RESUMEN
The results of the quantitative culture of sputum samples from patients with bronchiectasis were compared with those obtained in the same samples with the detection of antibody-coated bacteria (ACB), in the acute phase of the disease (group I), after antibiotic therapy (group II), and in the phase of clinical stability (group III). In quantitative cultures at least one potentially pathogen species was isolated, at a concentration of greater than or equal to 10(6) colony forming units/ml in the 7 sputum samples from group I, in 4 of the 5 samples from group II, and in 10 of the 11 samples from group III. The immunofluorescence technique detected ACB in all samples from group I and group II, and in 10 of the 11 from group III. The sample from group III in which ACB were not detected was the same in which potentially pathogen organisms were not detected by culture.
Asunto(s)
Anticuerpos Antibacterianos/análisis , Bacterias/aislamiento & purificación , Bronquiectasia/microbiología , Esputo/microbiología , Enfermedad Aguda , Adulto , Antibacterianos/uso terapéutico , Bacterias/inmunología , Técnicas Bacteriológicas , HumanosRESUMEN
Assessment of the anterior rhinomanometry on 9 normal persons with the aim to know the variations between several individuals and in each one. The examination, performed on 3 consecutive days, showed a great interindividual variability and an acceptable individual variability. Accordingly the AA. recommend to realize the test in all but on the same subject, in series because of the wide interpersonal variability verified, specially when the number of cases is short.
Asunto(s)
Manometría/estadística & datos numéricos , Nariz/fisiología , Ventilación Pulmonar/fisiología , Análisis de Varianza , Humanos , Manometría/métodosRESUMEN
Respiratory and skeletal (deltoid) muscle strength were evaluated in 34 oral steroid-dependent asthmatics by use of maximal inspiratory and expiratory pressures and a myometer. The patients were compared to age- and sex-matched asthmatics who had never been on continuous oral steroid treatment. Endurance time was also studied in ten steroid-dependent asthmatics and ten controls using a pressure threshold breathing device. Nutritional status was assessed from body weight, midarm circumference, triceps skinfold (TSF), prealbumin, albumin, and total protein. An open biopsy from deltoid muscle was taken from nine steroid-dependent asthmatics and the diameter of type 1 and type 2 fibers was measured by a morphometric study. No differences were found between study and control groups either in respiratory and skeletal muscle strength or in endurance time. Steroid-dependent asthmatics showed a decrease in TSF, total protein, albumin, and potassium serum levels when compared with the control group but differences were not statistically significant after Bonferroni's adjustment for multiple comparison studies. Transversal diameter of type 2 fibers was significantly correlated with the percentage of ideal weight (r = 0.75 p less than 0.05), but not with average daily dose of steroids nor with the length of steroid treatment. Our results support the clinical impression that steroids, at the doses usually administered in chronic severe asthma, do not cause muscular weakness. We also found that malnutrition rather than corticosteroids is the most important contributory factor to type 2 muscle fiber atrophy in steroid-dependent asthma.
Asunto(s)
Asma/tratamiento farmacológico , Glucocorticoides/uso terapéutico , Músculos/fisiopatología , Músculos Respiratorios/fisiopatología , Adulto , Anciano , Asma/patología , Asma/fisiopatología , Femenino , Volumen Espiratorio Forzado , Glucocorticoides/efectos adversos , Humanos , Masculino , Persona de Mediana Edad , Contracción Muscular/efectos de los fármacos , Músculos/efectos de los fármacos , Músculos/patología , Estado Nutricional , Resistencia Física , Capacidad VitalRESUMEN
A total of 77 consecutive patients submitted to mechanical ventilation (MV) for greater than 48 h in a respiratory ICU (RICU) were studied to investigate the incidence, etiology, and consequences of ventilator-associated pneumonia. Eighteen (23%) patients developed a bacterial pneumonia after 5.6 +/- 1.0 days (mean +/- SEM; range 2 to 17) of MV. Three additional cases were demonstrated at autopsy, raising the incidence to 27%. Overall, the mean duration of MV increased from 9.7 +/- 0.9 to 32.2 +/- 5.1 days (p less than .0001) when pneumonia developed. A longer period of hospital stay before RICU admission and the presence of chronic obstructive pulmonary disease were significant characteristics of patients with pneumonia when compared to patients without nosocomial pulmonary infection. One or more etiological agents were identified in 14 patients from the pneumonia group by means of a highly specific technique (protected brush catheter, transthoracic needle aspiration, pleural fluid, and/or blood cultures). The predominant pathogens isolated were Gram-negative bacilli (Acinetobacter sp. and Pseudomonas sp.). Half of the cases were polymicrobial. Compared to other series, our results may reflect with more accuracy the actual incidence of nosocomial pneumonia in mechanically ventilated patients, since we used highly accurate techniques along with autopsy findings which allowed us to confirm or discard the diagnosis of bacterial pneumonia.
Asunto(s)
Infección Hospitalaria/etiología , Neumonía/etiología , Respiración Artificial/efectos adversos , Infección Hospitalaria/epidemiología , Infección Hospitalaria/microbiología , Infección Hospitalaria/mortalidad , Humanos , Unidades de Cuidados Intensivos , Persona de Mediana Edad , Neumonía/epidemiología , Neumonía/microbiología , Neumonía/mortalidad , Factores de Riesgo , EspañaRESUMEN
We compared the diagnostic value of quantitative cultures of bronchoalveolar lavage (BAL) and telescoping plugged catheter (TPC) samples in 34 nonimmunocompromised, mechanically ventilated (MV) patients with suspected bacterial pneumonia. A control group of seven "noninfected" MV patients was also studied. In 92% of patients with bacterial pneumonia (32 of 34), simple endotracheal aspiration samples recovered one or more microorganisms. Both BAL and TPC samples cultured colony-forming units (cfu) greater than or equal to 10(3)/ml of one or more microorganisms in 56% (19 of 34) of patients. TPC and BAL culture results agreed on 88.5% (54 of 61) of the recovered microorganisms. Sterile TPC and BAL cultures agreed on 80% (4 of 5) of the cases. Microorganisms cultured from blood samples were also cultured from BAL and TPC specimens. Culture results from the two techniques completely disagreed in only one case (3%). In the control group, one TPC and two BAL cultures yielded microorganisms in cfu greater than or equal to 10(3)/ml. Specificities of BAL and TPC were 71 and 86%, respectively, whereas specificity of endotracheal aspiration was only 14%. Both the bacterial index obtained by TPC and BAL, as well as the quantitative cultures, correlated moderately well (r = 0.78 and 0.72, respectively, p less than 0.001 for both correlations). BAL and TPC results caused changes of antibiotic treatment in 11 of 23 survivors. Neither BAL nor TPC caused complications. Our results demonstrate that BAL and TPC diagnose bacterial pneumonia in MV patients with similar accuracy. Culture results from both techniques showed excellent qualitative and reasonable quantitative agreement.
Asunto(s)
Bacterias/aislamiento & purificación , Líquido del Lavado Bronquioalveolar/microbiología , Cateterismo Periférico/instrumentación , Neumonía/etiología , Respiración Artificial , Adulto , Anciano , Bacterias/clasificación , Humanos , Persona de Mediana EdadRESUMEN
To determine the number of maximal mouth pressure manoeuvres needed to obtain a reproducible value of maximal inspiratory mouth pressure (MIP), we studied 44 patients with chronic airflow obstruction, with a mean (SD) % predicted FEV1 value of 53.9 (25), who were clinically stable. Maximal inspiratory mouth pressure was determined with an anaeroid manometer during maximal inspiratory efforts in a quasi static condition at residual volume. All patients performed 20 consecutive maximal inspiratory mouth manoeuvres, each one separated by 30-40 seconds. The mean (SD) values of MIP varied from 71.5 (25.5) cm H2O at the first measurement to 80.1 (27) cm H2O at the last measurement. Maximal values of MIP were usually achieved after nine determinations. It is concluded that to obtain a reproducible MIP value in patients with chronic airflow obstruction who are untrained and unexperienced in such manoeuvres a minimum of nine technically acceptable maximal mouth pressure manoeuvres should be performed.
Asunto(s)
Enfermedades Pulmonares Obstructivas/fisiopatología , Boca/fisiopatología , Pruebas de Función Respiratoria/métodos , Femenino , Humanos , Masculino , Manometría , Persona de Mediana Edad , PresiónRESUMEN
The cell preparations of 199 bronchoalveolar lavages (BAL) were reviewed to evaluate the meaning of the presence of mastocytes for the diagnosis of diffuse interstitial lung diseases. The study population consisted of 41 control individuals, 10 with extrinsic allergic alveolitis (EAA), 55 with sarcoidosis 38 with asbestosis, 25 with pulmonary fibrosis associated to collagen diseases, 18 with idiopathic pulmonary fibrosis and 12 with carcinomatous lymphangitis. Mastocytes were predominantly found in patients with EAA (8 of 10 cases) and in some cases of sarcoidosis and idiopathic pulmonary fibrosis. The rate of mastocytes in the patients with EAA was significantly higher than in the other groups (p less than 0.001). The presence of mastocytes in the BAL is particularly suggestive of EAA; rates higher than 3% are only found in this condition.
Asunto(s)
Líquido del Lavado Bronquioalveolar/patología , Enfermedades Pulmonares/patología , Mastocitosis/patología , Alveolitis Alérgica Extrínseca/patología , Asbestosis/patología , Humanos , Pronóstico , Fibrosis Pulmonar/patología , Sarcoidosis/patologíaRESUMEN
One or more tuberculin skin tests (PPD) were carried out in 1865 members of the health care staff (71%) of the Hospital Clinic from Barcelona, so as to detect the prevalence of the infection and, particularly, to identify the converters (recently infected individuals) for the recommendation of antituberculous chemoprophylaxis. A higher number of converters was found in the group with higher risk of contagion owing to professional exposure, but the differences were not statistically significant. Significant differences were not found, either, between infected and noninfected individuals classified in risk groups. In the 1865 surveyed individuals, the initial and successive (when performed) PPD testings were negative in 987 (52%). In 775 individuals (41%), PPD reaction was positive in the initial testing. In the remaining 103 (5%), PPD reactions became positive after an initial negative result (converters). 50% of the 775 individuals with positive PPD reaction were over 35 years of age. The rate of infected individuals (positive PPD reaction) and converters was not significantly higher in those health care professionals with a supposed higher degree of exposure to infection.
Asunto(s)
Fuerza Laboral en Salud , Tuberculosis/epidemiología , Adulto , Antituberculosos/uso terapéutico , Estudios Transversales , Humanos , España , Prueba de Tuberculina , Tuberculosis/prevención & controlRESUMEN
The value of differential cell counts in bronchoalveolar lavage fluid in patients who were serologically positive for the human immunodeficiency virus (HIV) was studied in 30 patients with classified into four groups according to the severity of illness: (1) seven subjects with the AIDS related complex without clinical or radiological evidence of pulmonary infection; (2) eight patients with the AIDS related complex and pulmonary tuberculosis; (3) eight patients with AIDS and Pneumocystis carinii pneumonia; and (4) seven patients with AIDS, Pneumocystis carinii pneumonia, and severe respiratory failure. All four groups had a similar percentage of lymphocytes, significantly higher than that of a control group of 15 healthy volunteers. A significant increase in the percentage of neutrophils was observed in groups 2, 3, and 4. The lavage fluid differential cell count does not therefore appear to help in the differential diagnosis of pulmonary infections in HIV positive patients. The abnormal percentage of lymphocytes observed in some patients with the AIDS related complex without clinical evidence of pulmonary infection suggests that lung injury may exist before clinical or radiological abnormalities develop. This might be related to an immunological mechanism or might be caused by an undetected subclinical infection.
Asunto(s)
Síndrome de Inmunodeficiencia Adquirida/patología , Líquido del Lavado Bronquioalveolar/patología , Recuento de Leucocitos , Complejo Relacionado con el SIDA/patología , Femenino , Humanos , Linfocitos , Masculino , Neutrófilos , Neumonía por Pneumocystis/patología , Tuberculosis Pulmonar/patologíaRESUMEN
In the present study the clinical efficacy and tolerance of josamycin (1 g every 12 hours) was prospectively evaluated for the empirical therapy of patients below 70 years with community acquired pneumonia of atypical presentation (AP), without respiratory failure, radiological cavitation or risk factors of pharyngeal colonization by gram-negative bacilli. During a 28-month period 168 patients adequate for the study were included. The etiological diagnosis was established in 56 cases (33.3%); in 55 by seroconversion (28 Mycoplasma pneumoniae, 22 Legionella pneumophila, 1 Chlamydia psittaci and 4 Coxiella burnetii) and in only one case by positive blood culture (Streptococcus pneumoniae). The mean duration of therapy was 9 days and that of fever 1.4 days. Five patients (3%) had mild transient gastrointestinal complaints. No patient required a change of therapy. Relapses were not observed in the 45 days of follow up. In conclusion, josamycin (1 g/12 h p.o.) is an effective and well tolerated antibiotic for the therapy of pneumonia by M. pneumoniae or L. pneumophila, and it represents a good empirical treatment of AP in patients below 70 years without risk factors of GNB infection, respiratory failure or radiological cavitation.
Asunto(s)
Leucomicinas/uso terapéutico , Neumonía por Mycoplasma/tratamiento farmacológico , Adolescente , Adulto , Anciano , Esquema de Medicación , Evaluación de Medicamentos , Eritromicina/uso terapéutico , Femenino , Humanos , Leucomicinas/administración & dosificación , Masculino , Persona de Mediana Edad , Estudios ProspectivosRESUMEN
The records of 92 asthmatics who underwent mechanical ventilation were reviewed. In seven patients (8%) the severe attack was precipitated by a non-steroidal anti-inflammatory drug (NSAID); one of these patients died. Five of the cases had a history of asthmatic attacks provoked by NSAIDs; whilst in two the severe attack requiring mechanical ventilation was the first manifestation of NSAID-intolerance. In two patients the NSAID had been prescribed by their physicians. Another aspirin-intolerant patient, a general practitioner, self-administered a NSAID. The sudden attack in another patient was precipitated by a preparation which contains aspirin and is usually recommended for indigestion. In the fatal case the attack was provoked by a capsule containing aspirin, which had been given by a herbalist. Unlike other reports, we found that NSAID-intolerance is a frequent provoking factor in severe acute asthma requiring mechanical ventilation. Inadequate investigation of precipitating factors in asthmatics with severe sudden attacks is a possible reason why this phenomenon is underreported.
Asunto(s)
Antiinflamatorios no Esteroideos/efectos adversos , Aspirina/efectos adversos , Asma/inducido químicamente , Hipersensibilidad a las Drogas/etiología , Estado Asmático/inducido químicamente , Ventiladores Mecánicos , Adolescente , Adulto , Anciano , Hipersensibilidad a las Drogas/terapia , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estado Asmático/terapiaRESUMEN
The outcome of 49 asthmatics (20 men and 29 women) who had suffered a severe exacerbation of asthma requiring mechanical ventilation was investigated in a follow-up study ranging from 23 weeks to 10 years. Over this time, there were 6 fatalities, all female chronic asthmatics requiring treatment with bronchodilators, beclomethasone, and short courses of oral steroids. Three died at home as a consequence of a sudden attack. Another patient developed a cardiorespiratory arrest immediately after having received a sedative. In the remaining two cases, death occurred within hours or days of progressive deterioration. Four of the six women had required psychiatric treatment for an anxiety-depression syndrome. These findings support previous studies suggesting that psychological disturbances may be predisposing factors to death in bronchial asthma.
Asunto(s)
Asma/mortalidad , Anciano , Ansiedad/complicaciones , Ansiedad/tratamiento farmacológico , Asma/complicaciones , Asma/terapia , Depresión/complicaciones , Depresión/tratamiento farmacológico , Femenino , Humanos , Masculino , Cooperación del Paciente , Factores de Riesgo , Factores SexualesRESUMEN
To evaluate the usefulness of anti-T6 monoclonal antibody cell analysis in the assessment of diffuse lung disease, 77 bronchoalveolar lavages (BAL) were performed on 70 subjects: 18 normal smokers, 14 normal nonsmokers, 30 patients with chronic interstitial lung diseases (15 sarcoidosis, 12 idiopathic or associated pulmonary fibrosis, 3 histiocytosis X) and 8 patients with diffuse lung neoplastic disorders. The percentage of T6-positive cells was significantly higher in normal smokers than in normal nonsmokers (p less than 0.05). Positive T6 cells were absent or less than 1% in normal subjects, in patients with interstitial lung diseases and in patients with diffuse lung cancer, except in a case of desquamative interstitial pneumonitis, who had 2% of reacting cells. In contrast, such cells were always 3% or higher in the 6 BAL performed in histiocytosis X patients (p less than 0.05).
Asunto(s)
Anticuerpos Monoclonales , Antígenos de Diferenciación de Linfocitos T/análisis , Líquido del Lavado Bronquioalveolar/análisis , Enfermedades Pulmonares/diagnóstico , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Fumar/metabolismoRESUMEN
The combination aztreonam + cefotaxime (AZ + CE) was compared to amikacin + cefotaxime (AM + CE) in the treatment of nosocomial pneumonia acquired at the intensive-care unit. This study included a total of 33 patients fulfilling criteria for nosocomial pneumonia. 16 of them were randomly allocated to the AZ + CE group and 17 to the AM + CE group. The empirical treatment was effective for 78% of AZ + CE cases and 92% of AM + CE cases (p = NS). Clinical care was observed in 77% of cases (10 out of 13 evaluable) in the AZ group and in 75% of the group treated with AM (12 cases out of 16 evaluable; p = NS). In the evaluable cases, treatment failure was associated with injections due to the following organisms: Acinetobacter calcoaceticus (1) and Pseudomonas aeruginosa (1) in the AZ group and A. calcoaceticus (1) in the AM group. Superinfections were observed only in the AM group P. aeruginosa. A. calcoaceticus, Streptococcus viridans, Candida albicans, Aspergillus fumigatus and Serratia marcescens. Both the peak and through serum concentrations of AZ and AM were maintained within normal ranges. Finally, an impairment of renal tubular function was observed in the group of patients treated with AM, as measured by urinary levels of N-acetyl-beta-D-glucosaminidase and leucine aminopeptidase sequentially during the treatment. These changes in renal functions alterations mentioned were not observed in the AZ group. It is concluded that the AZ + CE combination is an effective empirical and active antibiotic treatment against severe nosocomial pneumonia. Aztreonam has no renal toxicity, which is an advantage to take into account in patients with altered renal function.
Asunto(s)
Amicacina/administración & dosificación , Aztreonam/uso terapéutico , Cefotaxima/uso terapéutico , Infección Hospitalaria/tratamiento farmacológico , Neumonía/tratamiento farmacológico , Adulto , Anciano , Aztreonam/administración & dosificación , Cefotaxima/administración & dosificación , Ensayos Clínicos como Asunto , Quimioterapia Combinada , Femenino , Humanos , Unidades de Cuidados Intensivos , Masculino , Persona de Mediana Edad , Distribución AleatoriaRESUMEN
The immunoalkaline phosphatase procedure is described as a method for labelling bronchoalveolar lavage cellular specimens with monoclonal antibodies. This method has several advantages over conventional immunofluorescent techniques: it can be performed on cytocentrifuge preparations stored for long periods before staining; cell morphology can be observed in detail in positive and negative cells; the staining is permanent and stable, and, the reaction can be evaluated with a light microscope. Normal values for lymphocyte subpopulations in smokers and nonsmokers are also reported.
Asunto(s)
Antígenos de Superficie/análisis , Líquido del Lavado Bronquioalveolar/inmunología , Técnicas para Inmunoenzimas/normas , Fumar/inmunología , Adulto , Fosfatasa Alcalina , Anticuerpos Monoclonales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Linfocitos T Colaboradores-Inductores/análisis , Linfocitos T Reguladores/análisisRESUMEN
The usefulness of telescoping plugged catheter (TPC) together with bronchoalveolar lavage (BAL) in the same bronchoscopic act in the diagnosis of pulmonary infiltrates was studied in 113 fiberoptic bronchoscopic examinations performed on 96 immunocompromised patients. The TPC cultures detected pulmonary bacterial infections in 25 (22 percent) cases but showed a high frequency of false positive results (12 microorganisms, 27 percent). Bronchoalveolar lavage had an overall diagnostic yield of 49 percent (53 of 113 cases). Combining TPC and BAL diagnostic values, 78 of 113 pulmonary infiltrates (69 percent) were diagnosed. The results obtained by both techniques allowed us to modify the treatment in 35 (31 percent) cases. Combined, TPC and BAL show a good diagnostic yield in immunocompromised patients with pulmonary infiltrates. Both techniques should be performed as the first approach in the evaluation of these patients, and be done in the same bronchoscopic procedure.
Asunto(s)
Líquido del Lavado Bronquioalveolar/análisis , Broncoscopía , Cateterismo/instrumentación , Tolerancia Inmunológica , Enfermedades Pulmonares/diagnóstico , Bacterias/aislamiento & purificación , Líquido del Lavado Bronquioalveolar/microbiología , Broncoscopía/efectos adversos , Broncoscopía/métodos , Errores Diagnósticos , Hemorragia/diagnóstico , Humanos , Enfermedades Pulmonares Fúngicas/diagnóstico , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/secundario , Neumonía por Pneumocystis/diagnóstico , Neumonía Viral/diagnóstico , Tuberculosis Pulmonar/diagnósticoAsunto(s)
Drenaje , Percusión , Postura , Intercambio Gaseoso Pulmonar , Anciano , Cuidados Críticos/métodos , Femenino , Humanos , Enfermedades Pulmonares Obstructivas/sangre , Enfermedades Pulmonares Obstructivas/terapia , Masculino , Persona de Mediana Edad , Presión Parcial , Insuficiencia Respiratoria/sangre , Insuficiencia Respiratoria/terapiaRESUMEN
A new guiding technique, Metras catheter (MC), for blindly introducing a telescoping plugged catheter (TPC) was applied to 25 mechanically ventilated patients with suspected bacterial pneumonia (BPN). Results obtained with TPC-MC were compared with those obtained with TPC using a conventional fiberoptic bronchoscope (FB) in random order. The diagnosis of BPN was definitely confirmed in 18 patients. In 7 patients, all TPC samples (MC and FB) were sterile, and a diagnosis other than BPN was proved. In the former group, colony-forming units equal to or greater than 10(3)/ml of one or more microorganisms were obtained in 61% of TPC-MC and in 66% of TPC-FB samples. These percentages increased to 64 and 71%, respectively, when 4 patients with previous antibiotic treatment were excluded from the study group. Agreement was observed between microorganisms cultured from both TPC samples in 11 of 18 patients with proved BPN (61%). Complete disparity was seen only in 2 patients (11%). Two patients developed a self-limiting hemoptysis after the TPC procedure (MC and FB, respectively). We conclude that TPC-MC is both a sensitive and specific technique for the diagnosis of BPN in mechanically ventilated patients. Because the diagnostic value of TPC-MC is similar to that of TPC-FB, we propose that the MC be used in patients receiving mechanical ventilation when the FB is not available. The simplicity and lower cost of this new system are important advantages to be considered over the fiberoptic bronchoscope.
Asunto(s)
Infecciones Bacterianas/diagnóstico , Cateterismo/métodos , Neumonía/diagnóstico , Respiración Artificial , Adulto , Anciano , Broncoscopía , Cateterismo/instrumentación , Tecnología de Fibra Óptica , Humanos , Persona de Mediana Edad , Neumonía/microbiologíaRESUMEN
To analyse the pattern of pulmonary gas exchange during maximal exercise (Emax) in asbestosis, we compared nine subjects with this disease (1 female/8 male), aged 54 +/- 11 yrs (mean +/- SD), to nine patients (1 female/8 male) with idiopathic pulmonary fibrosis (IPF) of a similar age, height, weight and smoking history, both at rest and during Emax. No differences were observed in dynamic and static lung volumes between the groups. However, patients with IPF had a lower DLCOsb and KCO (p less than 0.005 and 0.05, respectively). At rest, both groups showed mild arterial hypoxaemia (76 +/- 11, asbestosis, vs 77 +/- 11 mmHg, IPF), widened AaPO2 (32 +/- 14 vs 31 +/- 13 mmHg) and slight increases in VD/VT (47 +/- 12 vs 46 +/- 11%), respectively. During Emax, PaO2 fell to 51 +/- 7 mmHg in patients with IPF whereas those with asbestosis had PaO2 of 73 +/- 21 mmHg (p less than 0.05). Conversely, those with asbestosis were able to reduce VD/VT (from 47 +/- 12 to 39 +/- 10%, p = 0.01) as opposed to those with IPF (from 46 +/- 11 to 47 +/- 13%). Furthermore, DLCOsb and AaPO2 during Emax were highly correlated only in IPF (r: -0.84, p less than 0.01). Despite the finding that both diseases represent a diffuse pulmonary fibrosis with a similar degree of resting ventilatory impairment, the pattern of gas exchange during exercise is different in each. These differences may be related to the underlying morphology of each process, which probably includes more airway disease and less pulmonary vascular involvement and/or a different degree of interstitial fibrotic change in asbestosis.