Benzodiazepines increase the likelihood of both infectious and thrombotic complications.

INTRODUCTION: Benzodiazepines (BZDs) modulate peripheral γ-amino-butyric acid type A on macrophages causing immunomodulation. They inhibit proinflammatory cytokines increasing infections. Prior studies have also shown that infections can increase thrombotic complications. We sought to examine this relationship in trauma patients. We hypothesized that the presence of BZDs on admission urine drug screen (UDS) would increase rates of both complications. METHODS: All patients submitted to the Pennsylvania Trauma Outcome Study database from 2003 to 2018 were queried. Those with a positive UDS for BZDs were analyzed. Infectious complications were defined as pneumonia, urinary tract infection, sepsis, wound, and soft tissue infection, and thrombotic complications were defined as presence of pulmonary embolism or deep vein thrombosis. Logistic regressions controlling for demographic and injury covariates assessed the adjusted impact of BZDs on infectious and thrombotic complications. RESULTS: A total of 3,393 patients (2.08%) had infectious complications, and 3,048 (1.87%) had thrombotic complications. Furthermore, 33,260 patients (20.4%) had a positive UDS for BZDs on admission. Univariate analysis showed that those positive for BZDs had higher rates of infectious (3.33% vs. 1.76%, p < 0.001) and thrombotic (2.84% vs. 1.62%, p < 0.001) complications. Multivariate analysis revealed that BZDs significantly increased the odds of infectious and thrombotic complications. Patients who tested positive for BZDs and subsequently developed infection had increased odds (adjusted odds ratio, 1.65; p < 0.001) of developing thrombotic complications. CONCLUSION: Trauma patients with a positive UDS for BZDs had higher odds of both infectious and thrombotic complications. Moreover, odds of thrombotic complications were higher in those with infections. LEVEL OF EVIDENCE: Epidemiological, level III.

Significance of urinary 11-dehydro-thromboxane B2 in age-related diseases: Focus on atherothrombosis.

Platelet activation plays a key role in atherogenesis and atherothrombosis. Biochemical evidence of increased platelet activation in vivo can be reliably obtained through non-invasive measurement of thromboxane metabolite (TXM) excretion. Persistent biosynthesis of TXA2 has been associated with several ageing-related diseases, including acute and chronic cardio-cerebrovascular diseases and cardiovascular risk factors, such as cigarette smoking, type 1 and type 2 diabetes mellitus, obesity, hypercholesterolemia, hyperhomocysteinemia, hypertension, chronic kidney disease, chronic inflammatory diseases. Given the systemic nature of TX excretion, involving predominantly platelet but also extraplatelet sources, urinary TXM may reflect either platelet cyclooxygenase-1 (COX-1)-dependent TX generation or COX-2-dependent biosynthesis by inflammatory cells and/or platelets, or a combination of the two, especially in clinical settings characterized by low-grade inflammation or enhanced platelet turnover. Although urinary 11-dehydro-TXB2 levels are largely suppressed with low-dose aspirin, incomplete TXM suppression by aspirin predicts the future risk of vascular events and death in high-risk patients and may identify individuals who might benefit from treatments that more effectively block in vivo TX production or activity. Several disease-modifying agents, including lifestyle intervention, antidiabetic drugs and antiplatelet agents besides aspirin have been shown to reduce TX biosynthesis. Taken together, these aspects may contribute to the development of promising mechanism-based therapeutic strategies to reduce the progression of atherothrombosis. We intended to critically review current knowledge on both the pathophysiological significance of urinary TXM excretion in clinical settings related to ageing and atherothrombosis, as well as its prognostic value as a biomarker of vascular events.

Isolated right ventricular thrombus in an adult patient with nephrotic syndrome: a case report.

BACKGROUND: Venous thrombosis in nephrotic syndrome is a well-described phenomenon. We report a case of an adult patient with an isolated thrombus in the right ventricle due to nephrotic syndrome, which was initially suspected to be a myxoma. CASE PRESENTATION: A 28-year-old white woman presented to our emergency department with signs of fluid overload. On further evaluation, a right ventricular mass was detected, which was resected and was found to be a thrombus. No other manifestations of venous thrombosis were found. Further evaluation of the patient revealed a nephrotic syndrome, which caused augmented coagulopathy. CONCLUSIONS: We present a case of a patient in whom a right ventricular mass was the first sign of a renally derived coagulopathy. To the best of our knowledge, this is the first report of an isolated thrombus in the right ventricle due to nephrotic syndrome in an adult. In cases of isolated cardiac thrombi in adults, a further search for renal disease might be helpful to reveal the underlying cause.

Discriminatory performance of positive urine hemoglobin for detection of significant hemolysis in patients with continuous-flow left ventricular assist devices.

BACKGROUND: Serum lactate dehydrogenase (LDH) is the standard measure for detection of hemolysis and thus surveillance for device thrombosis in patients on continuous-flow left ventricular assist device (CF-LVAD) support. Significant hemolysis has been defined as LDH ≥600 IU/L. However, LDH testing requires phlebotomy, precluding frequent home monitoring. Simple dipstick urinalysis (UA) for urine hemoglobin (U-Hb) overcomes this limitation. This study correlated U-Hb and LDH levels and evaluated the performance of UA for detection of significant hemolysis in patients with CF-LVADs. METHODS: U-Hb and LDH were measured concurrently 956 times in 221 patients with CF-LVADs. Statistics were computed to determine accuracy of UA in detecting LDH ≥600 IU/L, with a positive result being any detected U-Hb. All analyses were performed with and without excluding for 1) conditions associated with tissue damage, which are known to increase LDH, and 2) suspected or confirmed urinary tract infections or hematuria, which are known to cause hemoglobinuria for reasons other than hemolysis. RESULTS: Mean LDH for absent/mild/severe U-Hb was 360 IU/L/467 IU/L IU/L/777 IU/L without exclusions, 354 IU/L/444 IU/L IU/L/651 IU/L after excluding non-hemolytic LDH elevations, 370 IU/L/513 IU/L IU/L/1,357 IU/L after excluding urinary tract infections and hematuria, and 367 IU/L/470 IU/L IU/L/1,217 IU/L when both exclusions applied (all p < 0.001). Absent U-Hb had a negative predictive value for LDH ≥600 IU/L of >90% for all analyses. CONCLUSIONS: Serum LDH is significantly associated with U-Hb levels. Absence of U-Hb appears to efficiently exclude significant hemolysis in patients with CF-LVADs. Because it can be performed by patients at home, hemoglobinuria monitoring may enable more intense surveillance and earlier diagnosis of device thrombosis.

Indolic uremic solutes enhance procoagulant activity of red blood cells through phosphatidylserine exposure and microparticle release.

Increased accumulation of indolic uremic solutes in the blood of uremic patients contributes to the risk of thrombotic events. Red blood cells (RBCs), the most abundant blood cells in circulation, may be a privileged target of these solutes. However, the effect of uremic solutes indoxyl sulfate (IS) and indole-3-acetic acid (IAA) on procoagulant activity (PCA) of erythrocyte is unclear. Here, RBCs from healthy adults were treated with IS and IAA (mean and maximal concentrations reported in uremic patients). Phosphatidylserine (PS) exposure of RBCs and their microparticles (MPs) release were labeled with Alexa Fluor 488-lactadherin and detected by flow cytometer. Cytosolic Ca(2+) ([Ca(2+)]) with Fluo 3/AM was analyzed by flow cytometer. PCA was assessed by clotting time and purified coagulation complex assays. We found that PS exposure, MPs generation, and consequent PCA of RBCs at mean concentrations of IS and IAA enhanced and peaked in maximal uremic concentrations. Moreover, 128 nM lactadherin, a PS inhibitor, inhibited over 90% PCA of RBCs and RMPs. Eryptosis or damage, by indolic uremic solutes was due to, at least partially, the increase of cytosolic [Ca(2+)]. Our results suggest that RBC eryptosis in uremic solutes IS and IAA plays an important role in thrombus formation through releasing RMPs and exposing PS. Lactadherin acts as an efficient anticoagulant in this process.

The current and future landscape of urinary thromboxane testing to evaluate atherothrombotic risk.

Biomarker testing for efficacy of therapy is an accepted way for clinicians to individualize dosing to genetic and/or environmental factors that may be influencing a treatment regimen. Aspirin is used by nearly 43 million Americans on a regular basis to reduce risks associated with various atherothrombotic diseases. Despite its widespread use, many clinicians are unaware of the link between suboptimal response to aspirin therapy and increased risk for inferior clinical outcomes in several disease states, and biomarker testing for efficacy of aspirin therapy is not performed as routinely as efficacy testing in other therapeutic areas. This article reviews the clinical and laboratory aspects of determining whole-body thromboxane production, particularly as it pertains to efficacy assessment of aspirin responsiveness.

Point-of-care diagnostics for noncommunicable diseases using synthetic urinary biomarkers and paper microfluidics.

With noncommunicable diseases (NCDs) now constituting the majority of global mortality, there is a growing need for low-cost, noninvasive methods to diagnose and treat this class of diseases, especially in resource-limited settings. Molecular biomarkers combined with low-cost point-of-care assays constitute a potential solution for diagnosing NCDs, but the dearth of naturally occurring, predictive markers limits this approach. Here, we describe the design of exogenous agents that serve as synthetic biomarkers for NCDs by producing urinary signals that can be quantified by a companion paper test. These synthetic biomarkers are composed of nanoparticles conjugated to ligand-encoded reporters via protease-sensitive peptide substrates. Upon delivery, the nanoparticles passively target diseased sites, such as solid tumors or blood clots, where up-regulated proteases cleave the peptide substrates and release reporters that are cleared into urine. The reporters are engineered for detection by sandwich immunoassays, and we demonstrate their quantification directly from unmodified urine; furthermore, capture antibody specificity allows the probes to be multiplexed in vivo and quantified simultaneously by ELISA or paper lateral flow assay (LFA). We tailor synthetic biomarkers specific to colorectal cancer, a representative solid tumor, and thrombosis, a common cardiovascular disorder, and demonstrate urinary detection of these diseases in mouse models by paper diagnostic. Together, the LFA and injectable synthetic biomarkers, which could be tailored for multiple diseases, form a generalized diagnostic platform for NCDs that can be applied in almost any setting without expensive equipment or trained medical personnel.

Nanoparticles that sense thrombin activity as synthetic urinary biomarkers of thrombosis.

Thrombin is a serine protease and regulator of hemostasis that plays a critical role in the formation of obstructive blood clots, or thrombosis, that is a life-threatening condition associated with numerous diseases such as atherosclerosis and stroke. To detect thrombi in living animals, we design and conjugate thrombin-sensitive peptide substrates to the surface of nanoparticles. Following intravenous infusion, these "synthetic biomarkers" survey the host vasculature for coagulation and, in response to substrate cleavage by thrombin, release ligand-encoded reporters into the host urine. To detect the urinary reporters, we develop a companion 96-well immunoassay that utilizes antibodies to bind specifically to the ligands, thus capturing the reporters for quantification. Using a thromboplastin-induced mouse model of pulmonary embolism, we show that urinary biomarker levels differentiate between healthy and thrombotic states and correlate closely with the aggregate burden of clots formed in the lungs. Our results demonstrate that synthetic biomarkers can be engineered to sense vascular diseases remotely from the urine and may allow applications in point-of-care diagnostics.

Thromboxane A(2) generation, in the absence of platelet COX-1 activity, in patients with and without atherothrombotic myocardial infarction.

BACKGROUND: Aspirin's therapeutic action is via inhibition of platelet cyclooxygenase 1 (COX-1) thromboxane A2 (TxA2) production. The aim of this study was to evaluate TxA2 production, in the absence of platelet COX-1 activity, in coronary atherosclerotic heart disease patients with and without atherothrombotic myocardial infarction (MI). METHODS AND RESULTS: TxA2 production, in the absence of platelet COX-1 activity, was evaluated in 44 patients taking aspirin on 3 commercially available assays that detect metabolites of TxA2 in the urine. Two assays measure urine 11-dehydro-thromboxane B2 (TxB2) alone and 1 measures urine 11-dehydro-TxB2 plus 11-dehydro-2,3-dinor-TxB2. Platelet COX-1 inhibition was confirmed on <10% platelet aggregation in response to ≥1 mmol/L arachidonic acid. Median urine 11-dehydro-TxB2 was no different in those with and without a diagnosis of atherothrombotic MI (325 vs. 311 pg/mg creatinine, P=0.59 via polyclonal ELISA) and (312 vs. 244 pg/mg creatinine, P=0.11 via LC-MS/MS). Median urine 11-dehydro-TxB2 plus 11-dehydro-2,3-dinor-TxB2, however, was higher in those with vs. those without a diagnosis of atherothrombotic MI (1,035 vs. 606 pg/mg creatinine, P=0.03 via monoclonal ELISA). CONCLUSIONS: Differences in TxA2 production, in the absence of platelet COX-1 activity, between those with vs. without atherothrombotic MI were not observed when TxA2 generation was assessed on 11-dehydro-TxB2 production alone (polyclonal ELISA or LC-MS/MS), but differences were observed when TxA2 generation was assessed using 11-dehydro-TxB2 plus 11-dehydro-2,3-dinor-TxB2 (monoclonal ELISA). These findings highlight important differences between different commercially available assays for TxA2 generation and suggest that 11-dehydro-2,3-dinor-TxB2 may be critical to the biology of atherothrombosis.

Study of the mechanisms of aldosterone prothrombotic effect in rats.

INTRODUCTION: We investigated the role of primary haemostasis, fibrinolysis, nitric oxide (NO) and oxidative stress as well as mineralocorticoid receptors (MR) in acute aldosterone prothrombotic action. MATERIALS AND METHODS: Venous thrombosis was induced by stasis in Wistar rats. Aldosterone (ALDO; 10, 30, 100 µg/kg/h) was infused for 1 h. Eplerenone (EPL; 100 mg/kg, p.o.), a selective MR antagonist, was administered before ALDO infusion. Bleeding time (BT) and platelet adhesion to collagen were evaluated. The expression of nitric oxide synthase (NOS), NADPH oxidase, superoxide dismutase (SOD) and plasminogen activator inhibitor (PAI-1) was measured. NO, malonyl dialdehyde (MDA) and hydrogen peroxide (H(2)O(2)) plasma levels were assayed. RESULTS: Significant enhancement of venous thrombosis was observed after ALDO infusion. ALDO shortened BT and increased platelet adhesion. Marked increases were observed in PAI-1, NADPH oxidase and SOD mRNA levels. MDA and H(2)O(2) levels were augmented in ALDO-treated groups, and NOS expression and NO level were decreased. EPL reduced ALDO effects on thrombus formation, primary haemostasis, PAI-1 expression and MDA level. CONCLUSION: Short-term ALDO infusion enhances experimental venous thrombosis in the mechanism involving primary haemostasis, fibrinolysis, NO and oxidative stress-dependent pathways. The MR antagonist only partially diminished the ALDO effects, suggesting the involvement of additional mechanisms.

Pilot study of Alteplase (tissue plasminogen activator) for treatment of urinary clot retention in an in vitro model.

INTRODUCTION: The management of urinary clot retention and hematuria involves manual irrigation with sterile water or normal saline via a Foley catheter followed by continuous bladder irrigation. Irrigation may become difficult because of the formation of dense blood clots. Tissue plasminogen activator (t-PA/Alteplase) may be a useful pharmacological agent to improve the efficacy of manual irrigation of large, dense clots. The goal of the current study was to compare t-PA to sterile water for clot irrigation in an in vitro model. MATERIALS AND METHODS: In vitro models of clot retention were created using 500-cc urinary leg bags each filled with 80 cc of unpreserved whole blood from a healthy volunteer. Each model was incubated at 25 degrees C for 24 hours to allow clot formation. Four models each with 25 mL solution of t-PA at concentrations of 2, 1, 0.5, and 0.25 mg/mL were evaluated and compared to a control (25 mL sterile water). Models were instilled with solution (t-PA or control) and incubated for 30 minutes at 37 degrees C, and then irrigated with sterile water via 18F Foley by a blinded investigator. Three separate experiments were conducted, and statistical analysis was performed comparing various irrigation parameters. RESULTS: Clot evacuation with 25 mL of t-PA at a concentration of 2 mg/mL (50 mg) was significantly easier (p = 0.05) and faster (p < 0.05) than the sterile water control. The mean time for clot evacuation in this model was 2.7 minutes for t-PA solution 2 mg/mL versus 7.3 minutes for the control (p < 0.05). Compared to the control, irrigation with t-PA solution 2 mg/mL also required less irrigant (180 mL vs. 500 mL) (p < 0.05) for complete evacuation. There was a similar trend in efficacy for the lower doses of t-PA, but this was not statistically significant. CONCLUSION: In this in vitro study, a single 25 mL instillation of t-PA solution 2 mg/mL is significantly better than sterile water alone for clot evacuation. In vivo animal studies are pending.

Incidencia de trombosis intrastent en pacientes sometidos a intervencionismo coronario percutáneo en el Centro Cardiovascular Regional Ascardio / Incidence of stent thrombosis on patients undergoing percutaneous coronary intervention at the Centro Cardiovascular Regional Ascardio

Determinar la incidencia de trombosis intrastent en pacientes sometidos a intervencionismo coronario del Centro Cardiovascular Regional ASCARDIO, comparar incidencia de trombosis intrastent entre stent bare y stent medicado, determinar la inicidencia de trombosis en pacientes diábeticos. Estudio retrospectivo, descriptivo. Se revisaron 500 casos de intervencionismo coronario de los cuales se obtuvo información completa de 244 pacientes. Se tomó en cuenta la nueva clasificación de trombosis intrastent de la Academic Research Consortium. La incidencia de trombosis intrastent fue de 5,74% (14 pacientes) y la de trombosis definitiva de 2,87% (7 pacientes), no hubo diferencia significativa entre stent medicados; la incidencia de trombosis en diábeticos fue de 10% vs el 4,4% en los no diábeticos (P=0,104). En los pacientes con trombosis definitiva recibían significativamente más terapia dual antiplaquetaria que los probables o posibles (P=0,02). La longitud de los stents medicados trombosados fue significativamente mayor (23,22 ± 4,73 mm) que en los stents convencionales (15,89 ± 5,2 mm) (P=0,01) y el diámetro fue menor (2,82 ± 0,22mm) que en los convencionales (3,07 ± 0,18 mm)(P=0,05). También se encontro una mayor incidencia de trombosis en los stent medicados colocados en la coronaria derecha (P=0,02). La incidencia de trombosis definitivas en nuestro centro es mayor a la reportada; las trombosis intrastent tempranas y tardías no tienen diferencia significativa entre stents convencionales y los medicados. La longitud de los stents convencionales y los medicados trombosados fue significativamente mayor y de menor diámetro, comparado con los stent bare; la trombosis intrastent en diabéticos no mostro diferencia en relación al tipo de stent.

To determine the incidence of stent thrombosis on patients undergoing coronary interventions at the Centro Cardiovascular Regional Ascardio; and to compare the incidence of stent thrombosis between BMS and DES; and to determine the incidence of thrombosis on diabetic patients. This was a retrospective descriptive study. From 500 cases of coronary interventions, data was obtained on 244. The new classification of stent thrombosis by American Researche Consortium was applied. The incidence of thrombosis was 5.74% (14 patients) and for definite thrombosis was 2.87% (7 patients). there was no significant diferences between BMS and DES (P=1). The incidence of thrombosis on diabetic patients was 10% as compared to 4.4% on nondiabetic patients (P=0,104). We shown that patients with definite thrombosis received significantly more dual antiplatelet therapy than likely or possible thrombosis cases (P=0,02). The length of thrombosed DES was significantly higher (23.22 ± 4.73mm) tha BMS (15.89 ± 5.2mm, P=0.01)and the diameter was significantly lower (2.82 ± 0.22mm) than BMS (3.07 ± 0.18 mm, P=0.05). We also found a higher incidence of thrombosis for DES implanted on the right coronary artery (P=0.02). The incidence of definite thrombosis in our center was mildly higher than the reported incidence; early and late stent thrombosis showed no significant difference between BMS and DES; however the length of DES was significantly higher and less diameter tha BMS; dibetes was no significamtly higher on thrombosed stents.

Prothrombin fragment 1+2 in urine as an indicator of sustained coagulation activation after total hip arthroplasty.

PURPOSE: Prothrombin fragment 1+2 measured in spot urine (uF1+2) is an indicator of thrombin generation. We examined whether measured levels of uF1+2 can be used to differentiate between patients who do and do not acquire sustained coagulation activation after total hip arthroplasty (THA). METHODS: We performed two separate studies in patients undergoing THA. Study 1 was a prospective pilot study aiming to roughly estimate the extent of pre- and postoperative fluctuations in the uF1+2 concentration. Study 2 was a larger prospective cohort study aiming to verify the findings of Study 1 and to examine the association between the uF1+2 concentrations and risk of vascular thrombotic complications (VTC) or death. Finally, we sought to define a cut-off concentration value that could be used to identify patients with a sustained uF1+2 elevation after the first postoperative week. The urine samples were analysed by ELISA. In both studies thromboprophylaxis was used for at least 7 days after the operation. RESULTS: The operative trauma resulted in elevation of the uF1+2 level in all patients compared with the preoperative level and levels in the healthy volunteers. Ten out of 113 patients (8.8%) in the second study suffered VTC or death, assumed to be caused by a coagulation problem. Analysis of variance revealed the following statistically significant associations: pre- vs. postoperative log uF1+2 levels (P<0.0001), log uF1+2 levels comparing patients with and without events (P=0.004); and the individual log uF1+2 levels (P<0.0001). A cut-off value of uF1+2 concentration between 0.3 and 0.5 nmol/l had a sensitivity and a negative predictive value between100% and 90%, and specificity between 45% and 63% and overall accuracy between 50% and 65%. This value was obtained by the analysis of a receiver operating characteristic curve with the purpose of identifying patients with sustained coagulation activation on day 5 after operation. CONCLUSION: Our studies suggest that measured levels of uF1+2 can be potentially used to assess the individual risk of VTC after THA and to test for non-invasive detection of sustained coagulation activation.

Asymptomatic renal-vein thrombosis in adult nephrotic syndrome ultrasonography and urinary fibrin-fibrinogen products: a prospective study.

OBJECTIVES: The diagnosis of renal vein thrombosis (RVT), a frequent complication of adult nephrotic syndrome (NS), is generally made by means of invasive methods, i.e. renal venography, venous time of renal arteriography and, more recently, computed tomography (CT). We undertook a prospective study to evaluate the use of Doppler ultrasonography (DUS) and urinary fibrin-fibrinogen degradation products (FDPU) for the diagnosis of asymptomatic RVT. METHODS: Thirty-one adult NS with non proliferative glomerulonephritis were studied. Reference procedures [(selective renal arteriography (n = 18) and renal vein CT (n = 13)] were performed blindly within a few days (48 hours in 17 patients) of renal vein DUS (search for a lack of venous flow) and measurement of FDPU (5 micrograms/min) (in 24 patients). RESULTS: DUS was not interpretable in one patient and positive in nine. Of these 9 patients, RVT was detected by reference methods in only two (sensitivity: 1, specificity: 0.75; positive predictive value: 0.22; negative predictive value: 1). Increased FDPU was observed in 4 patients, 2 of whom had an RVT (sensitivity: 1, specificity: 0.9; positive predictive value: 0.5; negative predictive value: 1). CONCLUSION: We conclude that DUS and FDPU are helpful for screening of RVT in asymptomatic NS patients; their negativity allow further radiological investigations to be avoided while positive results must be confirmed by reference methods.

[Immunoreactive urinary thromboxane B2 in experimental mesenteric thrombosis in dogs]. / Tromboxano B2 urinario inmunorreactivo en trombosis mesentérica experimental en perros.

Thromboxane B2 (TxB2) the stable metabolite of thromboxane A2 may be released as a response to ischemia. With the aim of investigating its role as an early diagnostic test in mesenteric thrombosis, immunoreactive TxB2 was measured in urine aliquotes in six sham operated dogs, nine dogs subjected to superior mesenteric artery ligation, and twelve dogs with superior mesenteric vein ligation. One hour urine volumes were collected before surgery and during the eight hours after the experimental procedures, and urinary osmolarities were also determined in each sample. Basal TxB2 levels were comparable in all groups. Although all groups showed a significant and rapid (one hour) increase in TxB2 as a response to surgery, in the controls it returned to normal after six hours, whereas in the rest a continuously increased production persisted throughout the study period. There was no difference in t-test comparisons depending on the sort of thrombosis. In spite of the urinary dilution induced during the study, a persistent increase in TxB2 excretion was found. We conclude that urinary TxB2 levels could prove useful in the early diagnosis of mesenteric ischemia.

Characterization of urinary proteinase inhibitors with segments of amino acids sequences identical to sequences of pancreatic secretory trypsin inhibitor.

1. Slow migrating proteinase inhibitors were isolated from pathological human urine. 2. The N-terminal amino acid sequence including 23 amino acids was identical to the one in pancreatic secretory trypsin inhibitor. 3. The slow migrating proteinase inhibitors occurred in 3 forms with different electrophoretic mobility. 4. Time of flight mass spectrometry showed that the Mw of one of the forms was 6241 while the Mw of another form was 5923. 5. The Ki of complexes with trypsin was determined to be 1 x 10(-10) M, with chymotrypsin and plasmin Ki was 1 x 10(-7) M. Elastase, kallikrein and thrombin were not inhibited.

Enhanced urinary immunoreactive thromboxane in neonatal necrotizing enterocolitis. A diagnostic indicator of thrombotic activity.

Urinary thromboxane B2 levels increased threefold to 20-fold in infants with neonatal necrotizing enterocolitis compared with healthy infants and infants with benign causes of heme-positive stools. Increased urinary thromboxane B2 levels were detected coincidently with the initial signs of necrotizing enterocolitis, and values paralleled the course of the illness. Infants with serious illnesses other than necrotizing enterocolitis had increased urinary thromboxane B2 levels but with lower values than those of infants with necrotizing enterocolitis. Indomethacin therapy appeared to reduce urinary thromboxane B2 levels and reduce their usefulness as a marker of illness. Another product of platelet activation, beta-thromboglobulin, was increased in the urine of infants with necrotizing enterocolitis. Decreased platelet counts in infants with necrotizing enterocolitis correlated inversely with urinary thromboxane. Results of beta-thromboglobulin and platelet studies are consistent with the concept that platelet consumption due to ischemic thrombosis was the source of enhanced thromboxane excretion.

Case report. Unilateral renal vein thrombosis without proteinuria.

Unilateral renal vein thrombosis occurred in a patient who was found to have an adenocarcinoma and who had previously been subjected to trauma. Proteinuria was absent throughout the patient's entire clinical course, despite its well known association with renal vein thrombosis. However, other findings suggestive of renal vein thrombosis, including back pain and tenderness, hematuria and an enlarged kidney were present. It is clear that proteinuria need not be the only signal to occasion a search for renal thrombosis. This case probably constitutes the second report of absent proteinuria when thrombus forms within renal vein.