Neutrophil-mediated oxidative stress and albumin structural damage predict COVID-19-associated mortality.

Human serum albumin (HSA) is the frontline antioxidant protein in blood with established anti-inflammatory and anticoagulation functions. Here, we report that COVID-19-induced oxidative stress inflicts structural damages to HSA and is linked with mortality outcome in critically ill patients. We recruited 39 patients who were followed up for a median of 12.5 days (1-35 days), among them 23 had died. Analyzing blood samples from patients and healthy individuals (n=11), we provide evidence that neutrophils are major sources of oxidative stress in blood and that hydrogen peroxide is highly accumulated in plasmas of non-survivors. We then analyzed electron paramagnetic resonance spectra of spin-labeled fatty acids (SLFAs) bound with HSA in whole blood of control, survivor, and non-survivor subjects (n=10-11). Non-survivors' HSA showed dramatically reduced protein packing order parameter, faster SLFA correlational rotational time, and smaller S/W ratio (strong-binding/weak-binding sites within HSA), all reflecting remarkably fluid protein microenvironments. Following loading/unloading of 16-DSA, we show that the transport function of HSA may be impaired in severe patients. Stratified at the means, Kaplan-Meier survival analysis indicated that lower values of S/W ratio and accumulated H2O2 in plasma significantly predicted in-hospital mortality (S/W≤0.15, 81.8% (18/22) vs. S/W>0.15, 18.2% (4/22), p=0.023; plasma [H2O2]>8.6 µM, 65.2% (15/23) vs. 34.8% (8/23), p=0.043). When we combined these two parameters as the ratio ((S/W)/[H2O2]) to derive a risk score, the resultant risk score lower than the mean (<0.019) predicted mortality with high fidelity (95.5% (21/22) vs. 4.5% (1/22), log-rank χ2=12.1, p=4.9×10-4). The derived parameters may provide a surrogate marker to assess new candidates for COVID-19 treatments targeting HSA replacements and/or oxidative stress.

Removal of Protein-Bound Uremic Toxins by Liposome-Supported Peritoneal Dialysis.

Background:Protein-bound uremic toxins (PBUTs) are poorly cleared by peritoneal dialysis (PD). This study aimed to enhance PBUT removal in PD by adding a binder to the peritoneal dialysate and to evaluate the feasibility and efficacy of liposome-supported PD (LSPD) to increase the removal of PBUTs compared with albumin PD.Methods:Removal of p-cresyl sulfate (PCS), indoxyl sulfate (IS), and indole-3-acetic acid (3-IAA) was first evaluated in an in vitro PD model using artificial plasma preloaded with test solutes. Male Sprague-Dawley rats (n = 24) were then subjected to 5/6 nephrectomy and fed for 16 weeks to establish end-stage renal failure, after which they were treated with either conventional glucose-based PD, albumin-based PD, or liposome-based PD. Removal of PBUTs and small water-soluble solutes was determined during a 6-hour PD dwell.Results:In vitro experiments showed that adding albumin as a toxin binder to the dialysate markedly increased the removal of PCS, IS, and 3-IAA compared with the control. The uptake capacity of liposomes was comparable with that of albumin for PCS and 3-IAA, though slightly inferior for IS. In vivo PD in uremic rats demonstrated that LSPD resulted in higher intraperitoneal concentrations and more total mass removal for PBUTs than the conventional glucose-based PD, which was comparable with albumin PD.Conclusions:Supplementing conventional glucose-based PD solutions with a binder could efficiently increase the removal of PBUTs. This preliminary study suggested that LSPD may be a promising alternative to albumin PD for increasing PBUT removal in the development of next-generation PD solutions for PD patients.

Altered antibacterial activity of Curcumin in the presence of serum albumin, plasma and whole blood.

Antibacterial effect is one of the major therapeutic activities of plant-derived Curcumin. This work evaluated the effect of serum albumin, human plasma, and whole blood on the in vitro activity of Curcumin against eight clinical bacterial isolates by standard broth microdilution and plate-counting methods. Toxicological effects of Curcumin towards human red blood cells (RBCs) and peripheral blood mononuclear cells (PBMCs) were also investigated. Curcumin exhibited weak activity against gram-negative bacteria, except Escherichia coli and Shigella flexneri were susceptible and was most active against gram-positive bacteria: Staphylococcus aureus, Streptococcus pyogenes and Enterococcus faecalis. The antibacterial activity was impaired in the presence of bovine serum albumin (BSA), human plasma and whole blood. Curcumin was not toxic to PBMCs and RBCs at 200µg/mL. Furthermore, Curcumin showed synergistic activity in combination with antibiotics: Ciprofloxacin, Gentamicin, Vancomycin and Amikacin against Staphylococcus aureus. This study demonstrated that the interaction of Curcumin with plasma proteins diminishes its in vitro antibacterial activity. Curcumin derivatives with reduced affinity for plasma protein may improve the bioavailability and antibacterial activities.

Neprilysin Inhibits Coagulation through Proteolytic Inactivation of Fibrinogen.

Neprilysin (NEP) is an endogenous protease that degrades a wide range of peptides including amyloid beta (Aß), the main pathological component of Alzheimer's disease (AD). We have engineered NEP as a potential therapeutic for AD but found in pre-clinical safety testing that this variant increased prothrombin time (PT) and activated partial thromboplastin time (APTT). The objective of the current study was to investigate the effect of wild type NEP and the engineered variant on coagulation and define the mechanism by which this effect is mediated. PT and APTT were measured in cynomolgus monkeys and rats dosed with a human serum albumin fusion with an engineered variant of NEP (HSA-NEPv) as well as in control plasma spiked with wild type or variant enzyme. The coagulation factor targeted by NEP was determined using in vitro prothrombinase, calibrated automated thrombogram (CAT) and fibrin formation assays as well as N-terminal sequencing of fibrinogen treated with the enzyme. We demonstrate that HSA-NEP wild type and HSA-NEPv unexpectedly impaired coagulation, increasing PT and APTT in plasma samples and abolishing fibrin formation from fibrinogen. This effect was mediated through cleavage of the N-termini of the Aα- and Bß-chains of fibrinogen thereby significantly impairing initiation of fibrin formation by thrombin. Fibrinogen has therefore been identified for the first time as a substrate for NEP wild type suggesting that the enzyme may have a role in regulating fibrin formation. Reductions in NEP levels observed in AD and cerebral amyloid angiopathy may contribute to neurovascular degeneration observed in these conditions.

Transforming the treatment for hemophilia B patients: update on the clinical development of recombinant fusion protein linking recombinant coagulation factor IX with recombinant albumin (rIX-FP).

Recombinant fusion protein linking recombinant coagulation factor IX with recombinant albumin (rIX-FP; Idelvion®(†)) is an innovative new treatment designed to extend the half-life of factor IX (FIX) and ease the burden of care for hemophilia B patients. The rIX-FP clinical development program - PROLONG-9FP - is in its advanced phases, with pivotal studies in previously treated adults, adolescents, and pediatrics now completed. Across all age groups studied, rIX-FP has demonstrated a markedly improved pharmacokinetic profile compared with plasma-derived and recombinant FIX treatments, with a 30-40% higher incremental recovery, an approximately 5-fold longer half-life, a lower clearance, and a greater area under the curve. rIX-FP has been very well tolerated with an excellent safety profile. In the pivotal studies, there have been no reports of FIX inhibitors or antidrug antibodies, and few treatment-related adverse events have been observed. Prophylactic regimens of rIX-FP administered once weekly to once every 14 days have been highly effective. When used for surgical prophylaxis, a single infusion of rIX-FP has been sufficient to maintain hemostasis, even during major orthopedic surgery. An ongoing study is now enrolling previously untreated patients and evaluating the possibility of extending the dosing interval to every 21 days. There is little doubt that rIX-FP will transform the treatment of hemophilia B.

Advanced Glycation End Products (AGE) Potently Induce Autophagy through Activation of RAF Protein Kinase and Nuclear Factor κB (NF-κB).

Advanced glycation end products (AGE) accumulate in diabetic patients and aging people because of high amounts of three- or four-carbon sugars derived from glucose, thereby causing multiple consequences, including inflammation, apoptosis, obesity, and age-related disorders. It is important to understand the mechanism of AGE-mediated signaling leading to the activation of autophagy (self-eating) that might result in obesity. We detected AGE as one of the potent inducers of autophagy compared with doxorubicin and TNF. AGE-mediated autophagy is inhibited by suppression of PI3K and potentiated by the autophagosome maturation blocker bafilomycin. It increases autophagy in different cell types, and that correlates with the expression of its receptor, receptor for AGE. LC3B, the marker for autophagosomes, is shown to increase upon AGE stimulation. AGE-mediated autophagy is partially suppressed by inhibitor of NF-κB, PKC, or ERK alone and significantly in combination. AGE increases sterol regulatory element binding protein activity, which leads to an increase in lipogenesis. Although AGE-mediated lipogenesis is affected by autophagy inhibitors, AGE-mediated autophagy is not influenced by lipogenesis inhibitors, suggesting that the turnover of lipid droplets overcomes the autophagic clearance. For the first time, we provide data showing that AGE induces several cell signaling cascades, like NF-κB, PKC, ERK, and MAPK, that are involved in autophagy and simultaneously help with the accumulation of lipid droplets that are not cleared effectively by autophagy, therefore causing obesity.

A Phase III Study of Balugrastim Versus Pegfilgrastim in Breast Cancer Patients Receiving Chemotherapy With Doxorubicin and Docetaxel.

OBJECTIVES: This study aimed to evaluate the efficacy and safety of once-per-cycle balugrastim versus pegfilgrastim for neutrophil support in breast cancer patients receiving myelosuppressive chemotherapy. METHODS: Breast cancer patients (n = 256) were randomized to 40 or 50 mg of subcutaneous balugrastim or 6 mg of pegfilgrastim ≈24 hours after chemotherapy (60 mg/m(2) doxorubicin and 75 mg/m(2) docetaxel, every 21 days for up to 4 cycles). The primary efficacy parameter was the duration of severe neutropenia (DSN) in cycle 1. Secondary parameters included DSN (cycles 2-4), absolute neutrophil count (ANC) nadir, febrile neutropenia rates, and time to ANC recovery (cycles 1-4). Safety, pharmacokinetics, and immunogenicity were assessed. RESULTS: Mean cycle 1 DSN was 1.0 day with 40 mg of balugrastim, 1.3 with 50 mg of balugrastim, and 1.2 with pegfilgrastim (upper limit of 95% confidence intervals for between-group DSN differences was <1.0 day for both balugrastim doses versus pegfilgrastim). Between-group efficacy parameters were comparable except for time to ANC recovery in cycle 1 (40 mg of balugrastim, 2.0 days; 50 mg of balugrastim, 2.1; pegfilgrastim, 2.6). Median terminal elimination half-life was ≈37 hours for 40 mg of balugrastim, ≈36 for 50 mg of balugrastim, and ≈45 for pegfilgrastim. Antibody response to balugrastim was low and transient, with no neutralizing effect. CONCLUSION: Once-per-cycle balugrastim is not inferior to pegfilgrastim in reducing cycle 1 DSN in breast cancer patients receiving chemotherapy; both drugs have comparable safety profiles. IMPLICATIONS FOR PRACTICE: This paper provides efficacy and safety data for a new, once-per-cycle granulocyte colony-stimulating factor, balugrastim, for the prevention of chemotherapy-induced neutropenia in patients with breast cancer receiving myelosuppressive chemotherapy. In this phase III trial, balugrastim was shown to be not inferior to pegfilgrastim in the duration of severe neutropenia in cycle 1 of doxorubicin/docetaxel chemotherapy, and the safety profiles of the two agents were similar. Once-per-cycle balugrastim is a safe and effective alternative to pegfilgrastim for hematopoietic support in patients with breast cancer receiving myelosuppressive chemotherapy associated with a greater than 20% risk of developing febrile neutropenia.

New insights into in vitro amyloidogenic properties of human serum albumin suggest considerations for therapeutic precautions.

Amyloid aggregates display striking features of detergent stability and self-seeding. Human serum albumin (HSA), a preferred drug-carrier molecule, can also aggregate in vitro. So far, key amyloid properties of stability against ionic detergents and self-seeding, are unclear for HSA aggregates. Precautions against amyloid contamination would be required if HSA aggregates were self-seeding. Here, we show that HSA aggregates display detergent sarkosyl stability and have self-seeding potential. HSA dimer is preferable for clinical applications due to its longer retention in circulation and lesser oedema owing to its larger molecular size. Here, HSA was homodimerized via free cysteine-34, without any potentially immunogenic cross-linkers that are usually pre-requisite for homodimerization. Alike the monomer, HSA dimers also aggregated as amyloid, necessitating precautions while using for therapeutics.

Comparison of 6% hydroxyethyl starch and 5% albumin for volume replacement therapy in patients undergoing cystectomy (CHART): study protocol for a randomized controlled trial.

BACKGROUND: The use of artificial colloids is currently controversial, especially in Central Europe Several studies demonstrated a worse outcome in intensive care unit patients with the use of hydroxyethyl starch. This recently even led to a drug warning about use of hydroxyethyl starch products in patients admitted to the intensive care unit. The data on hydroxyethyl starch in non-critically ill patients are insufficient to support perioperative use. METHODS/DESIGN: We are conducting a single-center, open-label, randomized, comparative trial with two parallel patient groups to compare human albumin 5% (test drug) with hydroxyethyl starch 6% 130/0.4 (comparator). The primary endpoint is cystatin C ratio, calculated as the ratio of the cystatin value at day 90 after surgery relative to the preoperative value. Secondary objectives are inter alia the evaluation of the influence of human albumin and hydroxyethyl starch on further laboratory chemical and clinical parameters, glycocalyx shedding, intensive care unit and hospital stay and acute kidney injury as defined by RIFLE criteria (risk of renal dysfunction, injury to the kidney, failure of kidney function, loss of kidney function, and end-stage kidney disease) criteria. DISCUSSION: There is a general lack of evidence on the relative safety and effects of hydroxyethyl starch compared with human albumin for volume replacement in a perioperative setting. Previously conducted studies of surgical patients in which researchers have compared different hydroxyethyl starch products included too few patients to properly evaluate clinical important outcomes such as renal function. In the present study in a high-risk patient population undergoing a major surgical intervention, we will determine if perioperative fluid replacement with human albumin 5% will have a long-term advantage over a third-generation hydroxyethyl starch 130/0.4 on the progression of renal dysfunction until 90 days after surgery. TRIAL REGISTRATION: EudraCT number 2010-018343-34. Registered on 11 January 2010.

Characterization of Nanoparticle Tracking Analysis for Quantification and Sizing of Submicron Particles of Therapeutic Proteins.

Submicron particles may play important roles in therapeutic protein product quality, stability, and adverse effects in patients. However, quantitation of these particles has been challenging. Nanoparticle tracking analysis (NTA) is capable of both sizing and counting submicron particles. We investigated the effects of product and instrument parameters on NTA results for nanoparticle standards and therapeutic protein samples. To obtain proper particle size distributions, complete tracking numbers of at least 200 and 400 were required for latex nanobeads and protein nanoparticles, respectively. In addition, when set at suboptimal values, the minimum expected particle size parameter led to inaccurate sizing and counting for all particles types investigated. A syringe pump allowed for higher sampling volumes, and results were reproducible for nanoparticle sizing and counts at flow rates ≤7 µL/min. Finally, because therapeutic protein products are being formulated at relatively high protein concentrations, we investigated the effects of protein concentration on nanoparticle characterization. With high protein concentrations, nanoparticle sizing was not affected, whereas particle concentrations were significantly reduced. Linear relationships between particle count and dilution factor were obtained when a high protein concentration formulation was diluted into particle-free solutions at the same protein concentrations, but not when dilutions were made into buffer.

First-in-human, phase I/IIa dose-escalation and safety study of balugrastim in breast cancer patients receiving myelosuppressive chemotherapy.

PURPOSE: To evaluate safety of balugrastim, a recombinant human serum albumin and granulocyte colony-stimulating factor (G-CSF), administered over a range of therapeutic doses in women with breast cancer receiving doxorubicin plus docetaxel chemotherapy. METHODS: The phase I, sequential dose-escalation first segment compared subcutaneous balugrastim 50, 150, 300, and 450 µg/kg during chemotherapy cycles 0-2. The randomized (2:2:1), open-label, phase IIa second segment compared balugrastim 300 or 450 µg/kg with pegfilgrastim 6 mg during chemotherapy cycles 1 and 2. RESULTS: In the phase I segment, balugrastim was escalated to 450 µg/kg in 13 patients without dose-limiting toxicity. Three (9.7 %) of the 31 adverse events (AEs) reported in nine patients were grade 3 (agranulocytosis, vomiting, hypertension); none was grade 4. In the open-label phase IIa segment (N = 51), the majority of the 64 AEs reported in 31 (75.6 %) balugrastim-treated patients were grade 1 (59.4 %), with 39.1 % grade 2, 1.6 % grade 3 (one AE of vomiting), and none grade 4. Of the 16 AEs reported in seven (70.0 %) pegfilgrastim-treated patients, 87.5 % were grade 1, 6.3 % were grade 2, 6.3 % were grade 3 (one AE of thrombocytopenia), and none were grade 4. Overall, there were six bone pain AEs reported, one in the balugrastim 300 µg/kg group and five in the balugrastim 450 µg/kg group. No AEs in either study necessitated treatment interruption/discontinuation. The incidence and duration of grade 3-4 neutropenia were similar between balugrastim- and pegfilgrastim-treated patients. CONCLUSIONS: Balugrastim was well tolerated in this small population of breast cancer patients.

Crystalloids and colloids in critical patient resuscitation.

Fluid resuscitation is essential for the survival of critically ill patients in shock, regardless of the origin of shock. A number of crystalloids and colloids (synthetic and natural) are currently available, and there is strong controversy regarding which type of fluid should be administered and the potential adverse effects associated with the use of these products, especially the development of renal failure requiring renal replacement therapy. Recently, several clinical trials and metaanalyses have suggested the use of hydroxyethyl starch (130/0.4) to be associated with an increased risk of death and kidney failure, and data have been obtained showing clinical benefit with the use of crystalloids that contain a lesser concentration of sodium and chlorine than normal saline. This new information has increased uncertainty among clinicians regarding which type of fluid should be used. We therefore have conducted a review of the literature with a view to developing practical recommendations on the use of fluids in the resuscitation phase in critically ill adults.

Combined local blood-brain barrier opening and systemic methotrexate for the treatment of brain tumors.

Despite aggressive therapy, existing treatments offer poor prognosis for glioblastoma multiforme patients, in part due to poor penetration of most drugs across the blood-brain barrier (BBB). We propose a minimal-invasive combined treatment approach consisting of local BBB disruption in the tumor in parallel to systemic drug administration. Local BBB disruption is obtained by convection-enhanced delivery of a novel BBB disruption agent, enabling efficient/targeted delivery of the systemically administered drug by the tumors own vasculature. Various human serum albumin (HSA) analogs were synthesized and screened for BBB disruption efficacy in custom in vitro systems. The candidate analogs were then delivered into naïve rat brains by convection-enhanced delivery and screened for maximal BBB disruption and minimal brain toxicity. These studies found a noncationized/neutralized analog, ethylamine (EA)-HSA, to be the optimal BBB-opening agent. Immunocytochemical studies suggested that BBB disruption by EA-HSA may be explained by alterations in occludin expression. Finally, an efficacy study in rats bearing intracranial gliomas was performed. The rats were treated by convection-enhanced delivery of EA-HSA in parallel to systemic administration of Methotrexate, showing significant antineoplastic effects of the combined approached reflected in suppressed tumor growth and significantly (~x3) prolonged survival.

Efficacy, effectiveness and safety of long-acting granulocyte colony-stimulating factors for prophylaxis of chemotherapy-induced neutropenia in patients with cancer: a systematic review.

PURPOSE: Pegfilgrastim was introduced over a decade ago. Other long-acting granulocyte colony-stimulating factors (G-CSFs) have recently been developed. We systematically reviewed the efficacy, effectiveness and safety of neutropenia prophylaxis with long-acting G-CSFs in cancer patients receiving chemotherapy. METHODS: We performed a systematic literature search of the MEDLINE, EMBASE and Cochrane Library databases, and abstracts from key congresses. Studies of long-acting G-CSFs for prophylaxis of chemotherapy-induced neutropenia (CIN) and febrile neutropenia (FN) were identified by two independent reviewers. Abstracts and full texts were assessed for final inclusion; risk of bias was evaluated using the Cochrane's tool. Effectiveness and safety results were extracted according to study type and G-CSF used. RESULTS: Of the 839 articles identified, 41 articles representing different studies met the eligibility criteria. In five randomised controlled trials, 11 clinical trials and 17 observational studies across several tumour types and chemotherapy regimens, pegfilgrastim was used alone or compared with daily G-CSF, no G-CSF, no upfront pegfilgrastim or placebo. Studies generally reported lower incidence of CIN (4/7 studies), FN (11/14 studies), hospitalisations (9/13 studies), antibiotic use (6/7 studies) and adverse events (2/5 studies) with pegfilgrastim than filgrastim, no upfront pegfilgrastim or no G-CSF. Eight studies evaluated other long-acting G-CSFs; most (5/8) were compared to pegfilgrastim and involved patients with breast cancer receiving docetaxel-based therapy. Efficacy and safety profiles of balugrastim and lipegfilgrastim were comparable to pegfilgrastim in phase 3 studies. Efficacy and safety of other long-acting G-CSFs were mixed. CONCLUSIONS: Pegfilgrastim reduced the incidence of FN and CIN compared with no prophylaxis. Most studies showed better efficacy and effectiveness for pegfilgrastim than filgrastim. Efficacy and safety profiles of lipegfilgrastim and balugrastim were similar to pegfilgrastim.

Effect of intraoperative human albumin on early graft function in renal transplantation.

Adequate intravascular volume maintenance is essential to ensure early graft function during renal transplantation. Various recommendations on optimum fluid therapy are based, at best, on sparse evidence, and that too only from observational studies. This prospective randomized controlled study was done to evaluate the effect of 20% human albumin on the early graft function in living donor renal transplantation. Eighty patients undergoing renal transplantation were randomly assigned to one of the intraoperative fluid regimens, 0.9% normal saline with 20% human albumin (albumin group) or 0.9% normal saline alone (saline group), after confirming the exclusion criteria. Intravenous fluid infusion was given to keep central venous pressure (CVP) between 12 to 15 mm Hg. The statistical package of social sciences, SPSS version 12, was used for statistical analysis. The intraoperative fluid volume infused [albumin group--3381±1021.2 vs. saline group--3487±978.5 (mL)] to maintain target CVP was comparable between the two groups (P value>0.05). Statistically, no significant difference was found between the two groups in terms of post transplant serum creatinine [day one; 2.76±1.0 vs. 2.58±0.94, day three; 1.48±0.53 vs. 1.43±0.71, day seven; 1.42±0.6 vs. 1.42±0.53 (mg/dL)] and urine output [day one; 13122.5±5767.8 vs. 13909.4±5324.7, day three; 9233.9±3267.4 vs. 9250±4794.2, day seven; 7517.6±3043.6 vs. 6921.4±3170 (mL)] (P value>0.05). Postoperative change in body weight [1.89±3.82 vs. 2.48±3.89 (kg)], tissue edema (10% vs. 7.5%), and pulmonary edema (2.5% vs. 5%) did not differ significantly (P>0.05). Twenty percent human albumin given intraoperatively, as a volume expander, does not improve early graft function in living donor renal transplantation. It should be used selectively rather than as a routine protocol.

Immunotoxicity assessment of rice-derived recombinant human serum albumin using human peripheral blood mononuclear cells.

Human serum albumin (HSA) is extensively used in clinics to treat a variety of diseases, such as hypoproteinemia, hemorrhagic shock, serious burn injuries, cirrhotic ascites and fetal erythroblastosis. To address supply shortages and high safety risks from limited human donors, we recently developed recombinant technology to produce HSA from rice endosperm. To assess the risk potential of HSA derived from Oryza sativa (OsrHSA) before a First-in-human (FIH) trial, we compared OsrHSA and plasma-derived HSA (pHSA), evaluating the potential for an immune reaction and toxicity using human peripheral blood mononuclear cells (PBMCs). The results indicated that neither OsrHSA nor pHSA stimulated T cell proliferation at 1x and 5x dosages. We also found no significant differences in the profiles of the CD4(+) and CD8(+) T cell subsets between OsrHSA- and pHSA-treated cells. Furthermore, the results showed that there were no significant differences between OsrHSA and pHSA in the production of cytokines such as interferon-gamma (IFN-γ), tumor necrosis factor-alpha (TNF-α), interleukin (IL)-10 and IL-4. Our results demonstrated that OsrHSA has equivalent immunotoxicity to pHSA when using the PBMC model. Moreover, this ex vivo system could provide an alternative approach to predict potential risks in novel biopharmaceutical development.

[Current role of albumin in critical care]. / Papel actual de la albúmina en cuidados críticos.

The use of colloids in fluid therapy has been, and still continues to be a controversial topic, particularly when referring to the critical patient. The choice of the fluid that needs to be administered depends on several factors, many of which are theoretical, and continue being an object of debate. The interest in the clinical use of the albumin has emerged again, immediately after recent publications in the search of the most suitable colloid. It is the most abundant protein in the plasma, being responsible for 80% of the oncotic pressure. It regulates the balance between the intra- and extra-vascular volumes. Recent multicenter studies question the supposed lack of safety that was previously assigned to it. Furthermore, in vitro studies demonstrate other important actions besides oncotic, for example neutralization of free radicals, and exogenous (drugs) and endogenous substances (bile pigments, cholesterol). Being aware of these secondary properties of albumin, and evaluating the pathophysiology of the critical patient (in particular, sepsis), to maintain plasma albumin levels within the normal range, could be of great importance. Based on the most recent publications, the aim of this review is to briefly analyze the pathophysiology of albumin, as well as to discuss its possible indications in the critical patient.

Near-fatal anaphylaxis caused by human serum albumin in fibrinogen and erythrocyte concentrates.

A 40-year-old man developed anaphylactic shock during surgical replacement of a prolapsed mitral valve during general anaesthesia and an attenuated reaction (Grade 2), three days later during a blood transfusion. Human serum albumin, a component of the fibrinogen concentrate used postoperatively with the erythrocyte concentrate, was identified as the trigger, confirmed by positive skin prick and intradermal tests. Any anaphylaxis during the peri-operative period should cause the clinician to perform allergy tests for identification of the culprit drug and, sometimes, culprit additive. Testing of human serum albumin, acting as hidden allergen, should be included, especially where there has been a blood transfusion.