RESUMEN
CONTEXT.: The American Board of Pathology (ABPath) publishes annual performance data for the anatomic pathology (AP) and clinical pathology (CP) board examinations, as well as for ABPath subspecialty examinations. Overall board pass rates for all AP and CP board examinees have increased during the past decade; however, no study has analyzed the board pass rates for pathology subspecialty examinations, and whether these follow the same trend. OBJECTIVE.: To evaluate ABPath subspecialty examination pass rates to assess the trend in certification. DESIGN.: We analyzed the total number of first-time test takers and board pass rates for 11 pathology subspecialties recognized by the ABPath from 2007 to 2021, acquired from annual reports published by the ABPath. We compared the pass rates in 5-year intervals (2007-2011, 2012-2016, 2017-2021) for each individual specialty. We also analyzed the pass rate of CP subspecialties compared with AP subspecialties. RESULTS.: The overall mean pass rate for ABPath subspecialty examinations during the previous 15 years was 89% (range, 78.9%-100%), with the overall pass rate being significantly higher in 2017-2021 (P = .02). The contemporary overall rate of passing was significantly higher for AP subspecialty examinations (P < .001) and was higher, though not significantly, for CP subspecialties (P = .13). There were significant differences between first-time test takers' mean pass rate (92.1%), repeat test takers' mean pass rate (54.5%), and the overall rate (P < .001). CONCLUSIONS.: Contemporary pathology subspecialty board examination pass rates are significantly higher than historic rates, possibly reflecting continuously improving and readily available preparatory materials.
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Patología Clínica , Consejos de Especialidades , Humanos , Estados Unidos , Becas , CertificaciónRESUMEN
BACKGROUND: Four-factor prothrombin complex concentrate 4F-PCC is the standard of care for warfarin reversal in patients with major bleed or requiring urgent surgery. Although the 4F-PCC dose is weight and international normalized ratio (INR) based, for practical purposes, a fixed-dose approach has been explored, especially for rapid reversal. We report our experience using two different fixed-dose 4F-PCC for warfarin reversal in patients presenting with intracranial hemorrhage (ICH). STUDY DESIGN AND METHODS: We completed a retrospective chart review comparing high (4000 units) versus low (2000 units) dose 4F-PCC by evaluating patient characteristics, laboratory data, and pre-and post-4F-PCC brain imaging. RESULTS: There was no significant difference between patient characteristics or INR correction (≤1.5) between the two groups. Eighty percent (12/15) of patients who received the low dose 4F-PCC had either improved or stable brain imaging as compared to 88% (14/16) of patients who received the high dose PCC. When the eight patients (4 from each arm of the study) who required neurosurgery were excluded, only two patients in each arm had worse imaging after 4F-PCC. CONCLUSION: There was no significant difference between the INR correction and the brain imaging changes in patients with an ICH who received either the high or the low fixed-dose 4F-PCC for warfarin reversal.
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Factores de Coagulación Sanguínea , Warfarina , Humanos , Warfarina/efectos adversos , Estudios Retrospectivos , Factores de Coagulación Sanguínea/farmacología , Factores de Coagulación Sanguínea/uso terapéutico , Relación Normalizada Internacional , Hemorragias Intracraneales/tratamiento farmacológico , Hemorragias Intracraneales/inducido químicamente , Factor IX , Anticoagulantes/efectos adversosRESUMEN
OBJECTIVES: Hypertriglyceridemia-induced acute pancreatitis (HTG-AP) accounts for 1 to 10% of pancreatitis cases, and is associated with a more severe clinical course. Therapeutic plasma exchange (TPE) is a potential treatment option for quickly lowering plasma triglycerides (TG). Current ASFA guidelines define HTG-AP as a Category III disorder, indicating the role of apheresis is not firmly established. Here, we examine clinical data regarding its effectiveness on morbidity and mortality in patients with HTG-AP presenting with severely elevated plasma triglycerides (>4000 mg/dl). METHODS: We retrospectively examined clinical data and outcomes from 67 consecutive episodes of HTG-AP over a 5-year period in which either medical management alone or medical management plus adjunct TPE was employed to reduce plasma triglycerides. RESULTS: 16/67 admissions involved TPE, initiated at a mean of 0.7 days from the time of presentation, while 51 received medical management alone. After only one TPE procedure, the mean TG values decreased from 4103 to 1045 mg/dl (a reduction of 74.7%), and those receiving TPE reached plasma TG < 1000 mg/dl 0.99 days faster than the medical group. One patient in the TPE group died. However, when excluding patients with hospital courses complicated by multiple organ dysfunction, there was no significant difference in mortality or hospital length of stay (LOS) between the groups. CONCLUSIONS: In uncomplicated cases of HTG-AP with an absence of multiorgan dysfunction, there is no significant benefit to either mortality or LOS when adding adjunct TPE to medical management, even when patients present with severely elevated levels of TG.
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Hipertrigliceridemia/complicaciones , Pancreatitis/etiología , Pancreatitis/terapia , Intercambio Plasmático , Triglicéridos/sangre , Adulto , Femenino , Humanos , Tiempo de Internación , Masculino , Persona de Mediana Edad , Pancreatitis/sangre , Intercambio Plasmático/efectos adversos , Estudios RetrospectivosRESUMEN
Hyperviscosity syndrome (HVS) is a life-threatening syndrome caused by high concentrations of large plasma proteins like IgM, rheumatoid factor, and other immune complexes, leading to increased blood viscosity and symptoms such as visual abnormalities, neurological impairment, bleeding diathesis, and thrombosis. While Waldenström's macroglobulinemia accounts for 80% to 90% of cases, HVS may develop in other clinical settings characterized by elevations in plasma proteins. Limited evidence currently exists describing the safety and efficacy of therapeutic plasma exchange (TPE) for the management of HVS secondary to non-neoplastic conditions. We report a case of recurrent HVS associated with juvenile rheumatoid arthritis and Felty syndrome that demonstrated improvement in clinical symptoms following initiation of TPE. These findings suggest that TPE may be utilized as an adjunct treatment option in patients with HVS secondary to autoimmune disorders.
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Artritis Juvenil/terapia , Intercambio Plasmático/métodos , Viscosidad , Adulto , Enfermedades Autoinmunes/inmunología , Enfermedades Autoinmunes/terapia , Síndrome de Felty/inmunología , Síndrome de Felty/terapia , Femenino , Hemorragia/terapia , Humanos , Leucopenia/complicaciones , Esplenomegalia/complicacionesRESUMEN
Novel immune-modulating anticancer drugs are being used with increasing frequency. With increased use, there are more frequent cases of toxicities caused by these drugs, termed immune-related adverse events (irAEs). We present a case in which we successfully treated a case of severe, steroid-refractory, nivolumab-induced myocarditis with therapeutic plasma exchange (TPE). Nivolumab is an immune checkpoint inhibitor (ICI) which blocks programmed death receptor-1 (PD-1). This blockade allows for enhanced T-cell function and increased anti-tumor response. The patient presented with signs and symptoms of heart failure and was found to have a significantly depressed cardiac ejection fraction. Over the course of her five TPE procedures, she improved clinically and was discharged home with improved left ventricular ejection function. This case suggests an emerging role of TPE in the management of severe ICI-induced toxicity, such as myocarditis.
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Inhibidores de Puntos de Control Inmunológico/toxicidad , Intercambio Plasmático/métodos , Abatacept , Corticoesteroides/uso terapéutico , Neoplasias de las Glándulas Suprarrenales/tratamiento farmacológico , Neoplasias de las Glándulas Suprarrenales/secundario , Anciano , Antineoplásicos/efectos adversos , Carcinoma de Células Renales/complicaciones , Carcinoma de Células Renales/tratamiento farmacológico , Femenino , Humanos , Sistema Inmunológico , Ácido Micofenólico/efectos adversos , Miocarditis/inducido químicamente , Neoplasias/tratamiento farmacológico , Nivolumab/efectos adversos , Receptor de Muerte Celular Programada 1/biosíntesis , Esteroides/químicaRESUMEN
OBJECTIVE: Stiff person syndrome (SPS) is commonly associated with antibodies directed against 65-kDa glutamic acid decarboxylase (GAD65). Therapeutic Plasma Exchange (TPE) has been used as an adjunct therapy in patients who do not respond well to conventional treatment, which includes immunosuppression therapies, anti-anxiety medications, muscle relaxants, anticonvulsants, and pain relievers. METHODS: We retrospectively analyzed the clinical data and outcomes of ten patients with the clinical diagnosis of anti-GAD65 positive SPS in which TPE was employed to improve symptoms refractory to conventional treatment during an eight-year period. RESULTS: TPE was initiated as complementary therapy in patients with worsening of symptoms characteristic of SPS. Six patients underwent chronic treatment with TPE following an initial course, of which the frequency of TPE was guided by the clinical response. Two patients only had transient improvements with further disease progression. Four patients developed a relapse of symptoms when the interval between procedures was increased. One of the four patients dependent on TPE had worsening of symptoms following complete cessation of TPE due to lack of insurance coverage. Four patients underwent only an acute hospitalized course of treatment with TPE; one demonstrated complete resolution of symptoms; one had a partial response; and two experienced no improvement. CONCLUSION: Our study supports previous reports that TPE may be beneficial for the management of patients with anti-GAD65 positive SPS, both for acute exacerbations and long-term maintenance, either as an adjunct therapy, or in lieu of treatment with disease modifying agents.
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Intercambio Plasmático , Síndrome de la Persona Rígida/terapia , Adulto , Anciano , Autoanticuerpos/sangre , Femenino , Glutamato Descarboxilasa/sangre , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Síndrome de la Persona Rígida/sangreRESUMEN
BACKGROUND: Intractable pruritus of cholestasis leads to significant morbidity. Therapeutic plasma exchange (TPE) has been shown to be an effective alternative in the setting of refractory pruritus associated with cholestatic liver disease based on several individual reports. Due to rarity of this approach to intractable pruritus, the literature is sparse and therefore TPE, as a treatment for refractory pruritus is currently not in the apheresis guidelines. We present three additional patients with severe intractable pruritus of cholestasis successfully treated with plasma exchange to add to the mounting literature showing this as an effective and safe adjunctive therapy. METHODS: Three patients underwent serial plasma exchange procedures to control pruritus. Frequency of plasma exchange was three times a week, with slow taper upon improvement of pruritus. Total bile acid levels were assessed before procedures. RESULTS: All three patients had an intractable pruritus with different underlying etiologies of cholestasis. All three patients showed significant improvement in pruritus, with none or minimal pruritus in one patient with primary biliary cirrhosis. Pre procedure bile acids levels were decreased initially, but showed rebound increase upon tapering of plasma exchange, without increased pruritus. No serious side effects or complications were observed. CONCLUSION: Our results in conjunction with the published literature show that severe and intractable pruritus associated with cholestasis could be successfully treated with TPE, irrespective of the underlying disease, and can be done safely.
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Colestasis/terapia , Intercambio Plasmático/métodos , Prurito/etiología , Ácidos y Sales Biliares/sangre , Colestasis/complicaciones , Humanos , Intercambio Plasmático/efectos adversos , Resultado del TratamientoRESUMEN
OBJECTIVES: Acute hypertriglyceridemia induced pancreatitis (HTP) presents with a more severe clinical course compared to other etiologies of pancreatitis. Therapeutic plasma exchange (TPE) is a potential treatment option for lowering plasma triglycerides and possibly decreasing morbidity and mortality. However, clinical data regarding its effectiveness are limited. METHODS: We retrospectively examined the clinical data and outcomes of 13 consecutive episodes of HTP in which TPE was employed to reduce plasma triglycerides during a 15-month period. RESULTS: The TPE was initiated at a median of 19 hours from the time of presentation. We performed 1.2-1.5 volume TPEs with 5% albumin as the replacement fluid. After only one TPE procedure, the mean plasma triglycerides values decreased from 2993 mg/dl to 487 mg/dl with a reduction of 84%. All 13 patients survived with a mean length of hospital stay of 9.5 days. There were no complications related to TPE. CONCLUSIONS: One TPE procedure is an effective method for reducing plasma triglycerides and possibly decreases the length of hospital stay in patients admitted with HTP.
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Hipertrigliceridemia/etiología , Pancreatitis/complicaciones , Pancreatitis/terapia , Intercambio Plasmático/métodos , Adolescente , Adulto , Demografía , Femenino , Humanos , Hipertrigliceridemia/sangre , Masculino , Persona de Mediana Edad , Pancreatitis/sangre , Triglicéridos/sangre , Adulto JovenRESUMEN
BACKGROUND: A four-factor prothrombin complex concentrate (4F-PCC) was recently licensed in the United States for urgent vitamin K antagonist (VKA) reversal based on two randomized clinical trials. These studies excluded patients at high risk of thrombosis; therefore, the risk of thrombotic complications in unselected patients remains a concern. STUDY DESIGN AND METHODS: This study retrospectively evaluated the incidence of thromboembolic events (TEEs) and death in patients who received 4F-PCC for VKA reversal. The study included 113 consecutive patients who were 18 years of age and older and were administered 4F-PCC for VKA reversal. The incidence of TEE and deaths was evaluated for up to 60 days after PCC administration or until the end of hospitalization, whichever came later. RESULTS: Seven (6.2%) patients developed TEEs and 17 (15%) patients died. PCC administration was probably related to TEE and subsequent death in two (1.8%) patients. Multivariate analysis revealed that a diagnosis of Factor V Leiden or antiphospholipid syndrome was predictive of TEE, and active malignancy was predictive of death. CONCLUSION: This study supports the safety of 4F-PCC for urgent VKA reversal even in unselected patients. The underlying type of hypercoagulable state and the dose of PCC may influence the incidence of TEE.
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4-Hidroxicumarinas/efectos adversos , Anticoagulantes/efectos adversos , Factores de Coagulación Sanguínea/uso terapéutico , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/tratamiento farmacológico , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/epidemiología , Indenos/efectos adversos , Tromboembolia/epidemiología , Vitamina K/antagonistas & inhibidores , Adulto , Anciano , Anciano de 80 o más Años , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/mortalidad , Femenino , Hospitales de Enseñanza/estadística & datos numéricos , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Práctica Profesional/estadística & datos numéricos , Estudios Retrospectivos , Texas/epidemiología , Tromboembolia/inducido químicamente , Tromboembolia/mortalidad , Resultado del Tratamiento , Vitamina K/efectos adversosRESUMEN
BACKGROUND: Little is known about how the resource utilization and costs of serologic work ups for positive antibody screens vary across subpopulations based on diagnosis, transfusion history, and serologic testing history. STUDY DESIGN AND METHODS: Detailed data were collected on patient demographics, diagnoses, transfusion history, history of known allo- and autoantibodies, and specific serologic tests performed for 6077 consecutive serologic work ups in 3608 antibody-positive patients between 2009 and 2011 at four US academic medical centers. Direct testing costs were also determined at each site for each serologic test performed to calculate total costs per work up and per patient over the duration of the study. RESULTS: The mean direct cost of serologic testing was $114 per work up and $195 per patient. The mean cost per patient was significantly higher for 12 of 19 diagnostic categories evaluated, including autoimmune hemolytic anemia (mean cost per patient, $1490; p < 0.001), hematologic malignancies ($640, p < 0.001), and transplant recipients ($462, p = 0.019). Patient transfusion and serologic testing characteristics associated with greatest increases in costs included history of a warm autoantibody ($626, p < 0.001) and more than five prior transfusions ($404, p < 0.001). CONCLUSION: Antibody-positive patients with complex diagnoses or transfusion histories require significantly more resources and incur greater cost to assess red blood cell antibody status.
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Anemia Hemolítica Autoinmune , Anticuerpos/sangre , Transfusión Sanguínea/economía , Costos de la Atención en Salud , Pruebas Serológicas/economía , Pruebas Serológicas/estadística & datos numéricos , Centros Médicos Académicos/economía , Adulto , Anemia Hemolítica Autoinmune/epidemiología , Anemia Hemolítica Autoinmune/prevención & control , Anemia Hemolítica Autoinmune/terapia , Ahorro de Costo , Femenino , Recursos en Salud/economía , Recursos en Salud/estadística & datos numéricos , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Estados Unidos/epidemiología , Revisión de Utilización de RecursosRESUMEN
Chronic simple hypertransfusion (every 3 to 4 weeks) effectively prevents secondary stroke in children with sickle cell anemia but leads to iron overload despite chelation therapy. Conventional red blood cell exchange (C-RBCx) has advantages over simple transfusion: no net iron gain and less frequent hospital visits. However, C-RBCx requires more red blood cell units, an apheresis instrument and skilled personnel; it is also more expensive. We developed a modified procedure where isovolemic hemodilution precedes RBCx (IHD-RBCx) to decrease RBC units required and to increase the interval between procedures. Twenty patients underwent IHD-RBCx over a period of 7 years. IHD-RBCx required 11% fewer RBC units and increased inter-procedure interval from 37 to 53 days compared to C-RBCx. The median number of annual procedures decreased from 9.8 to 7.0 per patient, resulting in estimated savings of more than $4.5 million over 10 years for 20 patients while providing improved care. Five patients have discontinued chelation therapy; three while on C-RBCx and two while on IHD-RBCx. No adverse events occurred related to the isovolemic hemodilution phase and no patients had recurrent stroke. IHD-RBCx is a safe, efficient, and cost effective therapy for secondary prevention of stroke in patients with sickle cell anemia.
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Anemia de Células Falciformes/sangre , Anemia de Células Falciformes/terapia , Transfusión de Eritrocitos , Hemodilución/métodos , Accidente Cerebrovascular/prevención & control , Adolescente , Adulto , Anemia de Células Falciformes/fisiopatología , Automatización de Laboratorios , Volumen Sanguíneo , Terapia por Quelación , Niño , Preescolar , Transfusión de Eritrocitos/efectos adversos , Femenino , Hemodilución/efectos adversos , Humanos , Masculino , Recurrencia , Estudios Retrospectivos , Prevención Secundaria/métodos , Adulto JovenRESUMEN
CaridianBCT currently does not recommend rinseback with its COBE Spectra cell separator during red blood cell (RBC) exchange procedure, as the machine's software does not take into account the "rinseback" when calculating the fraction of cells remaining (FCR, and therefore target hemoglobin S (HbS) value) and postexchange hematocrit (Hct). To our knowledge, no study has investigated the effect of rinseback on these laboratory values. Therefore, we performed pre- and postrinseback evaluations of FCR and Hct in 22 consecutive combined Isovolemic Hemodilution/Red blood cell (IHD-RBCx) exchange procedures in sickle cell anemia patients with stroke currently enrolled in our institution's chronic RBC exchange program. The pre- and-post rinseback values for HbS were 9.9 ± 4.66 and 10.7 ± 4.83 (P = 0.56) with corresponding FCRs of 22.6 ± 8.57 and 24.7 ± 8.75 (P = 0.44), and for Hct were 32.4 ± 2.93% and 32.2 ± 3.19% (P = 0.79), respectively. Since there was no significant difference in the "pre" and "post" values, we conclude that rinseback can be used during RBC exchange without any concern for significantly affecting Post Exchange HbS and Hct and possibly not waste 53 mL of precious red cell mass in the rinseback.
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Separación Celular/instrumentación , Transfusión de Eritrocitos , Recambio Total de Sangre , Hematócrito , Adulto , Anemia de Células Falciformes/terapia , Femenino , Humanos , Masculino , Accidente Cerebrovascular/terapiaRESUMEN
BACKGROUND: Plasma and platelets (PLTs) are often transfused to correct mild to moderately abnormal laboratory values. Our objective was to reduce unnecessary plasma and PLT transfusions to nonbleeding patients by prospective triage and education of end users in evidence-based hemostasis and transfusion medicine practices. STUDY DESIGN AND METHODS: Using the Parkland Memorial Hospital's transfusion service and admission database as the data source, this study comprises the comparison of transfusion data on plasma and PLT use between pre- (2000-2002) and posttriage (2003-2006) periods. Yearly transfusion and wastage data on red blood cells (RBCs), plasma, and PLTs and yearly hospital admissions, trauma visits, and surgical procedures were extracted retrospectively for the study. RESULTS: The study revealed that implementation of triage resulted in a significant reduction of plasma (60%) and PLT (25%) transfusions, saving more than $3,000,000 over 4 years. CONCLUSIONS: Prospective triage and evidence-based transfusion practice education reduced unnecessary plasma and PLT transfusions and health care costs.
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Transfusión de Componentes Sanguíneos/economía , Ahorro de Costo , Costos de la Atención en Salud/estadística & datos numéricos , Hospitales de Enseñanza/organización & administración , Plasma , Transfusión de Plaquetas/economía , Centros Traumatológicos/organización & administración , Triaje , Procedimientos Innecesarios/economía , Pruebas de Coagulación Sanguínea , Transfusión de Componentes Sanguíneos/estadística & datos numéricos , Medicina Basada en la Evidencia , Adhesión a Directriz/economía , Adhesión a Directriz/estadística & datos numéricos , Departamentos de Hospitales , Hospitales de Enseñanza/economía , Hospitales de Enseñanza/estadística & datos numéricos , Humanos , Admisión del Paciente/estadística & datos numéricos , Transfusión de Plaquetas/estadística & datos numéricos , Guías de Práctica Clínica como Asunto , Estudios Retrospectivos , Procedimientos Quirúrgicos Operativos/estadística & datos numéricos , Texas/epidemiología , Centros Traumatológicos/economía , Centros Traumatológicos/estadística & datos numéricos , Triaje/economía , Triaje/estadística & datos numéricos , Heridas y Lesiones/epidemiologíaRESUMEN
OBJECTIVE: To study the use of blood products including whole blood, for the management of obstetric hemorrhage requiring transfusion. METHODS: This was a population-based, observational study of all women receiving blood for hypovolemia because of hemorrhage at the Parkland obstetrics service between March 24, 2002, and June 12, 2006. Hypovolemia was diagnosed in women who sustained hemorrhages sufficient enough to provoke hemodynamic instability. RESULTS: A total of 66,369 women gave birth during the study period, and 1,540 (2.3%) received a blood transfusion. Six hundred fifty-nine (43%) received only whole blood, 593 (39%) received only packed red blood cells, and 288 (19%) received combinations of blood products, including thawed plasma, platelets, and cryoprecipitate. The number of units transfused was similar in the whole blood and packed red blood cell groups (mean 2 units) and higher in the combination group (mean 5.5 units). Complications attributable to hypovolemia were similar in frequency in the whole blood and packed red blood cells groups, including intensive care unit admission (1%), hypofibrinogenemia (0.3%), and adult respiratory syndrome (0.5% compared with .3%). Acute tubular necrosis was more common in the packed red blood cell group (2% compared with 0.3%, P<.001). All of these outcomes were increased in the combination transfusion group. There were three maternal deaths in the cohort, two in the combination group and one in the packed red blood cells group. CONCLUSION: The risk of acute tubular necrosis is significantly reduced in women receiving whole blood transfusion for hypovolemia due to obstetric hemorrhage. LEVEL OF EVIDENCE: III.
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Transfusión Sanguínea/métodos , Hipovolemia/terapia , Hemorragia Posparto/terapia , Adolescente , Adulto , Transfusión de Componentes Sanguíneos , Femenino , Fibrinógeno/análisis , Humanos , Hipovolemia/complicaciones , Hipovolemia/etiología , Unidades de Cuidados Intensivos , Necrosis Tubular Aguda/etiología , Embarazo , Síndrome de Dificultad Respiratoria/etiologíaRESUMEN
OBJECTIVES: To correlate optical density and percent inhibition of a two-step heparin-induced thrombocytopenia (HIT) antigen assay with thrombosis; the assay utilizes reaction inhibition characteristics of a high heparin concentration. PATIENTS AND METHODS: Patients with more than 50% decrease in platelet count or thrombocytopenia (<150 x 10(9)/L) after exposure to heparin, who had a positive two-step antigen assay [optical density (OD) >0.4 and >50 inhibition with high concentration of heparin] were included in the study. RESULTS: Forty of 94 HIT patients had thrombosis at diagnosis; 54/94 had isolated-HIT without thrombosis. Eight of the isolated-HIT patients developed thrombosis within the next 30 d; thus, a total of 48 patients had thrombosis at day 30. At diagnosis there was no significant difference in OD between HIT patients with thrombosis and those with isolated-HIT. However, OD was significantly higher in all patients with thrombosis (n = 48, 1.34 +/- 0.89), including isolated-HIT patients who later developed thrombosis within 30 d (n = 8, 1.84 +/- 0.64) as compared to isolated-HIT patients who did not develop thrombosis (0.96 +/- 0.75; P = 0.011 and P = 0.008). The Receiver Operative Characteristic Curve showed that OD >1.27 in the isolated-HIT group had a significantly higher chance of developing thrombosis by day 30. None of these groups showed significant difference in percent inhibition. Multivariate analysis showed a 2.8-fold increased risk of thrombosis in females. Similarly, thrombotic risk increased with age and OD values. CONCLUSION: Higher OD is associated with significant risk of subsequent thrombosis in patients with isolated-HIT; percent inhibition, however, was not predictive.