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Biomedical subjects

M Alvarez

Publications and source records attributed to M Alvarez.

At least 325 records · Page 18Linked to original sources
PubMed1990

Risk factors for fecal colonization with trimethoprim-resistant and multiresistant Escherichia coli among children in day-care centers in Houston, Texas.

In a previous study, we found fecal colonization with multiresistant Escherichia coli exhibiting high-level trimethoprim resistance in 19% of diapered children attending six day-care centers in Houston, Tex. To examine the potential risk factors associated with this finding, we conducted cross-sectional studies among 203 children attending 12 day-care centers, 51 children attending a well-child clinic (controls), and 64 medical students. The prevalence of fecal colonization with trimethoprim-resistant E. coli among children attending day-care centers (30%) was higher (P less than 0.001) than among control children (6%) or medical students (8%). The prevalence of colonization among the children attending the 12 centers ranged from 0 to 59% and was correlated with the number of diapered children enrolled (r = 0.73; P less than 0.01). In a case control study among the day-care center children, significant risk factors were an age of less than 12 months and attendance at a center with an enrollment of over 40 diapered children (odds ratios of 2.2 and 3.5, respectively); ethnicity, duration of attendance, and prior antibiotic administration were not associated with colonization. Plasmid analysis of 60 of the day-care center strains revealed 22 profiles, each of which was unique to a given day-care center. Transmission and carriage of trimethoprim-resistant strains for as long as 6 months was documented in one center studied on three occasions. Given the documented transmission of enteric pathogens among diapered children attending day-care centers and their spread into family members, it is likely that day-care centers are an important community reservoir of plasmid-associated antibiotic-resistant E. coli.

Adolescent↗
PubMed1990

Dot ELISA for direct detection of BK virus in urine samples.

The dot ELISA technique was applied for direct detection of BK virus in clinical urine samples. The assay was performed on nitrocellulose paper dotted with the polyethylene glycol precipitated urine samples free of cellular debris. BK virus was detected with an anti-BK virus monoclonal antibody, and the complex was visualized by immunoperoxidase staining. Positive reaction appeared as well-defined dark blue spots. Of the 110 urine samples examined, 31 were positive in the dot ELISA and 79 proved negative. Comparing with the IIF results, the dot ELISA had a 88.46% of sensibility and 90.4% of specificity, and the results agreed completely in 99 samples. The simple dot ELISA technique can be recommended for detection of BK virus excretion in routinary diagnostic.

Animals↗
PubMed1990

[Microbiological study of 30 samples of heroin].

In the present study, 30 samples of heroin from material seized by the police in Vizcaya from 7-1-1987 to 6-30-1988 were investigated. Bacillus spp were isolated in 19 samples (63.3%), coagulase negative staphylococci in 14 (46.6%), Aspergillus in 3 (10%) and S. aureus in one (3.33%). In addition, chemical analysis of the purity of heroin was carried out with gas chromatography. The purity of the samples ranged from 1.1% to 94.3%. No relation was found between the weight of the sample, its purity and its degree of microbiological contamination. In the microbiological study of 4 lemons used to dissolve the drug, Candida krusei was isolated from three samples, Aspergillus in two and Geotrichum in one.

Aspergillus↗
PubMed1990

High-dose intravenous gamma globulin: does it have a role in the treatment of severe erythroblastosis fetalis?

The role of high-dose intravenous (IV) gamma globulin in the treatment of erythroblastosis fetalis was assessed in five pregnancies with severe Rh (four) or Kell (one) isoimmunization. These women were treated with IV gamma globulin (1.0 g/kg body weight) once a week. In addition, fetal blood transfusions were performed when indicated. In four patients with Rh sensitization, high-dose IV gamma globulin treatment had no apparent effect on the total number of intrauterine transfusions required, the interval between transfusions, or the volume of blood required at each transfusion. The treatment did not prevent fetal hydrops and had no effect on maternal antibody titers. In one patient with Kell sensitization, however, the course of the disease was less severe than anticipated, suggesting that IV gamma globulin treatment may have modified the severity of the disease. We conclude that high-dose IV gamma globulin does not appear to be useful in the treatment of severe Rh disease. Its role in Kell and other types of red-cell isoimmunization deserves further evaluation.

Adult↗
PubMed1990

[Evaluation in our milieu of an ELISA method (ANDA-Tb) for the serological diagnosis of tuberculosis].

We have evaluated the new ELISA test (ANDA-Tb) for the serological diagnosis of tuberculosis in serum samples from 343 individuals: 160 were from blood donors, 152 from patients with nontuberculous diseases, most of them respiratory, and 31 from tuberculous patients diagnosed by positive culture. Using a cutoff value in 350 serounits we had a positive predictive value of 57% and a negative predictive value of 98% in blood donors, and 43% and 97%, respectively, in control patients. Sensitivity was 68%. There was a higher false positive rate in patients with respiratory diseases, particularly acute pneumonia. We conclude that this particular ELISA is very useful as a supportive test for the diagnosis of tuberculosis, with a lower specificity in hospital nontuberculous patients.

Antibodies, Bacterial↗
PubMed1990

[Munchausen's syndrome: a study of 6 cases].

We report 6 patients with Munchausen syndrome, a fictitious disorder with physical symptoms. There were 4 females and 2 males, the age ranged from 21 to 29 years. Abdominal pain (2), hemoptysis, shock and hypoglycemia were the presenting symptoms. The diagnosis was made after a prolonged and costly hospital course, including invasive and non invasive diagnostic procedures. Two patients were ill enough to be at risk of death. An early diagnosis may help prevent unnecessary or risky procedures in these patients.

Adult↗
PubMed1990

First-trimester transabdominal multifetal pregnancy reduction: a report of 85 cases.

Eighty-five cases of multifetal pregnancy reduction were performed transabdominally at 9.5-13 weeks' gestation. All pregnancies consisted of three or more fetuses (28 triplets, 47 quadruplets, four quintuplets, four sextuplets, one septuplet, and one nontuplet), and all except five were reduced to twins. Forty-five women have delivered viable infants and eight lost all of the fetuses; 32 pregnancies are ongoing. No temporal relationship was noted between the pregnancy losses and the procedures. The mean gestational age at delivery was 35.7 weeks; 16 women (35.5%) delivered at or after 37 weeks, 16 (35.5%) between 34.5-37 weeks, nine (20%) between 32-34.5 weeks, and four (9%) before 32 weeks. There were no perinatal deaths, and all infants are healthy except for one who developed sequelae of severe hyaline membrane disease.

Abortion, Induced↗
PubMed1990

Contemporary management of a potentially lethal fetal anomaly: a successful perinatal approach to epignathus.

Prenatal diagnosis of epignathus (a teratoma originating in the oropharynx) has been reported previously. However, in many of these cases the neonates succumbed to acute respiratory distress secondary to airway obstruction at the time of birth. We describe a case of antepartum diagnosis of epignathus using ultrasonography and magnetic resonance imaging as complementary techniques. The ability to accurately define the fetal anomaly permitted us to plan a unique strategy for peripartum management. After cesarean delivery of the infant from the uterus, the umbilical cord was not clamped and the fetoplacental circulation was left undisturbed. A tracheostomy was then performed, after which the umbilical cord was clamped and the infant was stabilized. Several hours later, a debulking procedure was performed in the operating room to remove the tumor from its attachment to the bony palate. Both mother and infant did well postoperatively. The ability to plan and perform a controlled tracheostomy while the infant remained oxygenated and ventilated proved to be lifesaving in this case.

Adolescent↗
PubMed1990

Intrauterine intravascular transfusion for severe erythroblastosis fetalis: how much to transfuse?

Intrauterine intravascular transfusion is now believed to be a more precise method for treating fetal anemia in erythroblastosis fetalis than is intraperitoneal transfusion. Previously established guidelines for the volume of blood to be given in intraperitoneal transfusion at a specific gestational age are not applicable for intravascular transfusion. In 28 patients, intravascular transfusion was performed on 81 occasions between 19-34 weeks' gestation. The total number of transfusions ranged from one to six per patient. The aim at each procedure was to achieve a final hematocrit of 35-50%. Factors examined as likely to determine the volume of blood required included pre-transfusion hematocrit, post-minus pre-transfusion hematocrit (hematocrit increase), the hematocrit of the transfused blood, gestational age, estimated fetal weight, and interval from last transfusion. The factors found to be most predictive of total volume of blood required for transfusion were the hematocrit increase and either estimated fetal weight or gestational age.

Blood Transfusion, Intrauterine↗
PubMed1989

Antibodies against Trichosporon beigelii in vaginal washings from asymptomatic women.

Trichosporon beigelii was isolated from vaginal washings from three asymptomatic women. All three women had IgG or IgA anti-T. beigelii antibody titres greater than or equal to 20 when tested by an indirect immunofluorescence assay against the three strains isolated. Titres greater than or equal to 160 were found when each patient was tested against her own isolate. Patients with Candida albicans vulvovaginitis, or from whom C. albicans or Toruloposis glabrata was isolated from vaginal washings, or who had negative cultures for yeasts, had titres less than or equal to 20.

Antibodies, Fungal↗
PubMed1989

[Glucose overload test. Screening of gestational diabetes in population of pregnant women with risk factors for diabetes. Clinical experience].

UNLABELLED: Clinical utility of the Overload Test with 50 g. of Oral Glucose (PSG) is evaluated, in 513 pregnancies with risk factors for diabetes. Of the 933 PSG which were made, 13.7% were positive (limit value: plasma glucose of much less than 150 mg/dl at 1 hour); the test were made after 20 weeks of gestation in 82.8% of the cases. Of the 128 positive PSG, 73 positive Oral Glucose Tolerance Test were obtained (O'Sullivan criteria). The prevalence of gestational diabetes found in this group was 15.2%. There was no difference on the most frequent risk factors (family history, obesity and macrosomia) between the general population in the study and the group of Gestational diabetes. CONCLUSION: PSG, because of its easy application, low cost and excellent tolerance is a test which should be included among the prenatal routine test as screening for gestational diabetes in our media.

Adult↗
PubMed1989

[Severity evaluation system: APACHE II, SAPS. National experience in a unit of medical intensive therapy].

We evaluated 2 new prognostic indices, APACHE II and SAPS, in 533 consecutive patients admitted to a general hospital clinical care unit. Mortality was 19.5% (13.1% in the ICU). Among non-survivors 80% had a greater than = 20 APACHE II score and 77% a greater than = 13 SAPS score. Only 2% of patients with APACHE score less than 10 or SAPS less than 7 died. A good correlation with previously used indices (APACHE I and TISS) was 0.6. Utilization of these prognostic indices allows comparison of reports from different centers, evaluation of early and long term prognosis and a help in making cost-benefit decisions.

Chile↗