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J D Cavallo

Publications and source records attributed to J D Cavallo.

At least 37 records · Page 2Linked to original sources
PubMed1999

[Urinary tract infection in an urban population: etiology and antibiotic sensitivity as a function of patient history].

OBJECTIVE: The aim of this study was to explore the relationship between etiological factors, bacterial isolates and Escherichia coli susceptibility to antibiotics in ambulatory patients with urinary tract infection. PATIENTS AND METHODS: A prospective study was conducted in 13 private medical laboratories in France in March 1998. Data were collected on 658 cases involving 679 strains in ambulatory patients with urinary tract infections. Data on age, gender, catheter insertion within the 7 preceding days, and history of hospitalization, urinary infection and antibiotic treatment during the 6 preceding months were recorded. The distribution of the bacterial isolates and Eschericha coli sensitivity to ciprofloxacin, cotrimoxazole, and gentamycin were studied. RESULTS: E. coli was most frequently isolated in women, in patients with no catheter or without a history of antibiotic treatment, hospitalization or urinary infection. There was no difference in E. coli sensitivity according to sex and age in women. In patients with prior antibiotic treatment, all the tested antibiotics except gentamycin were significantly less active. In case of prior hospitalization, the E. coli isolates were more resistant to amoxicillin, quinolones, cotrimoxazole and gentamycin. The level of E. coli suceptibility rose as the delay since hospitalization or urinary infection increased. CONCLUSION: Ambulatory patients comprise a heterogeneous population requiring particular attention to correctly adapt therapeutic strategies.

Adolescent↗
PubMed1999

Bacillus thuringiensis serotype H34 isolated from human and insecticidal strains serotypes 3a3b and H14 can lead to death of immunocompetent mice after pulmonary infection.

In 1995, we isolated a strain of Bacillus thuringiensis serotype H34 from severe human tissue necrosis. This bacterium was able to induce myonecrosis in immunosuppressed mice after cutaneous infection. Its potential pathogenicity for immunocompetent hosts was investigated in a mouse model of pulmonary infection. Mice infected intranasally by a suspension containing 10(8) spores died within 8 h in a clinical toxic-shock syndrome. In the same conditions, infection with a mutant without crystalline toxin, with the supernatant from a culture containing 10(8) bacteria ml(-1) and by the insecticidal strain serotypes 3a3b or H14 led to identical results. Lower inocula simply induced a local inflammatory reaction with bacterial persistence observed during the course of 10 days.

Animals↗
PubMed1999

[Discovery of a focus of intestinal bilharziasis in te Republic of Djibouti].

An unprecedented pocket of intestinal schistosomiasis was discovered in the Republic of Djibouti in 1997. The first cases were diagnosed in French and Djiboutian tourists who presented initial symptoms of bilharzian infection after bathing in the fresh-water basin under Hassan Gari Bira Falls, near Randa. Seventeen cases were subsequently confirmed by detection of anti-schistosome antibodies using indirect hemagglutination (IH) and indirect immunofluorescence (IIF) and/or detection of Schistosoma mansoni eggs in the stool. Further testing was performed in 35 village inhabitants, mostly children, who had been exposed by bathing in the basin. The IH reaction was positive in 28 patients (80 p. 100) including 17 (49 p. 100) with levels greater than 1/64. In 92 p. 100 of cases, IH findings were confirmed by IIF which indicated that association with hypereosinophilia was common. Schistosoma mansoni eggs were found in stools from 7 patients (19 p. 100) who generally displayed mild hypereosinophilia. Information concerning the zone of risk was distributed and control measures were undertaken as widely as possible in Djibouti and abroad.

Adolescent↗
PubMed1998

Bacillus thuringiensis subsp. konkukian (serotype H34) superinfection: case report and experimental evidence of pathogenicity in immunosuppressed mice.

We present a case of severe war wounds infected by Bacillus thuringiensis serotype H34 and describe the experimental protocol used to demonstrate its ability to infect mice after cutaneous inoculation. This case is interesting because B. thuringiensis is considered to be a contaminant in laboratories and receives inadequate attention.

Adult↗
PubMed1998

[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↗
PubMed1997

A plasmid-mediated CMY-2 beta-lactamase from an Algerian clinical isolate of Salmonella senftenberg.

Multiresistance to antibiotics including beta-lactams, e.g. cefoxitin, was transferred by conjugation to Escherichia coli strain C1a from a clinical isolate of Salmonella senftenberg recovered from stools of an Algerian child. The susceptibility pattern to beta-lactams was similar to the profile mediated by an AmpC-type beta-lactamase. By biochemical analysis, typical AmpC-type enzyme substrate and inhibition profiles were obtained. Finally, an ampC plasmid-encoded beta-lactamase gene was cloned and sequenced. Its deduced amino acid sequence confirmed its identity as a class C beta-lactamase. It showed 99.5% sequence identity with the plasmid-mediated beta-lactamase CMY-2. The differences in the amino acid sequences of the two enzymes were located in the signal peptide.

Algeria↗
PubMed1997

[Evaluation of bactericidal activity of cefpirome-aminoglycoside combination against Pseudomonas aeruginosa strains with intermediate sensitivity to cefpirome and in various phenotypes of beta-lactam resistance].

The bactericidal activity of cefpirome (CPO)-aminoglycoside (AG) combination was assessed by a kinetic time-kill method against 8 strains of Pseudomonas aeruginosa showing intermediate susceptibility to cefpirome (MICS: 8-32 mg/l). Six strains had an acquired beta-lactam resistance mechanism (moderate cephalosporinase hyperproduction, OXA-2 or PSE-1 enzyme production, non enzymatic resistance) and one strain was resistant to tobramycin (TOB). Antibiotic concentrations used for time-kill curves were 1/2, 1 and 2x MIC for cefpirome, 8 mg/l for tobramycin and 16 mg/l for amikacin (AKN). Bactericidal activity was defined as a (4 log10 reduction of the initial inoculum. At the concentrations used in this study, CPO was not bactericidal; AG were bactericidal in 3 to 24 hours. CPO-AG combination was bactericidal against all the strains with no secondary regrowth. For 7/8 strains, the combination of CPO with TOB and/or AKN was more rapidly bactericidal than the AG alone. In conclusion, despite an intermediate susceptibility against numerous strains of P. aeruginosa, the CPO-AG combination is bactericidal at concentrations achievable with standard dosing regimens in man.

Amikacin↗
PubMed1997

[Pseudomonas aeruginosa: bactericidal activity on various beta-lactam resistance phenotypes of 8 antibiotics and 7 combinations].

Bactericidal activities of 8 antibiotics (ticarcillin, piperacillin, piperacillin-tazobactam, ceftazidime, cefepime, imipenem, amikacin, ciprofloxacin) and of 7 combinations have been studied by time-killing curve technique for 16 Pseudomonas aeruginosa selected for their beta-lactams resistance phenotypes (3 wild strains, 5 penicillinases, 2 extended-spectrum beta-lactamases, 3 high level cephalosporinases and 3 non enzymatic resistance). Bactericidal activities of beta-lactams used alone were as follows: imipenem > cefepime > ceftazidime, piperacillin, piperacillin-tazobactam > ticarcillin. All the antibiotics combinations were synergistic or additive. However, only the combination of imipenem with amikacin was bactericidal for all strains. For the strains with penicillinases, piperacillin-tazobactam was not more effective than piperacillin. For the extended-spectrum beta-lactamases, we have observed a synergy with piperacillin-tazobactam and ciprofloxacin or amikacin.

Amikacin↗
PubMed1997

[Sensitivity to fosfomycin of multiresistant serotype 012 Pseudomonas aeruginosa. Multicenter study].

In a multicentric study including 214 strains of Pseudomonas aeruginosa, we observed that serotype O12 is more frequently sensitive to fosfomycine than other serotypes strains (72% vs 13.2%, p < 0.000001). Time killing experiments demonstrated that combination of ceftazidime-fosfomycine and amikacine-fosfomycine have usually bactericidal and synergistic activities and could be used for the treatment of multiresistant Pa O12 infections. However, an antagonism between beta-lactams and fosfomycin in disk diffusion needs an adequate concentration of both antibiotics in the site of infection.

Aminoglycosides↗
PubMed1997

[Serum HRP-2 antigens and imported Plasmodium falciparum malaria: comparison of ParaSight-F and ICT malaria P.f].

Serum levels of HRP-2 antigens against Plasmodium falciparum in 568 venous blood samples collected at two general hospitals were evaluated using the ParaSight-F (Becton-Dickinson) alone (568/568 samples) or in combination (156/568 samples) with the new ICT-Malaria P.f. (ICT-diagnostic). Comparison with the reference method (thin and thick blood smears assessed by two experienced parasitologists) showed that both tests were highly sensitive (93% and 96% respectively) and specific (98% and 98% respectively). The positive predictive values of the two tests were equal (96%) and the negative predicative values were close (96% and 98% respectively). Although both tests provided results within 10 minutes and required no special equipment for interpretation, the ICT-Malaria P.f. test seemed simpler and easier to use than the ParaSight-F test. The ParaSight-F test alone was used to monitor serum antigen levels after treatment in 24 patients. Antigen levels remained positive for at least three days after disappearance of circulating parasites (range: 3 to 28 days). Evaluation of serum levels of HRP-2 antigens can be useful for emergency diagnosis, especially in patients with low circulating parasite levels. The ICT-Malaria P.f. test seems especially suited for in-field use.

Animals↗
PubMed1996

[Antibiotic sensitivity of aerobic gram-negative bacilli isolated from severe infections in 1992: results of a French multicenter study. Groupe d'Etude d'Infections à bacilles à Gram Négatif (GEIGN)].

OBJECTIVES: Antibiotic susceptibility of 649 gram-negative bacilli involved in severe infections and isolated in 18 teaching hospitals from January to December 1992 was evaluated. METHODS: Minimal Inhibitory Concentrations were determined by agar dilution method for piperacillin, piperacillin+ tazobactam and imipenem, and by a microdilution method for 11 other antibiotics (amoxicillin, amoxicillin + clavulanic acid, cefotaxime, ceftazidime, aztreonam, ticarcillin, ciprofloxacin, fosfomycin, tobramycin, gentamicin, amikacin). Criteria of Comité Français de l'Antibiogramme de la Société Française de Microbiologie were followed for interpretation. Betalactamases were identified by isoelectric focusing and overproduction of cephalosporinase was defined by the resistance phenotype. The main species isolated were Escherichia coli (45%), Pseudomonas aeruginosa (14%), Klebsiella pneumoniae (7.8%), Salmonella spp. (7.5%), Enterobacter cloacae (4%) and Klebsiella oxytoca (4%). Most of the strains were isolated from blood culture (72.3%), respiratory tract (11.4%) and intraabdominal infections (8.6%). Most of the enterobacteria isolates were susceptible to imipenem, aztreonam, amikacin and ciprofloxacin (percentages of susceptibility were respectively 99.3, 98, 98.3 and 96.3); in most of cases clavulanic acid did not entirely restore sensitivity to amoxicillin of penicillinase-producing strains. Among 89 P. aeruginosa strains, 82% were susceptible to imipenem and ceftazidime, 81% to the association piperacillin + tazobactam and 51% to ticarcillin. Resistance rates are very high for Acinetobacter baumannii except for imipenem. CONCLUSION: Production of TEM-type penicillinase and over-production of the chromosomal cephalosporinase are the most widely observed mechanisms of resistance (respectively 22% and 9% of 649 strains). Prevalence of extended spectrum betalactamases was low (1%) and essentially observed for K. pneumoniae.

Anti-Bacterial Agents↗
PubMed1996

[Fever of unknown origin (FUO) in the camps of Rwandan refugees in the Goma region of in Zaire (September 1994)].

After the outbreaks of cholera, dysenteriae, meningitidis of which the rwandese refugees have been the victims in August and September 1994 in the camps of the Goma's area (Zaïre), the medical teams were confronted with a great number of fevers of unknown origin. In order to explore the possible etiologies, we have conducted a cases/controls study (n = 96). Clinically, the cases occur more frequently than controls headache (p < 0.001), splenomegaly (p = 0.02) and neutropeny (p < 0.001) Serologically, it has been constated non significantly difference between cases and controls, but prevalence of HIV-1 infections (19 and 6%) and arbovirus (23 and 10%) infections are very high. Arbovirosis could explain, partially or associated with HIV and tuberculosis, the presence of these fevers undeterminated more than malaria or typhus epidemic.

Acquired Immunodeficiency Syndrome↗
PubMed1996

[Subcutaneous Dirofilaria repens dirofilariasis].

The authors describe a case of Dirofilaria repens subcutaneous dirofilariasis, in a resident of Corsica (France). Epidemiological and morphological features are related for various species of Dirofilariasis. These data, mainly based on clinical history, are usually sufficient to exclude other forms of subcutaneous filariosis, especially tropical.

Adult↗