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M Castets

Publications and source records attributed to M Castets.

At least 19 recordsLinked to original sources

[Use of the Bactec TB 460 method for the bacteriological diagnosis of tuberculosis. Results of a multicenter study].

Isolation of Mycobacteria on Loewenstein-Jensen medium lasts many weeks. The use of Radiometric method (Bactec TB 460) reduces the delays. Results of 79,064 cultures are reported from a multicentric study associating 16 laboratories. The average was 4.8% of positivity and 2.51% of contamination. The comparison of the results with conventional method previously obtained shows that radiometric method is more sensitive and contaminations are less numerous. Concerning hemocultures the Bactec method is very usefull. Among 11,277 tests performed 907 were positive (8.04%). Mycobacterium avium was identified in 89% of the cases. Identification test utilizes Biochemical and NAP tests, but also more and more Nucleic probes. The antibiotic sensitivity is performed in five days. The mean delay of analysis is about 25 days, lessening by half the conventional method delays. Nevertheless, Bactec method has the following inconveniences: syringe inoculation, use of radiolabelled products, expensive cost.

Anti-Bacterial Agents

[Sacral tuberculous osteitis].

The authors report a case of a 5 year old child suffering from isolated sacral tuberculosis which presented as sudden and total loss of function of the left leg. The rarity of this bony site, and the recurrence at nine months of a presacral abscess after 9 months of anti-tuberculous treatment in an HIV negative child, vaccinated with BCG, justify the presentation of this observation.

Child, Preschool

Influenza epidemic among a community of elderly people in spite of vaccination.

An outbreak of influenza occurred in a nursing home of 81 vaccinated elderly people. The clinical attack rate was 73%. The responsibility of an A/H3N2 strain was proved in 12 patients and 2 staff members of the 15 investigated persons. The vaccine was effective in reducing mortality but not morbidity. An antigenic drift between the wild and the vaccine strains was involved in the inefficiency of the vaccination.

Aged

Polymerase chain reaction amplified HTLV-I, HIV-1 and HIV-2 DNA fragments in subjects with mixed retroviral infections.

Serum and peripheral blood mononuclear cells from eight patients from the Ivory Coast with positive screening test results for retroviral infections were studied by serology (ELISA, Western blot (WB), synthetic peptide test), cell co-culture, and polymerase chain reaction (PCR). Two HIV-2 infections with indeterminate interpretation on HIV-1 WB were detected, two were clear dual HIV-1/HIV-2 infections, three were ambiguous mixed HIV-1/HIV-2 infections, and one was a triple retroviral infection by HTLV-I, HIV-1 and HIV-2. Four slow/low HIV-1 strains were isolated at the expense of HTLV-I and HIV-2 strains. The ELISA tests were found to be very sensitive. Indeterminate WB interpretations were frequent (HTLV-I, four; HIV-1, three; HIV-2, two). PCR provided clear evidence of multiple retroviral infections in three cases and enabled interpretation of indeterminate WB samples in three cases. One sample presented a puzzling pattern with positive PCR results for HIV-1 and HIV-2 associated with negative or indeterminate serological results. Thus, our data emphasise the need to analyse serological as well as virological markers to gain better insight on mixed retroviral infections, especially in endemic areas such as West Africa.

Base Sequence

[Q fever and fetal death in utero. Two cases].

Some cases of late abortion occurring after a Coxiella burneti infection, more often with a chronic evolution, have already been mentioned in the literature. We reported here two cases of early abortion, contemporaneous of an acute infection due to C. burneti. Two patients, after a contact, before and at the beginning of the pregnancy, with an animal susceptible to contaminate human beings by C. burneti, presented no clinical symptom characteristic of Q fever. The fetal death for the two cases was found out at the 17th week of amenorrhoea. All the investigations in order to search for an abortion etiology remained negative. Only, the specific serologies showed an acute infection due to C. burneti.

Adult

An epidemic of respiratory syncytial virus in elderly people: clinical and serological findings.

In 1984-1985, an outbreak of respiratory syncytial virus (RSV) infection occurred in two geriatric wards. Among 68 patients (mean age +/- SD = 82.5 +/- 12.5 with respiratory signs, 52 had signs caused by RSV infection. Among all patients, the clinical and serological attack rates were 61.2% and 75.0%, respectively. The most frequent clinical presentation was intensive coughing (96.1%) and fever (96.1%) associated with expectorate (63.5%). The duration of the respiratory symptoms was 5 to 7 days. The disease gradually resolved, although in eight (15.4%) patients complications occurred. For periods of up to 1 year after infection, 172 sera were obtained and tested by complement fixation test (CFT), fluorescent assays for titrating specific IgG, IgA, and IgM, and Western blotting. Specific IgM appeared in six (11.5%) of the infected patients and peaked 2 to 6 months after infection, and there was no significant correlation with severity of clinical symptoms. However, higher peak G and A antibody responses were observed in persons with rales (CFT: P = 0.008; IgG: P = 0.042; IgA: P = 0.020), cough (IgG: P = 0.034), sputum (IgG: P = 0.030), dyspnea (CFT: P = 0.024), conjunctivitis (CFT: P = 0.025), and bronchitis (CFT: P = 0.018). The temporal patterns of IgA and CFT results were found to be similar, whereas IgG peaked later, i.e., between 2 and 6 months. The patients with the most severe symptoms had the highest antibody titers obtained by conventional tests and by Western blots. Thus, RSV can be an epidemic pathogen among elderly persons, although this illness is usually mild.

Aged

[Evaluation of ELISA using A60 antigen from Mycobacterium bovis BCG: specific IGG and IGM in mycobacterial infections].

The authors have evaluated an ELISA (A60-Tb, Anda biologicals) allowing the detection of specific IgG and IgM against A60 antigen from Mycobacterium bovis BCG during mycobacterial infections. This study included sera from 110 african subjects and from 71 French subjects distributed in 4 clinical groups: 55 tuberculous patients (I), 41 leprous patients (II), 33 pneumopathies (III) and 52 healthy subjects (IV). Serological results were compared taking as reference for the diagnosis of tuberculosis the positivity of culture and/or that of a direct examination, and for leprosy the positivity of a direct examination associated either with a Mitsuda's reaction or with an histopathological examination. IgG were found to be more discriminative than IgM. Considering together the results of groups I and II, the authors found a sensitivity of 95.8 p. cent and a specificity of 75.3 p. cent with threshold of 200 U/ml for specific IgG. Anti-A60 antigen antibodies obtained for groups I and II were significantly higher (IgG: p less than 0.0001; IgM: p less than 0.001) than those observed in other groups. African subjects presented IgG titers higher than those obtained by French subjects (p less than 0.0001). IgM response was more frequent among group II (97.6 p. cent) than group I (21.8 p. cent). However, IgG (26.9 p. cent) and IgM titers (30.8 p. cent) were detected among group IV. This test would allow a control of therapeutic efficacy with an additional interest for classifying borderline forms of leprosy.

Adult

[Resistance of Mycobacterium tuberculosis. An 8-year survey in the Poitiers area].

We have studied in Poitiers area from 1977 to 1984 the resistance of 853 Mycobacterium tuberculosis strains to the main anti-tuberculosis drugs. The overall rate of drug resistance was showed to be steady over the years while the primary resistance rate has decreased. The only one drug resistance has concerned para-aminosalicylic acid, streptomycin and isoniazid. Foreigners, most of them Asian people or North-African people, often bear resistant tubercle bacilli (29,03%) compared with French people (9,29%). We encountered drug resistance phenomena essentially among less than 60 years old patients. Drug susceptibility tests remain indispensable for a good epidemiologic supervision at the time of relapses and among patients possibly infected with multiresistant germs.

Adult

[Anti-BCG titers of healthy and tuberculous Africans. Use of the indirect immunoperoxidase test].

This study was intended to assess the presence of antibodies to BCG: immunoglobulin G (IgG) and immunoglobulin M (IgM) in three homogenous african populations: 76 tuberculous patients, 55 adult healthy subjects and 46 newborn. We have used an indirect immuno-peroxidase reaction. Tuberculous patients were clearly distinguished from the other two groups by raised IgG titres, associated with severe clinical and radiological features. In the control population, the IgG anti-BCG were also present, but to a lesser degree. The IgM anti-BCG were seen in high titres (greater than 20 in this study) in healthy adults and patients. The two populations differed significantly (p less than 0.001), nevertheless some healthy adults achieved IgM titres comparable with tuberculous patients. This simple test could be an interesting contributory factor in cases of diagnostic difficult and enables a serological assessment of patients having BCG therapy.

Adolescent