Neonatal pancytopenia in a child, born after maternal exposure to natalizumab throughout pregnancy.

Natalizumab is a monoclonal antibody indicated for the treatment of patients with relapsing-remitting multiple sclerosis. Its use is prohibited during pregnancy. However, natalizumab exposures throughout the gestation period or during the third trimester, because of intense disease activity, are possible and begin to be reported. There are enough reassuring arguments against a teratogenicity, through pregnancy registries; but deleterious effects in the monitoring of newborn, are not well known. A disorder of hematopoiesis is possible with anemia, thrombocytopenia or pancytopenia, as discussed by the author through an observation. These hematological disorders seem to be asymptomatic; they resolve spontaneously and require a simple biological and clinical monitoring of the newborn.

[Type 2 neurofibromatosis: intergenerational differences in genetic and clinical expression]. / Neurofibromatose de type 2 : différence inter-générationnelle d'expression génétique et clinique.

INTRODUCTION: Neurofibromatosis type 2 (NF2) is a rare dominantly inherited disease. Its clinical presentation can be completely different in children and adults and early diagnosis is often difficult. The NF2 gene molecular analysis can help for diagnosis, but its result can be negative in case of NF2 mosaicism. OBSERVATIONS: We report the case of a 43-year-old man who had developed a severe phenotype with bilateral vestibular schwannomas at 19 years of age. His son presented a retinal hamartoma with loss of vision in his right eye at 2 months of age. At 9 years of age, asymptomatic schwannomas of the cranial nerves were discovered: cranial nerves X (left), XI (left), and VIII (bilateral). Partial constitutional NF2 deletion (from exons 2-7) was detected in his son. The deletion was not detectable in the DNA blood of his father and we strongly suspect a mosaic form of NF2. CONCLUSION: Ophthalmological manifestations can be the initial sign of NF2 in childhood. These features must be actively sought during the first year of life in individuals at risk of NF2. NF2 mosaicism is often described as a mild form of NF2 with a very low risk of transmission to the carrier's children. We show that NF2 mosaicism can sometimes develop severe NF2 symptoms and we confirm that the transmission risk to the offspring depends on the proportion of zygotes carrying the mutation. NF2 remains a life-limiting and life-spoiling condition. Early diagnosis is necessary to prevent complications and the follow-up of NF2 patients must be organized throughout life in specialty centers.

[Dysautonomic syndrome of the face with Harlequin sign and syndrome: Three new cases and a review of the literature]. / Syndromes dysautonomiques du visage avec signe et syndrome d'Harlequin : étude de trois cas et revue de la littérature.

INTRODUCTION: Harlequin phenomenon is characterized by a strictly unilateral erythrosis of the face with flushing and hyperhydrosis, and controlaterally a pale anhydrotic aspect. This syndrome can occur alone or associated to other dysautonomic phenomena such as Horner syndrome, Adie syndrome or Ross syndrome. PATIENTS AND METHODS: We report three cases: two patients presented a Harlequin sign, associated with Horner syndrome for one and Ross syndrome for the second. The etiologic investigation was normal, allowing recognizing the idiopathic nature of the disorder. For the third patient, Harlequin syndrome was observed in a neoplastic context due to breast cancer, metastatic dissemination, and bone metastases involving the right side of the T2 body. DISCUSSION: We reviewed the literature: 108 cases have been described. This syndrome occurred alone in 48 patients and was associated with other dysautonomic syndromes such as Horner syndrome in 38 patients, Holmes Adie syndrome in six, and Ross syndrome in six; both Ross and Holmes Adie syndrome were associated five cases and associations were not reported in five patients. The pathophysiological mechanisms of this autonomic cranial neuropathy, the possible etiologies, and therapeutic management were discussed. CONCLUSION: Harlequin phenomenon with flushing and unilateral hyperhydrosis is rare, occurring alone or in combination with other autonomic syndromes of the face. Idiopathic in two-thirds of cases, Harlequin phenomenon does not require specific treatment; sympathectomy may be discussed in the severe cases with a significant social impact.

[Thyrotoxic hypokaliemic periodic paralysis revealing Graves' disease in a male Caucasian]. / Paralysie périodique thyréotoxique hypokaliémique révélatrice d'une maladie de Basedow chez un caucasien.

OBJECTIVES: Hypokaliemic thyrotoxic periodic paralysis (TPP) is an uncommon complication of hyperthyroidism. Mostly described among Asian patients, it is rare in other ethnic groups, in particular in Caucasian people. CASE REPORT: We present the case of a Caucasian male admitted to our unit after several paretic episodes. Tachycardia, goiter and mild proptosis led to the diagnosis of Graves' disease. CONCLUSION: Rare in the Caucasian population, TPP involves dysfunction of the NA-K-ATPase pump. Beta-blockers should be associated with medical or surgical treatment of hyperthyroidism.

[Toxic leucoencephalopathy after use of sniffed heroin, an unrecognized form of beneficial evolution]. / Leucoencéphalopathie toxique après consommation d'héroïne prisée "sniff", une forme méconnue d'évolution favorable.

INTRODUCTION: Serious leukoencephalopathy can be related to heroin injection or inhalation. OBSERVATION: We report the first case of leukoencephalopathy observed three weeks after a 46-year-old man sniffed heroin. The clinical presentation included cognitive and behaviour disorders, pyramidal irritation and slight gait instability. Blood and cerebrospinal fluid analyse were normal. Brain magnetic resonance imaging showed diffuse, symmetrical supratentorial white matter lesions producing high intense signals on FLAIR and b1000-weighted sequences. Proton spectroscopy revealed an increased rate of cholin, in favour of active demyelinated lesions. Brain biopsy showed intramyelinic oedema with reactive gliosis. After two and a half years, moderate attentional fluctuations and difficulties in initiating activities persisted. Repeated MRI showed a reduction of the leukoencephalopathy. CONCLUSION: Heroin could be a cause more common than thought of leukoencephalopathy. The clinical and radiological expression and prognosis could be related to the mode of consummation (inhalation, intravenous injection, sniffing). This parameter may modulate severity and localization of brain lesions. More systematic use of MRI for patients with psychiatric symptoms after heroin intoxications could lead to a better evaluation of heroin-related neurotoxicity and potentially improve prevention.

Antibiotic accumulation and membrane trafficking in cystic fibrosis cells.

Cystic fibrosis (CF) results from mutations in the gene encoding the CF transmembrane conductance regulator (CFTR) which is a regulated chloride channel. The deltaF508 mutation prevents the post-translational glycosylation and membrane insertion of the protein. Severe disease follows, with the formation of a viscous mucus and subsequent chronic bacterial infection of the lungs, necessitating frequent, and often long, periods of antibiotic treatment. The pharmacokinetics of antibiotics in CF patients are abnormal, with lower blood serum levels and higher clearance rates which have never been satisfactorily explained. We found that accumulation of gentamicin in nasal polyp tissue non-CF cells was subject to regulation by the effectors and inhibitors of CFTR function; regulation was lost in deltaF508 CF cells and accumulation was more than doubled because of the inhibition of exocytosis.

The mechanism of action of chlorhexidine.

Chlorhexidine did not inhibit ATPase in intact cells of Escherichia coli K12 W1317i-, even at bactericidal concentrations, and ATP hydrolysis was greatest at the highest concentration (40 mg/l), even though no net uptake of substrate occurred. Like dinitrophenol and tribrominated salicylanilide, polymyxin and chlorhexidine collapsed the membrane potential at inhibitory concentrations. Membrane disruption, and not ATPase inactivation, is considered the lethal event in chlorhexidine action.

[Plasmid analysis of antibiotic resistant Shigella isolates]. / Antibiyotiklere dirençli Shigella izolatlarinda plazmid analizi.

A correlation between the multiple drug resistance patterns and the plasmid profiles given by 70 clinical isolates of Shigella sonnei and Shigella flexneri was investigated in this study. The most common plasmids were purified from different isolates by electroelution and characterized via restriction endonuclease digestions.

Comparison of Muller-Kauffmann tetrathionate broth with Rappaport-Vassiliadis (RV) medium for the isolation of salmonellas from sewage sludge.

The Rappaport-Vassiliadis (RV, modification of Rappaport's) medium was superior to Muller-Kauffmann tetrathionate broth (MKT) for the enrichment and isolation of salmonellas from sewage sludge samples, either naturally contaminated or artificially inoculated with salmonella. Isolation rates for RV (42 degrees C) were higher even when MKT (43 degrees C) performance was improved by the use of brilliant green sul-phamandelate agar. Kinetic results show that the suppression of the competing flora was poorer in MKT than in RV. The use of high inoculum to medium volume ratios (e.g. 1:5000) increased the isolation rates from RV and kinetic data explain why this was so.

Growth kinetics of mixed culture in salmonella enrichment media.

A technique for investigating the kinetics of salmonella enrichment is reported. Its use with four enrichment media (Rappaport's medium, Muller-Kauffmann tetrathionate broth (MKT) tetrathionate broth and selenite F) is described and the effect of elevated temperature on the growth kinetics shown. Rappaport's medium at 37 degrees C and MKT at either 37 degrees C or 42 degrees C were far superior to selenite F and tetrathionate broth in their selective properties and, with the exception of Rappaport's medium, the use of elevated temperature increased the selectivity of the media.

A proposed life cycle for the Reiter treponeme.

Direct microscopical observations of single developing cysts in sealed slide microcultures prepared from 5-days-old tube cultures of the Reiter treponeme revealed two distinct phases in the life cycle. In one phase transverse fission was the main method of multiplication while in a second phase, occurring when conditions in the medium became unfavourable for propagation, cysts developed. These could release large numbers of actively motile treponemes when returned to optimum growth conditions. These observations, together with results of the dilution method for the calculation of the Most Probable Number and the absence of a response in treponemes killed by high temperature (45 degrees C) or abnormal pH (10), showed that the cysts were viable and a mode of propagation for the Reiter treponeme.

The efficiency of surgical masks of varying design and composition.

Five different types of surgical mask of varying design and composition of natural and synthetic fibres were tested for their efficiency in vivo by means of a special test chamber. Contaminated particles escaping through or around the mask during speech by the wearer could be collected and sized. Analysis of the data showed that the gross efficiency of all the masks was high, but that some masks were distinctly better at small particle 'filtration' than others. There was a significant difference in efficiency between the best and worst masks. The best masks contained more fabric, were softer and were pleated, while the worst were stiffer, smaller and not pleated. Reusable cotton fabric masks were as effective as synthetic fabric masks when made to a good design.