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J de Gracia

Publications and source records attributed to J de Gracia.

At least 19 recordsLinked to original sources
PubMed1997

[A contagiousness study in 3071 familial contacts of tuberculosis patients].

BACKGROUND: The study of contacts of patients with tuberculosis is an important preventive measure which helps to identify the risk factors for contagion, to detect new cases of the disease early and to break the epidemiological chain of transmission. MATERIAL AND METHOD: Three thousand and seventy-one contacts of 635 patients with tuberculosis were studied in our department over a period of 6 years. With the aid of uni- and multivariate analyses we established the importance of different factors in the appearance of tuberculous disease and infection in contacts. RESULTS: There were 1,341 tuberculin positive contacts (44%). The proportion increased in relation to the degree of the relationship and the bacillary density of the index case. A hundred and seventy-six new cases of tuberculosis were diagnosed among the contacts (5.7%). To study the risk factors for contagion, we analyzed the characteristics of 322 patients with positive sputum smears and their 1,623 contacts; 124 new cases were diagnosed among them (124/176; 70%). The most important factors for contagion in the multivariate analysis were the closer relationship (odds ratio [OR] = 8.32; confidence interval [Cl] 95% = 3.9-17.6), greater TST reaction of contacts (OR = 4.43; Cl 95% = 2.5-7.7), presence of more than 10 bacilli per microscopic field in the sputum samples of the index case (OR = 1.97; Cl 95% = 1.1-3.3), male contacts (OR = 1.86; Cl 95% = 1.2-2.7) and those younger than 15 years (OR = 1.58; Cl 95% = 1.01-2.45). Conversely, the sex of the index case and the history of previous tuberculosis in contacts did not influence the contagion. CONCLUSIONS: The study of contacts offers a high yield in the diagnosis of new tuberculosis cases, because the incidence of the disease is much higher than that of the general population. Moreover, it allows the detection of newly infected subjects in whom the application of chemoprophylaxis prevents the development of the disease, and thus the epidemiologic chain of transmission is broken.

Adolescent↗
PubMed1997

Characterization of specific immunoglobulin G (IgG) and its subclasses (IgG1 and IgG2) against the 23-valent pneumococcal vaccine in a healthy adult population: proposal for response criteria.

The aim of the study was to standardize an enzyme-linked immunosorbent assay (ELISA) method for the quantification of immunoglobulin G (IgG) and its subclasses (IgG1 and IgG2) against the 23-valent pneumococcal vaccine and to establish the criteria for a normal response to the vaccine. Forty healthy individuals (20 women and 20 men; mean age, 29 years) were studied. All were vaccinated with the 23-valent pneumococcal vaccine; blood samples were drawn just prior to and 3 weeks after immunization. Quantification of specific IgG and its subclasses was performed by an ELISA with the vaccine as the antigen. The linearity of the ELISA method was demonstrated by the similar slopes of the linear regression lines generated from the titration of sera with different antibody concentrations. The specificity of the antibodies against the vaccine was demonstrated by (i) an absorption test with pneumococcal vaccine, (ii) a cross-reactivity experiment with Haemophilus influenzae type b polysaccharide, and (iii) affinity chromatography with protein A-Sepharose. Response to the vaccine was defined by using the lower level of the 90% probability interval (one-tailed) for postimmunization-specific IgG, IgG1, and IgG2. By using this cutoff, responders were considered to be those with an absolute increase in antibody titers higher than 395 arbitrary units/ml for IgG, 0.350 A450 units for IgG1, and 0.314 A450 units for IgG2. Overall, 20 (50%) subjects had IgG, IgG1, and IgG2 responses, 9 (22.5%) had IgG and IgG2 responses, 4 (10%) had IgG1 responses, 3 (7.5%) had IgG and IgG1 responses, and 4 (10%) were nonresponders. Ninety percent of our population responded to the 23-valent pneumococcal vaccine. Up to 10% of healthy individuals may respond to an IgG subclass without significant increases in total IgG titers. The ELISA method that is described may be useful for evaluating the specific antibody response against polysaccharides.

Adult↗
PubMed1997

Increased risk of tuberculosis transmission in families with microepidemics.

In the present study, we analysed: 1) prevalence of TB infection and incidence of disease among family contacts of a cohort of patients with TB; 2) differential characteristics of families with microepidemics and families with < or = 1 new case of TB; and 3) efficacy of chemoprophylaxis in this group of contacts. Three thousand and seventy one family contacts of 635 patients with TB were studied. The study consisted of tuberculin skin testing and chest radiography in all cases, and bacteriological studies when active disease was suspected. Contacts were classified as belonging to: families with microepidemics (FME) (those with > or = 2 new cases of TB); families with one new case; and families with with no new cases. Chemoprophylaxis was prescribed in contacts following standard recommendations; all were followed up for 12-18 months. Rates of TB infection and disease among families, as well as the incidence of TB disease between those compliant and noncompliant with chemoprophylaxis were compared. Among the 3,071 contacts, 1,264 (41%) were infected and 176 (6%) had TB. Twenty two families with FME (3%) yielded 55 new cases of TB. The prevalence of infection (excluding the TB cases) was 80% in families with FME, 52% in families with one new case, and 41% in families with no new case (odds ratio (OR) 3.7; 95% confidence interval (95% CI) 2.1-6.5). Sputum smears were positive in 53% of cases in FME and 24% in non-FME families (OR 3.4; 95% CI 1.7-6.5). Bronchial sample cultures were positive in 84% of patients from FME families but in only 40% of those from non-FME families (OR 7.5; 95% CI 3.6-15.8). Chemoprophylaxis was prescribed in 356 contacts, of whom 296 complied and generated only one new case of TB, whilst there were 13 new cases among the 60 who did not comply (OR 81.6; 95% CI 26.7-248.7). This study showed the prevalence of infection and incidence of tuberculosis among family contacts of patients with newly diagnosed tuberculosis to be very high. A small number of families with microepidemics accounted for most new cases of tuberculosis, which were also more infectious. The extremely high risk of transmission in these families, together with the proven efficacy of chemoprophylaxis, justifies prescription of chemoprophylaxis to all their members, regardless of age.

Adult↗
PubMed1996

[Theophyllines of 12- and 24-hour sustained-release. Comparative study].

To compare 24-h and 12-h delayed-release theophylline in asthmatic patients, in terms of clinical stability and respiratory function, side effects and required dose, clinical tolerance and plasma concentrations. Patients with bronchial asthma in stable phase taking theophylline every 12 h were selected. Each patient received 12-h (treatment A) and 24-h (treatment B) theophylline formulas in a prospective, cross-over study with paired data for periods of 15 days. We evaluated theophylline doses, blood levels, clinical course, lung function and side effects. Twenty patients were enrolled. No significant differences between the two treatments were observed in mean dose of theophylline per kg body weight required to obtain therapeutic plasma concentrations (treatment A: 9.36 +/- 1.88 mg/kg/day; treatment B: 9.6 +/- 1.7 mg/kg/day). Mean blood level just before administration of a the next dose was lower with the 24-h formula, but still within therapeutic margins (treatment A: 7.31 +/- 2.27 micrograms/ml; treatment B: 10.66 +/- 2.86 micrograms/ml; p = 0.002). There were no differences in side effects after the adjustment period or in FEV1 after each treatment period. Peak expiratory flow remained stable during the study. The 24-h delayed release theophylline formula was similar to the 12-h formula in dose required by asthmatic patients and in therapeutic plasma concentrations throughout the day.

Adult↗
PubMed1995

[IgG subclasses in patients with symptomatic IgA deficiency].

BACKGROUND: Patients with IgA deficiency may be asymptomatic or may present recurrent infections mainly respiratory. A possible explanation for this variety of symptoms may be the association with a deficiency of IgG subclasses. METHODS: Twenty-five patients with a symptomatic IgA deficiency with a mean age of 18 +/- 12 years were studied. The quantification of the IgG subclasses was performed by ELISA test with antisubclass specific monoclonal murine antibodies. Serum from 100 healthy adults was collected to determine normal values of the IgG subclasses. RESULTS: Twenty-five (48%) had a deficiency of associated IgG subclasses (6 IgG2 deficiency, 1 IgG3, 3 IgG4 and 2 combined deficiency). The patient with a deficiency of associated IgG subclasses had more recurrent respiratory infections (chi 2, p < 0.03) and pneumonias (chi 2, p < 0.04). This group also had a greater FEV1 alteration (Student-t test, p < 0.04). CONCLUSIONS: Patients with symptomatic IgA deficiency frequently present IgG subclass deficiency and are more likely to have recurrent respiratory infections and greater changes in pulmonary function.

Adolescent↗
PubMed1995

[The use of human gamma globulin in the treatment of common variable immunodeficiency].

BACKGROUND: The indication for treatment with human gammaglobulin in patients with primary hypogammaglobulinemia is well established. Nonetheless, there are no uniform criteria with regard to dose, periodicity and route of administration. METHODS: Twenty-seven patients with common variable immunodeficiency (CVI) who received i.m. or i.v. treatment with gammaglobulin were studied, evaluating the secondary effects, stable levels of IgG achieved, control of symptomatology, clinical evolution and the need for adjuvant therapies. RESULTS: Intravenous administration was more effective than intramuscular administration to achieve higher total IgG serum levels (5.2 +/- 1.2 vs 3.5 +/- 1.6 g/l; p = 0.07) in a shorter period of time (2.1 +/- 1.6 months vs 6.3 +/- 2.8 months; p < 0.01) and with new few secondary effects. The dose and periodicity of the treatment was individualized in each patient on the basis of the needs of consumption and the speed of metabolism of the gammaglobulin, with patients with chronic bronchial suppuration and diarrhea being those requiring the greatest doses (p < 0.0001) and a short interdosis time interval (19.2 +/- 3.1 vs 23.6 +/- 3.6 days; p = 0.01). Treatment with human gammaglobulin allowed the control of recurrent bacterial infection; however, adjuvant treatment with respiratory physical measures and antibiotics were required in patients with chronic bronchial suppuration to avoid progressive alteration of respiratory function. CONCLUSIONS: The administration of human gammaglobulin at adequate doses and frequency is effective to control infection, avoid the development of chronic bronchial disease, alteration of pulmonary function and the appearance of other complications. Intravenous route is safer and produces fewer secondary effects than intramuscular administration with the doses and period of the treatment requiring individualization for each patient.

Adolescent↗
PubMed1995

[The use of fibrinogen-thrombin via endoscope in the treatment of massive hemoptysis].

We assessed the efficacy of fibrinogen-thrombin instillation through the fiberoptic bronchoscope to treat massive hemoptysis in patients to whom embolization of bronchial arteries was not available, was contraindicated or had failed. The fibrinogen-thrombin solution used was Tissucol, which in addition to 2% fibrinogen and 4 U/ml of thrombin, also contained factor XIII an aprotinin. The fibrinogen-thrombin solution was instilled with the aid of the Duplojec system and a 70 cm x 2 mm 4-way catheter. In 53 of the 628 fiberoptic bronchoscopies performed during the study, the indication was hemoptysis > or = 150 ml/12 h. Of these, bronchoscopic instillation of fibrinogen-thrombin was indicated in 5 cases because bronchial artery embolization was impossible. The point of bleeding was located by bronchoscopy in all cases and fibrinogen-thrombin instillation controlled hemoptysis immediately and throughout the follow-up period, which ranged 4 to 10 months. Morning expectoration of blood (< 10 ml) was observed in only 1 patient in the 3 days after treatment. The mean time taken for bronchoscopic exploration was 3 minutes (range, 2-7). In all cases fiberoptic bronchoscopy was performed without complications that might have required the procedure to be suspended. We conclude that the local use of fibrinogen-thrombin or fibrin glue instilled through the fiberoptic bronchoscope to the point of bleeding is a simple, fast and cheap way to control massive hemoptysis on a short and long-term basis.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1994

[Evaluation of replacement therapy in emphysema caused by alpha 1-antitrypsin deficiency].

Assessment of alpha 1-antitrypsin replacement therapy (AAT) for emphysema. Patient characteristics were analyzed along with the possible side effects of the treatment and its efficacy in maintaining appropriate AAT blood levels. Lung function changes were also studied. The treatment protocol began with 4 weekly intravenous doses of 60 mg/kg AAT (Prolastin) and continued with monthly doses of 240 mg/kg. AAT serum levels were measured before each dose. Every 6 months pulmonary function tests (spirometry, plethysmography and CO transfer) were performed. Thirteen patients (mean age 46 yr) have been studied since 1988. Mean initial FEV1 was 0.79 l. Over 250 doses have been infused with no significant side effects reported. AAT levels before treatment in 3 patients were lower than that considered protective (50 mg/dl). Function tests results indicated stabilization of spirometric values in most cases. Diagnosis of AAT deficiency is delayed considerably, meaning that significant functional deterioration takes place before replacement therapy begins. No side effects of treatment have been observed. Until an appropriate interval between doses has been established, each patient's AAT levels must be monitored.

Adult↗
PubMed1994

Scintigraphy, angiography and computed tomography in unilateral hyperlucent lung due to obliterative bronchiolitis.

This study examines the value of different imaging methods in assessing the anatomic structures of unilateral hyperlucent lung due to obliterative bronchiolitis. We studied 9 patients, 5 males and 4 females, suffering from UHL (mean age 49 years). Ventilation-perfusion scan (VPS) and computed tomography (CT) of the chest were performed in all, and conventional angiography or digital substraction angiography (DSA) in 7 patients. The VPS showed the characteristic pattern of a matched ventilation-perfusion defect and considerable air trapping during the washout phase. Conventional angiography and DSA displayed a smaller pulmonary artery on the affected side, with a poor peripheral vasculature. CT displayed a loss of lung volume in all cases, with diminished mean attenuation values, a markedly diminished vasculature and integrity of the main airways. In contrast to other imaging modalities, CT imaged bronchiectasis, which was the cause of the patients' clinical symptoms of bronchorrhea and hemoptysis. We conclude that CT of the chest is the most valuable imaging method for evaluating unilateral hyperlucent lung, particularly in symptomatic patients.

Adult↗
PubMed1994

Image analysis of hemosiderin-laden macrophages in bronchoalveolar lavage fluid.

The aim of this study was to assess quantitatively the relationship between the number of iron-laden macrophages, extent of hemosiderin content and amount of dark-stained hemosiderin clumps in bronchoalveolar lavage (BAL) fluids. The series included specimens from 20 subjects whose BAL had yielded iron-laden macrophages. Six had developed hemoptysis 3-15 days prior to BAL. Quantitative studies were performed on smears stained by the ferrocyanide reaction, using true color image analysis for image segmentation. A top-hat function based on mathematical morphologic concepts was used for extraction of dark clumps of hemosiderin. The results demonstrated the presence of iron-laden macrophages three days after hemoptysis. There was a moderate correlation between the percentage of macrophages and amount of hemosiderin content, but the extent of dark-stained clumps did not increase in parallel to the increase in hemosiderin content and probably represented an advanced stage in the phagocytic processing of hemosiderin formed from engulfed red blood cells. The main difference between subjects with and without previous hemoptysis was higher values for dark clumps of hemosiderin in the former.

Adult↗
PubMed1993

Diagnostic value of bronchoalveolar lavage in peripheral lung cancer.

A prospective study has been performed to assess the value of the addition of bronchoalveolar lavage (BAL) to the routine bronchoscopic exploration with bronchial washing (BW) and postbronchoscopy sputum (PBS) procedures in the diagnosis of peripheral primary lung cancer not visible through bronchoscope when fluoroscopic guidance is not available. BW, BAL, and PBS were performed in 67 patients with suspected primary lung cancer by peripheral lung lesion on chest radiograph (39 nodules and 28 infiltrates) and nonendoscopically visible lesion. The sequence of procedures was in all cases BW, BAL, and post-bronchoalveolar lavage bronchoaspirate (PBBA). An attempt was made to collect early morning postbronchoscopy samples of sputum (PBS) on 3 consecutive days. BW and PBBA were collected in the same test tube, and the cytologic result was considered as BW diagnostic yield. If there were negative bronchoscopic results, either percutaneous fine-needle aspiration or open-lung biopsy were performed for diagnosis. Fifty-five patients were found to have malignant disease (23 adenocarcinomas, 22 squamous cell carcinomas, six small cell carcinomas, and four bronchioloalveolar cell carcinomas). BAL was positive in 18 of the 55 (33%) carcinomas, and it gave the only positive result in six (11%). BW was also positive in 18 of the 55 (33%), but it gave positive results in only 3 (5%). PBS was positive in 13 of the 43 (30%) patients from whom samples could be spontaneously obtained and were suitable for cytologic examination (not consisting of saliva), and gave the only positive result in three (7%).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗