Nathalie Bautin

The Borg dyspnoea score: a relevant clinical marker of inspiratory muscle weakness in amyotrophic lateral sclerosis

The aim of the study was to determine whether the Borg dyspnoea scale could be a useful and simple marker to predict respiratory muscle weakness in amyotrophic lateral sclerosis (ALS). From April 1997 to 2001, respiratory function was perfomed in 72 patients together with the Borg score in both the upright (uBorg) and supine (sBorg) positions. Mean upright vital capacity (VC) was 81±24% predicted, sniff nasal inspiratory pressure (SNIP) was 55±26% pred, maximal inspiratory pressure (PI,max) was 57±26% pred and arterial carbon dioxide tension (Pa,CO2) was 41±6 mmHg. The mean Borg scores in the upright and supine positions were 1.7±1.5 and 2.2±2, respectively. A significant relationship between SNIP and uBorg (r = 0.4; p = 0.0007) and SNIP and sBorg (r = 0.58; p<0.0001) was observed. Upright VC, ΔVC (measured as the supine fall in VC as a percentage of seated VC), PI,max and Pa,CO2 were significantly correlated with SNIP. A cut-off value of 3 on the sBorg scale provided the best sensitivity (80%) and specificity (78%) (area under the curve 0.8) to predict a SNIP ≤40 cmH2O, indicating severe inspiratory muscle weakness. Patients with a sBorg score ≥3 also exhibited significantly lower VC, PI,max and twitch mouth pressure during cervical magnetic stimulation, and slightly higher Pa,CO2 (43.7±7 versus 39.2±5 mmHg; p = 0.05). The Borg dyspnoea scale is a valuable noninvasive test for the prediction of inspiratory muscle weakness in ALS patients.

Severe Toxoplasmosis in Immunocompetent Hosts: Be Aware of Atypical Strains

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Effects of maturation and acidosis on the chaos-like complexity of the neural respiratory output in the isolated brainstem of the tadpole, Rana esculenta

Human ventilation at rest exhibits mathematical chaos-like complexity that can be described as long-term unpredictability mediated (in whole or in part) by some low-dimensional nonlinear deterministic process. Although various physiological and pathological situations can affect respiratory complexity, the underlying mechanisms remain incompletely elucidated. If such chaos-like complexity is an intrinsic property of central respiratory generators, it should appear or increase when these structures mature or are stimulated. To test this hypothesis, we employed the isolated tadpole brainstem model [Rana (Pelophylax) esculenta] and recorded the neural respiratory output (buccal and lung rhythms) of pre- (n = 8) and postmetamorphic tadpoles (n = 8), at physiologic (7.8) and acidic pH (7.4). We analyzed the root mean square of the cranial nerve V or VII neurograms. Development and acidosis had no effect on buccal period. Lung frequency increased with development (P < 0.0001). It also increased with acidosis, but in postmetamorphic tadpoles only (P < 0.05). The noise-titration technique evidenced low-dimensional nonlinearities in all the postmetamorphic brainstems, at both pH. Chaos-like complexity, assessed through the noise limit, increased from pH 7.8 to pH 7.4 (P < 0.01). In contrast, linear models best fitted the ventilatory rhythm in all but one of the premetamorphic preparations at pH 7.8 (P < 0.005 vs. postmetamorphic) and in four at pH 7.4 (not significant vs. postmetamorphic). Therefore, in a lower vertebrate model, the brainstem respiratory central rhythm generator accounts for ventilatory chaos-like complexity, especially in the postmetamorphic stage and at low pH. According to the ventilatory generators homology theory, this may also be the case in mammals.

Polyarthrite rhumatoïde et mucoviscidose

INTRODUCTION: Inflammatory arthropathies are rare complications of cystic fibrosis (CF). We describe three cases of rheumatoid arthritis (RA) occurring in patients with this disease. OBSERVATIONS: Among the 100 patients under the care of the adult CF centre in Lille 3 presented with RA. This developed at the ages of 17, 44 and 19 years with a FEV1 of 53%, 42% and 94% respectively. They were 2 women and 1 man, with CFTR gene mutation delta F508 (1 homozygote and 2 heterozygotes) and positive sweat tests. They were colonised with Staphylococcus aureus, and rheumatoid factor and/or anti CCP antibodies were positive. The appearance and progression of RA were associated with exacerbations of bronchial infection and deterioration of respiratory function. In 2 patients the RA was continuously progressive despite intensive treatment involving high dose cortico-steroids, methotrexate (ineffective) followed by leflunomide (complicated by intractable respiratory infection). CONCLUSION: There is an increased incidence of RA in our patient population with CF. The new serum markers of RA including anti CCP are of diagnostic interest. The evolution of the two diseases is related and seems to be dependent on the level of infection leading to therapeutic problems.

Repetitive magnetic stimulation of the phrenic nerves for diaphragm conditioning: a normative study of feasibility and optimal settings

Electrical stimulation can enhance muscle function. We applied repetitive cervical magnetic phrenic stimulation (rCMS) to induce diaphragm contractions in 7 healthy subjects (800 ms trains; transdiaphragmatic pressure (Pdi) measurements; tolerance ratings). Each rCMS train produced a sustained diaphragm contraction. Sixty-five percent of the maximal available output at 15 Hz proved the best compromise between Pdi and discomfort with nonfatiguing contractions. rCMS appears feasible and should be investigated for diaphragm conditioning in appropriate clinical populations.

Cigarette smoke alters the ability of human dendritic cells to promote anti-Streptococcus pneumoniae Th17 response

BackgroundChronic obstructive pulmonary disease (COPD) is associated with chronic inflammation and impaired immune response to pathogens leading to bacteria-induced exacerbation of the disease. A defect in Th17 cytokines in response to Streptococcus pneumoniae, a bacteria associated with COPD exacerbations, has been recently reported. Dendritic cells (DC) are professional antigen presenting cells that drive T-cells differentiation and activation. In this study, we hypothesized that exposure to cigarette smoke, the main risk factor of COPD, might altered the pro-Th17 response to S. pneumoniae in COPD patients and human DC.MethodsPro-Th1 and -Th17 cytokine production by peripheral blood mononuclear cells (PBMC) from COPD patients was analyzed and compared to those from smokers and non-smokers healthy subjects. The effect of cigarette smoke extract (CSE) was analyzed on human monocyte-derived DC (MDDC) from controls exposed or not to S. pneumoniae. Bacteria endocytosis, maturation of MDDC and secretion of cytokines were assessed by flow cytometry and ELISA, respectively. Implication of the oxidative stress was analyzed by addition of antioxidants and mitochondria inhibitors. In parallel, MDDC were cocultured with autologous T-cells to analyze the consequence on Th1 and Th17 cytokine production.ResultsPBMC from COPD patients exhibited defective production of IL-1β, IL-6, IL-12 and IL-23 to S. pneumoniae compared to healthy subjects and smokers. CSE significantly reduced S. pneumoniae-induced MDDC maturation, secretion of pro-Th1 and -Th17 cytokines and activation of Th1 and Th17 T-cell responses. CSE exposure was also associated with sustained CXCL8 secretion, bacteria endocytosis and mitochondrial oxidative stress. Antioxidants did not reverse these effects. Inhibitors of mitochondrial electron transport chain partly reproduced inhibition of S. pneumoniae-induced MDDC maturation but had no effect on cytokine secretion and T cell activation.ConclusionsWe observed a defective pro-Th1 and -Th17 response to bacteria in COPD patients. CSE exposure was associated with an inhibition of DC capacity to activate antigen specific T-cell response, an effect that seems to be not only related to oxidative stress. These results suggest that new therapeutics boosting this response in DC may be helpful to improve treatment of COPD exacerbations.

Breathlessness despite optimal pathophysiological treatment: on the relevance of being chronic

In the May 2017 issue of the European Respiratory Journal (ERJ), Johnson et al. [1] proposed the term “chronic breathlessness syndrome” to describe the clinical situation in which “breathlessness that persists despite optimal treatment of the underlying pathophysiology and results in disability for the patient”. The term “disability” in this definition corresponds to “physical limitations and/or a variety of adverse psychosocial, spiritual or other consequences”, which very closely matches the World Health Organization definition of the word [2]. The relationship between breathlessness and disability was well captured in the foreword of a document published in 2013 by the Forum of International Respiratory Societies [3], which begins: “When we are healthy, we take our breathing for granted […]. But when our lung health is impaired, nothing else but our breathing really matters”. This has become the “catch phrase” of the French lung health foundation (“Fondation du Souffle”, www.lesouffle.org). The explicit definition of “chronic breathlessness” as proposed by Johnson et al. [1] differs very little from the implicit definition of “refractory breathlessness”, the term previously used in many studies, and which was proposed as a distinct entity by some of the authors of a previously published ERJ article [4]. Johnson et al. [1] submit that defining and naming this new syndrome will improve the visibility of a distressing and debilitating condition that is too often overlooked and neglected [5]. They postulate that this enhanced visibility will result in improved care and organisation of care, stronger research [6], and greater empowerment for patients and their caregivers. The Editorial by Başoğlu [7] published in the May 2017 issue of the ERJ throws new light on this notion of empowerment. Making a daring but fascinating parallel between untreated dyspnoea and torture, Başoğlu [7] reminds us how and why addressing dyspnoea in general (and probably “chronic breathlessness” in particular) is a fundamental issue not only from the point of view of medicine per se, but also from the point of view of human rights (on this, see also [8]). He also makes a very convincing case for the importance of empowerment in the management of dyspnoea. Still in the same issue of the ERJ, Calverley [9] comments on the new syndrome and, like us, concurs with Johnson et al. [1] about the relevance of making breathlessness a foremost concern of every clinician. Despite maximal pathophysiological treatment, persistent dyspnoea is a distinct entity, be it chronic or acute http://ow.ly/7cR530equaI

Exercise performance of patients with alveolar proteinosis

INTRODUCTION Cardiopulmonary exercise testing (CPET) is used to evaluate the severity of interstitial lung diseases, particularly when lung function is normal. The aim of this study was to analyse exercise capacity of patients with alveolar proteinosis. METHODS We studied 7 patients undergoing alveolar proteinosis (aged 38 +/- 5 years), Three patients complained of exertional dyspnoea, 2 had a reduced vital capacity and 5 had a DLCO of less than 75% predicted. CPET was performed on a bicycle ergometer using a standard incremental protocol. RESULTS CPET was symptom limited for all patients.. At peak exercise, VO2 was severely reduced (19.5 +/- 5.2 ml/kg/min, 58 +/- 9%). All patients developed hyperventilation. Ventilatory reserve was 42 +/- 11% of MMV, and dead space ratio (Vd/Vt) reached 0.29 +/- 0.05. Cardio-circulatory adaptation was normal (maximum heart rate 83 +/- 9%; VO2/heart rate 70 +/- 10%). Six patients exhibited gas exchange abnormalities at peak exercise (including 4 patients having a normal vital capacity): P(A-a)O2 56 +/- 18mm Hg; PaO2 65 +/- 18 mm Hg. CONCLUSION Patients undergoing alveolar proteinosis have severe impairment of aerobic capacity and gas exchange on exercise. CPET appears to be useful for therapeutic management.

Comportement à l’exercice des patients atteints de protéinose alvéolaire

Resume Introduction L’epreuve fonctionnelle d’exercice (EFX) est utile pour evaluer la severite des pneumopathies infiltratives, en particulier chez les patients dont l’EFR de repos est normale. L’objectif de ce travail etait d’analyser les caracteristiques de l’EFX chez les patients atteints de proteinose alveolaire. Methodes 7 patients (38 ± 9 ans) presentaient une proteinose alveolaire ; 3 presentaient une dyspnee d’effort ; 2 avaient une CV basse et la DLCO etait inferieure a 75 % chez 5 patients. L’EFX etait realisee sur bicyclette ergometrique selon le protocole habituel en rampe. Resultats L’EFX etait maximale (symptome-limitee) pour tous. Au pic, VO 2 etait tres abaisse (19,5 ± 5,2 ml/kg/min, 58 ± 9 %). Tous presentaient une hyperventilation avec une reserve ventilatoire conservee (42 ± 11 %) et un rapport Vd/Vt a 0,29 ± 0,05. L’adaptation cardio-circulatoire etait satisfaisante (FC : 83 ± 9 % ; VO 2 /FC : 70 ± 10 %). Six patients presentaient des anomalies majeures des echanges gazeux au pic (y compris chez 4 patients avec une CV normale) : P(A-a)O 2 : 56 ± 18 mmHg ; PaO2 : 65 ± 18 mmHg. Conclusion Les patients atteints de proteinose alveolaire presentent des alterations severes de l’aptitude aerobie et des echanges gazeux a l’exercice. L’EFX apparait comme un critere utile dans la decision therapeutique.