PubMed HealthSearch

Biomedical subjects

G Martet

Publications and source records attributed to G Martet.

At least 19 recordsLinked to original sources

Evaluation of the monocyte counting by the ABX Vega. Comparison with the manual method and fluoro-flow cytometry.

This study allowed evaluation and comparison of the precision (20 samples) and agreement (200 samples) of the relative and absolute values of the monocyte count using three methods: microscopic, flow cytometry and the automated ABX Vega hematology analyzer. Flow cytometry is the most precise method, even if the coefficient of variation of the automated analyzer is very similar. The coefficient of correlation between the ABX Vega and the flow cytometer is very satisfactory (r=0.8042). This study of the agreement also made it possible to confirm the difficulty that automated hematology analyzers have in differentiating between some granulocytes and monocytes and their propensity to overstimate the latter when the sample includes immature forms of granulocytes. This fact stresses the importance of the microscopic method, despite its lack of precision. The observed discrepancies did not lead to any difficulties in clinical interpretation; however, this finding should be taken into consideration, particularly in myleoproliferative syndromes and the laboratory monitoring of chemotherapy.

Flow Cytometry

[An anterior mediastinal mass].

A 50-year-old man developed a bronchogenic cyst complicated by hemorrhage. A complete radiographic chest work-up provided a reliable diagnostic approach. Bronchogenic cysts are usually asymptomatic incidental discoveries. Chest ultrasonography confirms the cystic nature of the mediastinal mass. Computed tomography scan and especially magnetic resonance imaging further support the diagnosis and are helpful for guiding surgery. Surgery is required because of the unpredictable risk of hemorrhage, infection or enlargement.

Biopsy

[Cyclophosphamide-induced interstitial pneumopathy. Course data of bronchoalveolar lavage apropos of a case and review of the literature].

A patient treated with cyclophosphamide for breast cancer developed functional and clinicoradiological signs of sub-acute diffuse interstitial pneumopathy. Bronchoalveolar lavage revealed lymphocyte alveolitis. Differential diagnoses were excluded and the course was favorable after cyclophosphamide withdrawal. The bronchoalveolar lavage results obtained initially and at follow-up and two previous lavages reported in the literature demonstrate the importance of this examination in the diagnosis of drug-induced pneumopathy.

Adult

[Neisseria meningitidis and meningitis].

Meningococcal meningitis epidemics can occur anywhere in the world. However this risk is particularly high during the dry season in the sub-Saharan zone of Africa known as the Lapeyssonnie meningitis belt. This area characterized by hyperendemicity that regularly gives rise to epidemics. Multilocus enzyme electrophoresis has made possible identification and monitoring of the progression of virulent clones of Neisseria meningitidis strains in the world. Monitoring is now possible by multilocus sequence typing and data bank on the Internet. Vaccination is a major prophylactic modality. The usefulness of plain group A plus C polysaccharide vaccines is limited because of poor effectiveness in young children who constitute the highest risk group. During epidemics, mass vaccination should be carried out as early as possible according to the state of alert defined for the area. More recent conjugate vaccines against group A and C, which are effective in young children and provide long-term protection by induction of immunologic memory, may allow routine vaccination in the future. Although clinical signs are often apparent, not all cases are diagnosed by clinical examination unless gravity is taken into account. Untreated the disease is always fatal. The only hope of survival is early institution of appropriate antimicrobial therapy (even prior to hospitalization). Several strains resistant to chloramphenicol have been reported and the number of strains with reduced sensitivity to penicillin is rising constantly. Although treatment remains feasible, the existence of resistant forms raises the need to monitor the sensitivity of meningococci using standardized of antibiograms.

Adult

[Djibouti, history of 2 epidemics of cholera: 1993-1994].

When two cholera epidemics broke out in Djibouti, respectively in 1993 and 1994, Bioforce was obliged to intervene. The first time, three goals were pursued: setting up a rehydration centre in a tent, organizing epidemiological surveillance and training local personnel in treatment and diagnosis techniques. The next year, the epidemic followed serious flooding. The epidemiological analysis showed that cholera had become endemic in the poor neighbourhoods of the town and that epidemic break-outs were favoured by contaminated surface water and disturbances in the distribution of drinking water. The epidemic of 1997, likewise following flooding, only confirmed this point of view.

Cholera

[Resistance to chloroquine and cycloguanil of Plasmodium falciparum in patients arriving in France after travel in Africa without chemoprophylaxis].

The in vitro susceptibility of chloroquine and the genomic profile of dihydrofolate reductase (DHFR) codon 108 was determined against african isolates of P. falciparum (Pf) from imported malaria cases without previous drug intake by an isotopic microtest or PCR + RFLP. Pf resistance to chloroquine or to the DHFR inhibitor was present in 49% and 46% of isolates, respectively. Pf drug resistance was more frequent in permanent than in seasonal malarial transmission areas and chloroquine plus DHFR resistance reached 28% in years 1995-97. Updating the guidelines for the prevention of malaria in travellers to Africa is necessary.

Africa

[Standardization of the Neisseria meningitidis antibiogram. Detection of strains relatively resistant to penicillin].

Studying the susceptibility of 189 Neisseria meningitidis strains to penicillin, amoxicillin, cefotaxime, ceftriaxone, chloramphenicol and rifampicin by determination of minimum inhibitory concentrations (MICs) by agar dilution (reference method), E-test and disc diffusion method on Mueller-Hinton agar at 37 degrees C with 5% CO2 enabled us to standardize the antibiograms. While MIC determination by agar dilution is still the reference method, it is possible to obtain exact or approximate MIC values using the E-test. For laboratories that cannot determine penicillin MICs, it is impossible to detect strains that are relatively resistant to penicillin (RRP strains: 0.1 < or = MIC < or = 1 mg/l) using a 10-U penicillin disc. A 1 microgram-oxacillin disc allows MIC to be determined in most cases when the oxacillin inhibition zone is < or = 10 mm. Such strains must be sent to a reference laboratory for exact MIC determination. Based on our results and literature data on pharmacokinetics, we propose critical concentrations for these various antibiotics as well as critical diameters for chloramphenicol and rifampicin discs.

Amoxicillin

Pulsed-field gel electrophoresis analysis of clonal relationships among Neisseria meningitidis A strains from different outbreaks.

Pulsed-field gel electrophoresis was used to analyze the DNA of 67 Neisseria meningitidis A strains from five African outbreaks occurring between 1988 and 1996. Endonuclease Bg/II was used to cut chromosomal DNA, generating 19 analyzable fragments. This technique allowed comparison of clonal relationships between outbreak strains and revealed that the same pulsotype was responsible for the outbreaks. This pulsotype is closely related to strain B54, subgroup III reference strain, Finland, 1975, showing only two fragment differences.

Africa

[Malaria attack: a very late relapse due to Plasmodium vivax].

Plasmodium vivax malaria late-forms rarely exceed two years--the authors reported a late-form more than twenty years after a stay in endemic area. This late-form occurred in an immunocompromised patient with two terminal-stage neoplasia receiving radio, chimio corticotherapy associated with anemia and thrombopenia. Repeated-tests allowed the diagnostic.

Adenocarcinoma

[Research on three parasitic infestations in rats captured in Marseille: evaluation of the zoonotic risk].

A cross sectional survey was carried out on a population of 82 rats (Rattus norvegicus and Rattus rattus alexandrinus) trapped in Marseille. The main histopathological finding was the presence of adults or eggs of Capillaria hepatica in 44% of the animals. 21% were found with fleas (Xenopsylla cheopis). There was no evidence of trichinosis in any of the rats examined. Hepatic capillariasis is a zoonosis seldom described in human beings. About 30 human cases have been reported in the world. Human infestation occurs first by consumption of raw rat liver containing un-embryonated eggs causing only pseudoparasitism without disease. The genuine mode of infestation is the consumption of sullied soil with rats feces containing embryonated eggs. Therefore parasites provoke, true as in rat inflammatory lesions, necrosis and fibrosis of the liver. The treatment associates antiparasitic drugs such as ivermectine, disophenol or pyrantel tartrate. The presence of a large population of infested synanthropic rats requires epidemiological monitoring and extermination of rats. All physicians must be informed of this potential risk.

Animals

[Malaria epidemic during a military-humanitarian mission in Africa].

A malaria epidemic broke out among French servicemen during a humanitarian military mission carried out in Central Africa in 1996. The purpose of this study was to determine compliance with drug prophylaxis for malaria by measuring blood levels of antimalarial drugs (combination treatment using chloroquine-proguanil or treatment with doxycycline) as well as to assess the conditions of vector control. The incidence density rate of malaria over a 60-day period was 3.1 cases per month per 100 men. Only reinforcement troops were affected. The risk of developing malaria was 5 times higher among new arrivals than in servicemen who had been in the zone for several months (95% CI relative risk = [2.9-7.8]). Type of prophylactic treatment had no effect on the incidence density rate. Study data showed that 40.2% of those treated for malaria were not in compliance with prophylactic treatment at the time of the malarial attack and that those who were in compliance with prophylaxis, i.e. the remaining 59.8%, presented a strain of plasmodium that was resistant to the prophylactic drugs at doses used. Findings also indicated the epidemic occurred mainly because operating conditions prevented implementation of proper vectorial control. The risk of epidemic could probably have been reduced by improving compliance with prophylactic treatment and changing standard vectorial control techniques, e.g. by using insecticide-treated uniforms.

Africa, Central