Inter-α-inhibitor heavy chain H4 and sepsis-related coagulation disturbances: Another link between innate immunity and coagulation

Background

The protease inhibitor inter-α-inhibitor heavy chain H4 (ITIH4) has been described as an acute-phase reactant and could potentially aid in sepsis monitoring and prognostication.

Objectives

To investigate ITIH4 plasma levels in sepsis patients compared with healthy controls and to examine the association between ITIH4 and acute-phase response markers, blood coagulation, and organ dysfunction in sepsis.

Methods

We performed a post hoc study to a prospective cohort study. Patients with septic shock (n = 39) were enrolled upon intensive care unit admission. ITIH4 was analyzed using an in-house immunoassay. Standard coagulation parameters, thrombin generation, fibrin formation and lysis, C-reactive protein, organ dysfunction markers, Sequential Organ Failure Assessment score, and disseminated intravascular coagulation (DIC) score were registered. ITIH4 levels were also investigated in a murine Escherichia coli sepsis model.

Results

ITIH4 did not display acute-phase behavior as mean ITIH4 levels were not increased in patients with septic shock or in E. coli-infected mice. However, ITIH4 exhibited large interindividual variation in patients with septic shock compared with healthy controls. Low ITIH4 was associated with sepsis-related coagulopathy, including a high DIC score (mean ITIH4: DIC, 203 μg/mL vs non-DIC, 267 μg/mL, P = .01), low antithrombin (r = 0.70, P < .0001) and decreased thrombin generation (mean ITIH4: first peak thrombin tertile, 210 μg/mL vs third peak thrombin tertile, 303 μg/mL, P = .01). ITIH4 showed moderate correlation with arterial blood lactate (ρ = -0.50, P < .001) but only weak correlations with C-reactive protein, alanine transaminase, bilirubin, and Sequential Organ Failure Assessment score (all, ρ < 0.26, P > .05).

Conclusion

ITIH4 is associated with sepsis-related coagulopathy but is not an acute-phase reactant during septic shock.

Lack of P2X7 Receptors Protects against Renal Fibrosis after Pyelonephritis with α-Hemolysin-Producing Escherichia coli

Severe urinary tract infections are commonly caused by sub-strains of Escherichia coli secreting the pore-forming virulence factor α-hemolysin (HlyA). Repeated or severe cases of pyelonephritis can cause renal scarring that subsequently can lead to progressive failure. We have previously demonstrated that HlyA releases cellular ATP directly through its membrane pore and that acute HlyA-induced cell damage is completely prevented by blocking ATP signaling. Local ATP signaling and P2X₇ receptor activation play a key role in the development of tissue fibrosis. This study investigated the effect of P2X₇ receptors on infection-induced renal scarring in a murine model of pyelonephritis. Pyelonephritis was induced by injecting 100 million HlyA-producing, uropathogenic E. coli into the urinary bladder of BALB/cJ mice. A similar degree of pyelonephritis and mortality was confirmed at day 5 after infection in P2X₇^+/+ and P2X₇^-/- mice. Fibrosis was first observed 2 weeks after infection, and the data clearly demonstrated that P2X₇^-/- mice and mice exposed to the P2X₇ antagonist, brillian blue G, show markedly less renal fibrosis 14 days after infection compared with controls (P < 0.001). Immunohistochemistry revealed comparable early neutrophil infiltration in the renal cortex from P2X₇^+/+ and P2X₇^-/- mice. Interestingly, lack of P2X₇ receptors resulted in diminished macrophage infiltration and reduced neutrophil clearance in the cortex of P2X₇^-/- mice. Hence, this study suggests the P2X₇ receptor to be an appealing antifibrotic target after renal infections.

α-Haemolysin production, as a single factor, causes fulminant sepsis in a model of Escherichia coli-induced bacteraemia

α-Haemolysin (HlyA) from uropathogenic Escherichia coli has been demonstrated to be a significant virulence factor for ascending urinary tract infections. Once the E. coli reach the well-vascularised kidneys, there is a high risk of bacteraemia and a subsequent septic host response. Despite this, HlyA has the potential to accelerate the host response both directly and via its ability to facilitate adenosine triphosphate release from cells. It has not been settled whether HlyA aggravates bacteraemia into a septic state. To address this, we used an E. coli strain in a model of acute urosepsis that was either transfected with a plasmid containing the full HlyA operon or one with deletion in the HlyA gene. Here, we show that HlyA accelerates the host response to E. coli in the circulation. Mice exposed to HlyA-producing E. coli showed massively increased proinflammatory cytokines, a substantial fall in circulating thrombocytes, extensive haematuria, and intravascular haemolysis. This was not seen in mice exposed to either E. coli that do not secrete HlyA or vehicle controls. Consistent with the massive host response to the bacteria, the mice exposed to HlyA-producing E. coli died exceedingly early, whereas mice exposed to E. coli without HlyA production and vehicle controls survived the entire observation period. These data allow us to conclude that HlyA is a virulence factor that accelerates a state of bacteraemia into fulminant sepsis in a mouse model.

[Ca2+]i Oscillations and IL-6 Release Induced by α-Hemolysin from Escherichia coli Require P2 Receptor Activation in Renal Epithelia

Urinary tract infections are commonly caused by α-hemolysin (HlyA)-producing Escherichia coli. In erythrocytes, the cytotoxic effect of HlyA is strongly amplified by P2X receptors, which are activated by extracellular ATP released from the cytosol of the erythrocytes. In renal epithelia, HlyA causes reversible [Ca(2+)]i oscillations, which trigger interleukin-6 (IL-6) and IL-8 release. We speculate that this effect is caused by HlyA-induced ATP release from the epithelial cells and successive P2 receptor activation. Here, we demonstrate that HlyA-induced [Ca(2+)]i oscillations in renal epithelia were completely prevented by scavenging extracellular ATP. In accordance, HlyA was unable to inflict any [Ca(2+)]i oscillations in 132-1N1 cells, which lack P2R completely. After transfecting these cells with the hP2Y2 receptor, HlyA readily triggered [Ca(2+)]i oscillations, which were abolished by P2 receptor antagonists. Moreover, HlyA-induced [Ca(2+)]i oscillations were markedly reduced in medullary thick ascending limbs isolated from P2Y2 receptor-deficient mice compared with wild type. Interestingly, the following HlyA-induced IL-6 release was absent in P2Y2 receptor-deficient mice. This suggests that HlyA induces ATP release from renal epithelia, which via P2Y2 receptors is the main mediator of HlyA-induced [Ca(2+)]i oscillations and IL-6 release. This supports the notion that ATP signaling occurs early during bacterial infection and is a key player in the further inflammatory response.

[Femoral pseudoaneurysms in drug addicts]

Four cases of femoral pseudoaneurysms from substance abuse are presented. One patient, a 32 year-old women needed amputation (by disarticulation of the hip) after failed revascularization. Another patient had symptoms of claudication after triple ligation and resection without bypass grafting. The last two had an uneventful recovery: one after saphenous vein bypass, the other after simple resection and repair with a vein patch.

Revascularisation of atherosclerotic mesenteric arteries: experience in 90 consecutive patients

OBJECTIVES

Visceral artery surgery is well known to vascular surgeons, but most have limited personal experience. We report our experience with 90 patients treated for atherosclerotic lesions of the visceral arteries during a 25-year period 1968-1993.

DESIGN

Retrospective study.

SETTING

Department of Vascular Surgery, University Hospital Rigshospitalet, Copenhagen, Denmark.

MATERIALS

54 women and 36 men, aged 56 (median; range: 34-78 years) underwent 109 consecutive mesenteric reconstructions. The indication in 90 primary procedures was acute mesenteric ischaemia of non-embolic origin in 25 patients, chronic ischaemia in 53 and prophylactic reconstruction in connection with aortic surgery in 12 patients. The superior mesenteric artery (SMA) was revascularised in 87 patients and the coeliac axis or common hepatic artery in six. Thus, only three patients had both territories revascularised. Thromboendarterectomy was performed in 15 patients, transposition of the SMA directly into the infrarenal aorta in 30 and bypass in 48 patients.

CHIEF OUTCOME MEASURES

Cumulative symptom-free and survival rates.

MAIN RESULTS

The overall perioperative (30 days) mortality rate was 13%, mainly caused by the high mortality rate of 44% (11 patients) in the acutely operated, as the mortality was 0% in patients operated on electively and only one out of 12 patients (8%) died after a prophylactic operation. Nine of the twelve deaths were due to progressive mesenteric infarction. Cumulated survival rates were 81, 60 and 35% after 5, 10 and 20 years, respectively which indicated a mortality rate three times that of an age- and sex-matched Danish population. During follow-up symptoms recurred in 30 patients, more often following emergency surgery and SMA transposition.

CONCLUSIONS

Mesenteric revascularisation may yield long lasting results. However, surgery for acute ischaemia carries a high mortality rate, emphasising the importance of early surgery.

A phase III trial of zoladex and flutamide versus orchiectomy in the treatment of patients with advanced carcinoma of the prostate

In a multicenter Phase III trial 264 patients with advanced prostatic cancer were randomized to either bilateral orchiectomy or treatment with zoladex supplemented by flutamide. Presently, median follow-up time is 30 months. A small difference in objective response was recorded in favor of the combination therapy, whereas no statistically significant difference was found in subjective response to therapy, time to progression, and overall survival. Adverse effects were more commonly encountered in the pharmacologically treated patients. It is concluded that the combination of zoladex plus flutamide is not clinically superior to orchiectomy in the treatment of patients with advanced carcinoma of the prostate.

Late recurrence of upper urinary tract urothelial tumours

Two case reports of late recurrence of upper urinary tract urothelial tumours 13 years after ipsilateral local resection and 19 years after contralateral nephroureterectomy are used in the discussion on when to perform local resection. In accordance with existing literature we propose local resection in case of low-grade upper urinary tract urothelial tumours.

Functional bladder neck obstruction. Results of endoscopic bladder neck incision in 131 consecutive patients

Endoscopic diathermy incision of the bladder neck was carried out as a routine procedure in 131 consecutive male patients with an established diagnosis of functional bladder neck obstruction. Follow-up after 3 months revealed excellent symptomatic and urodynamic results. Morbidity was low and the post-operative stay in hospital short (median 2 days). Patients must be informed of the risk of retrograde ejaculation associated with the procedure and objective evidence of the diagnosis is essential.

Professional development of nurse practitioners as a function of need motivation, learning style, and locus of control

This study assessed the relationship of loci of control, learning styles, and motivational needs of 53 graduates of the Wichita State University Nurse Clinician Program to amounts and types of professional activities performed in a clinical setting. A self-appraisal was also considered in the analyses. Motivational needs assessed included the needs for achievement, affiliation, and power. Findings revealed that nurse clinicians with moderate need for achievement, high need for affiliation, and moderate need for power performed significantly (p less than .03) more professional activities than nurses with high need for achievement, low need for affiliation, and high need for power. Other findings showed a significant (p less than .04) negative relationship between chance locus of control and self-appraisals. Amounts and types of professional activities performed were not significantly related to loci of control or to learning styles.

A model for the evaluation of allied health education

The variety and complexity of evaluation designs, procedures and philosophies has proved confusing for educators and health practitioners. Many evaluation models do not provide for the scope of information needed by allied health programs and are inflexible in regard to the information needs of individual programs. The model presented here is based on the principles of "Systems Theory," which provides a comprehensive framework for the study of educational programs. Input, process, product and environment components are proposed as a method to study all aspects of program operations. With clearly definable rules for the evaluator and program decision-makers, the faculty can adopt and change the course of the evaluation as they work through the planning, implementation and recycling stages of the model. Use of the model should help programs identify information needs and bring existing evaluation efforts together under a comprehensive umbrella.

Impact of a life planning workshop on perceived locus of control

This study used Rotter's I-E scale to investigate the efficacy of a Life Planning Workshop in facilitating development of an internal locus of control for 5 male and 8 female college students seeking assistance with vocational planning and decision making. Findings showed participants made significantly greater progress ( p < .05) than did a control group of 11 nonparticipants in the development of an internal locus of control.