyte sedimentation rate (ESR) and plasma proteins in clinical materials and models

The relationship between the erythrocyte sedimentation rate (ESR) and plasma proteins was studied within homogenous clinical material and in in vitro models. In acute phase reactions, fibrinogen was the likely cause of the ESR-elevation, but there were significant associations between the ESR and the concentrations of α₁-antitrypsin, C₃, haptoglobin and albumin. In chronic diseases, the ESR-elevation was probably caused by fibrinogen, mono- or polyclonal increase of IgG, IgA, IgM alone or in combinations. In multiple myeloma of the IgG and IgA subtypes, significant correlations were found between the ESR and the monoclonal proteins or between the ESR and the percentage of plasma cells in bone marrow. Model studies showed that the ESR increased linearly with the concentrations of fibrinogen or gammaglobulin (IgG) when these exceeded normal thresholds. The ESR was slightly decreased by increasing concentrations of albumin. Albumin had a synergistic effect on the ESR together with gammaglobulin, but not together with fibrinogen.     

Iron overload, but not treatment with desferrioxamine favours the development of septicemia in patients on maintenance hemodialysis

During a 19-month period we determined the incidence of bacterial infection among 39 patients treated with desferrioxamine who had end-stage renal disease and were undergoing maintenance hemodialysis. Twenty-three received desferrioxamine because of aluminum-related bone disease, and 16 because of iron overload. A control group of 193 patients on maintenance hemodialysis but without desferrioxamine was used. No difference was found in the incidence of septicemia or of all bacterial infections between the patients with aluminum-related bone disease treated with desferrioxamine and the control patients (0.12 vs. 0.12 septicemia per patient-therapy-year, p greater than 0.05; 0.23 vs. 0.26 bacterial infections per patient-therapy-year, p greater than 0.05). The incidence of septicemia in patients treated with desferrioxamine for iron overload, however, was almost three times that in the control patients (0.36 vs. 0.12 septicemia per patient-therapy-year, p less than 0.01). To assess the effect of iron overload itself, we determined the frequency of bacterial infection in patients on regular hemodialysis who have never received desferrioxamine. These were subdivided into three groups according to serum ferritin level which indicated normal or low iron stores (Group I: serum ferritin 10-330 micrograms/l, n = 125), moderate (Group II: serum ferritin 331-1000 micrograms/l, n = 49) or more advanced iron overload (Group III: serum ferritin 1001-2000 micrograms/l, n = 10). Compared to patients with normal or low serum ferritin levels (Group I), we found a significantly higher rate of bacterial infection among patients in Group II compared with Group I (0.18 vs. 0.34 infections per patient-therapy-year, p less than 0.05) and Group III compared with Group I (0.18 vs. 0.58 infections per patient-therapy-year, p less than 0.01). These results suggest that treatment with desferrioxamine does not favour the development of septicemia or bacterial infection independently of iron overload and that iron overload itself may predispose patients on regular hemodialysis to bacterial infection.     

The relationship between the erythrocyte sedimentation rate (ESR) and plasma proteins in clinical materials and models

The relationship between the erythrocyte sedimentation rate (ESR) and plasma proteins was studied within homogenous clinical material and in vitro models. In acute phase reactions, fibrinogen was the likely cause of the ESR-elevation, but there were significant associations between the ESR and the concentrations of alpha 1-antitrypsin, C3, haptoglobin and albumin. In chronic diseases, the ESR-elevation was probably caused by fibrinogen, mono- or polyclonal increase of IgG, IgA, IgM alone or in combinations. In multiple myeloma of the IgG and IgA subtypes, significant correlations were found between the ESR and the monoclonal proteins or between the ESR and the percentage of plasma cells in bone marrow. Model studies showed that the ESR increased linearly with the concentrations of fibrinogen or gammaglobulin (IgG) when these exceeded normal thresholds. The ESR was slightly decreased by increasing concentrations of albumin. Albumin had a synergistic effect on the ESR together with gamma-globulin, but not together with fibrinogen.     

Short-term effects of the TNFalpha antagonist infliximab on the acute phase reaction and activities of daily life in patients with rheumatoid arthritis

OBJECTIVE: To investigate the short-term effects of the tumour necrosis factor alpha (TNFalpha) antagonist infliximab on the acute phase reaction and activities of daily life (ADL) in patients with rheumatoid arthritis (RA). METHODS: Fourteen patients with active RA were treated with an intravenous infusion of 200 mg infliximab. The values of the erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), fibrinogen, granulocyte count, lymphocyte count, platelet count and a patient questionnaire score on ADL, the Health Assessment Questionnaire (HAQ), were obtained at baseline and on days 4 and 14. The significance levels and effect sizes (ESs) of the changes from baseline were calculated. RESULTS: Changes by day 4: The ESs and significance levels were: CRP 1.7, p<0.005; lymphocyte count 1.4, p<0.005; fibrinogen 0.9, p<0.005; ESR 0.7, p<0.005; and HAQ 0.6, p<0.01. Changes by day 14: CRP 1.6, p<0.005; ESR 1.5, p<0.005; fibrinogen 1.3, p<0.005; lymphocyte count 1.0, p<0.005; granulocyte count 0.7, p<0.05; and HAQ 0.6, p<0.05. CONCLUSION: CRP, fibrinogen and ESR showed the largest ESs and were thus the most sensitive variables showing the early effect of infliximab in this study. The score on ADL (HAQ) showed less ES, but still significant short-term improvements.     

强直性脊柱炎铁蛋白的变化及相关性研究

目的观察强直性脊柱炎（ankylosingsp ondyiltis,AS）患者的铁蛋白的变化及其与病情活动指标的相关性。方法检测40例活动期AS患者铁蛋白、各活动性指标（ESR、CRP）及免疫球蛋白（IgA、IgG、IgM）,另设正常对照组30例并检测上述指标;分析40例活动期AS患者铁蛋白与活动性指标的相关性。结果①与正常对照组相比,活动期AS患者铁蛋白、ESR、CRP、IgG、IgA明显增高（P〈0．05或P〈0．01）,而IgM无统计学意义（P〉0．05）;②铁蛋白与ESR、CRP明显正相关（P〈0．05或P〈0．01）,与IgA、IgG、IgM无明显相关性（P〉0．05）。结论活动期AS患者出现了铁蛋白、IgA、IgG的升高,且铁蛋白的升高与ESR、CRP具有相关性,IgA、IgG的升高提示活动期AS患者存在免疫紊乱,提示铁蛋白可以作为反应AS疾病活动性的一项客观指标,其升高机制可能是由于炎症因子的释放导致的免疫紊乱。     

Ferritin and other acute phase proteins in various forms of coronary heart disease

The purpose of the study was to determine clinical importance of high serum levels of ferritin, fibrinogen and C-reactive protein (CRP) in patients with various forms of coronary heart disease (CHD) such as stable angina, painless myocardial ischemia (PMI) and instable angina (IA). The subjects of the study were 60 patients with CHD, whose clinical variant (stable angina, PMI or IA) had been determined by stress echocardiography. The control group consisted of 20 patients, not suffering from CHD, but having cardiovascular risk factors (arterial hypertension, dyslipoproteinemia, male gender, obesity, elderly age). All patients underwent routine clinical examination and biochemical blood tests. Serum levels of CRP, fibrinogen and ferritin were highest in the patients with IA and significantly differed from those in the control group. The difference in serum iron levels and total iron-binding capacity in serum (TIBC) between the groups were insignificant. Correlations between serum level of iron, TIBC and ferritin level were found neither in CHD patients (r = 0.1) nor in the control group (r = 0.15). No correlation between serum level of ferritin and CRP level was observed in the control group, but in all CHD groups this correlation was significant. The strongest correlation between these values was observed in the patients with IA. Besides, correlations between serum levels of ferritin and CRP (r = 0.46, p < 0.02) and between ferritin and fibrinogen levels (r = 0.39, p < 0.05) were found in the patients with IA. In patients with CHD, especially those who have IA, serum ferritin should be considered among acute phase proteins, reflecting destabilization of atherosclerotic plaque.     

C-reactive protein and all-cause mortality in a large hospital-based cohort

BACKGROUND: C-reactive protein (CRP), an acute-phase protein, is a sensitive systemic marker of inflammation and acute-phase reactions. Testing CRP concentrations at hospital admission may provide information about disease risk and overall survival. METHODS: All first-ever transmittals to the department of medical and chemical laboratory diagnostics for determination of low-sensitivity CRP (n = 274 515, 44.5% male, median age 51 years) between January 1991 and July 2003 were included [median follow-up time: 4.4 years (interquartile range, 2.3-7.4 years)]. The primary endpoint was all-cause mortality. Multivariate Cox regression adjusted for sex and age was applied for analysis. RESULTS: Compared to individuals within the reference category (CRP <5 mg/L), hazard ratios (HR) for all-cause mortality increased from 1.4 (5-10 mg/L category) to 3.3 in the highest category (>80 mg/L, all P <0.001). CRP was associated with various causes of death. The relation of CRP to cancer death was stronger than to vascular death. Younger patients with increased CRP had relatively far worse outcome than older patients (maximal HR: < or =30 years: 6.7 vs >60 years: 1.7-3.7). Interestingly, both short- and long-term mortality were associated with increasing CRP concentrations (>80 mg/L: HR 22.8 vs 1.4). CONCLUSION: Measurement of low-sensitivity CRP at hospital admission allowed for the identification of patients at increased risk of unfavorable outcome. Our findings indicate that close attention should be paid to hospitalized patients with high CRP not only because of very substantial short-term risk, but also long-term excess risk, the basis for which needs to be determined.     

A comparison between serum ferritin concentration and the amount of bone marrow stainable iron

There was good parallelism between serum ferritin levels and the amount of bone marrow stainable iron in 123 patients with gastritis, gastric ulcer and duodenal ulcer. A serum ferritin concentration of about 20-25 micrograms/l is the approximate level below which stainable iron cannot be demonstrated in the bone marrow.     

A comparison between serum ferritin concentration and the amount of bone marrow stainable iron

There was good parallelism between serum ferritin levels and the amount of bone marrow stainable iron in 123 patients with gastritis, gastric ulcer and duodenal ulcer. A serum ferritin concentration of about 20-25 μg/l is the approximate level below which stainable iron cannot be demonstrated in the bone marrow.     

Association of increased ferritin with premature coronary stenosis in men

BACKGROUND: Body iron status has been implicated in atherosclerotic cardiovascular disease. The main hypothesis is that high iron status is associated with increased oxidation of LDL. We investigated the potential role of ferritin as an additional risk factor promoting atherosclerosis among a young population with coronary artery disease (CAD). METHODS: Four hundred consecutive patients (218 males, 182 females) referred for diagnostic coronary angiography were examined, and risk factors for CAD, lipids, C-reactive protein (CRP), and ferritin concentrations were recorded for all participants. RESULTS: Ferritin was higher in the male patients with CAD (121 microg/L; range, 56-258 microg/L) than in the men without significant CAD (73 microg/L; range, 32-138 microg/L; P <0.002). Multiple logistic regression analysis, after adjustment for the established coronary risk factors, showed ferritin as an independent discriminating risk factor for CAD (P <0.01). Men in the highest quartile of ferritin had an odds ratio (OR) of 1.62 [95% confidence interval (95% CI), 1.12-2.42; P <0.01] compared with men in the lowest quartile of ferritin. The association between ferritin and CAD was more pronounced in male patients < or =50 years (OR = 2.65; 95% CI, 1.35-5.51; P <0.003). Ferritin was significantly higher in diabetic male patients in comparison with nondiabetic male patients [168 microg/L (range, 74-406 microg/L) vs 106 microg/L (range, 44-221 microg/L), respectively; P <0.002]. No association was observed between ferritin and CAD among the female patients. CONCLUSION: Our data suggest that increased ferritin might be an independent predictor of premature CAD in male Iranian patients.     

Procalcitonin and conventional markers of inflammation in peritoneal dialysis patients and peritonitis.

OBJECTIVES: To determine the significance of a newly described marker of inflammation procalcitonin (PCT), and to investigate its relationship to conventional markers of inflammation, such as C-reactive protein (CRP), fibrinogen, and erythrocyte sedimentation rate (ESR), in patients on peritoneal dialysis (PD) and with peritonitis. DESIGN: A prospective, observational clinical study. SETTING: The Nephrology Division of a University-affiliated teaching hospital. PATIENTS AND METHODS: 51 consecutive patients on PD were included in the study. Of this number, 16 developed peritonitis during the observational period. Baseline PCT, CRP, and fibrinogen concentrations and ESR of 51 PD patients were determined at a time point (TB) prior to any evidence of infection. These results were compared with laboratory values from 74 hemodialysis patients and 34 nonuremic control subjects. All PD patients then were followed prospectively for evidence of peritonitis. In addition to routine blood tests, including hemoglobin and leukocyte count, and routine biochemical tests, blood samples were taken to measure PCT, CRP, and fibrinogen concentrations and ESR at the time (T0) when patients first were diagnosed with PD peritonitis and also on the 4th (T4) and the 14th (T14) days after treatment for peritonitis was initiated. PCT was assayed by immunoluminometry. RESULTS: No significant difference was observed between baseline median serum PCT concentrations in PD and hemodialysis patients; however, in both groups, baseline median PCT concentrations were significantly higher than those of nonuremic controls (p < 0.05). The 16 patients on PD who developed peritonitis had 21 PD peritonitis episodes during the study period. The increased PCT concentration observed at T0 in PD peritonitis episodes decreased with therapy, and this change was statistically significant (p < 0.05). In a receiver operating characteristic curve analysis for peritonitis, the area under the curve (AUC) for PCT was 0.80, which was significantly lower than the AUC for CRP and greater than the AUCs for fibrinogen and ESR. The sensitivity of PCT for peritonitis was lower than the sensitivity of conventional markers of inflammation; however, the specificity of PCT was higher. CONCLUSIONS: Median serum PCT concentration in PD patients was significantly higher than in nonuremic controls but not hemodialysis patients. Serum PCT concentrations may serve as a useful adjunct to traditional markers of inflammation in detecting and monitoring inflammation and peritonitis in PD patients.     

Impact of parturition on iron status in nonanaemic iron deficiency

BACKGROUND: Iron-deficient nonanaemic parturients risk underdiagnosis as a result of the reliance on postpartum ferritin and haemoglobin as markers of iron status. Ferritin is an acute-phase protein whose levels increase during the inflammatory response, as occurs after delivery. Our aims were to evaluate the impact of parturition on iron status, erythropoiesis and the inflammatory response, and identify the optimal parameters and timing for diagnosing iron deficiency in the presence of postpartum inflammation. MATERIALS AND METHODS: Conventional parameters of iron status, erythropoiesis and the inflammatory response (serum ferritin, serum iron, transferrin saturation, C-reactive protein) were compared with more recent parameters [soluble transferrin receptors (sTfR), hypochromic red cells, reticulocyte indices] within 48 h either side of delivery in 64 iron-deficient nonanaemic women (defined by a prepartum serum ferritin < or =15 microg L(-1), and a pre- and postpartum haemoglobin of > or =11.0 g dL(-1) and > or =10.0 g dL(-1), respectively). RESULTS: Mean sTfR decreased pre to postpartum from 7.3 to 5.8 microg mL(-1) (P<0.01), while mean serum ferritin increased from 9.7 to 16.9 microg L(-1) (P<0.01). Serum ferritin did not correlate with haemoglobin pre or postpartum (r=0.04, P=0.7; r=0.2, P=0.09), but a correlation persisted postpartum between hypochromic red blood cells and haemoglobin (r=-0.26; P<0.05). The percentage of hypochromic red cells remained virtually unchanged pre- and postpartum (4.0% vs. 3.8%; NS). Postpartum mean reticulocyte haemoglobin content (CHr) was 27.1 +/- 1.6 pg. CONCLUSION: Iron status should be tested prepartum, in the absence of an inflammatory response, rather than in the early postpartum. A valuable additional parameter, where available, might be the hypochromic red cell percentage, which is virtually uninfluenced by the inflammatory response. Furthermore, hypochromic red cell percentage, CHr and sTfR can be helpful to differentiate between functional iron deficiency and depleted iron stores.