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Vincent Jounieaux

Publications and source records attributed to Vincent Jounieaux.

12 recordsLinked to original sources
PubMed2006

Apparent absence of Pneumocystis jirovecii in healthy subjects.

We prospectively investigated 30 healthy subjects with normal CD4+ T cell counts in blood and normal findings of spirometry and chest radiography for the presence of Pneumocystis jirovecii, by performing polymerase chain reaction on sputum specimens. Fifty patients with chronic obstructive pulmonary disease were investigated at the same time in the same manner; this group was used as controls for the diagnosis of pulmonary colonization with P. jirovecii. None of the healthy subjects had positive test results, whereas the fungus was detected in 8 patients with chronic obstructive pulmonary disease. The results suggest that in our region (Amiens, France), P. jirovecii is apparently uncommon in healthy subjects and that this population, therefore, plays a minor role in circulation of the fungus within human communities.

Adult↗
PubMed2005

Comparison of 2 maintenance doses (100 microg vs 200 microg) in Hymenoptera venom immunotherapy: influence of the maintenance dose on the immunologic response.

BACKGROUND: In Hymenoptera venom immunotherapy, the maintenance dose is usually 100 microg. However, persistent systemic reactions to sting challenges could be treated by an increase in the maintenance dose to 200 microg with success, suggesting greater efficiency. OBJECTIVE: To compare the effects of 2 monthly maintenance doses (100 microg vs 200 microg) on skin test sensitivity and venom specific IgE antibody levels. METHODS: Twenty-two patients receiving Vespula venom immunotherapy were enrolled in this retrospective study. After rush therapy, the 100-microg maintenance dose initially administered was maintained (group 1, n = 13) or was increased to 200 microg (group 2, n = 9). RESULTS: Levels of venom specific IgE antibody and skin test results measured before the onset of immunotherapy were comparable in both groups. Unlike in group 1, a maintenance dose of 200 microg resulted in significant decreases in venom specific IgE antibody levels and skin test sensitivity. CONCLUSIONS: Increasing the monthly maintenance dose to 200 microg results in a greater degree of change in venom specific IgE antibody levels and skin test sensitivity than when maintaining a 100-microg dose. Our data strengthen those of previous clinical studies showing the usefulness of a 200-microg maintenance dose in the case of clinical failure of a 100-microg dose.

Adult↗
PubMed2004

Similar genotypes of Pneumocystis jirovecii in different forms of Pneumocystis infection.

This study describes the genotyping of Pneumocystis jirovecii organisms isolated from three groups of patients that developed diverse forms of P. jirovecii infection; the patients were monitored in the same French hospital. Forty archival specimens from 13 adults with Pneumocystis pneumonia, eight adults colonized by P. jirovecii and 19 immunocompetent infants infected with the fungus contemporaneously with a bronchiolitis episode were analysed retrospectively. Genotyping was performed by analysis of sequences of the internal transcribed spacer (ITS)1 and ITS2 regions, and of the dihydropteroate synthase (DHPS) locus. At the ITS regions, a high diversity of genotypes, identical main genotypes (B(1)a(3) and B(2)a(1)) and the occurrence of mixed infections (more than one genotype) were observed in the three patient groups. At the DHPS locus, the results indicated the presence of mutants in the two adult groups, as well as in the infant group. Consequently, at these two independent genomic regions, P. jirovecii isolates from patients who developed different forms of infection and who lived in the same geographical region presented common characteristics. These results suggest that patients infected with P. jirovecii, whatever the form of infection they present, are part of a common human reservoir for P. jirovecii.

Adult↗
PubMed2004

Pneumocystis jirovecii dihydropteroate synthase genotypes in immunocompetent infants and immunosuppressed adults, Amiens, France.

To date, investigations of Pneumocystis jirovecii circulation in the human reservoir through the dihydropteroate synthase (DHPS) locus analysis have only been conducted by examining P. jirovecii isolates from immunosuppressed patients with Pneumocystis pneumonia (PCP). Our study identifies P. jirovecii genotypes at this locus in 33 immunocompetent infants colonized with P. jirovecii contemporaneously with a bronchiolitis episode and in 13 adults with PCP; both groups of patients were monitored in Amiens, France. The results have pointed out identical features of P. jirovecii DHPS genotypes in the two groups, suggesting that in these groups, transmission cycles of P. jirovecii infections are linked. If these two groups represent sentinel populations for P. jirovecii infections, our results suggest that all persons parasitized by P. jirovecii, whatever their risk factor for infection and the form of parasitism they have, act as interwoven circulation networks of P. jirovecii.

Adult↗
PubMed2003

Multilocus genotyping of Pneumocystis jirovecii in patients developing diverse forms of parasitism: implication for a wide human reservoir for the fungus.

Pneumocystis jirovecii ITS and DHPS genotypes were identified in 3 patient groups developing diverse forms of P. jirovecii infections: 13 patients with Pneumocystis pneumonia, 8 patients merely colonized by the fungus, and 19 immunocompetent infants with bronchiolitis developing mild P. jirovecii infection. Common P. jirovecii genotypes were found in the 3 patient groups, suggesting that common sources of P. jirovecii were involved in the fungus acquisition, and that transmission cycles of P. jirovecii infections in these patient groups are not independent. Parasitized patients, whatever the form of parasitism they present, may be part of a common reservoir for P. jirovecii.

Adult↗
PubMed2003

Pneumocystis jiroveci internal transcribed spacer types in patients colonized by the fungus and in patients with pneumocystosis from the same French geographic region.

Pneumocystis jiroveci (human-derived Pneumocystis) infections can display a broad spectrum of clinical presentations, of which pulmonary colonization with the fungus may represent an important part, occurring frequently in patients with various underlying diseases and presenting alternative diagnoses of acute pneumocystosis (Pneumocystis carinii pneumonia [PCP]). There are few data concerning the P. jiroveci genotypes involved in pulmonary colonization, whereas several genotypes responsible for PCP in immunocompromised patients have been described. In this study, P. jiroveci genotypes have retrospectively been investigated and compared in 6 colonized patients and in 11 patients with PCP who were in the same hospital. Seventeen archival bronchoalveolar lavage samples were genotyped at internal-transcribed spacer 1 (ITS1) and ITS2 of the nuclear rRNA operon. Fourteen different genotypes were identified, of which 1 was found only in colonized patients, 10 were found only in patients with PCP, and 3 were found in both patient populations. Mixed infections were diagnosed in 2 of the 6 colonized patients and in 6 of the 11 patients with PCP. The results show that similar genotypes can be responsible for PCP as well as pulmonary colonization. There is a high diversity of genotypes in colonized patients and in patients with PCP. Mixed infections may occur in these two patient populations. These shared features of P. jiroveci ITS genotypes in colonized patients and patients with PCP suggest that human populations infected by P. jiroveci, whatever the clinical manifestation, may play a role as a common reservoir for the fungus.

AIDS-Related Opportunistic Infections↗
PubMed2003

[Lemierre syndrome: unusual, but still possible].

Lemierre syndrome is a rare disease, which was life-threatening before the antibiotics era. We report here two cases with favorable outcome. Clinical features are stereotypic: tonsillis, cervical pain revealing deep vein thrombosis, and pulmonary septic metastasis. The most frequent causal germ on blood cultures is Fusobacterium necrophorum but other anaerobial bacteries can be found. Cervical Doppler-ultrasonography, and thoracic tomodensitometry are useful. Medical treatment is antibiotic therapy and anticoagulation.

Adult↗
PubMed2002

Effects of hypocapnic hyperventilation on the response to hypoxia in normal subjects receiving intermittent positive-pressure ventilation.

OBJECTIVE: To confirm the hypothesis that the ventilatory response to hypoxia (VRH) may be abolished by hypocapnia. METHODS: We studied four healthy subjects during intermittent positive-pressure ventilation delivered through a nasal mask (nIPPV). Delivered minute ventilation (Ed) was progressively increased to lower end-tidal carbon dioxide pressure (PETCO(2)) below the apneic threshold. Then, at different hypocapnic levels, nitrogen was added to induce falls in oxygen saturation, a hypoxic run (N(2) run). For each N(2) run, the reappearance of a diaphragmatic muscle activity and/or an increase in effective minute ventilation (E) and/or deformations in mask-pressure tracings were considered as a VRH, whereas unchanged tracings signified absence of a VRH. For the N(2) runs eliciting a VRH, the threshold response to hypoxia (TRh) was defined as the transcutaneous oxygen saturation level that corresponds to the beginning of the ventilatory changes. RESULTS: Thirty-seven N(2) runs were performed (7 N(2) runs during wakefulness and 30 N(2) runs during sleep). For severe hypocapnia (PETCO(2) of 27.1 +/- 5.2 mm Hg), no VRH was noted, whereas a VRH was observed for N(2) runs performed at significantly higher PETCO(2) levels (PETCO(2) of 34.0 +/- 2.1 mm Hg, p < 0.001). Deep oxygen desaturation (up to 64%) never elicited a VRH when the PETCO(2) level was < 29.3 mm Hg, which was considered the carbon dioxide inhibition threshold. For the 16 N(2) runs inducing a VRH, no correlations were found between PETCO(2) and TRh and between TRh and both Ed and E. CONCLUSION: During nIPPV, VRH is highly dependent on the carbon dioxide level and can be definitely abolished for severe hypocapnia.

Adult↗
PubMed2002

Effects of intermittent negative pressure ventilation on effective ventilation in normal awake subjects.

RATIONALE: Previous studies have shown that an increase in inspiratory pressure during nasal intermittent positive pressure ventilation (IPPV) does not result in increased effective minute ventilation (E) due to glottic interference. STUDY OBJECTIVES: To test the consequences of increases in negative pressure ventilation (NPV) on V(E). MATERIAL AND METHODS: Eight healthy awake subjects underwent NPV delivered by an iron lung. First, NPV was started at a respirator frequency (f) of 15 cycles per minute with an inspiratory negative pressure (INP) of - 15 cm H(2)O (F15-P15). Then, f was increased to 20 cycles per minute and INP was kept at - 15 cm H(2)O. Next, f was kept at 20 cycles per minute and INP was reduced to - 30 cm H(2)O (F20-P30). Finally, f was decreased to 15 cycles per minute and INP was kept at - 30 cm H(2)O. At each step and for each breath, effective tidal volume (VT), V(E), and end-tidal carbon dioxide pressure were measured. In three subjects, the glottis width was assessed using fiberoptic bronchoscopy. RESULTS: From spontaneous breathing to the first step of NPV (F15-P15), we observed an inhibition of the phasic inspiratory diaphragmatic electromyogram concomitant to a significant increase in V(E) (p < 0.0005). For the group as a whole, the increase in mechanical ventilation (from F15-P15 to F20-P30) resulted in significant increases in VT and V(E) leading to hypocapnia (p < 0.0005). Moreover, the glottis width did not decrease with the increase in mechanical ventilation. CONCLUSIONS: We conclude that in normal awake subjects, NPV allowed a significant increase in V(E). These results differ from those previously obtained with nasal IPPV in which the glottic width interferes with the delivered mechanical ventilation.

Adult↗