RESUMO
Long-term observation of patients with ANCA-associated vasculitis (AAV) allows the identification of different longitudinal patterns of ANCA levels during follow-up. This study aimed to characterize these patterns and to determine their prognostic significance. All ANCA determinations performed in two university hospitals during a 2-year period were retrospectively reviewed. Patients were included in the analysis if they had high titers of anti-myeloperoxidase (anti-MPO) or anti-proteinase 3 (anti-PR3) antibodies at least once, ≥ 5 serial ANCA determinations and AAV diagnosed by biopsy or American College of Rheumatology (ACR) classification criteria. Patients' time-course ANCA patterns were classified as monophasic, remitting, recurrent or persistent. Associations between ANCA patterns and prognostic variables (relapse rate and renal outcome) were analysed by univariate and multivariate statistics. A total of 99 patients [55 with microscopic polyangiitis (MPA), 36 with granulomatosis with polyangiitis (GPA) and eight with eosinophilic granulomatosis with polyangiitis (EGPA)] were included. Median follow-up was 9 years. Among patients diagnosed with MPA or GPA, recurrent or persistent ANCA patterns were associated with a higher risk of clinical relapse [hazard ratio (HR) = 3·7, 95% confidence interval (CI) = 1·5-9·1 and HR = 2·9, 95% CI = 1·1-8·0, respectively], independently of clinical diagnosis or ANCA specificity. In patients with anti-MPO antibodies, the recurrent ANCA pattern was associated with worsening renal function [odds ratio (OR) = 5·7, 95% CI = 1·2-26·0]. Recurrent or persistent ANCA patterns are associated with a higher risk of clinical relapse. A recurrent ANCA pattern was associated with worsening renal function in anti-MPO-associated vasculitis.
Assuntos
Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/patologia , Anticorpos Anticitoplasma de Neutrófilos/metabolismo , Rim/patologia , Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/metabolismo , Biópsia , Doença Crônica , Síndrome de Churg-Strauss/metabolismo , Síndrome de Churg-Strauss/patologia , Feminino , Seguimentos , Granulomatose com Poliangiite/patologia , Humanos , Rim/metabolismo , Masculino , Poliangiite Microscópica/metabolismo , Poliangiite Microscópica/patologia , Pessoa de Meia-Idade , Mieloblastina/metabolismo , Peroxidase/metabolismo , Prognóstico , Recidiva , Estudos RetrospectivosRESUMO
Regulatory T cells (T(regs)) are crucial in the maintenance of the immune tolerance and seem to have an important role in systemic sclerosis (SSc). The interleukin 2 receptor α (IL2RA) is an important T(reg) marker, and polymorphisms of IL2RA gene are associated with a number of autoimmune diseases. Therefore, we aimed to investigate for the first time the association of the IL2RA locus in SSc. For this purpose, a total of 3023 SSc patients and 2735 matched healthy controls, from six European Caucasian cohorts, were genotyped for the IL2RA gene variants rs11594656, rs2104286 and rs12722495 using the TaqMan allelic discrimination technology. The overall meta-analysis reached statistical significance when the three polymorphisms were tested for association with SSc, the limited subtype (lcSSc) and anti-centromere auto-antibodies (ACAs). However, no significant P-values were obtained when the ACA-positive patients were removed from the SSc and lcSSc groups, suggesting that these associations rely on ACA positivity. The strongest association signal with ACA production was detected for rs2104286 (P(FDR)=2.07 × 10(-4), odds ratio=1.30 (1.14-1.47)). The associations of rs11594656 and rs12722495 were lost after conditioning to rs2104286, and allelic combination tests did not evidence a combined effect, indicating that rs2104286 best described the association between IL2RA and ACA presence in SSc.
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Doenças Autoimunes/genética , Subunidade alfa de Receptor de Interleucina-2/genética , Escleroderma Sistêmico/genética , Adulto , Doenças Autoimunes/imunologia , Loci Gênicos , Humanos , Subunidade alfa de Receptor de Interleucina-2/imunologia , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Escleroderma Sistêmico/imunologiaRESUMO
Chronic obstructive pulmonary disease (COPD) is a moderate risk factor for venous thromboembolism (VTE), but neither the clinical presentation nor the outcome of VTE in COPD patients is well known. The clinical presentation of VTE, namely pulmonary embolism (PE) or deep venous thrombosis (DVT), and the outcome at 3 months (death, recurrent VTE or bleeding) were compared between 2,984 COPD patients and 25,936 non-COPD patients included in the RIETE (Registro Informatizado de la Enfermedad TromboEmbólica) registry. This ongoing international, multi-centre registry includes patients with proven symptomatic PE or DVT. PE was the more frequent VTE presentation in COPD patients (n = 1,761, 59%). PE presentation was more significantly associated with COPD patients than non-COPD patients (OR 1.64, 95% CI 1.49-1.80). During the 3-month follow-up, mortality (10.8% versus 7.6%), minor bleeding (4.5% versus 2.3%) or first VTE recurrences as PE (1.5% versus 1.1%) were significantly higher in COPD patients than in non-COPD patients. PE was the most common cause of death. COPD patients presented more frequently with PE than DVT. It may explain the worse prognosis of COPD patients, with a higher risk of death, bleeding or VTE recurrences as PE compared with non-COPD patients. Further therapeutic options are needed.
Assuntos
Doença Pulmonar Obstrutiva Crônica/mortalidade , Embolia Pulmonar/mortalidade , Tromboembolia Venosa/mortalidade , Trombose Venosa/mortalidade , Idoso , Idoso de 80 Anos ou mais , Feminino , Fibrinolíticos/uso terapêutico , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Prognóstico , Embolia Pulmonar/diagnóstico , Embolia Pulmonar/tratamento farmacológico , Sistema de Registros/estatística & dados numéricos , Fatores de Risco , Resultado do Tratamento , Filtros de Veia Cava , Tromboembolia Venosa/diagnóstico , Tromboembolia Venosa/terapia , Trombose Venosa/diagnóstico , Trombose Venosa/tratamento farmacológicoRESUMO
OBJECTIVES: The aim of this study was to evaluate the relevance of genetic variants of TLR5 (rs5744168) and TLR7 (rs179008) gene in systemic lupus erythematosus (SLE) in a Spanish population. MATERIAL AND METHODS: Our study population consisted of 752 SLE patients and 1107 healthy controls. All individual were of Spanish Caucasian origin. The TLR5 and TLR7 polymorphisms were genotyped using a PCR system with pre-developed TaqMan allelic discrimination assay. RESULTS: No statistically significant differences were observed when the allele and genotype distribution of TLR5 rs5744168 and TLR7 rs179008 polymorphisms was compared between SLE patients and healthy controls. A significant increase frequency in the CC genotype of the TLR5 rs5744168 polymorphism among SLE patients without nephritis was found (93% vs. 87% in SLE patients with nephritis, p=0.03, OR=2.11 95%CI 0.93-3.51). However, this difference did not reach statistical significance in the allele frequencies (p=0.08). CONCLUSION: These results suggest that the tested variations of TLR5 and TLR7 genes do not confer a relevant role in the susceptibility or severity to SLE in the Spanish population.
Assuntos
Predisposição Genética para Doença , Lúpus Eritematoso Sistêmico/genética , Polimorfismo de Nucleotídeo Único , Receptor 5 Toll-Like/genética , Receptor 7 Toll-Like/genética , Estudos de Casos e Controles , Humanos , Razão de Chances , População BrancaRESUMO
OBJECTIVES: To examine the clinical characteristics and outcomes of cancer patients with venous thromboembolism (VTE) in order to identify factors that place these patients at an increased risk for fatal pulmonary embolism (PE) or fatal bleeding. PATIENTS AND METHODS: Registro Informatizado de la Enfermedad Trombo Embólica (RIETE) is a prospective registry of consecutive patients with symptomatic, objectively confirmed, acute VTE. RESULTS: Up to January 2006, a total of 14 391 patients with symptomatic acute VTE were enrolled in RIETE, of whom 2945 (20%) had cancer. During the 3-month follow-up period the frequency of fatal PE in cancer patients was 2.6%, and that of fatal bleeding 1.0%. These frequencies were significantly higher than in VTE patients without cancer (1.4% and 0.3%, respectively). In patients with cancer, abnormal renal function, metastatic disease, recent major bleeding and recent immobility for >or= 4 days (42% of the 108 patients who died from PE or bleeding had recent immobility) were factors independently associated with an increased risk for both fatal PE and fatal bleeding. In addition, PE diagnosis on admission was an independent risk factor for fatal PE, while body weight < 60 kg was an independent risk factor for fatal bleeding. CONCLUSIONS: Both fatal PE and fatal bleeding are more common in cancer patients with VTE than in those patients without cancer. In cancer patients, abnormal renal function, metastatic disease, recent major bleeding and recent immobility for >or= 4 days are associated with an increased risk for both fatal PE and fatal bleeding.
Assuntos
Hemorragia/mortalidade , Neoplasias/mortalidade , Embolia Pulmonar/mortalidade , Trombose Venosa/mortalidade , Idoso , Feminino , Humanos , Imobilização , Nefropatias , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Neoplasias/complicações , Neoplasias/epidemiologia , Embolia Pulmonar/epidemiologia , Sistema de Registros , Fatores de Risco , Trombose Venosa/complicações , Trombose Venosa/epidemiologiaRESUMO
AIM: To study the influence of prednisone dose during the first month after systemic lupus erythematosus (SLE) diagnosis (prednisone-1) on glucocorticoid burden during the subsequent 11â months (prednisone-2-12). METHODS: 223 patients from the Registro Español de Lupus Eritematoso Sistémico inception cohort were studied. The cumulative dose of prednisone-1 and prednisone-2-12 were calculated and recoded into a four-level categorical variable: no prednisone, low dose (up to 7.5â mg/day), medium dose (up to 30â mg/day) and high dose (over 30â mg/day). The association between the cumulative prednisone-1 and prednisone-2-12 doses was tested. We analysed whether the four-level prednisone-1 categorical variable was an independent predictor of an average dose >7.5â mg/day of prednisone-2-12. Adjusting variables included age, immunosuppressives, antimalarials, methyl-prednisolone pulses, lupus nephritis and baseline SLE Disease Activity Index (SLEDAI). RESULTS: Within the first month, 113 patients (51%) did not receive any prednisone, 24 patients (11%) received average low doses, 46 patients (21%) received medium doses and 40 patients (18%) received high doses. There was a strong association between prednisone-1 and prednisone-2-12 dose categories (p<0.001). The cumulative prednisone-1 dose was directly associated with the cumulative prednisone-2-12 dose (p<0.001). Compared with patients on no prednisone, patients taking medium (adjusted OR 5.27, 95% CI 2.18 to 12.73) or high-dose prednisone-1 (adjusted OR 10.5, 95% CI 3.8 to 29.17) were more likely to receive prednisone-2-12 doses of >7.5â mg/day, while patients receiving low-dose prednisone-1 were not (adjusted OR 1.4, 95% CI 0. 0.38 to 5.2). If the analysis was restricted to the 158 patients with a baseline SLEDAI of ≥6, the model did not change. CONCLUSION: The dose of prednisone during the first month after the diagnosis of SLE is an independent predictor of prednisone burden during the following 11â months.
RESUMO
PURPOSE: To determine whether the features of the antiphospholipid syndrome (APS) are in any way influenced by the presence or absence of systemic lupus erythematosus (SLE). We followed up patients with 'primary' APS (PAPS) and APS secondary to SLE (APS plus SLE) with the objective of comparing laboratory and clinical events and of determining whether patients with PAPS would have evolution to SLE. PATIENTS AND METHODS: A total of 114 patients from 3 European referral centers were included in this study. Fifty-six had APS plus SLE and 58 had PAPS. Laboratory and clinical data were collected during an average 2-year period. RESULTS: Patients with PAPS and patients with APS plus SLE had similar clinical and laboratory profiles, with the exceptions of autoimmune hemolytic anemia, endocardial valve disease, neutropenia, and low C4 levels, all of which occurred more frequently in patients with APS plus SLE (p values: < 0.05, < 0.005, < 0.01, and < 0.001, respectively). On follow-up, 10 thrombotic episodes occurred in 10 patients, 8 of whom were receiving anticoagulant therapy. No patient with PAPS had either anti-DNA or anti-extractable nuclear antigen antibodies, and these patients had a significantly lower prevalence of antinuclear antibodies (41%) than patients with APS plus SLE (89%). CONCLUSIONS: Patients with APS plus SLE and PAPS have similar clinical profiles, although heart valve disease, hemolytic anemia, low C4 levels, and neutropenia seem to be more common in patients with APS plus SLE. Patients with APS may develop further thrombotic events despite anticoagulation therapy.
Assuntos
Síndrome Antifosfolipídica/complicações , Lúpus Eritematoso Sistêmico/complicações , Adulto , Anemia Hemolítica/complicações , Anticorpos Antinucleares/isolamento & purificação , Anticorpos Antifosfolipídeos/isolamento & purificação , Síndrome Antifosfolipídica/imunologia , Autoanticorpos/isolamento & purificação , Feminino , Doenças das Valvas Cardíacas/complicações , Humanos , Lúpus Eritematoso Sistêmico/imunologia , Masculino , Pessoa de Meia-Idade , Neutropenia/complicações , Estudos Prospectivos , Trombose/complicaçõesRESUMO
Road-deposited sediment (RDS) and its associated contaminant load play a critical role in degrading receiving water bodies. Few quantitative multi-element RDS studies exist, and there are none from Hawaii. This lack of baseline data combined with concerns with high concentrations of Pb and Cu in fish and enrichment of Cu, Pb and Zn in bed sediments from Manoa Stream, Hawaii, lead to a detailed characterization of RDSs in Manoa basin. Data for a total analysis of 23 elements using inductively coupled plasma atomic-emission spectrometry and instrumental neutron activation analysis and 16 elements using a 0.5 M HCl partial leach are presented for RDSs and background soils. Concentration data, comparisons with environmental guidelines, and concentration enrichment ratios (CERs) all indicate that RDS in Manoa has a significant degree of anthropogenic pollution. The most environmentally important elements were Pb, Sb and Zn. Concentrations of these elements, primarily vehicle contributed, compare favorably with those from other studies of RDS. The high mean concentration of Pb (151 mg/kg) compared to background soils (13 mg/kg) indicates remobilization of Pb previously stored in soils and transported to road surfaces by water erosion processes. The higher Pb CER(Total) in RDSs compared to bed sediments from Manoa Stream suggests a potential link via ubiquitous storm drains and subsequent dilution with less contaminated fluvial sediments. Data from the HCl leach also support Pb and Zn as having significant anthropogenic signals, and Cu having a moderate signal. These data indicate that RDSs in Manoa basin are generally contaminated with certain potentially toxic elements and the legacy of past use of leaded gasoline is still a concern in this urban drainage system.
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We report the case o a 40-year-old male patient with "primary antiphospholipid syndrome" who developed ischemic cerebral infarctions and renal microangiopathy with infarction. A review of the literature on renal involvement in the primary antiphospholipid syndrome disclosed the differences from the antiphospholipid syndrome in the systemic lupus erythematosus. We describe the evolution of the patient at eight years, and we emphasize the importance of the treatment with warfarin. Also, we review the pathophysiology of severe secondary arterial hypertension.
Assuntos
Síndrome Antifosfolipídica/complicações , Isquemia Encefálica/etiologia , Infarto Cerebral/etiologia , Infarto/etiologia , Rim/irrigação sanguínea , Adulto , Anticoagulantes/uso terapêutico , Síndrome Antifosfolipídica/tratamento farmacológico , Arteríolas/patologia , Disartria/etiologia , Fibrose , Humanos , Hipertensão/complicações , Hipertensão/fisiopatologia , Imageamento por Ressonância Magnética , Masculino , Fumar/efeitos adversos , Trombofilia/tratamento farmacológico , Trombofilia/etiologia , Varfarina/uso terapêuticoRESUMO
There are few studies addressing the frequency and etiology of anemia in progressive systemic sclerosis. Anemia is present in about 25% of these patients. Among the implicated causes are ferropenia, generally associated with gastrointestinal hemorrhage, and renal failure. In a considerable number of patients, the specific etiology of anemia remained unknown. We report a 59-year-old female with autoimmune hemolytic anemia and incomplete CREST syndrome. We emphasize the rarity of autoimmune hemolysis as a cause of anemia in systemic sclerosis, and we discuss its significance as indirectly supporting the possible autoimmune pathogenesis of that condition.
Assuntos
Anemia Hemolítica Autoimune/etiologia , Calcinose/complicações , Doença de Raynaud/complicações , Dermatopatias/complicações , Telangiectasia/complicações , Esôfago/fisiopatologia , Feminino , Dedos , Humanos , Pessoa de Meia-Idade , Esclerodermia Localizada/complicações , Síndrome , Dedos do PéRESUMO
The clinical and biological features of a series of 27 patients with the recently described primary antiphospholipid syndrome are reported. Most of them belonged to a cohort of 90 patients who were carriers of lupus anticoagulant, which had been detected in the systematic evaluation of prolonged activated partial thromboplastin times in our hospital. Since the diagnosis they underwent a prospective protocol of follow up, with a peak follow up period of 9 years. The mean age of the 27 patients was 40.8 years and there were virtually no differences between sexes. Venous thrombosis was the most common clinical finding (16 episodes in 14 of the 27 patients). The most prevalent laboratory findings were lupus anticoagulant and IgG anticardiolipin antibodies.
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Autoanticorpos/imunologia , Fatores de Coagulação Sanguínea/imunologia , Fosfolipídeos/imunologia , Aborto Espontâneo/sangue , Adolescente , Adulto , Fatores de Coagulação Sanguínea/análise , Feminino , Humanos , Inibidor de Coagulação do Lúpus , Masculino , Pessoa de Meia-Idade , Gravidez , Síndrome , Trombocitopenia/sangue , Trombose/sangueRESUMO
Exclusively penial lymphatic affections can be considered a highly infrequent occurrence. In the absence of an scrotal oedema, an "elephantiac" involvement with tumoral appearance in the penis, is indeed exceptional. A clinical case is briefly commented here. It refers to a patient with a significant sociopathy who presented a lymphedema confined to the penis in its maximum expression (elephantiasis verrucosa nostras).
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Elefantíase/patologia , Doenças do Pênis/patologia , Idoso , Humanos , MasculinoAssuntos
Arterite/terapia , Cuidados Paliativos , Dermatopatias/terapia , Transplante de Pele , Úlcera/terapia , Adulto , Feminino , HumanosRESUMO
BACKGROUND: The clinical significance of symptomatic isolated distal deep vein thrombosis (DVT) is uncertain. Consequently, this leads to important disparities in its management. OBJECTIVE: To examine the clinical history of isolated distal DVT and to compare it with that of proximal DVT. METHODS: Using data from the international, prospective, RIETE registry on patients with confirmed symptomatic venous thromboembolism (VTE), we compared the risk factors and 3-month outcome in patients with isolated distal DVT vs. proximal DVT. RESULTS: Eleven thousand and eighty-six patients with symptomatic DVT, but without pulmonary embolism, were included between 2001 and 2008; 1921 (17.3%) exhibited isolated distal DVT. Anticoagulant treatment was received by 89.1% (1680/1885) of isolated distal DVT and 91.8% (7911/8613) of proximal DVT patients for the entire follow-up period. Isolated distal DVTs were more associated with transient risk factors (i.e. recent travel, hospitalization, recent surgery), whereas proximal DVTs were more associated with chronic states (i.e. > or =75 years or with active cancer). At 3 months, major bleeding rate was lower in patients with isolated distal DVT (1.0% vs. 2.2%, P < 0.01), whereas VTE recurrence rate was equivalent (2.0% vs. 2.7%, P = 0.07). The mortality rate was lower in patients with isolated distal DVT (2.7% vs. 7.5%; P < 0.001); this was mainly due to a lower rate of non-VTE-related deaths (2.2% vs. 6.3%; P < 0.001). Active cancer was the main predictive factor of death in patients with isolated distal DVT. CONCLUSIONS: Proximal and isolated distal DVT patients differ in terms of risk factors and clinical outcomes, suggesting different populations. In the short term, the life expectancy of patients with isolated distal DVT depended chiefly on their cancer status.
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Trombose Venosa/epidemiologia , Distribuição por Idade , Idoso , Coleta de Dados , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias , Sistema de Registros , Fatores de Risco , Taxa de Sobrevida , Trombose Venosa/mortalidadeRESUMO
OBJECTIVE: To identify analytical and clinical variables that may improve the effectiveness of temporal artery biopsy (TAB) for the diagnosis of giant cell arteritis (GCA). MATERIALS AND METHODS: A retrospective study of TABs conducted between 1989 and 2007 at the 450-bed Hospital Parc Taulí, Sabadell. Demographic data, clinical manifestations, analytical data prior to the biopsy and final diagnoses were recorded, including only those cases in which these data were reflected in the clinical history. RESULTS: In this period, 278 TABs were conducted in 181 women (65.1%) and 97 men (mean age 74 years). Seventy-nine (28.4%) were positive (GCA+) and 199 (71.5%) negative (TAB-). The most frequent final diagnoses in the TAB- group were: polymyalgia rheumatica (PMR) (18.6%), giant cell arteritis plus negative TAB (GCA-) (13.6%), tension headache (7.5%), infection (7.5%), other vasculitis (7.5%), and neoplasm (6.0%). The GCA+ group was compared with the TAB- group, the GCA- group and the PMR group. In the multivariate analysis only headache (RR 3.6), jaw claudication (RR 2.9) and abnormal temporal artery on palpation (RR 2.5) revealed statistical differences between the GCA+ and TAB- groups. CONCLUSION: One third of the biopsies performed at our centre were positive for GCA. The clinical variables that best predicted a positive TAB in our series were headache, jaw claudication, and abnormal temporal artery on palpation.
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Biópsia , Arterite de Células Gigantes/patologia , Artérias Temporais/patologia , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Diagnóstico Diferencial , Feminino , Arterite de Células Gigantes/complicações , Hospitais Comunitários , Humanos , Masculino , Pessoa de Meia-Idade , Polimialgia Reumática/diagnóstico , Valor Preditivo dos Testes , Estudos Retrospectivos , Fatores de Risco , EspanhaRESUMO
The aim of this study was to determine the potential role of three IRF3 gene polymorphisms (rs2304204, rs7251 and rs2304207) with systemic lupus erythematosus (SLE). Our study population consisted of 610 patients with SLE and 730 healthy controls. All individual were of Spanish Caucasian origin. The IRF3 polymorphisms were genotyped using a PCR system with pre-developed TaqMan allelic discrimination assay. No statistically significant differences were found when allele and genotype distribution of rs2304204, rs7251 and rs2304207 polymorphisms were compared between patients with SLE and controls [overall P values: rs7251, P = 0.06; rs2304204, P = 0.26 and rs2304207, P = 0.36, by chi-squared test on a 3 x 2 contingency table. Overall allelic P values: rs7251, P = 0.8, OR (95%CI) = 1.03 (0.87-1.22); rs2304204, P = 0.2, OR (95%CI) = 1.12 (0.93-1.34) and rs2304207, P = 0.8, OR (95%CI) = 1.02 (0.82-1.26)]. In addition, no evidence of association with haplotypes and clinical features of SLE was found. Our data suggest that the IRF3 polymorphisms do not appear to play a major role in the susceptibility or severity of SLE in a Spanish population.
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Fator Regulador 3 de Interferon/genética , Lúpus Eritematoso Sistêmico , Polimorfismo Genético , Adolescente , Adulto , Feminino , Predisposição Genética para Doença , Genótipo , Humanos , Lúpus Eritematoso Sistêmico/genética , Lúpus Eritematoso Sistêmico/imunologia , Masculino , Pessoa de Meia-Idade , População Branca/genética , Adulto JovemRESUMO
BACKGROUND: Thrombocytopenia is a common haematological abnormality and no simple diagnostic test is available to diagnose thrombocytopenia pathogenesis. AIM: To evaluate sensitivity and specificity of reticulated platelets (RP) as a diagnostic test for thrombocytopenia with increased thrombopoietic activity. DESIGN: Prospective observational study in thrombocytopenic patients. METHODS: A direct, whole-blood, dual-labelling flow cytometric method was used. Direct, whole-blood double coverage was achieved using a monoclonal anti-glycoprotein (GP)-III antibody (CD61 PerCP) for platelet identification and thiazole orange (Retic-count) as platelet mARN stain. RESULTS: RP were measured in 101 thrombocytopenic patients and 104 non-thrombocytopenic controls. The mean RP percentage in 60 thrombocytopenic patients with no increased thrombopoietic activity was 7.5% (CI for 95%: 5.2-9.7) and RP absolute number was 3.2 x 10(9)/l (CI for 95%: 2.1-4.3). The mean RP percentage in 41 thrombocytopenic patients with increased thrombopoietic activity was 30.3% (CI for 95%: 25.1-35.5) and RP absolute number was 6.2 (CI for 95%: 4.8-7.7). The RP percentage cut-off for a diagnosis of thrombocytopenia with increased thrombopoietic activity was 11% [sensitivity 93%, specificity 85%, positive predictive value (PPV) 83%, negative predictive value (NPV) 95%]. CONCLUSION: RP measurement by flow cytometry, directly from whole-blood, is a useful screening test to differentiate between thrombocytopenia with high or low thrombopoietic activity. A RP percentage in excess of 11%, has a high sensitivity and good specificity for a diagnosis of thrombocytopenia with increased thrombopoietic activity.