Renal replacement therapy initiation strategies in comatose patients with severe acute kidney injury: a secondary analysis of a multicenter randomized controlled trial

PURPOSE

The effect of renal replacement therapy (RRT) in comatose patients with acute kidney injury (AKI) remains unclear. We compared two RRT initiation strategies on the probability of awakening in comatose patients with severe AKI.

METHODS

We conducted a post hoc analysis of a trial comparing two delayed RRT initiation strategies in patients with severe AKI. Patients were monitored until they had oliguria for more than 72 h and/or blood urea nitrogen higher than 112 mg/dL and then randomized to a delayed strategy (RRT initiated after randomization) or a more-delayed one (RRT initiated if complication occurred or when blood urea nitrogen exceeded 140 mg/dL). We included only comatose patients (Richmond Agitation-Sedation scale [RASS] < - 3), irrespective of sedation, at randomization. A multi-state model was built, defining five mutually exclusive states: death, coma (RASS < - 3), incomplete awakening (RASS [- 3; - 2]), awakening (RASS [- 1; + 1] two consecutive days), and agitation (RASS >  + 1). Primary outcome was the transition from coma to awakening during 28 days after randomization.

RESULTS

A total of 168 comatose patients (90 delayed and 78 more-delayed) underwent randomization. The transition intensity from coma to awakening was lower in the more-delayed group (hazard ratio [HR] = 0.36 [0.17-0.78]; p = 0.010). Time spent awake was 10.11 days [8.11-12.15] and 7.63 days [5.57-9.64] in the delayed and the more-delayed groups, respectively. Two sensitivity analyses were performed based on sedation status and sedation practices across centers, yielding comparable results.

CONCLUSION

In comatose patients with severe AKI, a more-delayed RRT initiation strategy resulted in a lower chance of transitioning from coma to awakening.

Long-term outcomes after severe acute kidney injury in critically ill patients: the SALTO study

BACKGROUND

The extent of the consequences of an episode of severe acute kidney injury (AKI) on long-term outcome of critically ill patients remain debated. We conducted a prospective follow-up of patients included in a large multicenter clinical trial of renal replacement therapy (RRT) initiation strategy during severe AKI (the Artificial Kidney Initiation in Kidney Injury, AKIKI) to investigate long-term survival, renal outcome and health related quality of life (HRQOL). We also assessed the influence of RRT initiation strategy on these outcomes.

RESULTS

Follow-up of patients extended from 60 days to a median of 3.35 years [interquartile range (IQR), 1.89 to 4.09] after the end of initial study. Of the 619 patients included in the AKIKI trial, 316 survived after 60 days. The overall survival rate at 3 years from inclusion was 39.4% (95% CI 35.4 to 43.4). A total of 46 patients (on the 175 with available data on long-term kidney function) experienced worsening of renal function (WRF) at the time of follow-up [overall incidence of 26%, cumulative incidence at 4 years: 20.6% (CI 95% 13.0 to 28.3)]. Fifteen patients required chronic dialysis (5% of patients who survived after day 90). Among the 226 long-term survivors, 80 (35%) answered the EQ-5D questionnaire. The median index value reported was 0.67 (IQR 0.40 to 1.00) indicating a noticeable alteration of quality of life. Initiation strategy for RRT had no effect on any long-term outcome.

CONCLUSION

Severe AKI in critically ill patients was associated with a high proportion of death within the first 2 months but less so during long-term follow-up. A quarter of long-term survivors experienced a WRF and suffered from a noticeable impairment of quality of life. Renal replacement therapy initiation strategy was not associated with mortality outcome.

Nicotine patches in patients on mechanical ventilation for severe COVID-19: a randomized, double-blind, placebo-controlled, multicentre trial

Purpose

Epidemiologic studies have documented lower rates of active smokers compared to former or non-smokers in symptomatic patients affected by coronavirus disease 2019 (COVID-19). We assessed the efficacy and safety of nicotine administered by a transdermal patch in critically ill patients with COVID-19 pneumonia.

Methods

In this multicentre, double-blind, placebo-controlled trial conducted in 18 intensive care units in France, we randomly assigned adult patients (non-smokers, non-vapers or who had quit smoking/vaping for at least 12 months) with proven COVID-19 pneumonia receiving invasive mechanical ventilation for up to 72 h to receive transdermal patches containing either nicotine at a daily dose of 14 mg or placebo until 48 h following successful weaning from mechanical ventilation or for a maximum of 30 days, followed by 3-week dose tapering by 3.5 mg per week. Randomization was stratified by centre, non- or former smoker status and Sequential Organ Function Assessment score (< or ≥ 7). The primary outcome was day-28 mortality. Main prespecified secondary outcomes included 60-day mortality, time to successful extubation, days alive and free from mechanical ventilation, renal replacement therapy, vasopressor support or organ failure at day 28.

Results

Between November 6th 2020, and April 2nd 2021, 220 patients were randomized from 18 active recruiting centers. After excluding 2 patients who withdrew consent, 218 patients (152 [70%] men) were included in the analysis: 106 patients to the nicotine group and 112 to the placebo group. Day-28 mortality did not differ between the two groups (30 [28%] of 106 patients in the nicotine group vs 31 [28%] of 112 patients in the placebo group; odds ratio 1.03 [95% confidence interval, CI 0.57–1.87]; p = 0.46). The median number of day-28 ventilator-free days was 0 (IQR 0–14) in the nicotine group and 0 (0–13) in the placebo group (with a difference estimate between the medians of 0 [95% CI -3–7]). Adverse events likely related to nicotine were rare (3%) and similar between the two groups.

Conclusion

In patients having developed severe COVID-19 pneumonia requiring invasive mechanical ventilation, transdermal nicotine did not significantly reduce day-28 mortality. There is no indication to use nicotine in this situation.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00134-022-06721-1.

High Heterogeneity of Temporal Bone CT Aspects in Osteogenesis Imperfecta Is Not Linked to Hearing Loss

OBJECTIVES

To determine whether temporal bone computed tomography (CT) features are linked to the presence and type of hearing loss in osteogenesis imperfecta (OI) when considering hearing-impaired OI patients and normally hearing (NH) OI ones. A secondary objective was to assess whether other factors influence CT features in a large sample: age, type of mutation, or bone mineral density (BMD).

METHODS

A total of 41 adults with OI underwent CTs and pure-tone audiometry in 82 ears. Hearing thresholds were normal in 64 out of 82 ears, and most had not been operated on for stapedectomy or stapedotomy. Ossicle density, footplates, oval and round windows, retrofenestral peri- and endolabyrinths, and temporal pneumatization were analyzed twice by an experienced radiologist. CT features were compared to hearing, age, collagen mutations, and bone mineral density.

RESULTS

Unexpectedly a high prevalence of footplate, ossicle, and otic capsule anomalies was observed, even in NH ears. Footplate hypodensity or thickening was mostly found in ears without conductive hearing loss. There were significantly more retrofenestral anomalies or window obstruction in ears with a sensorineural hearing loss component than in ears without. Age was significantly higher in ears with middle layer hypodensity than in ears without. Patients with mutations were expected to have reduced collagen quantity and had significantly more footplate or retrofenestral anomalies than those with qualitative mutations. BMD was significantly higher in ears without temporal hyperpneumatization.

CONCLUSION

Temporal bone CT features in OI are present in a large proportion of patients, had they hearing loss or not, and might be determined more by collagen mutation type than by age or BMD.

Continuous renal replacement therapy versus intermittent hemodialysis as first modality for renal replacement therapy in severe acute kidney injury: a secondary analysis of AKIKI and IDEAL-ICU studies

Background

Intermittent hemodialysis (IHD) and continuous renal replacement therapy (CRRT) are the two main RRT modalities in patients with severe acute kidney injury (AKI). Meta-analyses conducted more than 10 years ago did not show survival difference between these two modalities. As the quality of RRT delivery has improved since then, we aimed to reassess whether the choice of IHD or CRRT as first modality affects survival of patients with severe AKI.

Methods

This is a secondary analysis of two multicenter randomized controlled trials (AKIKI and IDEAL-ICU) that compared an early RRT initiation strategy with a delayed one. We included patients allocated to the early strategy in order to emulate a trial where patients would have been randomized to receive either IHD or CRRT within twelve hours after the documentation of severe AKI. We determined each patient’s modality group as the first RRT modality they received. The primary outcome was 60-day overall survival. We used two propensity score methods to balance the differences in baseline characteristics between groups and the primary analysis relied on inverse probability of treatment weighting.

Results

A total of 543 patients were included. Continuous RRT was the first modality in 269 patients and IHD in 274. Patients receiving CRRT had higher cardiovascular and total-SOFA scores. Inverse probability weighting allowed to adequately balance groups on all predefined confounders. The weighted Kaplan–Meier death rate at day 60 was 54·4% in the CRRT group and 46·5% in the IHD group (weighted HR 1·26, 95% CI 1·01–1·60). In a complementary analysis of less severely ill patients (SOFA score: 3–10), receiving IHD was associated with better day 60 survival compared to CRRT (weighted HR 1.82, 95% CI 1·01–3·28; p < 0.01). We found no evidence of a survival difference between the two RRT modalities in more severe patients.

Conclusion

Compared to IHD, CRRT as first modality seemed to convey no benefit in terms of survival or of kidney recovery and might even have been associated with less favorable outcome in patients with lesser severity of disease. A prospective randomized non-inferiority trial should be implemented to solve the persistent conundrum of the optimal RRT technique.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13054-022-03955-9.

Vascular access for renal replacement therapy among 459 critically ill patients: a pragmatic analysis of the randomized AKIKI trial

BACKGROUND

Vascular access for renal replacement therapy (RRT) is routine question in the intensive care unit. Randomized trials comparing jugular and femoral sites have shown similar rate of nosocomial events and catheter dysfunction. However, recent prospective observational data on RRT catheters use are scarce. We aimed to assess the site of RRT catheter, the reasons for catheter replacement, and the complications according to site in a large population of critically ill patients with acute kidney injury.

PATIENTS AND METHODS

We performed an ancillary study of the AKIKI study, a pragmatic randomized controlled trial, in which patients with severe acute kidney injury (KDIGO 3 classification) with invasive mechanical ventilation, catecholamine infusion or both were randomly assigned to either an early or a delayed RRT initiation strategy. The present study involved all patients who underwent at least one RRT session. Number of RRT catheters, insertion sites, factors potentially associated with the choice of insertion site, duration of catheter use, reason for catheter replacement, and complications were prospectively collected.

RESULTS

Among the 619 patients included in AKIKI, 462 received RRT and 459 were finally included, with 598 RRT catheters. Femoral site was chosen preferentially (n = 319, 53%), followed by jugular (n = 256, 43%) and subclavian (n = 23, 4%). In multivariate analysis, continuous RRT modality was significantly associated with femoral site (OR = 2.33 (95% CI (1.34-4.07), p = 0.003) and higher weight with jugular site [88.9 vs 83.2 kg, OR = 0.99 (95% CI 0.98-1.00), p = 0.03]. Investigator site was also significantly associated with the choice of insertion site (p = 0.03). Cumulative incidence of catheter replacement did not differ between jugular and femoral site [sHR 0.90 (95% CI 0.64-1.25), p = 0.67]. Catheter dysfunction was the main reason for replacement (n = 47), followed by suspected infection (n = 29) which was actually seldom proven (n = 4). No mechanical complication (pneumothorax or hemothorax) occurred.

CONCLUSION

Femoral site was preferentially used in this prospective study of RRT catheters in 31 French intensive care units. The choice of insertion site depended on investigating center habits, weight, RRT modality. A high incidence of catheter infection suspicion led to undue replacement.

Comparison of two delayed strategies for renal replacement therapy initiation for severe acute kidney injury (AKIKI 2): a multicentre, open-label, randomised, controlled trial

BACKGROUND

Delaying renal replacement therapy (RRT) for some time in critically ill patients with severe acute kidney injury and no severe complication is safe and allows optimisation of the use of medical devices. Major uncertainty remains concerning the duration for which RRT can be postponed without risk. Our aim was to test the hypothesis that a more-delayed initiation strategy would result in more RRT-free days, compared with a delayed strategy.

METHODS

This was an unmasked, multicentre, prospective, open-label, randomised, controlled trial done in 39 intensive care units in France. We monitored critically ill patients with severe acute kidney injury (defined as Kidney Disease: Improving Global Outcomes stage 3) until they had oliguria for more than 72 h or a blood urea nitrogen concentration higher than 112 mg/dL. Patients were then randomly assigned (1:1) to either a strategy (delayed strategy) in which RRT was started just after randomisation or to a more-delayed strategy. With the more-delayed strategy, RRT initiation was postponed until mandatory indication (noticeable hyperkalaemia or metabolic acidosis or pulmonary oedema) or until blood urea nitrogen concentration reached 140 mg/dL. The primary outcome was the number of days alive and free of RRT between randomisation and day 28 and was done in the intention-to-treat population. The study is registered with ClinicalTrial.gov, NCT03396757 and is completed.

FINDINGS

Between May 7, 2018, and Oct 11, 2019, of 5336 patients assessed, 278 patients underwent randomisation; 137 were assigned to the delayed strategy and 141 to the more-delayed strategy. The number of complications potentially related to acute kidney injury or to RRT were similar between groups. The median number of RRT-free days was 12 days (IQR 0-25) in the delayed strategy and 10 days (IQR 0-24) in the more-delayed strategy (p=0·93). In a multivariable analysis, the hazard ratio for death at 60 days was 1·65 (95% CI 1·09-2·50, p=0·018) with the more-delayed versus the delayed strategy. The number of complications potentially related to acute kidney injury or renal replacement therapy did not differ between groups.

INTERPRETATION

In severe acute kidney injury patients with oliguria for more than 72 h or blood urea nitrogen concentration higher than 112 mg/dL and no severe complication that would mandate immediate RRT, longer postponing of RRT initiation did not confer additional benefit and was associated with potential harm.

FUNDING

Programme Hospitalier de Recherche Clinique.

[Gynecological Lemierre's syndrome: A case report and literature review]

INTRODUCTION

Lemierre's syndrome is defined as an oropharyngeal infection due to Fusobacterium necrophorum, associated with septic thrombophlebitis of the internal jugular vein. The uncommon pelvic variant of the syndrome is a rare condition, poorly described in literature.

CASE REPORT

We report a case of gynecological Lemierre's syndrome in a 19-year-old woman after a first sexual intercourse, who presented acute respiratory failure, left internal iliac vein thrombosis with pulmonary embolism, in the setting of salpingitis and F. necrophorum bacteriemia.

CONCLUSION

Gynecological Lemierre's syndrome is a rare and unrecognized condition, which could be lethal. Early recognition of the disorder enables initiation of appropriate antibiotic therapy for 4 to 6 weeks, and discussion of anticoagulant therapy which indications are not yet well defined.

The Artificial Kidney Initiation in Kidney Injury 2 (AKIKI2): study protocol for a randomized controlled trial

BACKGROUND

The Artificial Kidney Initiation in Kidney Injury (AKIKI) trial showed that a delayed renal replacement therapy (RRT) strategy for severe acute kidney injury (AKI) in critically ill patients was safe and associated with major reduction in RRT initiation compared with an early strategy. The five criteria which mandated RRT initiation in the delayed arm were: severe hyperkalemia, severe acidosis, acute pulmonary edema due to fluid overload resulting in severe hypoxemia, serum urea concentration > 40 mmol/l and oliguria/anuria > 72 h. However, duration of anuria/oliguria and level of blood urea are still criteria open to debate. The objective of the study is to compare the delayed strategy used in AKIKI (now termed "standard") with another in which RRT is further delayed for a longer period (termed "delayed strategy").

METHODS/DESIGN

This is a prospective, multicenter, open-label, two-arm randomized trial. The study is composed of two stages (observational and randomization stages). At any time, the occurrence of a potentially severe condition (severe hyperkalemia, severe metabolic or mixed acidosis, acute pulmonary edema due to fluid overload resulting in severe hypoxemia) suggests immediate RRT initiation. Patients receiving (or who have received) intravenously administered catecholamines and/or invasive mechanical ventilation and presenting with AKI stage 3 of the KDIGO classification and with no potentially severe condition are included in the observational stage. Patients presenting a serum urea concentration > 40 mmol/l and/or an oliguria/anuria for more than 72 h are randomly allocated to a standard (RRT is initiated within 12 h) or a delayed RRT strategy (RRT is initiated only if an above-mentioned potentially severe condition occurs or if the serum urea concentration reaches 50 mmol/l). The primary outcome will be the number of RRT-free days at day 28. One interim analysis is planned. It is expected to include 810 patients in the observational stage and to randomize 270 subjects.

DISCUSSION

The AKIKI2 study should improve the knowledge of RRT initiation criteria in critically ill patients. The potential reduction in RRT use allowed by a delayed RRT strategy might be associated with less invasive care and decreased costs. Enrollment is ongoing. Inclusions are expected to be completed by November 2019.

TRIAL REGISTRATION

ClinicalTrials.gov, ID: NCT03396757. Registered on 11 January 2018.

Timing of Renal Support and Outcome of Septic Shock and Acute Respiratory Distress Syndrome. A Post Hoc Analysis of the AKIKI Randomized Clinical Trial

RATIONALE

The optimal strategy for initiation of renal replacement therapy (RRT) in patients with severe acute kidney injury in the context of septic shock and acute respiratory distress syndrome (ARDS) is unknown.

OBJECTIVES

To examine the effect of an early compared with a delayed RRT initiation strategy on 60-day mortality according to baseline sepsis status, ARDS status, and severity.

METHODS

Post hoc analysis of the AKIKI (Artificial Kidney Initiation in Kidney Injury) trial.

MEASUREMENTS AND MAIN RESULTS

Subgroups were defined according to baseline characteristics: sepsis status (Sepsis-3 definition), ARDS status (Berlin definition), Simplified Acute Physiology Score 3 (SAPS 3), and Sepsis-related Organ Failure Assessment (SOFA). Of 619 patients, 348 (56%) had septic shock and 207 (33%) had ARDS. We found no significant influence of the baseline sepsis status (P = 0.28), baseline ARDS status (P = 0.94), and baseline severity scores (P = 0.77 and P = 0.46 for SAPS 3 and SOFA, respectively) on the comparison of 60-day mortality according to RRT initiation strategy. A delayed RRT initiation strategy allowed 45% of patients with septic shock and 46% of patients with ARDS to escape RRT. Urine output was higher in the delayed group. Renal function recovery occurred earlier with the delayed RRT strategy in patients with septic shock or ARDS (P < 0.001 and P = 0.003, respectively). Time to successful extubation in patients with ARDS was not affected by RRT strategy (P = 0.43).

CONCLUSIONS

Early RRT initiation strategy was not associated with any improvement of 60-day mortality in patients with severe acute kidney injury and septic shock or ARDS. Unnecessary and potentially risky procedures might often be avoided in these fragile populations. Clinical trial registered with www.clinicaltrials.gov (NCT 01932190).

Initiation Strategies for Renal-Replacement Therapy in the Intensive Care Unit

BACKGROUND

The timing of renal-replacement therapy in critically ill patients who have acute kidney injury but no potentially life-threatening complication directly related to renal failure is a subject of debate.

METHODS

In this multicenter randomized trial, we assigned patients with severe acute kidney injury (Kidney Disease: Improving Global Outcomes [KDIGO] classification, stage 3 [stages range from 1 to 3, with higher stages indicating more severe kidney injury]) who required mechanical ventilation, catecholamine infusion, or both and did not have a potentially life-threatening complication directly related to renal failure to either an early or a delayed strategy of renal-replacement therapy. With the early strategy, renal-replacement therapy was started immediately after randomization. With the delayed strategy, renal-replacement therapy was initiated if at least one of the following criteria was met: severe hyperkalemia, metabolic acidosis, pulmonary edema, blood urea nitrogen level higher than 112 mg per deciliter, or oliguria for more than 72 hours after randomization. The primary outcome was overall survival at day 60.

RESULTS

A total of 620 patients underwent randomization. The Kaplan-Meier estimates of mortality at day 60 did not differ significantly between the early and delayed strategies; 150 deaths occurred among 311 patients in the early-strategy group (48.5%; 95% confidence interval [CI], 42.6 to 53.8), and 153 deaths occurred among 308 patients in the delayed-strategy group (49.7%, 95% CI, 43.8 to 55.0; P=0.79). A total of 151 patients (49%) in the delayed-strategy group did not receive renal-replacement therapy. The rate of catheter-related bloodstream infections was higher in the early-strategy group than in the delayed-strategy group (10% vs. 5%, P=0.03). Diuresis, a marker of improved kidney function, occurred earlier in the delayed-strategy group (P<0.001).

CONCLUSIONS

In a trial involving critically ill patients with severe acute kidney injury, we found no significant difference with regard to mortality between an early and a delayed strategy for the initiation of renal-replacement therapy. A delayed strategy averted the need for renal-replacement therapy in an appreciable number of patients. (Funded by the French Ministry of Health; ClinicalTrials.gov number, NCT01932190.).

Comparison of two strategies for initiating renal replacement therapy in the intensive care unit: study protocol for a randomized controlled trial (AKIKI)

BACKGROUND

There is currently no validated strategy for the timing of renal replacement therapy (RRT) for acute kidney injury (AKI) in the intensive care unit (ICU) when short-term life-threatening metabolic abnormalities are absent. No adequately powered prospective randomized study has addressed this issue to date. As a result, significant practice heterogeneity exists and may expose patients to either unnecessary hazardous procedures or undue delay in RRT.

METHODS/DESIGN

This is a multicenter, prospective, randomized, open-label parallel-group clinical trial that compares the effect of two RRT initiation strategies on overall survival of critically ill patients receiving intravenous catecholamines or invasive mechanical ventilation and presenting with AKI classification stage 3 (KDIGO 2012). In the 'early' strategy, RRT is initiated immediately. In the 'delayed' strategy, clinical and metabolic conditions are closely monitored and RRT is initiated only when one or more events (severity criteria) occur, including: oliguria or anuria for more than 72 hours after randomization, serum urea concentration >40 mmol/l, serum potassium concentration >6 mmol/l, serum potassium concentration >5.5 mmol/l persisting despite medical treatment, arterial blood pH <7.15 in a context of pure metabolic acidosis (PaCO2 < 35 mmHg) or in a context of mixed acidosis with a PaCO2 ≥ 50 mmHg without possibility of increasing alveolar ventilation, acute pulmonary edema due to fluid overload despite diuretic therapy leading to severe hypoxemia requiring oxygen flow rate >5 l/min to maintain SpO2 > 95% or FiO2 > 50% under invasive or noninvasive mechanical ventilation. The primary outcome measure is overall survival, measured from randomization (D0) until death, regardless of the cause. The minimum follow-up duration for each patient will be 60 days. Two interim analyses are planned, blinded to group allocation. It is expected that there will be 620 subjects in all.

DISCUSSION

The AKIKI study will be one of the very few large randomized controlled trials evaluating mortality according to the timing of RRT in critically ill patients with AKI classification stage 3 (KDIGO 2012). Results should help clinicians decide when to initiate RRT.

TRIAL REGISTRATION

ClinicalTrials.gov NCT01932190.

Bone marrow-derived and synovium-derived mesenchymal cells promote Th17 cell expansion and activation through caspase 1 activation: contribution to the chronicity of rheumatoid arthritis

OBJECTIVE

Th17 cells have been implicated in rheumatoid arthritis (RA). We hypothesized that the interaction of T cells with bone marrow-derived mesenchymal stem cells (BM-MSCs) or with fibroblast- like synoviocytes (FLS) might, with the help of T cell-secreted inflammatory cytokines (i.e., interleukin-17A [IL-17A], tumor necrosis factor α [TNFα], and/or interferon-γ [IFNγ]), promote Th17 cell expansion and activation.

METHODS

Peripheral blood mononuclear cells (PBMCs) from healthy blood donors were cocultured with BM-MSCs or FLS from RA patients or osteoarthritis (OA) patients. Cocultures were exposed to phytohemagglutinin with or without IL-17A, TNFα, or IFNγ. Quantitative reverse transcription-polymerase chain reaction analysis, enzyme-linked immunosorbent assay, and cytofluorometry were used to measure IL-17A production.

RESULTS

Interaction of PBMCs with BM-MSCs inhibited Th1 and Th2 responses, but promoted Th17 cell expansion, as early as 24 hours, as demonstrated by increases in retinoic acid receptor-related orphan nuclear receptor γ or IL-17A messenger RNA (mRNA) levels, IL-17A secretion levels, and IL-17A-secreting cell frequency, as well as by T cell switching to the Th17 pathway after 2 rounds of stimulation with MSCs. IL-17A production was also increased in PBMCs stimulated with anti-CD3 plus anti-CD28 or in isolated CD3+ or CD45RO+ T cells, thus demonstrating the role of T cell activation. Levels of mRNA for IL-6, IL-8, and IL-1β were further amplified when T cell-secreted inflammatory cytokines were added. Interestingly, OA FLS or RA FLS also enhanced IL-17A and IL-6 production, but only RA FLS enhanced IFNγ and IL-1β production. We further demonstrated that MSC-mediated Th17 promotion requires caspase 1 activation by using an inhibitory peptide and measuring its activity.

CONCLUSION

We found that the interaction of MSCs or FLS with T cells promotes the activation and expansion of Th17 cells through caspase 1 activation. Since proinflammatory and T cell-secreted inflammatory cytokines are also amplified, this mechanism may participate in the chronicity of RA.

Beneficial effects of loxapine on agitation and breathing patterns during weaning from mechanical ventilation

INTRODUCTION

Interruption of sedation during weaning from mechanical ventilation often leads to patient agitation because of withdrawal syndrome. We tested the short-term efficacy and tolerance of loxapine in this situation.

METHODS

Nineteen mechanically ventilated patients with marked agitation after sedation withdrawal were included. Three agitation scales, the Richmond Agitation Sedation Scale (RASS), the Motor Activity Assessment Scale (MAAS), and the Ramsay and physiological variables (respiratory rate, airway occlusion pressure during the first 0.1 second of inspiration (P0.1), heart rate and systolic arterial blood pressure) were recorded before and after loxapine administration.

RESULTS

Loxapine dramatically improved all agitation scores (RASS and MASS decreased from 2 +/- 0 to -1.1 +/- 2.3, and 5.4 +/- 0.5 to 2.7 +/- 1.6, respectively; Ramsay increased from 1.0 +/- 0 to 3.5 +/- 1.5, 60 minutes after loxapine administration, P < 0.05 for all scores) as well as P0.1 (6 +/- 4.2 to 1.8 +/- 1.8 cm H2O; P < 0.05) and respiratory rate (from 31.2 +/- 7.2 to 23.4 +/- 7.8; P < 0.05) without hemodynamic adverse events. No side effects occurred. Sixteen (84%) patients were successfully managed with loxapine, sedation was resumed in two others, and one patient self-extubated without having to be reintubated.

CONCLUSIONS

Loxapine was safe and effective in treating agitation in a small group of mechanically ventilated patients and improved respiratory physiologic parameters, enabling the weaning process to be pursued. A multicenter trial is under way to confirm these promising results.

Increased cartilage type II collagen degradation in patients with osteogenesis imperfecta used as a human model of bone type I collagen alterations

OBJECTIVE

We investigated whether cartilage degradation is altered in adult patients with mild osteogenesis imperfecta (OI) used as a human model of bone type I collagen-related osteoarthritis (OA).

PATIENTS AND METHODS

Sixty-four adult patients with OI (39% women, mean age+/-SD: 37+/-12 years) and 64 healthy age-matched controls (54% women, 39+/-7 years) were included. We also compared data in 87 patients with knee OA (73% women, 63+/-8 years, mean disease duration: 6 years) and 291 age-matched controls (80% women, 62+/-10 years). Urinary C-terminal cross-linked telopeptide of type II collagen (CTX-II), a marker of cartilage degradation, urinary helical peptide of type I collagen (Helix-I), a marker of bone resorption, and the urinary ratio between non-isomerised/isomerised (alpha/beta CTX-I) type I collagen C-telopeptide, a marker of type I collagen maturation, were measured.

RESULTS

Patients with OI had CTX-II levels similar to those of subjects with knee OA (p=0.89; mean+/-SEM; 460+/-57 ng/mmol Cr for OI group and 547+/-32 ng/mmol Cr for OA group) and significantly higher than both young (144+/-7.8 ng/mmol Cr, p<0.0001) and old controls (247+/-7 ng/mmol Cr, p<0.0001). In patients with OI, increased Helix-I (p<0.0001) and alpha/beta CTX-I (p=0.0067) were independently associated with increased CTX-II and together explained 26% of its variance (p< 0.0001). In patients with knee OA, increased levels of alpha/beta CTX-I ratio were also associated with higher CTX-II levels.

CONCLUSION

Adult patients with OI or knee OA are characterized by increased cartilage type II collagen degradation, which is associated with increased type I collagen degradation for OI and lower type I collagen maturation for both OI and OA. These data suggest that both quantitative and qualitative alterations of bone type I collagen metabolism are involved in increased cartilage degradation in patients with OI or knee OA.

Bone turnover and type I collagen C-telopeptide isomerization in adult osteogenesis imperfecta: associations with collagen gene mutations

INTRODUCTION

Increased bone fragility in osteogenesis imperfecta (OI) is not totally accounted for by decreased bone mineral density (BMD), and alterations of type I collagen (Col I) are believed to play a role. Newly synthesized Col I comprises non isomerized C-telopeptide (alphaCTX), but with bone matrix maturation alphaCTX is converted to its isomerized beta form (betaCTX). Urinary alpha/betaCTX ratio has been proposed to reflect collagen maturation. We investigated changes in bone turnover and Col I isomerization in adult patients with OI and their relationship with Col I gene mutations.

PATIENTS AND METHODS

Sixty four adult patients [25 women, 39 men mean age (SD): 36.2 (11.6) years] with OI participating in a randomized study and 64 healthy controls of similar age and gender distribution were investigated. In patients with OI and controls, we measured the following biochemical markers of bone metabolism: serum type I collagen N-propeptide (PINP) an index of Col I synthesis, osteocalcin a marker of osteoblastic activity, urinary Col I helical peptide, a marker reflecting the degradation of the helical portion of Col I, urinary alphaCTX and urinary and serum betaCTX. Based on the putative functional effects of Col I gene mutations which were identified in 56 OI subjects, patients were divided in those with haploinsufficiency (n=29), patients presenting with helical domain alterations (n=17) and others (n=10).

RESULTS

Compared to healthy controls, patients with OI had decreased levels of PINP (-22.7%, p<0.0001), increased osteocalcin (+73%, p<0.0001) and increased Col I helical peptide (+58%, p=0.0007). Urinary alphaCTX was increased (+31%, p=0.03) whereas urinary (-15%, p=0.022) and serum (-9.9%, p=0.0056) betaCTX were significantly decreased, resulting in a 49% (p<0.001) higher urinary alpha/betaCTX ratio. Patients with Col I gene mutations resulting in haploinsufficiency had lower PINP levels than patients with helical domain alterations (26.4+/-15.3 vs 41.6+/-27.4 ng/ml, p=0.0043) and controls (p<0.01).

CONCLUSION

Adults with OI are characterized by decreased Col I synthesis - especially those with haploinsufficiency mutations - increased Col I degradation and decreased Col I C-telopeptide isomerization.

Incidence and impact on clinical outcome of infections with piperacillin/tazobactam resistant Escherichia coli in ICU: a retrospective study

BACKGROUND

Escherichia coli infections are frequent in ICU patients. The increased resistance to fluoroquinolones and amoxicillin/clavulanate of this pathogen mandates the prescription of broad-spectrum antibiotics such as piperacillin/tazobactam (PIP-TAZ) or third generation cephalosporins (3GC).

METHODS

To assess incidence and impact on clinical outcome of infections with PIP-TAZ resistant E. coli in ICU patients, we conducted a retrospective cohort study with infections due to PIP-TAZ resistant (PIP-TAZ R) or to PIP-TAZ susceptible strains (PIP-TAZ S) between 1 January 2002 and 30 June 2004.

RESULTS

Of 83 strains, 13 were PIP-TAZ R: 2 strains produced an extended-spectrum beta-lactamase (2%), 11 produced a high level penicillinase (13%). Prior amoxicillin or amoxicillin/clavulanate prescription was reported in 7 cases (54%) of infections with PIP-TAZ R isolates and in 15 cases (21%) of infections with PIP-TAZ S isolates (p = 0.03). Time of onset of the infection from hospital admission was longer in case of infections with PIP-TAZ R than with PIP-TAZ S isolates (22 +/- 32 vs 10 +/- 21 days, p = 0.01). The overall ICU mortality rate was 38%. Mortality and length of stay in ICU were similar in case of infections with PIP-TAZ R isolates and with PIP-TAZ S isolates.

CONCLUSION

Infections with PIP-TAZ R E. coli are frequent in ICU patients. No prognostic impact of this pattern of resistance was found. Prescription of PIP-TAZ for empirical treatment of E. coli infections in ICU however exposes to inappropriate therapy.

Levels of vancomycin in cerebrospinal fluid of adult patients receiving adjunctive corticosteroids to treat pneumococcal meningitis: a prospective multicenter observational study

BACKGROUND

Evidence from a recent randomized controlled trial suggests that dexamethasone as adjunct therapy in adult pneumococcal meningitis reduces mortality and neurological sequelae. However, adding dexamethasone has the potential to reduce penetration of vancomycin into the cerebrospinal fluid (CSF). We sought to determine concentrations of vancomycin in serum and CSF of patients with suspected or proven pneumococcal meningitis receiving dexamethasone to assess the penetration of vancomycin into the CSF during steroid therapy.

METHODS

In an observational open multicenter study, adult patients admitted to the intensive care unit because of suspected pneumococcal meningitis received recommended treatment for pneumococcal meningitis, comprising intravenous cefotaxime (200 mg per kg of body weight per day), vancomycin (administered as continuous infusion of 60 mg per kg of body weight per day after a loading dose of 15 mg per kg of body weight), and adjunctive therapy with dexamethasone (10 mg every 6 h). Vancomycin levels in CSF were measured on day 2 or day 3 of therapy and were correlated with protein levels in CSF and vancomycin levels in serum (determined at the same time as levels in CSF).

RESULTS

Fourteen patients were included. Thirteen had proven pneumococcal meningitis; 1 patient, initially suspected of having pneumococcal meningitis, was finally determined to have meningitis due to Neisseria meningitidis. Mean levels of vancomycin in serum and CSF were 25.2 and 7.2 mg/L, respectively, and were positively correlated (r=0.6; P=.025). A positive correlation was also found between the ratio of vancomycin in CSF to vancomycin in serum and the level of protein in CSF (r=0.66; P=.01).

CONCLUSIONS

Appropriate concentrations of vancomycin in CSF may be obtained even when concomitant steroids are used. Dexamethasone can, therefore, be used without fear of impeding vancomycin penetration into the CSF of patients with pneumococcal meningitis, provided that vancomycin dosage is adequate. This study is registered at http://www.ClinicalTrials.gov/ (registration number NCT00162578).

Osteogenesis imperfecta: New treatment options

Classic treatments of osteogenesis imperfecta for children and adults include rehabilitation therapy and orthopedic surgery. New treatments include bisphosphonates. Among them, the effects of intravenous pamidronate have been primarily evaluated in children in several open cohorts. Treatments of adult patients are not established. Several other treatments may have an effect on the fracture rate. However, further studies are needed to demonstrate an effect on fracture rate in children and adult patients. A new approach has been developed to replace mutated genes using mesenchymal stem cells and a construct, which inactivates COL1A1.

Novel aspects on the contribution of T cells and dendritic cells in the pathogenesis of myositis

This review focuses on recent advances and new hypothesis in the understanding of the T and dendritic cells contribution to the pathogenesis of idiopathic inflammatory myopathies (IIMs), especially polymyositis (PM) and dermatomyositis (DM). The new data show that non-specific amplification of muscle inflammation by T lymphocyte and dendritic cells may result from the local production of cytokines and chemokines. Synergistic interactions between these factors explain some of the clinical features. The potent role of these molecules suggests their potential for therapeutic manipulation using specific inhibitors.

Effects of oral alendronate on BMD in adult patients with osteogenesis imperfecta: a 3-year randomized placebo-controlled trial

A 3-year, randomized, double-blind, placebo-controlled trial evaluated the effect of oral alendronate on the BMD of 64 adult patients with osteogenesis imperfecta. The mean increases in the lumbar spine BMD were 10.1 +/- 9.8% (p < 0.001) and 0.7 +/- 5.7% in the alendronate and placebo groups, respectively. Oral alendronate increases BMD in adult patients with osteogenesis imperfecta.

INTRODUCTION

This study evaluated the effect of oral alendronate on the BMD of adult patients with osteogenesis imperfecta.

MATERIALS AND METHODS

We carried out a 3-year, randomized, double-blind, placebo-controlled trial of oral alendronate in 64 adult patients with osteogenesis imperfecta. The primary endpoint was the difference between the groups in the mean percent change in lumbar spine BMD at 3 years. Secondary outcomes included changes in BMD of total hip, vertebral and peripheral fracture incidence, pain, hearing loss, and bone turnover biochemical markers. Patients were treated daily with either placebo or 10 mg alendronate. All received 1 g of calcium and 800 IU of vitamin D daily.

RESULTS

The mean +/- SD increases in the lumbar spine BMD were 10.1 +/- 9.8% (p < 0.001) and 0.7 +/- 5.7% in the alendronate and placebo groups, respectively. Hip BMD increased in the alendronate group by 3.3 +/- 0.5% (p = 0.001) and decreased in the placebo group by 0.3 +/- 0.6%. The sample size was not sufficient to determine an effect of alendronate on fracture rate. A significant increase of the pain score was noted in the alendronate group (p = 0.04) in the intent-to-treat analysis but not in the per protocol analysis. There was no change in hearing in either group. Bone resorption and formation biochemical markers were significantly decreased in the alendronate group (p < 0.001). There were no differences in severe adverse effects between the groups, but there was an increase in nonsevere upper gastrointestinal effects in the alendronate group (p = 0.003).

CONCLUSIONS

Oral alendronate increases BMD and increase nonsevere gastrointestinal adverse effects but does not modify the hearing loss in adult patients with osteogenesis imperfecta. More studies are needed to evaluate an effect on the fracture rate.

The role of neurotrophins in muscle under physiological and pathological conditions

This review summarizes the various effects of neurotrophins in skeletal muscle and how these proteins act as potential regulators of development, maintenance, function, and regeneration of skeletal muscle fibers. Increasing evidence suggests that this family of neurotrophic factors not only modulates survival and function of innervating motoneurons and proprioceptive neurons but also development and differentiation of myoblasts and muscle fibers. Neurotrophins and neurotrophin receptors play a role in the coordination of muscle innervation and functional differentiation of neuromuscular junctions. However, neurotrophin receptors are also expressed in differentiating muscle cells, in particular at early developmental stages in myoblasts before they fuse. In adults with pathological conditions such as human degenerative and inflammatory muscle disorders, variations of neurotrophin expression are found, but the role of neurotrophins under such conditions is still not clear. The goal of this review is to provide a basis for a better understanding and future studies on the role of these factors under such pathological conditions and for treatment of human muscle diseases.

Contribution of tumour necrosis factor alpha and interleukin (IL) 1beta to IL6 production, NF-kappaB nuclear translocation, and class I MHC expression in muscle cells: in vitro regulation with specific cytokine inhibitors

OBJECTIVE

To evaluate the effect of tumour necrosis factor alpha (TNFalpha), interleukin (IL) 1beta, and their respective inhibitors the p75 TNFalpha soluble receptor (sTNFR) and the type II sIL1betaR (sIL1RII) on whole muscle and isolated myoblast activation.

METHODS

Normal muscle samples were stimulated for 7 days with TNFalpha alone or in combination with IL1beta, and myoblasts from these samples for 48 hours. IL6 production was measured by ELISA. Nuclear translocation of NF-kappaB was analysed by immunofluorescent staining and class I MHC expression by FACS.

RESULTS

TNFalpha and IL1beta induced IL6 production by normal muscle samples and myoblasts, the action of TNFalpha being more potent on muscle samples. Their soluble receptors (1 microg/ml) decreased this production. Suboptimal concentrations of TNFalpha and IL1beta induced NF-kappaB translocation. sTNFR markedly down regulated TNFalpha-induced translocation while sIL1RII was less potent on IL1beta-induced activation. NF-kappaB translocation induced by the combination of optimal concentrations of TNFalpha and IL1beta was completely inhibited by their soluble receptors. TNFalpha and to a lesser extent IL1beta induced class I MHC expression by myoblasts and this effect was completely inhibited by their respective soluble receptors.

CONCLUSION

These results suggest that TNFalpha and IL1beta should be targeted for myositis treatment.

Anatomic localization of immature and mature dendritic cell subsets in dermatomyositis and polymyositis: Interaction with chemokines and Th1 cytokine-producing cells

OBJECTIVE

To clarify the involvement of dendritic cells (DCs), chemokines, and proinflammatory Th1 cytokines in the pathogenesis of the chronic muscle diseases dermatomyositis (DM) and polymyositis (PM).

METHODS

We characterized by immunohistochemistry the DC subsets and their interaction with cells producing chemokines and the Th1 cytokines interleukin-17 (IL-17) and interferon-gamma (IFNgamma). Immature and mature DCs were defined by the expression of CD1a and DC-LAMP/CD83, respectively.

RESULTS

Immature DCs were mainly detected in lymphocytic infiltrates in DM and PM muscle tissue samples. Mature DCs were detected in perivascular infiltrates and surrounded muscle fibers. IL-17-positive and IFNgamma-positive cells were also observed in perivascular infiltrates in both cases. We then focused on the expression of the CCL20/CCR6 chemokine/receptor complex, which controls immature DC migration, and on the expression of the CCL19/CCR7 and CCL21/CCR7 chemokine/receptor complexes, which control mature DC migration. CCL20 and CCR6 colocalized in lymphocytic infiltrates in DM and PM samples. CCL21 was rarely observed in DM samples and never observed in PM samples. CCL19- and CCR7-expressing cells were absent in both tissues.

CONCLUSION

The close association between CCL20/CCR6 and immature DCs suggests the contribution of CCL20 to CCR6+ immature DC homing. Detection of mature DCs in DM and PM muscle tissue samples despite the lack of CCL19 and CCR7 is evidence for a local maturation of DCs in inflammatory muscle tissue without lymphoid organ organization.

Interleukin-17 increases the effects of IL-1 beta on muscle cells: arguments for the role of T cells in the pathogenesis of myositis

We studied the production of interleukin (IL)-6 and CCL20/macrophage inflammatory protein-3 alpha (MIP-3 alpha) by human myoblasts and muscle samples in response to IL-17 alone or in combination with IL-1 beta. Both IL-17 and IL-1 beta induced IL-6 production by normal myoblasts and muscle samples. IL-17 had no effect on CCL20 production by myoblasts. Combination of IL-17 and IL-1 beta further increased IL-6 and CCL20 production by muscle samples but not that of CK. IL-17 induced also HLA class I, C-Fos, nuclear factor kappa B (NF-kappa B) and C-Jun expression by myoblasts but not that of HLA class II, CD40, vascular cell adhesion molecule 1 (VCAM-1) and intercellular adhesion molecule 1 (ICAM-1). Finally, immunostaining of dermatomyositis (DM) and polymyositis (PM) muscle biopsies showed IL-17 and CCL20 expression. Our study shows that low levels of cytokines produced by T cells (IL-17) and monocytes (IL-1 beta) can act in combination on skeletal myoblasts and muscle tissue.

Lack of evidence for a direct involvement of muscle infection by parvovirus B19 in the pathogenesis of inflammatory myopathies: a follow-up study

OBJECTIVE

To clarify the association between parvovirus B19 and myositis.

METHODS

Biopsy samples of muscle from eight patients with inflammatory myopathies were studied for the presence of B19 DNA by polymerase chain reaction. Expression of VP1 and VP2 capsid proteins was evaluated by immunohistochemistry. Interleukin 6 (IL-6) production was measured in the supernatant of myoblasts following incubation with parvovirus B19.

RESULTS

In seven samples, detection of B19 DNA was negative. The expression of VP1 and VP2 capsid proteins was not observed by immunohistochemistry. In one patient, detection was transiently positive but became negative despite a flare-up of muscle disease. In vitro, parvovirus B19 was not able to induce IL-6 production by myoblasts.

CONCLUSION

Our results do not support the direct implication of parvovirus B19 in the pathogenesis of myositis.

Addition of interleukin 1 (IL1) and IL17 soluble receptors to a tumour necrosis factor alpha soluble receptor more effectively reduces the production of IL6 and macrophage inhibitory protein-3alpha and increases that of collagen in an in vitro model of rheumatoid synoviocyte activation

OBJECTIVES

To evaluate the usefulness of combination treatment with cytokine inhibitors.

METHODS

A simplified model was set up to evaluate the effect of tumour necrosis factor alpha (TNFalpha) soluble receptors (sTNFR) used alone and in combination with soluble interleukin 1 receptor (sIL1R) and sIL17R on the production of markers of inflammation (IL6), of migration of dendritic cells (macrophage inhibitory protein-3alpha (MIP-3alpha)), and of matrix synthesis (C-propeptide of type 1 collagen (P1CP)). Synoviocytes were stimulated with supernatants of activated peripheral blood mononuclear cells (PBMC) from patients with rheumatoid arthritis (RA). Soluble receptors (sR) were preincubated at 1 gammag/ml alone or in combination with the supernatants before addition to RA synoviocytes. IL6, MIP-3alpha, and P1CP production was measured by enzyme linked immunosorbent assay (ELISA) in 48 hour synoviocyte supernatants.

RESULTS

IL6 production decreased by 16% with sTNFR alone compared with no sTNFR (p<0.001) and by 41% with the combination of the three sR (p<0.001). MIP-3alpha production decreased by 77% with sTNFR alone compared with no sTNFR (p<0.001) and by 98% with the combination of the three sR (p<0.001). In the presence of sTNFR alone, P1CP production increased by 25% compared with no sR (p<0.01). The combination of the three sR increased P1CP production by 48% (p<0.01).

CONCLUSION

The effect of sTNFR on IL6, MIP-3alpha, and P1CP production by RA synoviocytes stimulated by activated PBMC supernatants was further enhanced when combined with sIL1R and sIL17R.

Renal type AA amyloidosis associated with rheumatoid arthritis: a cohort study showing improved survival on treatment with pulse cyclophosphamide

OBJECTIVE

To determine the incidence of renal AA amyloidosis and its association with rheumatoid arthritis (RA) in a cohort of all renal biopsies at one referral hospital and to measure the effect of a monthly pulse of cyclophosphamide on renal function and survival in these RA patients.

METHOD

All renal biopsies with proven AA amyloidosis from a single pathology unit linked to a major nephrology referral unit in a university hospital were selected retrospectively and RA patients were identified. We studied 6931 renal biopsies. The effect of treatment with and without pulse cyclophosphamide on renal function and survival was studied in these patients.

RESULTS

From March 1977 to February 1999, the incidence of AA amyloidosis was 2.4 cases/yr. The incidence and prevalence of the association of AA amyloidosis with RA were 0.68 cases/yr and 0.22% (15/6931) respectively. RA patients treated with cyclophosphamide (n=6) had a lower rate of renal function loss (P=0.013) and a higher median survival (P=0.026) than untreated patients (n=9). During the follow-up period, two out of six treated patients (33%) and all nine untreated patients (100%) died.

CONCLUSIONS

AA amyloidosis is a rare complication of RA and complicates the evaluation of treatment. This retrospective study suggests that treatment with cyclophosphamide is able to reduce the incidence of end-stage renal failure and to increase survival. Prospective studies are needed to clarify this issue.

Osteogenesis imperfecta: lifelong management is imperative and feasible

Osteogenesis imperfecta is a group of inherited diseases responsible for varying degrees of skeletal fragility. Minimal trauma is sufficient to cause fractures and bone deformities. The classification of osteogenesis imperfecta has recently been improved by the inclusion of additional clinical and histomorphometric data. The diagnosis is often readily made in infancy; some cases, however, go unrecognized until adulthood. Lifelong multidisciplinary management is imperative. Pamidronate therapy in childhood is the most extensively studied treatment and has been proved beneficial. Other bisphosphonates are being evaluated, particularly in adults. Prevention of vitamin D and calcium deficiency is essential throughout life. Pain is common and should be given adequate attention.

Dermatomyositis associated with the presence of parvovirus B19 DNA in muscle

We report a case of dermatomyositis associated with molecular evidence of parvovirus B19 DNA in two muscle biopsies collected 5 months apart. IgG- but not IgM-specific antibodies were detected in serum. None of four serum samples was positive for parvovirus B19 DNA. The two biopsies contained B19 VP1 sequences and the second one was also positive for NS1. This is the first report of viral parvovirus B19 DNA in muscle of a patient with dermatomyositis. Latent muscle infection may contribute to the clinical picture.

Hodgkin's disease and B cell lymphoproliferation in rheumatoid arthritis patients treated with methotrexate: a kinetic study of lymph node changes

We describe 2 patients with seropositive rheumatoid arthritis treated with methotrexate (MTX) who developed Hodgkin's disease (HD) and non-Hodgkin's lymphoma. Followup allowed a lymph node biopsy at 4 different time points in 1 patient and at 2 in the other. In the first patient, the steps included a long history of benign follicle hyperplasia, a polymorphic diffuse B cell lymphoproliferation, and finally HD unassociated with Epstein-Barr virus (EBV). In the second patient, a polymorphic diffuse lymphoproliferation was followed by a monomorphic large B cell lymphoproliferation associated with EBV. The cytogenetic analysis showed a monoclonal proliferation associated with the same chromosomal abnormalities found in 1 of the clones observed in the initial biopsy. These 2 cases illustrate the complexity of the role of MTX in the outbreak of such manifestations.

Bone metastases from bronchial carcinoid tumors. Two case-reports

Two case-reports of metastatic bone disease in patients with bronchial carcinoid tumors illustrate the diagnostic challenges raised by these slowly-growing malignancies of which the primary frequently escapes early identification. The first patient had the typical picture of a primary with a single bone metastasis. Unusual features in the second patient were the large number of bone metastases, involvement of distal skeletal sites, and elevation of serotonin and 5-hydroxyindoleacetic acid levels.

Vulnerability to ventricular fibrillation related to ischaemia: comparison of the acute effects of beta-blockers and calcium antagonists

A comparative evaluation of beta-blockers and calcium antagonists as protective agents against ventricular fibrillation related to myocardial ischaemia, was attempted in the pig heart in situ of anaesthetized, open-chest animals, subjected to a temporary complete occlusion of the left anterior descending coronary artery near its origin. This occlusion resulted in fibrillation occurring after a time depending on the vulnerability to the fibrillatory process. As this time to onset of fibrillation does normally not exceed a few minutes, its determination could be achieved repeatedly in the course of an experiment, in the absence and presence of drugs such as beta-blockers and calcium antagonists. When propranolol (0.05 mg/kg, i.v.) and verapamil (0.05 mg/kg, i.v.) abolished tachycardia produced by isoproterenol (0.25 micrograms/kg/min), the triggering of fibrillation was delayed in either case: in animals under atrial pacing at a rate close to the sinus rate on each determination, time to fibrillation was prolonged from about 160 to 400 sec by propranolol and from 160 to 640 sec by verapamil, with a return to control values within 60 min. Under ventricular pacing at a constant high rate (180 beats/min), no change was observed in time to fibrillation after propranolol (0.025 or 0.050 mg/kg), whereas verapamil, in the same conditions and in the same doses, multiplied this time by about 4 and 6, respectively. Consequently, propranolol and verapamil are likely to protect against fibrillation immediately after i.v. injection, but the protection due to propranolol is only indirect and a consequence of bradycardia which tends to increase the polarization of the muscular fibres, whereas verapamil adds to the same influence a direct preventive action by avoiding a cellular calcium overload in these fibres, which is responsible for the depolarization and fluctuations of their membrane potential.

[Pharmacokinetics of fluorine contained in the Royale Saint-Yorre mineral water]

The pharmacokinetics of oral fluoride supplied by one half liter of Royale Saint-Yorre water, which contains 8.50 mg fluoride per liter, were studied in ten healthy volunteers. Fluoride plasma kinetics and urinary excretion of fluoride were determined over 24 hours. After ingestion of one half liter Royale Saint Yorre mineral water, mean peak serum fluoride level was 159 +/- 22 micrograms/l. Time to peak serum level was 1 h (0.9 +/- 0.21 h) and area under the curve from 0 to 24 hours was 1,040 +/- 168 micrograms/l/h. Mean urinary fluoride was 2.57 +/- 0.4 mg (range 1.90 to 3.32 micrograms). The authors compared their findings with previously published data on fluoride pharmacokinetics after oral administration of an enteric-coated sodium fluoride tablet containing 11.35 mg elemental fluoride (12 healthy volunteers). Both peak serum level standardized for the dose of elemental fluoride and time to peak serum level were greater with the water than with the tablet. The authors cannot conclude as to which of the two types of fluoride exhibits the best bioavailability because their absorption coefficients have not been determined. This study demonstrates that Royale Saint Yorre mineral water is a valuable source of fluoride. Additional prospective studies are needed to determine whether it has therapeutic potential.

Attenuation of the ischaemia-induced fall of electrical ventricular fibrillation threshold by a calcium antagonist, diltiazem

Calcium antagonists have been reported to decrease the incidence of sudden death in postinfarction management and vulnerability to fibrillation secondary to experimental coronary occlusion. In order to confirm such beneficial results regarding ischaemic ventricular fibrillation, the threshold intensity for fibrillation electrically induced with impulses of 100 ms and 180 beats.min-1 was measured during the course of ischaemias obtained by total occlusion of the left anterior descending coronary artery near its origin in open-chest pigs. The variations of electrical fibrillation threshold with ischaemia duration (30, 60, 120, 180, 240, 360 s) were compared under control conditions and after i.v. diltiazem (0.50 mg.kg-1 plus 0.02 mg.kg-1.min-1 over 25 min). Electrical fibrillation threshold was not influenced by diltiazem before, but raised during ischaemia, particularly from the 60th s (1.7 to 4.0 mA), with delay in the triggering of fibrillation which occurs when the fibrillation threshold falls down to the pacing threshold (0.2 to 0.3 mA). In 6 pigs out of 8, fibrillation was even avoided in the longest of the ischaemic periods considered (360 s), for fibrillation threshold ceased falling before reaching the critical level. These experimental results obtained with diltiazem are consistent with the clinical effectiveness of calcium antagonists recently observed in the prevention of postinfarction sudden death, provided that myocardial contractility is not too much adversely affected. But, left ventricular dP/dtmax was not reduced by more than 6.8% in the present experiments.

[Comparative study of different classes of anti-arrhythmia agents on the vulnerability of ischemic ventricular fibrillation]

A comparative study of the various classes of antiarrhythmic drugs as agents protecting against ischaemia-induced ventricular fibrillation was undertaken in the pig in situ heart, in anaesthetized animals which were subjected to complete temporary occlusion of the left anterior descending coronary artery. This occlusion resulted in fibrillation after a time which varied in inverse ratio to vulnerability to fibrillation. However, as this time did not exceed a few minutes, time to onset of fibrillation could be repeatedly measured in the course of an experiment, in the absence or in the presence of an antiarrhythmic drug. Under ventricular pacing at a constant rate, 180 beats/min, all the class I antiarrhythmic drugs, flecainide, disopyramide and lidocaine, in clinical dose range, reduced time to fibrillation to a large extent (25 to 50%) at the maximum of their action, with gradual return to control values within less than one hour. The enhancement of vulnerability to fibrillation was accompanied by reduction in intraventricular conduction velocity and fibrillation rate. With the same ventricular pacing, no change was observed in time to fibrillation under the influence of propranolol or amiodarone. As for verapamil, it lengthened this time considerably, up to 600%. However, bradycardia produced in usual circumstances ensures a real protection against ischaemic fibrillation with propranolol and amiodarone and enhances protection directly exerted by verapamil.

Role of asynchronous activation of the ventricular fibres by an ectopic pacemaker in the accidents, especially fibrillation, caused by Ic antiarrhythmic drugs

Class Ic antiarrhythmic drugs, which are known to slow down conduction in the ventricular muscle, are likely to impair synchrony in activity of the ventricular fibres. Asynchronous activation was first investigated between an ischaemic and a normal area by the simultaneous recording in anaesthetized, open-chest pigs of two left ventricular monophasic action potentials (MAPs) under ventricular pacing at a high rate of 180 beats.min-1. Asynchronous activation was then investigated in the intact myocardium according to the distance separating the recording from the pacing electrode. Furthermore, mechanical effects of left ventricular systole were observed by recording dP/dt(max) and mean arterial blood pressure during the pacing periods. Ischaemia was produced by transient complete occlusion of the left anterior descending coronary artery near its origin; as a result, activation time reached 85 ms in the ischaemic area under flecainide administered iv in a 2.5 mg.kg-1 dose instead of approximately 60 ms in the normal area for fibres equi-distant from the pacing electrode. Similar delays in activation were observed in the intact myocardium, depending on whether the explored region was close to or far from the pacing electrode. In the latter case, the difference in activation time may become markedly greater if the distance or the dose of flecainide are increased. This difference, which possibly exceeds one-third of the MAP duration (practically unchanged by flecainide), may account for the occurrence of fibrillation or the sudden loss of systole mechanical efficacy.