Post-traumatic Severe Fat Embolism Syndrome with Uncommon CT Findings

Although the diagnosis of fat embolism syndrome is usually based on clinical findings, we describe ill-defined centrilobular and subpleural nodules in addition to ground-glass opacities and consolidation on a computed tomography scan of the chest in a trauma patient with fat embolism syndrome. The nodules presumably represent alveolar oedema, microhaemorrhage and an inflammatory response secondary to ischaemia and cytotoxic emboli in fat embolism syndrome. The literature of computed tomography findings in patients with fat embolism syndrome is reviewed and summarized.

Effect of isotonic versus hypotonic maintenance fluid therapy on urine output, fluid balance, and electrolyte homeostasis: a crossover study in fasting adult volunteers

Background. Daily and globally, millions of adult hospitalized patients are exposed to maintenance i.v. fluid solutions supported by limited scientific evidence. In particular, it remains unclear whether fluid tonicity contributes to the recently established detrimental effects of fluid, sodium, and chloride overload.

Methods. This crossover study consisted of two 48 h study periods, during which 12 fasting healthy adults were treated with a frequently prescribed solution (NaCl 0.9% in glucose 5% supplemented by 40 mmol litre⁻¹ of potassium chloride) and a premixed hypotonic fluid (NaCl 0.32% in glucose 5% containing 26 mmol litre⁻¹ of potassium) at a daily rate of 25 ml kg⁻¹ of body weight. The primary end point was cumulative urine volume; fluid balance was thus calculated. We also explored the physiological mechanisms behind our findings and assessed electrolyte concentrations.

Results. After 48 h, 595 ml (95% CI: 454–735) less urine was voided with isotonic fluids than hypotonic fluids (P<0.001), or 803 ml (95% CI: 692–915) after excluding an outlier with ‘exaggerated natriuresis of hypertension’. The isotonic treatment was characterized by a significant decrease in aldosterone (P<0.001). Sodium concentrations were higher in the isotonic arm (P<0.001), but all measurements remained within the normal range. Potassium concentrations did not differ between the two solutions (P=0.45). Chloride concentrations were higher with the isotonic treatment (P<0.001), even causing hyperchloraemia.

Conclusions. Even at maintenance rate, isotonic solutions caused lower urine output, characterized by decreased aldosterone concentrations indicating (unintentional) volume expansion, than hypotonic solutions and were associated with hyperchloraemia. Despite their lower sodium and potassium content, hypotonic fluids were not associated with hyponatraemia or hypokalaemia.

Clinical trial registration. ClinicalTrials.gov (NCT02822898) and EudraCT (2016-001846-24).

The effects of antibiotic cycling and mixing on antibiotic resistance in intensive care units: a cluster-randomised crossover trial

BACKGROUND

Whether antibiotic rotation strategies reduce prevalence of antibiotic-resistant, Gram-negative bacteria in intensive care units (ICUs) has not been accurately established. We aimed to assess whether cycling of antibiotics compared with a mixing strategy (changing antibiotic to an alternative class for each consecutive patient) would reduce the prevalence of antibiotic-resistant, Gram-negative bacteria in European intensive care units (ICUs).

METHODS

In a cluster-randomised crossover study, we randomly assigned ICUs to use one of three antibiotic groups (third-generation or fourth-generation cephalosporins, piperacillin-tazobactam, and carbapenems) as preferred empirical treatment during 6-week periods (cycling) or to change preference after every consecutively treated patient (mixing). Computer-based randomisation of intervention and rotated antibiotic sequence was done centrally. Cycling or mixing was applied for 9 months; then, following a washout period, the alternative strategy was implemented. We defined antibiotic-resistant, Gram-negative bacteria as Enterobacteriaceae with extended-spectrum β-lactamase production or piperacillin-tazobactam resistance, and Acinetobacter spp and Pseudomonas aeruginosa with piperacillin-tazobactam or carbapenem resistance. Data were collected for all admissions during the study. The primary endpoint was average, unit-wide, monthly point prevalence of antibiotic-resistant, Gram-negative bacteria in respiratory and perineal swabs with adjustment for potential confounders. This trial is registered with ClinicalTrials.gov, number NCT01293071.

FINDINGS

Eight ICUs (from Belgium, France, Germany, Portugal, and Slovenia) were randomly assigned and patients enrolled from June 27, 2011, to Feb 16, 2014. 4069 patients were admitted during the cycling periods in total and 4707 were admitted during the mixing periods. Of these, 745 patients during cycling and 853 patients during mixing were present during the monthly point-prevalence surveys, and were included in the main analysis. Mean prevalence of the composite primary endpoint was 23% (168/745) during cycling and 22% (184/853) during mixing (p=0·64), yielding an adjusted incidence rate ratio during mixing of 1·039 (95% CI 0·837-1·291; p=0·73). There was no difference in all-cause in-ICU mortality between intervention periods.

INTERPRETATION

Antibiotic cycling does not reduce the prevalence of carriage of antibiotic-resistant, Gram-negative bacteria in patients admitted to the ICU.

FUNDING

European Union Seventh Framework Programme.

Pivotal Role for the Visceral Fat Compartment in the Release of Persistent Organic Pollutants During Weight Loss

CONTEXT

Polychlorinated biphenyls (PCBs), are implicated as potential endocrine disruptors and obesogens. These lipophilic substances are preferentially stored in the fat compartment and released into the circulation during weight loss.

OBJECTIVE

The aim of this study was to examine the contribution of abdominal adiposity, and visceral adiposity in particular, to the increase of serum PCB levels during weight loss.

MATERIALS AND METHODS

Fourty-five obese women were prospectively recruited. Twenty individuals received dietary counseling and 25 underwent bariatric surgery. Anthropometric data were collected and intra-abdominal adiposity was assessed by measurement computed tomography scanning of the abdominal fat compartment, delineating the visceral and subcutaneous compartment. Serum levels of 27 PCBs were determined and the sum of all PCBs (ΣPCBs) calculated. Follow-up measurements of anthropometric data, computed tomography scanning, and PCB levels were performed after 6 months in all patients.

RESULTS

In patients who lost weight, serum ΣPCB levels displayed an increase after 6 months of approximately 50%. Both correlation and regression analysis, focusing on the relative contribution of the visceral vs the subcutaneous fat compartment, suggested that the increase in ΣPCB serum levels after 6 months of weight loss was more pronounced in patients losing relatively more visceral adipose tissue. This trend could be established in the diet-treated, but not the surgery-treated subgroup.

CONCLUSION

Our study suggests that the contribution of PCBs released from the visceral fat compartment might be more pronounced compared with the subcutaneous fat compartment during weight loss. These findings are present in the entire study group whereas subanalysis of the diet vs surgery groups suggested the same effect in the diet group but failed to reach statistical significance in the surgery group. This suggests a possible weight-loss method-specific effect.

Possible pathogenic mechanism of propofol infusion syndrome involves coenzyme q

BACKGROUND

Propofol is a short-acting intravenous anesthetic agent. In rare conditions, a life-threatening complication known as propofol infusion syndrome can occur. The pathophysiologic mechanism is still unknown. Some studies suggested that propofol acts as uncoupling agent, others suggested that it inhibits complex I or complex IV, or causes increased oxidation of cytochrome c and cytochrome aa3, or inhibits mitochondrial fatty acid metabolism. Although the exact site of interaction is not known, most hypotheses point to the direction of the mitochondria.

METHODS

Eight rats were ventilated and sedated with propofol up to 20 h. Sequential biopsy specimens were taken from liver and skeletal muscle and used for determination of respiratory chain activities and propofol concentration. Activities were also measured in skeletal muscle from a patient who died of propofol infusion syndrome.

RESULTS

In rats, authors detected a decrease in complex II+III activity starting at low tissue concentration of propofol (20 to 25 µM), further declining at higher concentrations. Before starting anesthesia, the complex II+III/citrate synthase activity ratio in liver was 0.46 (0.25) and in skeletal muscle 0.23 (0.05) (mean [SD]). After 20 h of anesthesia, the ratios declined to 0.17 (0.03) and 0.12 (0.02), respectively. When measured individually, the activities of complexes II and III remained normal. Skeletal muscle from one patient taken in the acute phase of propofol infusion syndrome also shows a selective decrease in complex II+III activity (z-score: -2.96).

CONCLUSION

Propofol impedes the electron flow through the respiratory chain and coenzyme Q is the main site of interaction with propofol.

Mechanical and electrical equipment interference provokes a misleading Neurally Adjusted Ventilatory Assist (NAVA) EAdi signal

BACKGROUND

Neurally Adjusted Ventilatory Assist (NAVA) offers synchronized proportional pressure in accordance with the electrical activity of the diaphragm (EAdi). NAVA relies on the EAdi to trigger the respiratory cycle and then adjusts the ventilatory assist to the neural drive. The technique necessitates a catheter with bipolar microelectrodes positioned near the crural diaphragm where this signal can be captured. Capturing a reliable EAdi signal is a condition sine qua non for using NAVA as a mode of ventilation. The displayed signal represents the sum of the electrical activity of the muscle action potential of the diaphragm and is expressed in microvolts.

METHODS

A technical note illustrated by a case series in the intensive care unit (ICU) of a tertiary referral hospital with experience using NAVA.

RESULTS

Here, we report on three separate cases in which the use of an intra-aortic balloon catheter, a pacemaker and a heating device all resulted in a distortion of the EAdi signal, despite good positioning of the catheter. In a fourth case, we observed internal interference from leaking cardiac electrical activity due to the malpositioning of the EAdi catheter in a patient with atrial fibrillation.

CONCLUSION

We illustrate that the detection and therefore interpretation of the EAdi signal during NAVA can be influenced by mechanical and electrical interference by other equipment used in the ICU or from endogenous leaking cardiac activity.

Severe influenza A(H1N1)2009 infection: a single centre experience and review of the literature

The first influenza pandemic of the 21st century started in April 2009 with an outbreak of swine origin influenza A(H1NI)2009 in Mexico and the United States. While generally a mild disease affecting mostly school-aged children and young adults, most attention went to severe cases of pneumonia in young previously healthy individuals or individuals belonging to a risk group. In this article we review the literature on the presentation and management of severe cases of influenza A(H1N1)2009 in the intensive care unit (ICU), and describe our own experience in a tertiary referral centre with ECMO facilities. Pregnant women and (bone marrow) transplant patients are two known risk groups for severe influenza described more thoroughly in this paper.These severely ill patients are characterized by respiratory failure, resulting often in the need of mechanical ventilation. As Oseltamivir resistance remains low up till now, early antiviral therapy with Oseltamivir is warranted in these cases. Despite pharmacological and ventilator management, refractory hypoxaemia is described frequently in these patients, with need for rescue therapies like nitric oxide inhalation, high frequency ventilation, and extracorporeal membrane oxygenation. The value of the use of corticosteroids is under discussion. Despite advances in management strategies, mortality and morbidity in these severe cases remains high. In the first influenza season after the pandemic, winter 2010/2011, influenza A(H1N1)2009 is the major influenza A strain in Europe, resulting in reports with increased mortality and morbidity compared to pre-pandemic seasonal influenza. "Continuing vigilance for severe influenza in patients not belonging to the classical influenza risk group might still be warranted for the upcoming influenza season".

Neuromonitoring in traumatic brain injury

Current approaches to monitoring in severe traumatic brain injury (TBI) include a wide array of modalities, providing insight into pressure parameters, oxygenation, perfusion, electrophysiology and metabolism of the brain. The intent of "multimodality monitoring" is to obtain a better understanding of what is going on within the brain of an individual patient in order to target treatment more appropriately. In this review we highlight the current status of neuromonitoring for TBI with a specific focus on how advanced analysis and integration of these parameters may be used to implement more personalized treatment approaches. In particular, combining information from different parameters and performing dynamic testing offers the potential to better understand the pathophysiological mechanisms active in the brain of a particular patient. Rather than persisting in a standardized "one size fits all" approach to therapy or continuing down the separate tracts of goal directed therapy, we suggest to think more in terms of "individualized therapeutic strategies" more focused on the specific requirements of each patient. Given the considerable data overload in multimodality monitoring and the complexity in interpretation of signals from multiple sources, specific attention needs to be directed to data processing and user-friendly displays. Intense collaboration and interaction between clinicians, basic researchers, IT-experts, nurses and industry will be required to further advance the fields towards more personalized approaches.

Impact of a standardized nurse observation protocol including MEWS after Intensive Care Unit discharge

BACKGROUND

Analysis of in-hospital mortality after serious adverse events (SAE's) in our hospital showed the need for more frequent observation in medical and surgical wards. We hypothesized that the incidence of SAE's could be decreased by introducing a standard nurse observation protocol.

AIM

To investigate the effect of a standard nurse observation protocol implementing the Modified Early Warning Score (MEWS) and a color graphic observation chart.

METHODS

Pre- and post-intervention study by analysis of patients records for a 5-day period after Intensive Care Unit (ICU) discharge to 14 medical and surgical wards before (n=530) and after (n=509) the intervention.

RESULTS

For the total study population the mean Patient Observation Frequency Per Nursing Shift (POFPNS) during the 5-day period after ICU discharge increased from .9993 (95% C.I. .9637-1.0350) in the pre-intervention period to 1.0732 (95% C.I. 1.0362-1.1101) (p=.005) in the post-intervention period. There was an increased risk of a SAE in patients with MEWS 4 or higher in the present nursing shift (HR 8.25; 95% C.I. 2.88-23.62) and the previous nursing shift (HR 12.83;95% C.I. 4.45-36.99). There was an absolute risk reduction for SAE's within 120h after ICU discharge of 2.2% (95% C.I. -0.4-4.67%) from 5.7% to 3.5%.

CONCLUSION

The intervention had a positive impact on the observation frequency. MEWS had a predictive value for SAE's in patients after ICU discharge. The drop in SAE's was substantial but did not reach statistical significance.

Excessive eosinophilia as paraneoplastic syndrome in a patient with non-small-cell lung carcinoma: a case report and review of the literature

Hypereosinophilia is a phenomenon which is associated with a broad variety of allergic, infectious, paraneoplastic and systemic diseases. Depending on the aetiology, these disorders differ in severity from self-limiting to life-threatening. Although it is well known that hypereosinophilia can occur in association with a solid tumour, exact numbers of incidence are lacking. We describe a patient with respiratory insufficiency and an elevated level of eosinophils in the peripheral blood. A diagnostic work-up revealed the presence of a disseminated non-small-cell carcinoma of the lung; an association not frequently described.

Environmental pollutants and type 2 diabetes: a review of mechanisms that can disrupt beta cell function

The prevalence of diabetes mellitus is currently at epidemic proportions and it is estimated that it will increase even further over the next decades. Although genetic predisposition and lifestyle choices are commonly accepted reasons for the occurrence of type 2 diabetes, it has recently been suggested that environmental pollutants are additional risk factors for diabetes development and this review aims to give an overview of the current evidence for this. More specifically, because of the crucial role of pancreatic beta cells in the development and progression of type 2 diabetes, the present work summarises the known effects of several compounds on beta cell function with reference to mechanistic studies that have elucidated how these compounds interfere with the insulin secreting capacity of beta cells. Oestrogenic compounds, organophosphorus compounds, persistent organic pollutants and heavy metals are discussed, and a critical reflection on the relevance of the concentrations used in mechanistic studies relative to the levels found in the human population is given. It is clear that some environmental pollutants affect pancreatic beta cell function, as both epidemiological and experimental research is accumulating. This supports the need to develop a solid and structured platform to fully explore the diabetes-inducing potential of pollutants.

Methadone-induced toxic leukoencephalopathy: MR imaging and MR proton spectroscopy findings

We report the clinical, MR imaging, and proton MR spectroscopy findings in a middle-aged woman with proved methadone-induced toxic leukoencephalopathy. The imaging characteristics of this unusual condition have been reported only rarely in the medical literature. We show that the imaging findings in methadone-induced toxic leukoencephalopathy are similar, though not identical, to previously reported cases of neurologic deterioration due to heroin inhalation.

Acute hemiplegia caused by a retrograde cerebral venous air embolism after central venous catheter removal: an illustrative case

Central venous catheters are widely used in clinical practice. Air embolism is a rare, but potentially life threatening complication of central venous catheterisation. We describe a case of collapse and transient hemiplegia after removal of central venous catheter. This was accidentally performed with the patient in upright position. A CT scan of the brain demonstrated air in the sinus cavernosus bilaterally and at the posterior wall of the foramen magnum.

A series of five adult cases of respiratory syncytial virus-related acute respiratory distress syndrome

Respiratory syncytial virus is a common cause of respiratory tract disease in children, predominantly presenting with mild symptoms. We present five cases of respiratory syncytial virus infection of the lower respiratory tract in immunocompromised adults suffering from severe respiratory insufficiency leading to bilateral pneumonia and fulfilling the criteria for acute respiratory distress syndrome. Respiratory syncytial virus was cultured as the only pathogen in the bronchoalveolar lavage fluid in four of these patients. Despite various therapeutic interventions, only one patient survived. Respiratory syncytial virus was implicated as a direct cause of respiratory failure. Respiratory syncytial virus may be an underestimated cause of severe respiratory failure and acute respiratory distress syndrome in the immunocompromised adult admitted to the intensive care unit.

Campylobacter jejuni-induced acute transverse myelitis

STUDY DESIGN

Case report.

SETTING

University Hospital of Antwerp, tertiary referral hospital of the University of Antwerp, Edegem, Belgium.

CASE REPORT

Campylobacter jejuni infection is related to various syndromes in which the peripheral nervous system is involved. An immune response is triggered through molecular mimicry between gangliosides of the peripheral nervous system and lipo-oligosaccharides of C. jejuni. We report a case of a previously healthy 17-year-old girl, who developed clinical manifestations of acute transverse myelitis (ATM) 7 days after a culture-proven C. jejuni enteritis. High titres of serum IgG antibodies to the ganglioside GM1 were found in the acute phase of disease, which decreased with clinical recovery. These antibodies cross-reacted with C. jejuni lipo-oligosaccharides, indicating that C. jejuni infections may induce ATM.

CONCLUSIONS

Only a few cases of C. jejuni infection associated with demyelination of the central nervous system or spinal cord have been described. Physicians should be aware that C. jejuni might be another cause of transverse myelitis.

High-dose cefepime as an alternative treatment for infections caused by TEM-24 ESBL-producing Enterobacter aerogenes in severely-ill patients

This study evaluated retrospectively the efficacy of treatment with cefepime vs. a carbapenem, in combination with amikacin or ciprofloxacin, for seriously-ill patients infected with ESBL-producing Enterobacter aerogenes who were admitted to an intensive care unit. Forty-four episodes of infection were investigated in 43 patients: 21 treated with cefepime; 23 with a carbapenem. The two treatment groups did not differ statistically in terms of age, APACHE II scores, and infection sites, but the average duration of antibiotic exposure was significantly shorter in the cefepime group (8.5 days vs. 11.4 days; p 0.04). Clinical improvement was seen in 62% of patients receiving cefepime vs. 70% of patients receiving a carbapenem (p 0.59). Bacteriological eradication was achieved in 14% of patients receiving cefepime vs. 22% of patients receiving a carbapenem (p 0.76). The 30-day mortality rates related to infection were 33% in the cefepime group and 26% in the carbapenem group (p 0.44). Thus, outcome parameters did not differ significantly between the two groups. Nevertheless, a statistically significant increase in failure to eradicate ESBL-producing E. aerogenes was observed as the MICs of cefepime rose (p 0.017). Pulsed-field gel electrophoresis revealed three distinct clones, but one predominant clone harbouring the bla(TEM-24) gene was associated with most (42/44) of the episodes of infection. It was concluded that cefepime may be an alternative agent for therapy of severe infections caused by TEM-24 ESBL-producing E. aerogenes, although further studies are required to confirm these observations.

Messenger RNA electroporation is highly efficient in mouse embryonic stem cells: successful FLPe- and Cre-mediated recombination

Development of efficient short-term gene transfer technologies for embryonic stem (ES) cells is urgently needed for various existing and new ES cell-based research strategies. In this study, we present a highly efficient, nonviral non-DNA technology for genetic loading of mouse ES cells based on electroporation of defined mRNA. Here, we show that mouse ES cells can be efficiently loaded with mRNA encoding a green fluorescent reporter protein, resulting in a level of at least 90% of transgene expression without loss of cell viability and phenotype. To show that transgenes, introduced by mRNA electroporation, exert a specific cellular function in transfected cells, we electroporated stably transfected ES cell lines with mRNA encoding FLPe or Cre recombinase proteins in order to excise an FRT- or LoxP-flanked reporter gene. The results, as determined by the disappearance and/or appearance of a fluorescent reporter gene expression, show that FLPe and Cre recombinase proteins, introduced by mRNA electroporation, efficiently exert their function without influence on further culture of undifferentiated ES cell populations and their ability to differentiate towards a specific lineage.

Current challenges in human embryonic stem cell research: directed differentiation and transplantation tolerance

Research towards potential curative transplantation of human embryonic stem (hES) cell-derived grafts in a variety of diseases has become an important topic since the successful derivation and propagation of hES cells from the inner cell mass of a blastocyst. However, clinical applicability can only be established after intensive laboratory studies that should elaborate on two major topics: A) the development of efficient, controlled and stable hES cell differentiation protocols for any specific cell type, and B) the induction of immunological tolerance against transplanted allogeneic hES cell-derived cell types. This review will briefly discuss: A) current possibilities in hES cell differentiation, followed by the development of viral, DNA and mRNA-based gene transfer strategies for hES cells, and B) possible immune modulation strategies for inducing immune tolerance against allogeneic hES cell transplants.

Inadvertent intrathecal use of ionic contrast agent

Intrathecal administration of ionic contrast media may cause severe and fatal neurotoxic reactions due to their hyperosmolarity and ionic nature. They are therefore strictly contraindicated for all radiologic applications involving the central nervous system (e.g., myelography). We present a case in which ioxitalamate was accidentally injected intrathecally. The patient recovered completely due to a combination of the different therapeutic options reported in the literature, including early mechanical ventilation and neuromuscular paralysis, aggressive control of seizures, elevation of head and trunk to prevent cephalad migration of contrast, steroids, cerebrospinal fluid drainage and lavage and prophylactic antibiotics.

Early diagnosis of cerebral fat embolism syndrome by diffusion-weighted MRI (starfield pattern)

BACKGROUND

Cerebral fat embolism syndrome is a rare, but potentially lethal, complication of long bone fractures. Neurological symptoms are variable, and the clinical diagnosis is difficult. The purpose of this case study is to demonstrate the value of diffusion-weighted MRI of the brain for early diagnosis of fat embolism syndrome. Case Description- A non-head-injured 18-year-old woman suffered acute mental status changes 21 hours after an uncomplicated fracture of the left tibia. MRI of the brain was performed 48 hours after injury. T2-weighted images showed multiple nonconfluent areas of high signal intensity, which, on the diffusion-weighted scans, were revealed as bright spots on a dark background ("starfield" pattern). We suggest that this indicates areas of restricted diffusion that are due to cytotoxic edema, resulting from multiple microemboli.

CONCLUSIONS

High-intensity lesions in the brain on diffusion-weighted images may serve as an early-appearing and more sensitive indicator of the diagnosis of fat embolism in the clinical context of long bone injury without head trauma.

Natural inhibitors of neutrophil function in acute respiratory distress syndrome

OBJECTIVE

Neutrophils play a key role in the physiopathogenesis of acute lung injury in general and acute respiratory distress syndrome (ARDS) in particular. To identify the anti-inflammatory mediators with a protective effect on lung tissue damage in ARDS, we correlated the concentration of the Clara cell 16-kD protein (CC16; an inhibitor of neutrophil chemotaxis), angiogenin (an inhibitor of degranulation), and the total radical oxygen neutralizing activity with the amount of elastase (a marker of neutrophil activation) and with the Pao2/Fio2 ratio, which is inversely related to lung injury.

SETTING

University hospital.

PATIENTS

Patients with ARDS (n = 12) and patients at risk for developing ARDS (n = 14).

INTERVENTIONS

Patients underwent bronchoalveolar lavage 12 hrs after diagnosis of ARDS or at-risk status.

MEASUREMENTS AND MAIN RESULTS

The amount of CC16 and radical oxygen neutralizing activity was not significantly different in patients with or at risk for ARDS. In contrast, the amount (mean +/- sem) of angiogenin in the bronchoalveolar lavage of ARDS patients (45 +/- 14 ng/mL, n = 12) was increased 11-fold (p <.05) compared with patients at risk for ARDS (4 +/- 1 ng/mL, n = 14). In patients with ARDS, the amount of protein and angiogenin in bronchoalveolar lavage increased with decreasing concentration of CC16 (p <.05). In addition, CC16 correlated with the Pao2/Fio2 ratio (p <.05) and inversely with the amount of elastase (p <.05) and thus may be regarded as a reliable protective agent for lung injury.

CONCLUSION

A high concentration of CC16, a natural inhibitor of neutrophil function, decreases neutrophil-mediated lung damage of patients with ARDS. Strategies to increase natural anti-inflammatory agents, and thus influence the disruption of the balance between natural inflammatory and anti-inflammatory or protective factors, could be useful to modulate the tissue destruction and the course of ARDS.

Perforating oesophageal carcinoma presenting as necrotizing fasciitis of the neck

A patient with a history of schizophrenia was admitted to our hospital in an already severe stage of necrotizing fasciitis of the neck, complicated with mediastinitis and gangrene. Later on, he also developed a vena cava superior syndrome and sepsis. In the few cases and small series described in the literature, necrotizing fasciitis of the neck is usually associated with surgery or trauma. Less frequently, an orodental or pharyngeal infection, often innocuous, is the underlying cause. None of these causes could be identified in our patient. Initially, on computer-assisted tomography (CT) scan, a tracheal rupture was suspected, but this diagnosis could not be confirmed on bronchoscopic examination. On gastroscopy, a stenotic oesophageal segment was discovered. Biopsy of this segment showed a poorly differentiated squamous cell carcinoma. The patient died in sepsis. Autopsy confirmed the presence of a large proximal oesophageal tumour with perforation. As far as we know, no case of a necrotizing fasciitis of the neck caused by perforation of a formerly unknown oesophageal carcinoma has been reported. Even mediastinitis, with or without gangrene, is rarely associated with oesophageal cancer, and in the few cases reported it is always due to fistulization after surgery.

Surprising findings following a Belgian food contamination with polychlorobiphenyls and dioxins

We found that 12.1% of Belgian export meat samples from chicken or pork, unrelated to the PCB/dioxin crisis from 1999, contained more than 50 ng polychlorinated biphenyls (PCBs)/g fat and that 6.5% of samples contain more than 20 ng/g fat for the sum of 1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane (DDT) and its metabolites. Part of this background contamination stems from imported animal feed ingredients (fish flour and grains), sometimes contaminated by recent use of DDT, as can be deduced from the ratio between DDT and its main metabolite, 1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene (DDE). However, after comparing PCB concentrations in fish flour and grains with those found in meat, we suggest that the high concentrations stem from recycled fat. This is the first paper describing background concentrations of PCBs in animal meat from Belgium.

Reperfusion injury after focal myocardial ischaemia: polymorphonuclear leukocyte activation and its clinical implications

The only way to rescue ischaemic tissue is to re-instate the oxygen supply to the tissue. However reperfusion of the ischaemic area not only oxygenates the tissue but also initiates a cascade of processes, which may in some cases result in temporary dysfunction of the myocardium. In order to devise protective measures, it is essential to understand the mechanisms and the triggers of this reperfusion phenomenon. In this review we will mainly focus on the inflammatory response caused by reperfusion. We will cover the different steps of polymorphonuclear leukocyte activation and will briefly discuss the molecular biology of the receptors involved. The currently used pharmacological medications in acute cardiology will be reviewed and in particular their actions on polymorphonuclear leukocyte activation, adhesion and degranulation. This review is a compilation of the current knowledge in the field and the therapeutic progress in the prevention of reperfusion injury made today.

Successful recovery after ventricular fibrillation in a patient with Kawasaki disease

Kawasaki disease (KD) is an uncommon cause of sudden death in young adults in Europe. Angiographically, the disease is characterized by coronary artery aneurysms which can be fully obstructed by acute thrombosis or by progression of the disease. If diagnosis of KD is made, immediate investigation should be made to determine whether ischemia is occurring and if so, to establish optimal time for revascularisation or cardiac transplantation. We describe an 18-year-old Caucasian male who was not previously known to have KD and who suffered from an acute myocardial infarction complicated by ventricular fibrillation, caused by acute thrombosis of a coronary artery aneurysm.

Encephalomyelitis-associated antimyelin autoreactivity induced by streptococcal exotoxins

OBJECTIVE

After implicating Streptococcus pyogenes as causing acute disseminated encephalomyelitis (ADEM) in a child, we wanted to prove that in vivo activation of autoreactive T lymphocytes by superantigens of this Streptococcus contributed to the dramatic demyelination.

BACKGROUND

ADEM is a demyelinating disorder of the CNS sharing many similarities with MS. Demyelination in MS is considered to be the result of an autoimmune process mediated by autoreactive T lymphocytes with specificity for myelin antigens.

METHODS

Phenotypic analysis and proliferation assays on blood monocytes, as well as isolation of myelin basic protein (MBP)-reactive T-cell lines/clones; and TCR repertorium analysis by PCR-ELISA and cytokine production.

RESULTS

1) The blood T-cell receptor (TCR) repertoire was compatible with in vivo expansion induced by S. pyogenes exotoxins. 2) TCR expression analysis indicated clonal expansion of CD8+ MBP-reactive T cells, suggesting in vivo activation. MBP-reactive T cells showed crossreactivity to S. pyogenes supernatant and exotoxins. 3) Cytokine mRNA quantification of the mononuclear cells revealed a Th2-biased profile.

CONCLUSION

In vivo exposure to S. pyogenes may have induced activation of pathogenic myelin reactive T cells, contributing to the dramatic inflammatory demyelination.

Traumatic basilar artery dissection in a child: need for anticoagulation?

Dissection of a cerebral blood vessel is a rare complication of acute neurotrauma with a high incidence of morbidity and mortality. We report on a case of a pediatric patient with severe neurological symptoms in whom angiography showed evidence of a basilar artery dissection. The patient was heparinized and recovered uneventfully.

A case of aldicarb poisoning: a possible murder attempt

A couple showing signs of cholinergic crisis was admitted to the hospital. Analyses with high-performance liquid chromatography and gas chromatography-mass spectrometry conducted on serum, urine, and stomach contents that were collected few hours after first symptoms showed the presence of aldicarb, which is the most potent carbamate insecticide on the market. A murder attempt was suspected because the patients showed the first signs some minutes after drinking coffee upon returning home and no commercial products containing aldicarb were found in the house. Because of the reversibility of inhibition of acetylcholinesterase, the patients recovered after treatment with atropine and toxogonin. They left the hospital after 12 days. To our knowledge, the serum concentrations of aldicarb reported in this paper are the highest reported for a nonfatal case.

Oxidatively modified proteins in bronchoalveolar lavage fluid of patients with ARDS and patients at-risk for ARDS

Oxidative stress in acute respiratory distress syndrome (ARDS) is considered as an important pathophysiological mechanism in acute impairment of lung function. The present study investigated whether a pulmonary oxidant-antioxidant imbalance is indicated by substantial oxidative modification of proteins in bronchoalveolar lavage (BAL) fluid. Oxidatively modified proteins in BAL fluid, as measured by the reduction of protein carbonyl groups with tritiated borohydride, were studied in control subjects, patients with clinically established ARDS, and patients considered at-risk for ARDS because they had had coronary bypass surgery. Subsets of these at-risk patients were pretreated either with methylprednisolone or N-acetylcysteine. The carbonyl content of BAL fluid proteins was greatly increased in ARDS patients (5.0+/-13 nmol carbonyl x mL(-1) BAL fluid; mean+/-SEM; p=0.0004; n=10) and moderately increased in the untreated patients at-risk for ARDS (1.3+/-0.2 nmol x mL(-1); p=0.027; n=19) compared with controls (0.8+/-0.2 nmol x mL(-1); n=12). The two other at-risk groups pretreated either with methylprednisolone or N-acetylcysteine showed carbonyl values that were statistically not different from the controls (1.2+/-0.2 nmol x mL(-1); p=0.13; n=13, and 1.1+/-0.3 nmol x mL(-1); p=0.40; n=8, respectively). These results show that oxidatively modified proteins clearly accumulated in bronchoalveolar lavage fluid of acute respiratory distress syndrome patients, and to a minor extent in untreated at-risk patients. These data suggest a severe oxidant-antioxidant imbalance in acute respiratory distress syndrome.

Diagnosis and nonsurgical management of bile leak complicated by biloma after blunt liver injury: report of two cases

We report on two patients with biliary tract injury and associated biloma following blunt abdominal trauma. Both patients underwent emergency surgery because of hemodynamic instability and bloody peritoneal aspiration. Computed tomography in the postoperative days showed severe hepatic parenchymal injury and the presence of hypodense collections with intraparenchymal and subcapsular extension, suggestive for biloma, but otherwise failed to demonstrate the exact location of the bile duct injury. One of them underwent temporary percutaneous drainage. Bile duct injury was well demonstrated on endoscopic retrograde cholangiography (ERCP) and treated by endobiliary stent placement. This report advocates the use of ERCP and endobiliary stenting in the management of biliary injury resulting from liver trauma.

Coronary artery spasm complicating anaphylaxis secondary to skin disinfectant

We report a patient in whom presumed vasospasm of an angiographically normal coronary artery led to severe transmural myocardial ischemia. To our knowledge, this is the first case in which an allergic reaction to locally applied chlorhexidine caused such a severe reaction.

Localization of extracellular superoxide dismutase in rat lung: neutrophils and macrophages as carriers of the enzyme

Immunohistochemistry (IHC) and in situ hybridization (ISH) was used to localize extracellular superoxide dismutase (EC-SOD) and its mRNA in rat lung before and after a lipopolysaccharide (LPS)- and hyperoxia-induced inflammation. In control rats, EC-SOD mRNA was synthesized in macrophages and in cells of the arterial vessel walls and the alveolar septa. The EC-SOD protein was mainly localized in plasma and on the apical side of the epithelial cells located near bronchus-associated lymphoid tissue (BALT). ISH did not reveal major changes in the distribution of EC-SOD mRNA upon induction of inflammation. In contrast, IHC demonstrated a progressive staining of the epithelium of the larger bronchi for the protein. Neutrophils and macrophages invading the lung showed an intensive staining for the EC-SOD protein concomitantly with a decrease of the enzyme in the plasma. Twenty-four hours after LPS stimulation only a spotty positivity remained on neutrophils in and between the alveolar spaces. In the bronchoalveolar lavage fluid (BALF), only macrophages showed a strong positivity for EC-SOD mRNA while the protein was detected in macrophages and neutrophils. Exposure to hyperoxia did not affect the distribution of EC-SOD mRNA and protein. The presented data demonstrated that in lung tissue the EC-SOD enzyme may have a protective function for activated macrophages, neutrophils, and lympoid tissue-associated epithelial cells.

Decreased release of nitric oxide (NO) by alveolar macrophages after in vivo loading of rats with either iron or ethanol

Alveolar macrophages were isolated by pulmonary lavage from rats which had been either chronically overloaded with iron by intraperitoneal injections of iron dextran for four weeks, or rendered alcoholic by administration of increasing concentrations of alcohol vapour, also for four weeks. Although the hepatic iron content increased in both groups of animals, only the macrophages isolated from the iron-loaded animals showed a significant increase in iron content (P = < 0.05). Furthermore, in these macrophages there was a significant increase in oxidative tone as demonstrated by a six fold increase in superoxide dismutase activity. In both the iron-loaded and chronically alcoholised macrophages, there was a significant diminution in nitric oxide release after stimulation with lipopolysaccharide and/or interferon-gamma, which impaired the ability of both of these groups of macrophages to inhibit the germination of spores from the fungus Rhizopus, a nitric oxide-dependent process. Such an alteration in nitric oxide release reduces the macrophage's microbicidal activity.

Lung volume reduction surgery as an emergency and life-saving procedure

Lung volume reduction surgery (LVRS) is emerging as a promising and unique therapeutic option for rigorously selected patients with severe debilitating emphysema. A 51 yr old man with generalized emphysema developed bilateral pneumothoraces during his first holiday abroad. Due to respiratory insufficiency, intubation and mechanical ventilation were necessary. In total, six chest tubes were inserted but massive air leak persisted and his respiratory condition deteriorated due to bronchopneumonia and sepsis. The patient was transferred to Belgium. As a last resort, bilateral LVRS was performed through a median sternotomy. The most diseased areas of the upper lobes containing the air leak were resected bilaterally and a pleurectomy was associated. Three months after operation, there was a remarkable improvement in spirometric values with an increase in forced expiratory volume in one second of almost 100%. The results were sustained after a follow-up of 18 months. In this dramatic case, lung volume reduction surgery proved to be effective, and was even a life saving procedure.

An unusual poisoning with the unusual pesticide amitraz

Amitraz, 1,5 di-(2,4-dimethylphenyl)-3-methyl-1,3,5-triaza-penta-1,4-diene, a formamidine pesticide, is used worldwide. It causes side-effects in animals that resemble those caused by pure alpha 2-adrenergic agonist drugs such as clonidine. Data on poisonings in humans are scanty. We report on a case of human poisoning with amitraz with typical signs of alpha 2-adrenoreceptor stimulation.

High levels of leukaemia inhibitory factor in ARDS

Although elevated concentrations of a few cytokines have been shown to be present in the bronchoalveolar lavage (BAL) fluid (BALF) of patients with the acute (adult) respiratory distress syndrome (ARDS), the pathogenesis of ARDS is largely unknown. Leukaemia inhibitory factor (LIF), a growth factor recently recognised as a polyfunctional cytokine integrated in cytokine networks was measured in unconcentrated BALF of patients from different patient groups. LIF was measured in BALF by means of a specific and sensitive ELISA (detection limit 10 pg/ml) in BALF (lavage of 3 x 50 ml in the right middle lobe). LIF was not detected in the BALF of 13 healthy control patients and in only one (34 pg/ml) out of 25 patients at risk for ARDS (after cardiopulmonary bypass surgery) who underwent BAL 4 h after the end of the extracorporeal circulation. High and detectable levels were found in the unconcentrated BALF of 10 out of 12 patients with full-blown ARDS (212 +/- 116, mean +/- SEM, range 10-985 pg/ml). There was a good correlation between the level of LIF in the BALF and a number of markers of inflammation such as neutrophils/ml, albumin and protein levels. The biological role of LIF in these BALFs is not readily explained by its currently known actions and it is unknown whether LIF contributes to or is a response to local tissue damage. Our results indicate that this cytokine is part of the inflammatory cytokine cascade in ARDS.

N-acetylcysteine pretreatment of cardiac surgery patients influences plasma neutrophil elastase and neutrophil influx in bronchoalveolar lavage fluid

OBJECTIVE

Study of leukocyte activation and release of toxic mediators during extracorporeal circulation (ECC). ECC can be used to study the potential protective effect of a pharmacon against neutrophil-mediated lung injury. Clinical studies have indicated that N-acetylcysteine (NAC) may improve systemic oxygenation and reduce the need for ventilatory support when given to patients with acute lung injury.

DESIGN

Cardiac surgery patients were pretreated with high-dose NAC in order to assess the potential role of NAC to interfere with neutrophil-mediated inflammation and lung injury.

PATIENTS

18 patients who underwent ECC: group 1 (n = 8) no premedication (only placebo); group 2 (n = 10) NAC (72 mg/kg i.v. as a bolus, later 72 mg/kg over 12 h).

MEASUREMENTS AND RESULTS

In group 2, the partial pressure of oxygen in arterial blood/fractional inspired oxygen 4 h after surgery was significantly higher than in group 1 (213 +/- 31 vs 123 +/- 22; p = 0.044). NAC pretreatment prevented an increase in plasma neutrophil elastase activity (18.9 +/- 6.9 vs 49.9 +/- 5.6 ng/ml in group 1 at the end of ECC; p = 0.027). Release of myeloperoxidase (MPO) was not affected (group 1:1105 +/- 225 ng/ml vs group 2:1127 +/- 81 at the end of ECC; p = 0.63). At the end of ECC, total antigenic human neutrophil elastase (group 1:671 +/- 72 ng/ml vs group 2:579 +/- 134; p = 0.37) and complex formation between elastase and alpha 1-proteinase inhibitor were no different in the two groups. There were no significant difference in cellular composition and mediators in the lavage fluid, although values for total number of neutrophils, elastase, MPO and interleukin-8 were lower in group 2.

CONCLUSION

Pretreatment with NAC may prevent lung injury by diminishing elastase activity. Since the release of mediators, especially MPO, is not affected, this diminished activity of elastase may be achieved by enhanced inactivation by antiproteases after initial treatment.

Acute poisoning with amphetamines (MDEA) and heroin: antagonistic effects between the two drugs

A case of oral ingestion of large doses of both the amphetamine-derivative 3,4-methylene dioxyethamphetamine (MDEA) and heroin is reported. Despite high serum levels of both drugs, the patient did not present with the classic signs and symptoms normally seen during intoxication with these drugs. The patient recovered after symptomatic treatment. The possibility that opposite pharmacological properties of the two drugs prevented the patients death is discussed.

Dual effects of oxidized low-density lipoprotein on immune-stimulated nitric oxide and prostaglandin release in macrophages

Oxidized low-density lipoprotein (LDL) is currently regarded as a tentative key player in atherosclerosis by virtue of its ability to induce intracellular lipid accumulation and to modulate cell functions in the vessel wall. We previously demonstrated that inducible nitric oxide (NO) synthase activity is attenuated in lipid-laden J774 macrophages obtained by incubation with oxidized LDL 200 micrograms ml-1 for 24 h. In the present study we investigated the effect of oxidized LDL in a lower concentration (20 micrograms ml-1) or for a shorter time (6 h) and the possible mediator role of prostaglandin E2 and prostacyclin. Prostaglandins and the NO synthase metabolites citrulline and nitrite were elevated in the 24 h supernatant after immune stimulation with interferon-gamma 100 U ml-1 with or without lipopolysaccharide 10 micrograms ml-1. Pretreatment with oxidized LDL 20 micrograms ml-1 for 18 h decreased nitrite release by 31 +/- 2%, whereas prostaglandin production was not affected. A 6 h pre-exposure to 200 micrograms ml-1 had an opposite effect: it significantly potentiated interferon-gamma-stimulated prostaglandin E2 (10-fold), prostacyclin (7-fold), nitrite (1.5-fold), and citrulline (2.4-fold) release. Indomethacin 10 microM abolished the prostaglandin production and largely prevented the oxidized LDL-dependent increase in NO synthase activity. Acetylated LDL was without effect. The data show that the immune-induced release of NO is potentiated or suppressed, depending on the conditions of exposure to oxidized LDL. The potentiation due to short, high-dose exposure is partly mediated by prostaglandins since indomethacin inhibited both processes.

Epithelial modulation of cholinergic responses in rabbit trachea is partly due to neutral endopeptidase activity

By the simultaneous measurement of acetylcholine release and smooth muscle contraction in rabbit tracheal segments with and without epithelium, pre- as well as postsynaptic effects of this cell layer were studied on cholinergic neurotransmission. The epithelial cell layer exerted a presynaptic inhibitory influence on acetylcholine release, induced by KCl and electrical stimulation, with a concomitant decrease in the smooth muscle contractions. The responses elicited by exogenous acetylcholine, acting postsynaptically, were also inhibited in the presence of the epithelium. The epithelial effect was not accounted for by the production of inhibitory prostaglandins or a nitric oxide-synthase product. Furthermore, the epithelium did not function as a metabolic site for the degradation of acetylcholine. Phosphoramidon, an inhibitor of neutral endopeptidase, mimicked the effects of epithelium removal on the cholinergic responses to high frequency stimulation and on the acetylcholine-induced effects. Neutral endopeptidase inhibition did not further enhance the responses in epithelium-denuded segments. We therefore suggest that the inhibitory function of the epithelium can be partly explained by the activity of neutral endopeptidase, limiting the excitatory effects of tachykinins on cholinergic responses. An alteration in the neutral endopeptidase activity as a result of inflammatory responses and epithelial damage can contribute to the mechanism of airway hyperreactivity in asthma.