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T Bosch

Publications and source records attributed to T Bosch.

At least 19 recordsLinked to original sources
PubMed2001

[Invassive infections caused by Group A streptococci: clinical characteristics and microbiological analyses in 31 cases].

BACKGROUND: In the last two decades an increase in the incidence of invassive Streptococcus pyogenes infections has been reported in several countries. The objective of this study was to determine the clinical features of these infections in our hospital. METHODS: Retrospective study (1995-1998) of patients admitted at Son Dureta Hospital, Palma de Mallorca, Spain, who had S. pyogenes recovered from blood, sterile fluids or soft tissues. Patients clinical records were reviewed and bacterial isolates characterized. RESULTS: A total of 31 patients with invassive infections caused by S. pyogenes were identified. The annual incidence rates (number of episodes/1,000 admissions) were: 0.13 (1995), 0.20 (1996), 0.27 (1997), and 0.23 (1998). The mean age of patients was 41 years. Seventy four percent of patients had some underlying disease, and the most relevant conditions included: diabetes mellitus (5), parenteral drug abuse (4), chronic alcoholism (3), chronic liver disease (3) and infection with the human immunodeficiency virus (3). The most common portal of entry was the skin (78%). The initial clinical presenting form was cellulitis (39%). Necrotizing fasciitis, septic shock, and streptococcal toxic shock syndrome (STSS) were observed in 9.6%, 12.9%, and 6.4% of patients, respectively. The mortality rate was 16.1%. The phenotypic characterization of S. pyogenes isolates indicated that most isolates were of mucoid type and identified 11 different M serotypes, M1 being the most common. CONCLUSIONS: A steady increase in the incidence of invassive infections caused by S. pyogenes was observed since 1995 to 1997 in our hospital. Patients with certain underlying conditions are more susceptible to acquire these infections. The worst outcome of these infections corresponded to elderly patients, those with septic shock or STSS. Most strains responsible for these infections were encapsulated and the M1 serotype predominated.

Adolescent↗
PubMed2001

Direct adsorption of lipoproteins from whole blood by DALI apheresis: technique and effects.

Low-density lipoprotein (LDL) apheresis can drastically reduce atherogenic lipoproteins in coronary patients in whom LDL and lipoprotein (a) (Lp[a]) cannot be sufficiently reduced by conservative therapy. LDL and Lp(a) adsorption by polyacrylate/polyacrylamide (DALI) is the simplest procedure for clinical LDL apheresis to date. DALI was first applied in patients in 1994 and introduced into clinical routine in 1996. It is the first LDL-hemoperfusion system, i.e., it adsorbs LDL and Lp(a) directly from whole blood. This markedly simplifies the extracorporeal circuit, the handling of the system, and reduces significantly staff time and, especially at higher blood flow rates, treatment time. Its features are high selectivity and capacity of lipoprotein removal (maximum about 8 g low-density lipoprotein cholesterol per session). Using citrate anticoagulation, good biocompatibility is evidenced by the lack of cell losses, hemolysis, thrombotic events, and complement activation. Some clotting factors of the intrinsic system are also adsorbed. There is significant bradykinin activation that, however, does not cause problems in most patients if angiotensin converting enzyme inhibitor medication is avoided. In a first long-term study, 93% of sessions were uneventful. Major side effects were citrate-induced paresthesias (1.3%) and hypotension (0.8%). To date, more than 25,000 DALI sessions have been performed all over the world.

Adsorption↗
PubMed2001

High-efficiency DALI apheresis using 1,250 ml adsorbers in a hypercholesterolemic obese patient: a case report.

Direct adsorption of lipoproteins (DALI) apheresis is the first method for direct adsorption of lipoproteins from whole blood and is therefore an easy and rapid procedure. The majority of patients reaches >60% acute low-density lipoprotein cholesterol (LDL-C) reduction using either the DALI 750 or 1000 configuration. However, in patients with extremely high LDL-C levels or very large blood volumes, these configurations may lead to suboptimal results. The current study was performed to test the safety and efficacy of DALI 1250. In a severely obese patient (185 cm, 133 kg, blood volume 7.2 L, LDL-C 239 mg/dl), 11 L of blood (1.53-fold patient blood volume) was processed at a flow rate of 80 ml/min in 2.5 h; a combined heparin-plus-citrate anticoagulation regimen was used. Commercially available DALI 1250 and DALI hardware and disposables were manufactured by Fresenius HemoCare Adsorber Technology, St. Wendel, Germany. Twenty weekly sessions were performed. Clinically and technically, the apheresis sessions were completely uneventful. As compared to DALI 1000 (n = 4 sessions), the reduction rates by DALI 1250 (n = 20) improved for LDL-C (from 52% to 66%), lipoprotein (a) (Lp[a]) (53% vs. 66%), and fibrinogen (11% vs. 16%). There was a slight increase in high-density lipoprotein cholesterol (HDL-C) loss (20% vs. 24%). Moreover, the absolute amount of LDL-C removed per session increased from 5.06 g to 5.94 g. Laboratory safety parameters remained within the normal range, the anticoagulation was well controlled, and the pressure gradients over the adsorber remained constant. In this case report, DALI 1250 was perfectly safe and significantly increased the efficacy of LDL-C and Lp(a) elimination compared to standard DALI. Thus, this high-efficiency version of DALI may be used in patients with extremely high LDL-C levels and/or large blood volumes.

Adsorption↗
PubMed2001

Improvement of hemorheology by DALI apheresis: acute effects on plasma viscosity and erythrocyte aggregation in hypercholesterolemic patients.

Plasma viscosity (PV) and erythrocyte aggregation (EA) are determinants of microcirculation, especially under the compromised hemodynamic conditions resulting from atherosclerosis. Direct adsorption of lipoproteins (DALI) apheresis is the first method for direct adsorption of lipoproteins; it drastically reduces low-density lipoprotein (LDL)-cholesterol and lipoprotein (a) (Lp[a]), and may therefore improve PV and EA. The current study was performed to test the effect of DALI on hemorheology. Six hypercholesterolemic patients who had been on regular LDL apheresis for at least several months were treated on a weekly or biweekly basis, on average 5 times each by DALI. Before and after each session, PV was measured by a capillary tube plasma viscosimeter and EA by rotational aggregometry. Single DALI sessions (n = 31) acutely decreased PV from 1.18 +/- 0.04 to 1.06 +/- 0.3 mPa (-10%) while EA improved from 22.8 +/- 4.4 to 13.3 +/- 4.5 (arbitrary units) (-42%). LDL-cholesterol, Lp(a), and very-low-density lipoprotein (VLDL)-cholesterol were effectively reduced while the decrease of triglycerides and fibrinogen was only moderate. DALI apheresis exerted an acute positive effect on blood hemorheology which may have beneficial effects on microcirculation. This hypothesis is in accordance with the clinical observation that in some patients, improvement of angina and/or exercise tolerance can be observed after only a few DALI sessions where changes of coronary stenoses cannot be expected yet.

Adsorption↗
PubMed2001

Background and indications for protein A-based extracorporeal immunoadsorption.

Protein A (SPA), a major cell wall component of Staphylococcus aureus, has occupied numerous investigators from its discovery in the late fifties. Its availability and avid binding to human immunoglobulins have led to extensive usage for diagnostic and research purposes. Today, SPA-based extracorporeal immunoadsorption relies on two rather different systems, namely, SPA-silica (Prosorba), and SPA-Sepharose (Immunosorba). Both systems are approved by the Food and Drug Administration for the core indications of rheumatoid arthritis and idiopathic thrombocytopenic purpura (SPA-silica) or hemophilia with inhibitors (SPA-Sepharose). Off label indications include immune disorders with a conceivable connection between autoantibody titers and disease activity, like forms of glomerulonephritis, systemic lupus erythematodes, myasthenia, and the Guillain-Barré syndrome as well as alloantibody formation in the context of e.g., transplantation. This review summarizes historical developments and important properties of SPA. Indications for extracorporeal therapy are discussed on the basis of available information and personal experience.

Adsorption↗
PubMed2001

Therapeutic plasma exchange in the intensive care setting.

The potential to treat life-threatening conditions with therapeutic plasma exchange (TPE) is limited to a few situations. In severe pulmonary hemorrhage as a complication of several immune disorders (e.g., antiglomerular basement membrane antibody disease, Wegener's granulomatosus, lupus erythematosus), TPE should only be considered after conventional measures (mostly pulses of methylprednisolone) have been applied. Idiopathic familial and nonfamilial thrombotic thrombocytopenic purpura as well as the subset of the hemolytic uremic syndrome not associated with diarrhea are clear indications for TPE using fresh frozen plasma as replacement fluid. Patients with myasthenic crisis will also benefit from TPE and will improve within 1 day. Acute pancreatitis as a complication of the chylomicronemia syndrome has a poor prognosis and should be treated with TPE without any delay. In the case of drug overdose or intoxication, the efficiency of TPE to remove the offending drug is usually overestimated. In this situation, TPE is useful only when the plasma protein binding of the substance is high (>80%) and the volume of distribution is low (<0.2 L/kg body weight). TPE is not without risks and hazards (e.g., vascular access, bleeding, allergy), which should also be considered when discussing this extracorporeal therapy in otherwise refractory clinical conditions.

Hematologic Diseases↗
PubMed2001

Extracorporeal plasma treatment in primary and recurrent focal segmental glomerular sclerosis: a review.

This review summarizes the state of the art of apheresis in focal segmental sclerosing glomerulonephritis (FSGS) based on the current literature. FSGS is a major cause of nephrotic syndrome and renal insufficiency and has a high tendency to recur after renal transplantation. In many instances, treatment with steroids and/or immunosuppressive agents is without effect. Therapeutic plasma exchange (as well as immunoadsorption in some instances) was performed in primary (pFSGS) and recurrent (rFSGS) FSGS. Proteinuria could be improved and renal function was stabilized in 58% of rFSGS adults, in 74% of rFSGS children, and in 44% of pFSGS in adults. Treatment was successful if implemented early, i.e., in the stage of minimal change glomerulopathy before significant sclerosis had developed. This approach will probably be realistic only in the regular follow-up after transplantation. Furthermore, some patients with full-blown pFSGS were treated successfully in a prophylactic indication immediately prior to transplantation which decreased the incidence of recurrence to 26% in treated patients versus 54% in controls. Due to the uncontrolled study design and small patient cohorts in most trials, the major disadvantage of the reports currently available on the use of apheresis in FSGS is their low level of evidence from which the previous conclusions had to be drawn. Large prospective, controlled and randomized clinical trials are urgently needed for recommendations based on high-level evidence.

Adult↗
PubMed2001

Extracorporeal plasma treatment in thrombotic thrombocytopenic purpura and hemolytic uremic syndrome: a review.

This review summarizes the state of the art of apheresis in hemolytic uremic syndrome (HUS) and in thrombotic thrombocytopenic purpura (TTP). Both entities are characterized by thrombotic microangiopathy, hemolytic anemia, and thrombocytopenia. While HUS often presents with renal insufficiency, cerebral involvement is more common in TTP. Recently, in TTP, a primary or secondary lack of activity of a von Willebrand factor (vWF) degrading enzyme was made responsible for the presence of unusually large vWF multimers causing platelet aggregation and thrombus formation in the microvasculature. In contrast, in familial HUS, a factor H deficiency with uninhibited complement activation seems to play a role. Therapeutic plasma exchange (TPE) using fresh frozen plasma or cryosupernatant as the substitution fluid is indicated in acute TTP and atypical HUS without antecedent diarrhea. As a rule, it will show good effectiveness, especially in the former entity. HUS in pregnancy should be treated by instant delivery whereas postpartum HUS may resolve using protracted courses of TPE. In contrast, in thrombotic microangiopathy after bone marrow transplantation as well as in HUS due to cancer, mitomycin C, or after renal transplantation, TPE is of questionable value and indicated only as a last resort treatment.

Extracorporeal Circulation↗
PubMed2000

DALI apheresis in hyperlipidemic patients: biocompatibility, efficacy, and selectivity of direct adsorption of lipoproteins from whole blood.

Recently, the first apheresis technique for direct adsorption of low-density lipoprotein (LDL) and lipoprotein(a) [Lp(a)] from whole blood (DALI) was developed that does not require a prior plasma separation. That markedly simplifies the extracorporeal circuit. The aim of the present study was to test the acute biocompatibility, efficacy, and selectivity of DALI apheresis. In a prospective clinical study, 6 hypercholesterolemic patients suffering from angiographically proven atherosclerosis were treated 4 times each by DALI. 1.3 patient blood volumes were treated per session at blood flow rates of 60-80 ml/min using 750 or 1,000 ml of polyacrylate/polyacrylamide adsorber gel. The anticoagulation consisted of an initial heparin bolus followed by a citrate infusion. The sessions were clinically essentially uneventful. Mean corrected reductions of lipoproteins amounted to 65% for LDL-cholesterol, 54% for Lp(a), 28% for triglycerides, 1% for HDL-cholesterol, and 8% for fibrinogen. The selectivity of lipoprotein removal was high. Cell counts remained virtually unchanged and no signs of hemolysis or clotting were detected. Cell activation parameters elastase, beta-thromboglobulin, interleukin-1beta, and IL-6 showed no significant increase. Complement activation was negligible. There was significant, but clinically asymptomatic, bradykinin activation in the adsorber with mean maxima of 12,000 pg/ml in the efferent line at 1,000 ml of treated blood volume. In conclusion, DALI proved to be safe, selective, and efficient for the adsorption of LDL-C and Lp(a), which simplifies substantially the extracorporeal therapy in hypercholesterolemic patients.

Acrylic Resins↗
PubMed2000

Ex vivo biocompatibility of avidin-agarose: a new device for direct adsorption of biotinylated antibodies from human whole blood.

Radioimmunotherapy using radiolabeled antitumor antibodies (RAA) is limited by the toxicity of unbound antibodies in the circulation. Removal of excessive antibodies by affinity-adsorption could therefore allow the administration of increased dosages of RAA while decreasing their adverse effects. Recently, avidin-agarose (AA) minicolumns were used in animal experiments for the removal of biotinylated antibodies from whole blood exploiting the high affinity binding of biotin to avidin (pK 1015 M-1). This study was performed to evaluate the ex vivo biocompatibility of AA minicolumns with human blood. Ten ml AA minicolumns were perfused online ex vivo in the single pass mode with fresh blood from 8 healthy donors at a flow rate of 6.25 ml/min. The anticoagulation consisted of 0.5 IU heparin plus 0.0-2.1 mg citrate per ml of blood. In Part 1 of the study (40 min perfusion, n = 4), the optimal anticoagulation was found to be 0.5 IU heparin plus about 1 mg citrate per ml of blood. In Part 2 of the study, four 80 min test-runs were performed. No signs of hemolysis were found, and the thrombogenicity of the AA gel was negligible. Cell counts and column inlet pressures remained constant; toward the end of the 80 min test-runs, some activation of blood cells (elastase, beta-thromboglobulin), the complement system (C3a, C5a) and the plasmatic coagulation (thrombin-antithrombin complex) was detectable. A moderate initial bradykinin release rapidly subsided to very low levels. In summary, AA minicolumns showed good biocompatibility upon contact with human whole blood and merit further investigation in a closed-loop system for a potential application of direct tumor antibody removal by hemoperfusion.

Adsorption↗
PubMed2000

Effect of low-dose citrate anticoagulation on the clinical safety and efficacy of direct adsorption of lipoproteins (DALI apheresis) in hypercholesterolemic patients: a prospective controlled clinical trial.

Direct adsorption of lipoproteins (DALI) is the first lipid apheresis system compatible with whole blood with the advantage of a very simple procedure. A mixture of heparin plus citrate (ACD-A) is used for the anticoagulation regimen (AR). A clinical, prospective, controlled crossover study was performed to test the safety and efficacy of low-dose citrate (LDC) anticoagulation in DALI. Five chronic DALI patients suffering from coronary heart disease and hypercholesterolemia underwent 3 DALI sessions each using the LDC anticoagulation regimen (60 IU heparin/kg body weight as initial bolus; 1:40 ACD-A: blood as perfusion). This was compared to 3 sessions per patient with the standard AR (bolus of 20 IU heparin/kg, 1:20 ACD-A as perfusion). Patient blood volumes (1.6; average of 7,040 ml) were treated with 750 ml adsorber gel per session at a blood flow rate of 60 ml/min. Mean LDL and Lp(a) reductions exceeded 60% with both AR. No clinical side effects were observed. Both AR controlled the coagulation well as evidenced by a sufficient prolongation of the partial prothrombin time (PTT) and activated clotting time as well as low thrombin-antithrombin (TAT) formation. Biocompatibility parameters exhibited favorable results (low activation of complement and cells, and only slight formation of C3a, C5a, beta-thromboglobulin, elastase, and TNF-alpha). The asymptomatic bradykinin generation was comparable in both study arms. LDC optimized the ionized calcium levels and pH in the efferent blood postadsorber. LDC anticoagulation was safe and effective, and may further improve the tolerance of DALI apheresis in hypercholesterolemic patients.

Adsorption↗
PubMed2000

Immunoadsorption, current status and future developments.

The association of abnormalities in the cellular and humoral immune system with various autoimmune diseases provides the rationale for apheresis technologies. While plasmapheresis or plasma exchange is limited by its non-selective removal of all plasma components, modern apheresis techniques aim to provide more specific elimination according to clinical needs and avoid plasma product replacement. However, the commercialisation has not met the expectations in the early 80's and the number of patients treated by extracorporeal immunoadsorption remains small due to a lack of well-defined controlled trials and limited reimbursement. This review highlights the immunological and technical basis for extracorporeal immunoadsorption, as well as its current status in the treatment of immunologically-mediated diseases.

Animals↗
PubMed2000

Evaluation of microparticle leakage during DALI LDL adsorption in a simulated clinical setting.

The aim of the present study was to investigate microparticle (Mp) leakage during simulated LDL-hemoperfusion using 12 DALI 750 adsorbers and the original DALI hardware under conditions strictly comparable to the clinical situation. Thus, the sessions were divided into 4 sections, i.e. priming and preparation of the adsorber followed by treatment (6-7 L at a flow rate of 60 ml/min) and reinfusion. As Mp counts can be performed only in clear, cell-free media, blood was replaced by normal saline in sections 2-4 of the simulated sessions. Mp counts were analysed for > or = 2, > or = 5, > or = 10 and > or = 25 microm particle sizes in the efferent line post adsorber using a standard light blockage method. As there are no official thresholds for particle release in extracorporeal circuits, the limits for infusion of large fluid volumes of 500, 100 (80), 25 and 5 (3) Mp/ml according to the Europäische Arzneimittelbuch, the British and American Pharmacopoeias were used. Mean particle counts for the sections 3 and 4 in which the patient is connected to the efferent line were 19, 7, 2 and 0 Mp/ml and amounted to < 10% of the above mentioned limits. Modifications of the standard simulation procedure by inserting additional pump stops or using different flow rates during the treatment phase slightly increased Mp leakage, but never exceeded the prescribed limits. In summary, no undue particle release could be detected during simulations of the clinical DALI LDL-adsorption procedure.

Adsorption↗
PubMed2000

Heparin-free DALI LDL-apheresis in hyperlipidemic patients: efficacy, safety and biocompatibility.

BACKGROUND AND AIM OF STUDY: In routine DALI apheresis--the first technique for direct adsorption of lipoproteins from whole blood--heparin plus citrate (ACD-A) is used as anticoagulation regimen. However, recently several publications have warned of heparin-induced thrombocytopenia as a rare but potentially life-threatening complication of heparin administration (HIT type 2). The aim of the present study was therefore to test the efficacy and biocompatibility of DALI using a heparin-free anticoagulation regimen consisting exclusively of citrate. METHODS: Four symptomatic hypercholesterolemic patients on regular DALI apheresis were switched to the heparin-free protocol for two sessions each. Two of the patients were on oral anticoagulation using phenprocoumon. In the weekly sessions, 1.3 patient blood volumes were processed at a blood flow rate of 60 ml/min using ACD-A at a ratio of 1:20 (v/v) during adsorber priming and the session. RESULTS: Clinically, all sessions were essentially uneventful. Uncorrected lipoprotein reductions amounted to 65% for LDL-C, 62% for Lp(a), 53% for VLDL-C, 24% for HDL-C, 17% for triglycerides and 19% for fibrinogen. Cell counts remained virtually constant. No signs of hemolysis or clotting could be detected. Thromboplastin time (Quick) was slightly prolonged and partial thromboplastin time (PTT) moderately elevated in all patients. In contrast, whole blood coagulation time acc. to Lee-White and activated clotting times were increased only in orally anticoagulated patients. Biocompatibility in terms of complement, leukocyte and thrombocyte activation was excellent. Bradykinin activation was moderate peaking at 3038 pg/ml in the efferent line. Systemic thrombin-antithrombin complex (TAT) reflected perfect anticoagulation in orally anticoagulated patients and adequate anticoagulation in the patients without phenprocoumon. CONCLUSION: In this pilot study, heparin-free DALI apheresis was safe and effective and may thus be performed in LDL-apheresis dependent patients who suffer from heparin intolerance.

Adsorption↗
PubMed1999

Therapeutic plasma exchange in patients with chylomicronemia syndrome complicated by acute pancreatitis.

Chylomicronemia syndrome (CMS) is a rare disorder characterized by the presence of chylomicrons in the fasting state causing a milky appearance of plasma, eruptive xanthomas, and hepatosplenomegaly; an acute and potentially life threatening complication is severe acute pancreatitis. The underlying defects are inborn errors of metabolism such as deficiencies of lipoprotein lipase (LPL) or apoprotein C-II (apo C-II) as well as familial hypertriglyceridemia. Moreover, CMS can be precipitated when mild hypertriglyceridemia is exacerbated by additional factors such diabetes mellitus, ethanol abuse, or pregnancy. The purpose of the present study was to retrospectively analyze the results of therapeutic plasma exchange (TPE) in 5 patients transferred to our hospital for severe acute pancreatitis due to chylomicronemia syndrome. In a total of 7 TPE sessions, on average 3,286 +/- 247 ml of plasma (i.e., about 1 patient plasma volume) were treated per session. Triglyceride (TG) levels were decreased from 4,972 +/- 2,469 mg/dl on admission to 1,614 +/- 1,276 mg/dl (-70%) after the TPE sessions, and a further decrease was achieved by conservative treatment. Part of the TG reducing effect of the treatment was probably due to heparin induced lipolysis. Acute pancreatitis was resolved in all cases, and 1 pregnant patient delivered without problems at term. In summary, 1 or 2 TPE sessions sufficed to substantially decrease the bulk of triglycerides in acutely exacerbated chylomicronemia syndrome causing a rapid resolution of acute severe pancreatitis.

Acute Disease↗