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I Gadea

Publications and source records attributed to I Gadea.

33 records · Page 2Linked to original sources

Effect of pH and buffer system on the in-vitro activity of five antifungals against yeasts.

We have compared the effect of various media on the in-vitro activity of amphotericin B, flucytosine, fluconazole, itraconazole and ketoconazole against 93 clinical yeast isolates by a micro-broth dilution technique. The media used were: RPMI 1640 with 2% glucose, buffered with 0.165 M MOPS at pH 7.0; the same medium, but buffered at pH 7.4; and the same medium, but buffered at pH 7.4 with 0.15% sodium bicarbonate. The three media gave similar results with azole antifungals and flucytosine, but the medium buffered at pH 7.0 failed to detect different populations of yeasts with respect to amphotericin B susceptibility. In the case of the media buffered at pH 7.4, Candida krusei was significantly less susceptible to amphotericin B than Candida albicans or Torulopsis glabrata. We could not evaluate the results obtained with Candida parapsilosis and Cryptococcus neoformans since these species did not grow adequately in all three media.

Amphotericin B↗

[Induction of interleukin-6 by Borrelia burgdorferi in different cell cultures].

BACKGROUND: To determine variability, if exists, in interleukin-6 (IL-6) response by different cell cultures stimulated by Borrelia burgdorferi. METHODS: Five human embryonic diploid fibroblast cell lines (three of them of lung origin) and four human synovial cell cultures were used. Induction of IL-6 was made with B. burgdorferi B31 culture and E. coli lipopolysaccharide (LPS). IL-6 was determined by a commercial EIA (Coaliza IL-6). RESULTS: All cell cultures produced IL-6 under basal conditions and responded after adding E. coli LPS. The IL-6 production after B. burgdorferi stimulation was higher than that induced by LPS with three out the four synovial cell cultures and lowest with lung fibroblasts. CONCLUSIONS: The ability of B. burgdorferi to stimulate IL-6 production depends on the nature and origin of cell cultures. This variability and the fact that the most reactive cell cultures were those of synovial precedence may correlated with some clinical aspects of the Lyme disease.

Borrelia burgdorferi Group↗

[Spontaneous meningitis caused by gram-negative bacilli].

OBJECTIVE: To analyze the causative factors, clinical and microbiological characteristics, and prognosis in spontaneous meningitis caused by Gram-negative rods in adult patients. METHODS: Descriptive and retrospective study of all clinical records and microbiological findings in patients diagnosed of meningitis by Gram-negative bacilli, from 1973 to 1995, at Fundación Jiménez Díaz. RESULTS: Twenty patients had spontaneous meningitis caused by Gram-negative bacilli (2.1% of all diagnosed meningitis during this period). Fourteen patients were older than 65 years (range: 36-81; p < 0.05). Ninety-five percent of cases had an extranosocomial origin (p < 0.001). Ninety percent of patients had some underlying disease (p < 0.001). Twelve patients were immunosuppressed. Seven patients had changes in the urinary tract or repeated UTI infections. The most common clinical symptoms were a decrease in consciousness level, fever, and neck stiffness. Cerebrospinal fluid (CSF) in 18 patients showed cellular and biochemical changes. The CSF smear revealed the presence of Gram-negative bacilli in 15 patients. E. coli was the microorganism recovered most frequently. Immunosuppression (p < 0.05), septic shock (p < 0.001) and antimicrobial therapy not including a third generation cephalosporin (p < 0.01) were independently associated with mortality. CONCLUSIONS: Spontaneous meningitis by Gram-negative bacilli is an uncommon infection. It occurs mainly in immunosuppressed patients older than 65 years or with changes in the urinary tract. It usually has an extranosocomial origin. The investigation of CSF is a highly effective for diagnosis. Therapy with third generation cephalosporins has notably improved its prognosis.

Adult↗

Correlation of pharmacodynamic parameters of five beta-lactam antibiotics with therapeutic efficacies in an animal model.

The MIC is the main microbiologic parameter used to predict the efficacies of antibiotics. However, it is well known that MICs may vary according to the inoculum size used (inoculum effect), especially with some beta-lactam antibiotics. In order to correlate the pharmacologic and microbiologic properties of some beta-lactams, an experimental model of intraperitoneal infection caused by Escherichia coli in nonneutropenic and neutro-penic mice was developed. The animals were treated with three different doses of either ampicillin, piperacillin, aztreonam, cefazolin, or cefotaxime. The linear regression analysis obtained in our model shows a better correlation between in vitro activity and efficacy when the MICs considered were those obtained with a large inoculum (ca. 1 x 10(8) CFU/ml) instead of the standard inoculum (5 x 10(5) CFU/ml). The correlations for the MICs obtained with the large inoculum were 0.78 for log2 maximum concentration of drug in serum (Cmax)/ MIC, 0.72 the time that the concentrations exceeded the MIC, and 0.79 for log2 area under the serum concentration-time curve (AUC)/MIC at 24 h in nonneutropenic mice. The corresponding values in neutropenic mice, also for the MICs obtained with the large inoculum, were 0.54, 0.68, and 0.64, respectively, at 24 h. A good correlation was also obtained for the same parameters in nonneutropenic mice at 48 h. The values of Cmax, AUC, and the time that the concentrations exceeded the MIC were parallel among the antibiotics studied, and our study confirms that the time that the levels in serum exceed the MIC is a significant parameter determining the efficacies of beta-lactam antibiotics, but the correlation is much better when the MICs obtained with the large inoculum instead of those obtained with the standard (low) inoculum are considered.

Ampicillin↗

Bronchoalveolar lavage for the diagnosis of disseminated toxoplasmosis in AIDS patients.

The usefulness of cell culture of bronchoalveolar lavage fluid for the diagnosis of toxoplasmosis in immunocompromised hosts has not been stressed previously. We report an acquired immunodeficiency syndrome patient with disseminated toxoplasmosis who was diagnosed by isolation of Toxoplasma gondii in cell cultures from bronchoalveolar lavage fluid.

AIDS-Related Opportunistic Infections↗

Problems in minimum inhibitory concentration determinations in coryneform organisms. Comparison of an agar dilution and the Etest.

The antimicrobial susceptibility of 159 coryneform organisms was determined by an agar dilution and Etest methods. Overall, the correlation between minimum inhibitory concentrations obtained by both techniques was good (> or = 0.09) for most antibiotics and organisms although the essential agreement ranged from 59% to 88.3%. Most organisms were equally categorized (sensitive, intermediate, or resistant) by both methods with only 0.2%, 0.4%, and 3.5% of very major, major or minor discrepancies, respectively. Such percentages dropped significantly when discrepant strains were retested. The correlation was specially good for Corynebacterium jeikeium and Corynebacterium urealyticum.

Actinomycetales↗

Development of myelopathy before herpes zoster rash in a patient with AIDS.

We describe the case of a patient with AIDS who developed progressive myelopathy due to varicella-zoster virus 2 months before the appearance of skin lesions typical of herpes zoster. Varicella-zoster virus was isolated from his CSF. Therapy with acyclovir failed to control his neurological complications despite its in vitro efficacy against the isolates.

AIDS-Related Opportunistic Infections↗

[Candida endocarditis in non-addict patients: a disease with high mortality. A clinico-pathological study of 3 cases].

Candida endocarditis is a rare infection which occurs under particular epidemiological circumstances, such a drug addiction, immunosuppression, prolonged intravenous therapy and valvular replacement surgery. Diagnosis requires a high suspicious index and is based on the demonstration of the organism in cardiac vegetations, peripheral embolisms or in positive blood-cultures; also when valvular insufficiency murmurs, embolic phenomena and echocardiogram-proved vegetations are present. In spite of antifungal therapy and valvular replacement, the mortality rate in Candida endocarditis is still higher than 80%. Three new cases of the entity are here reported stressing the diagnostic and therapeutical difficulties.

Aged↗

Cytopathic effect mimicking virus culture due to Mycobacterium tuberculosis.

Mycobacterium tuberculosis grew, from a bronchoalveolar lavage of a patient with AIDS, on a gentamicin-supplemented cell culture monolayer, causing a focal and slowly spreading cytopathic effect resembling that of a virological isolate. The same effect was observed after inoculation of two different inocula of M. tuberculosis onto the same cell culture.

Acquired Immunodeficiency Syndrome↗

[Disseminated histoplasmosis in AIDS patients. A study of 2 cases and review of the Spanish literature].

The characteristics of two cases of histoplasmosis in AIDS patients in our institution are presented together with a review of the 11 cases published in Spain since 1988 in addition to the current knowledge on histoplasmosis in patients with human immunodeficiency virus infection (HIV). In all except 2 of the 13 patients there was epidemiologic history of a stay in a country in which histoplasmosis is endemic. The 12 cases described in which this information is available had CD4 counts under 100/microL. The clinical manifestations of presentation were fever (92.3%) associated or not with other unspecific symptoms (asthenia, anorexia, cough, diarrhea) with a subacute course of two or three months. Physical examination demonstrated hepatosplenomegaly in 76.9% of the cases and 61.5% of the patients presented cutaneous lesions. Thoracic radiography was abnormal in 55% (61.5% had respiratory symptoms). Diagnosis was achieved by isolation of the fungus in the cutaneous biopsies in all the patients with dermatologic involvement and in 7 cases identification was performed in the bone marrow. In all the cases induction treatment was with anphotericin B and in those who reached the maintenance phase itraconazol was used in 7 cases and ketoconazol in one case. None of the patients treated with itraconazol, including the two in our center, presented recurrence at the time of completion of follow up. In conclusion, histoplasmosis is frequently presented as a prolonged febrile syndrome with unspecific characteristics, thus emphasizing the importance of including travel history to other countries in the anamnesis. The increase in journeys to endemic countries and immigration from these areas had led to an increase in the number of cases of histoplasmosis in patients with HIV infection in Spain.

AIDS-Related Opportunistic Infections↗