[Distinction between bacterial and aseptic meningitis in children: refinement of a clinical decision rule]

OBJECTIVES

To refine and to re-validate the best current tool (the Nigrovic rule: ''outpatient management may be considered for children without seizure, blood neutrophil count>or=10,000/mm(3), positive cerebrospinal fluid -CSF- Gram-staining, CSF protein>or=80 mg/dl, or CSF neutrophil count>or=1,000/mm(3)'') proposed to distinguish between aseptic meningitis (AM) and bacterial meningitis (BM) in the emergency department.

METHODS

Children hospitalized for BM between 1995 and 2004, or AM between 2000 and 2004 were included, and randomly divided into derivation (111 children, 14 BM) and internal validation (57 children, 7 BM) sets. The Nigrovic rule was refined on the derivation set, introducing new variables (purpura, toxic appearance and high serum procalcitonin), changing variables thresholds (CSF protein) and withdrawing some variables (blood neutrophil count, CSF neutrophil count), according to previous results, with the aim to obtain 100% sensitivity user friendly tool. The refined rule was then applied on the internal validation set, stayed blinded during the derivation process.

RESULTS

The refined rule was: start antibiotics in case of seizure, purpura, toxic appearance, procalcitonin>or=0.5 ng/ml, positive CSF Gram-staining, or CSF protein>or=50 mg/dl. The refined rule had 100% sensitivity on the derivation and the internal validation sets (95% confidence interval 78-100, and 65-100, respectively) with 62 and 51% specificity, respectively.

CONCLUSION

The refined rule (called Meningitest) was a highly sensitive, specific and user friendly tool that could allow to safely avoid>50% a posteriori unuseful antibiotic treatments for patients with AM.

Effects of stenting the parent artery on aneurysm filling and gene expression of various potential factors involved in healing of experimental aneurysms

SUMMARY

Intracranial stents are increasingly used in the endovascular treatment of aneurysms, but very little is known regarding their effect on the cellular and molecular evolution of aneurysms. Bilateral venous pouch lateral wall carotid aneurysms were created in 20 dogs. All dogs then underwent angiography and balloon-expandable stenting of one aneurysm four to six weeks later. Fifteen dogs underwent aneurysm harvesting at one day (n=3), four days (n=4), seven days (n=3), and 14 days (n=5) for mRNA expression analysis, using axial sections taken from the aneurysm neck and fundus for RTPCR amplification of four cytokines or growth factors: TNF-a, TGF-b1, MCP-1, and PDGFBB; two adhesion molecules: VCAM-1 and PECAM-1; five matrix modifying agents; MMP- 2, 9, TIMPs 1, 3, 4, and two cellular markers: CD34 and a-SMA. Five other dogs, sacrificed at 12 weeks, were examined for extent of filling of the aneurysm neck with organized tissue and for neointima formation at the aneurysm ostium. Angiography was performed prior to sacrifice in all animals, and compared with initial studies. Eleven out of 20 stented aneurysms showed a favorable angiographic evolution, while none of the 20 nonstented aneurysms improved (p=0.001). Pathology showed partially occluded aneurysms, with neointima formation around the stent struts.Observed trends in mRNA expression, that stenting increased expression of genes involved in organization and neointima formation, agreed with experimental hypotheses, but differences between stented and non-stented aneurysms did not reach statistical significance. Parent vessel stenting was associated with angiographic improvement of aneurysm appearance. Modifications in mRNA expression patterns following stenting deserve further study to better establish potential molecular targets to promote aneurysm healing.

Tuberculose de l'enfant après contage familial : une expérience en pédiatrie générale

The heterogeneity of clinical presentations of children in contact with a tuberculous adult do not allow simple guidelines for treatment and exams. Indications of thoracic computed tomography (CT) in young children and the risk of a follow-up without antituberculous treatment are always discussed.

PATIENTS

Sixty-nine children, belonging to 50 families, living in close contact with an adult treated for tuberculosis were explored during 7 years in a General Pediatric Unit. A CT was performed in 51 patients.

RESULTS

Mantoux test was negative in 3/17 children with typical tuberculous disease on X-ray. When results of CT were compared with those of standard thoracic X-ray, a difference for the diagnosis of mediastinal adenopathies was found only in children younger than 5 years. Fifty-eight patients were given usual treatment of latent or patent tuberculosis if indicated, or a chemoprophylaxis. All of them had normal clinical and X-ray exam 2 to 4 years later. Eleven children, initially checked in an other unit, were given no treatment, but a follow-up was set up. However, after 6 to 24 months, 4/11 had a patent tuberculosis and 5/11 a latent tuberculosis, 6/9 being aged more than 3 years.

CONCLUSION

This study shows that risk of tuberculosis after familial contamination is high, and that the choice of absence of treatment with following re-evaluation, is sometimes questionable because families or doctors do not perform the prescribed follow-up. To perform systematically a thoracic CT, searching for mediastinal adenopathies, is useful only before the age of 5 years.

[Pseudomonas aeruginosa and hospital-acquired infections]

Pseudomonas aeruginosa is involved in 10% of hospital-acquired infections as well in adults as in children. The origin of the colonization is as well endogenous as exogenous favoured by the water environment or the hand carriage. The adequate use of antibiotics is the main way to prevent hospital-acquired infections due to P. aeruginosa. Indeed, the use of fluoroquinolones is the main risk factor to select multiresistant P. aeruginosa.

Clinical decision rules to distinguish between bacterial and aseptic meningitis

BACKGROUND

Clinical decision rules have been derived to distinguish between bacterial and aseptic meningitis in the emergency room to avoid unnecessary antibiotic treatments and hospitalisations.

AIMS

To evaluate the reproducibility and to compare the diagnostic performance of five clinical decision rules.

METHODS

All children hospitalised for bacterial meningitis between 1995 and 2004 or aseptic meningitis between 2000 and 2004 have been included in a retrospective cohort study. Sensitivity and specificity were calculated by applying each rule to the patients. The best rule was a priori defined as the one yielding 100% sensitivity for bacterial meningitis, the highest specificity, and the greatest simplicity for a bedside application.

RESULTS

Among the 166 patients included, 20 had bacterial meningitis and 146 had aseptic meningitis. Although three rules achieved 100% sensitivity (95% CI 84-100), one had a significantly lower specificity (13%, 95% CI 8-19) than those of the other two rules (57%, 95% CI 48-65; and 66%, 95% CI 57-73), which were not statistically different. The ease of manual computation of the rule developed by Nigrovic et al (a simple list of five items: seizure, blood neutrophil count, cerebrospinal fluid (CSF) Gram stain, CSF protein, CSF neutrophil count) was higher than the one developed by Bonsu and Harper.

CONCLUSION

On our population, the rule derived by Nigrovic et al had the best balance between accuracy and simplicity of manual computation and could help to avoid two thirds of unnecessary antibiotic treatments and hospitalisations.

Endovascular Treatment with Platinum Coils. Recanalization is Associated with Early Increased von Willebrand Factor mRNA

SUMMARY

Recanalization after coil occlusion is a concern for long-term results of endovascular treatment. Knowledge of molecular events following coil occlusion and recanalization could help design specific strategies to promote permanent occlusion. Platinum coils were implanted into canine maxillary, vertebral or lingual arteries. Coil occlusion (treatment 1), routinely followed by recanalization was compared with two strategies to prevent recanalization: beta radiation using (32)P coils (treatment 2) and endothelial denudation, using an endovascular device, followed by coil occlusion (treatment 3). The evolution of initial complete occlusions was followed by angiography and pathology at three months. Levels of messenger RNA of vWF (von Willebrand factor), SMA (smooth muscle actin), CD14, CD31 (or PECAM-1: Platelet Endothelial Cell Adhesion Molecule-1), PDGFBB (platelet-derived growth factor), TGF-b1 (transforming growth factor), MCP-1 (macrophage chemoattractant protein), Angiopoietins, Metalloproteinases-9, 14 and inhibitors (TIMP- 2, 4) were followed by Reverse Transcription and Polymerase Chain Reaction (RT-PCR). Analyses were performed one, four, seven and 14 days after coiling, and levels of expression after the three treatments were compared using ANOVAs. Intact arteries treated with platinum coils routinely recanalize (100%), but arteries treated by denudation and coiling or with radioactive coils recanalize in only 17% and 4% respectively (P<.001). Recanalization was associated with increased levels of vWF mRNA at seven days, a finding that was not observed with denudation or radiation (P=.015). There was no other significant difference. Recanalization is associated with early vWF expression, perhaps reflecting the development of endothelialized channels through thrombus formed after coil occlusion.

Cancer chemotherapy administered via hemodialysis fistulas

End-stage renal failure (ESRF) patients can develop cancer before or after kidney disease occurs. Cancer chemotherapy often needs to be administered via the sort of central venous catheter that is normally avoided in ESRF care. Three cases are presented in which ESRF patients received chemotherapy for cancer via existing hemodialysis fistulas, and the consequences of central venous access in a fourth patient are discussed.

Prevalence of Barrett's esophagus in systemic sclerosis

OBJECTIVE

The esophagus is the most commonly affected gastrointestinal area in systemic sclerosis (SSc). Patients with SSc frequently develop gastroesophageal reflux, esophageal injury, and sometimes, intestinal metaplasia, or Barrett's esophagus (BE), which may increase the risk of esophageal adenocarcinoma. This study sought to determine the prevalence of BE and esophageal adenocarcinoma in a cohort of SSc patients.

METHODS

One hundred ten SSc patients who were receiving long-term treatment with proton-pump inhibitors (PPIs) were assessed systematically by esophageal manometry and endoscopy. Esophageal biopsies were performed when macroscopic abnormalities were detected, and BE was diagnosed histologically.

RESULTS

Among the 110 patients, 14 had BE (12.7%). None of the patients with BE had adenocarcinoma, but 3 of the 14 patients (21%) had dysplasia on esophageal biopsy. Similar proportions of patients with and without BE had abnormal peristalsis and decreased lower esophageal sphincter pressure. No association between BE and other disease characteristics was demonstrated.

CONCLUSION

In this study, 12.7% of SSc patients who had been treated with PPIs for long periods had BE, similar to the prevalence in patients with gastroesophageal reflux disease. Although none of the patients had esophageal adenocarcinoma, patients with BE should be followed up closely, particularly patients with dysplasic BE. Long-term prospective studies are warranted to determine the phenotype of SSc patients at high risk of developing dysplasia or esophageal adenocarcinoma.

Embolization as one modality in a combined strategy for the management of cerebral arteriovenous malformations

SUMMARY

We attempted to assess clinical results of management of cerebral arteriovenous malformation using a combination of endovascular, surgical and radiotherapeutic approaches. We retrospectively reviewed the angiographic and clinical data on prospectively collected consecutive patients treated by embolization from 1994 to 2004. The general philosophy was to attempt treatment by a combination of approaches only when an angiographic cure was likely or at least possible. The clinical outcome was assessed according to the modified Rankin scale. Although 404 patients were collected, complete files and follow-ups are available for 227 or 56% only. Most patients presented with hemorrhages (53%) or seizures (23%). The final management consisted in embolization alone in 34%, embolization followed by surgery in 47%, embolization and radiotherapy in 16%, and embolization, surgery and radiotherapy in 3% of patients. The embolization procedure itself could lead to an angiographic cure in only 16% of patients. When the management strategy could be completed, the cure rate increased to 66%. Complications of embolization occurred in 22.6% of patients. Overall clinical outcome was excellent (Rankin 0) in 43%, good (Rankin 1) in 38%, fair (Rankin 2) in 10%, poor (Rankin 3-5) in 2%, and the death rate was 7%. A combined strategy initially designed to provide angiographic cures cannot be completed in a significant number of patients; the total morbidity of treatment remains significant. There is no scientific evidence that cerebral arteriovenous malformations should be treated, and no clinical trial to prove that one approach is better than the other. Various treatment protocols have been proposed on empirical grounds. Small lesions can often be eradicated, with surgery when lesions are superficial, or with radiation therapy for deeper ones. There has been little controversy regarding therapeutic indications in these patients (1). The management of larger AVMs, sometimes in more eloquent locations, is much more difficult and controversial (2-4). Endovascular approaches have initially been developed to meet this challenge (5,6). It became quickly evident that embolization alone would rarely suffice to completely cure these lesions. The philosophy behind combined approaches is founded on 2 opinions: 1) There is no proven value of partial embolization, not even "partial benefits", and treatment should aim at an angiographic cure (7) and 2) By appropriately tailoring all available tools to each situation, such a cure could be reached with minimum or reasonable risks. We have used such a combined strategy for more than a decade now. Endovascular techniques and materials have evolved, and it is perhaps possible today to reach a cure by embolization alone in a larger proportion of patients than before (8). Aggressive embolizations, aiming for an endovascular cure, even sometimes in large lesions, have recently been promoted for their power or criticized for their risks (9). But before evaluating the advantages and inconveniences of new treatments, it may be wise to review the results we could achieve with a conventional approach combining endovascular, surgical and radiotherapeutic techniques.

[Helicobacter pylori infection in children of developing countries]

A characteristic feature of Helicobacterpylori infection in developing countries is early acquisition of the bacteria during childhood. Recent study has documented the frequency of transient infection in young children in particular during the first year following eradication therapy. Children living in developing countries present several risk factors for acquisition including crowding, young age, and recurrent gastroenteritis. The risk of infection increases significantly in function of the number of infected persons in a child's family. Using molecular biology techniques based on gene sequencing, we have shown that strains in different members of the same family were identical not only between parents and children but also between siblings. The relationship between chronic diarrhoea, retarded growth, iron-deficient anaemia, and Helicobacter pylori infection in children especially from developing countries remains controversial. Gram staining of biopsy smears to detect Helicobacter pylori is an efficient diagnostic method and can be a good alternative when culture is unfeasible. Respiratory testing and detection of antigens in stools are effective and appear to be well suited to diagnosis of Helicobacter pylori infection. In developing countries Helicobacter pylori is a common infectious agent warranting further study to gain insight into clinical presentation, epidemiological features, and treatment requirements including sensitivity to antibiotics

[Mycoplasma pneumoniae, community-acquired pneumonia and asthma]

Mycoplasma pneumoniae is an intracellular pathogen, devoid of cell wall, able to invade airway epithelial cells. Infection may either remain asymptomatic or induce bronchitis and pneumonia. M. pneumoniae is the first-ranking aetiological agent of community-acquired pneumonias in children over five years of age. Clinical features are usually mild, but this should not preclude the initiation of a treatment, in order to avoid serious sequelae such as impairment of pulmonary gas exchange capacity. In children at high-risk of asthma, infection with M. pneumoniae can induce exacerbation. A survey was performed in children admitted to hospital Saint-Vincent-de-Paul (Paris) for an episode of severe asthma exacerbation with persistent hypoxemia. Mycoplasma infection was identified in 26% of children with a history of asthma and 50% of those for whom the exacerbation was the presenting manifestation of the disease. Furthermore, if the Mycoplasma infection was atypical, asthma exacerbation recurred within one month. M. pneumoniae should be considered not only as a preeminent agent of respiratory infection in children, but also as a triggering factor in exacerbation and even inception of asthma. As a consequence, it is mandatory to carefully search for and actively treat Mycoplasma infection in children.

Immunocytochemical and pharmacological characterization of metabotropic glutamate receptors of the vestibular end organs in the frog

Using immunocytochemistry and multiunit recording of afferent activity of the whole vestibular nerve, we investigated the role of metabotropic glutamate receptors (mGluR) in the afferent neurotransmission in the frog semicircular canals (SCC). Group I (mGluR1alpha) and group II (mGluR2/3) mGluR immunoreactivities were distributed to the vestibular ganglion neurons, and this can be attributed to a postsynaptic locus of metabotropic regulation of rapid excitatory transmission. The effects of group I/II mGluR agonist (1S,3R)-1-aminocyclopentane-trans-1,3-dicarboxylic acid (ACPD) and antagonist (R,S)-alpha-methyl-4-carboxyphenylglycine (MCPG) on resting and chemically induced afferent activity were studied. ACPD (10-100 microM) enhanced the resting discharge frequency. MCPG (5-100 microM) led to a concentration-dependent decrease of both resting activity and ACPD-induced responses. If the discharge frequency had previously been restored by L-glutamate (L-Glu) in high-Mg2+ solution, ACPD elicited a transient increase in the firing rate in the afferent nerve suggesting that ACPD acts on postsynaptic receptors. The L-Glu agonists, alpha-amino-3-hydroxy-5-methylisoxazole-4-propionate (AMPA) and N-methyl-D-aspartate (NMDA), were tested during application of ACPD. AMPA- and NMDA-induced responses were higher in the presence than absence of ACPD, implicating mGluR in the modulation of ionotropic glutamate receptors. These results indicate that activation of mGluR potentiates AMPA and NMDA responses through a postsynaptic interaction. We conclude that ACPD may exert modulating postsynaptic effects on vestibular afferents and that this process is activity-dependent.

[Chlamydiae infections: diagnostic procedures]

The objective of this review is to critically describe the diagnostic procedures for Chlamydiae infections. Direct identification in culture remains fastidious and lacks sensitivity. Antigen detection techniques include direct immunofluorescence using monoclonal antibodies and immunohistochemistry. Until recently, serologic testing was commonly used for the diagnosis, but sensitivity was low for acute infections. The situation has been greatly improved by the advent of molecular techniques allowing direct identification of chlamydial DNA. The polymerase chain reaction has high specificity and sensitivity. Several commercially available tests can be used for C. trachomatis. For C. pneumoniae, routine tests for gene amplification are still lacking. The diagnosis is based on the combination of direct identification and search for a rise in antibody titer by serologic testing.

Le trachome : Une infection pédiatrique toujours d'actualité

Trachoma is a chronic granular conjunctivitis due to Chlamydia trachomatis serotypes A to C. The primary infection arises in the childhood while vision threatening complications occur in the adulthood. Vision decrease is mostly related to the opacification of the cornea which is due to the chronic friction of eyelashes on its surface (trichiasis), itself being a consequence of the conjunctival scarring secondary to relapsing infections. The trachoma rages in developing countries, not only in Africa but also and especially in Southeast Asia and in the region of the western Pacific. Even if the number of cases of trachoma in the world is now 6-fold lower than twenty years ago, still 83 millions of patients are affected by active trachoma, leading to the estimation that 490 millions of people should be treated in a curative or a preventive way. The fight against trachoma is based on the S.A.F.E. strategy, an acronym for surgery of trichiasis, antibiotics for patients and contact subjects, facial hygiene and environmental improvement. Concerning antibiotics, oral azithromycin is now considered as the gold standard for mass distribution against trachoma, but costs remain a major problem in developing countries. However, application of the four large-scale measures of the S.A.F.E. strategy should allow ending in the purpose fixed by the WHO organization, namely the Global Elimination of Trachoma by the year 2020.

Acquisition nosocomiale de bactéries multirésistantes dans un service de néonatologie : étude prospective et analyse des facteurs de risque

A systematic analysis of weekly nasal and rectal swabs was carried out in a neonatal unit in order to detect colonization with multiresistant bacteria (MRB).

PATIENTS AND METHODS

During a 6-month period, rectal and nasal samples were taken in 187 consecutively hospitalized newborns, the day of the admission (day 0) and every week until discharge, in order to detect MRB, mainly methicillin-resistant coagulase negative staphylococci (MRCoNS), Staphylococcus aureus and multi-resistant Gram-negative bacilli.

RESULTS

Among 187 infants, 50 were already colonized at entrance and excluded from the study. In others, 49 (35%) were colonized by at least one MRB, with a total of 71 strains isolated. The most frequent was MRCoNS, especially Staphylococcus epidermidis (66.1%). Gram-negative bacilli accounted for 9.8%. Colonization began earlier with MRCoNS than with Gram-negative bacilli, 7.8 +/- 6 vs. 15.5 +/- 16 days, P=0.004, and finished earlier 22.7 +/- 15 vs. 38.5 +/- 16 days, P=0.03. Colonized children exhibited by univariate analysis a lower birth weight, more frequent parenteral nutrition or previous hospitalization in a neonatal unit and a younger age at admission. Odds ratio for colonization were 4.06 for prematurity and 43.83 for a previous hospitalization. MRCoNS at days 15 (P <0.05) and 22 (P <0.05) were correlated with the empiric use of antibiotics. No nosocomial infection occurred during the study.

CONCLUSION

A high rate of newborns were colonized with MRB in our unit, especially MRCoNS, acquired earlier than Gram-negative bacilli, with a favoring action of empiric antibiotherapy.

New Devices Designed to Improve the Long-Term Results of Endovascular Treatment of Intracranial Aneurysms. A Proposition for a Randomized Clinical Trial to Assess their Safety and Efficacy

SUMMARY

Endovascular coiling can improve the outcome of patients with ruptured intracranial aneurysms, but angiographic recurrences are frequent compared to surgical clipping. New coils or devices have been introduced to improve long-term results of endovascular treatment but none have been the object of a valid clinical trial. We have proposed a multicentric randomized double-blind study comparing radioactive and standard coil occlusion of aneurysms. The purpose of this article is to review issues that are specific to the design of clinical trials to assess embolic agents that could improve the long-term efficacy of endovascular treatment of intracranial aneurysms. The proposed trial is a randomized, multi-center, prospective, controlled trial comparing the new generation coils to standard platinum coils. Blinding, if at all possible, is preferable to minimize bias, at least for follow-up angiographic studies that should cover a period of 18 months. All patients with an intracranial aneurysm eligible for endovascular treatment would be proposed to participate. The study would enrol approximately 500 patients equally divided between the two groups, recruited within two years, to demonstrate a decrease in the recurrence rate, the primary outcome measure, from 20% to 10%. Secondary outcome measures should assure that complications, initial clinical and angiographic results remain unchanged. Independent data safety and monitoring committees are crucial to the credibility of trials and to ensure scientific rigor and objectivity. The scientific demonstration of an improved long-term efficacy, without significant compromise regarding safety, is mandatory before considering the widespread use of a new embolic device for the endovascular treatment of aneurysms.

A randomized trial on the safety and efficacy of endovascular treatment of unruptured intracranial aneurysms is feasible

SUMMARY

The safety and efficacy of endovascular treatment of unruptured intracranial aneurysms remain undetermined. A randomized trial may be the best way to demonstrate the potential benefits of endovascular management. We propose a randomized, prospective, controlled trial comparing the incidence of subarachnoid haemorrage of patients treated by endovascular coiling as compared to conservative management. We would also study a composite outcome combining SAH and the morbidity of treatment. All patients with one or more unruptured aneurysm >> 3 mm eligible for endovascular treatment would be proposed to participate. The study would be conducted in 40-50 centres. The entire study would enrol 1800 patients, recruited over three years and followed for five years, but would be preceded by a feasibility study on 200 patients. A randomized trial comparing endovascular and conservative treatment could have an important impact on the clinical management of intracranial aneurysms.

A special report: suggested procedures for international unrelated donor search from the donor registries and quality assurance working groups of the World Marrow Donor Association (WMDA)

This special report details the World Marrow Donor Association's recommended procedures regarding the international search for an unrelated donor for hematopoietic stem cell transplantation. The responsibilities of the national hubs, transplant center and donor registry staff are outlined for all actions associated with the preliminary search, formal search, donor confirmatory typing and final donor selection.