RESUMO
PURPOSE: To investigate inflammatory changes in the induced sputum (IS) of gas station attendants (GSAs) at risk of exposure to fuel vapors through inhalation and susceptible to respiratory complaints and impaired lung function. METHODS: Hypertonic saline-IS was collected from 52 GSAs who had never smoked (42 men, age = 35.9 ± 8.9 years) and had no known comorbidities. A group of 22 non-smokers (11 men, age = 30.5 ± 5.1 years) selected from the University staff served as control. The GSAs answered a questionnaire and underwent spirometry and chest tomography. A total of 15 inflammatory biomarkers associated with inflammation, including cytokines, chemokines, and mediators of immunological response, were also measured. RESULTS: The most common symptoms of GSAs were coughing (42.3%) and dyspnea (59.6%) based on the New York Heart Association (NYHA; Class II) classification. Significant elevations (p < 0.05) in forced vital capacity and forced expiratory volume within the first second were observed in the GSAs relative to those in the controls (GSA vs. control: 99 ± 12% vs. 90 ± 9% and 94 ± 11% vs. 87 ± 10%, respectively). The GSAs had a lower percentage of IS lymphocytes than that in the control group (4.5 ± 5.7% vs. 7.7 ± 9.8%). The GSAs also had significantly lower concentrations of IL-4, IL-5, IL-10, IL-12P70, IFN-γ, and MIP-1α, but IL-3 levels were higher. No differences were observed in the airway thickness and the amount of emphysema between the GSAs and the controls. CONCLUSION: Despite normal lung function and absence of abnormalities on HRCT, GSAs have a higher frequency of respiratory complaints, with evidence of impairment of lymphocytic activity in the airways.
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Pulmão , Escarro , Adulto , Volume Expiratório Forçado , Humanos , Masculino , Espirometria , Capacidade VitalRESUMO
OBJECTIVE: To assess clinical, functional, and inflammatory patterns of children and adolescents with severe uncontrolled asthma, and investigate the differences between patients who achieved asthma control and those who remain uncontrolled after standardized asthma care strategy. METHODS: Screening all children and adolescents with asthma from the Pediatric Pulmonology Outpatient Clinic of Unicamp, Brazil, and included those with severe uncontrolled asthma according to GINA guidelines criteria. Patients were assessed at baseline and after by demographic and medication data, questionnaires (Asthma Control Test and Pediatric Asthma Quality of Life Questionnaire), Six-Minute Walk Test, skin prick test, spirometry, induced sputum, and blood collection (total immunoglobulin E and eosinophil count). Cytokine dosage was analyzed in sputum supernatant and serum by Cytometric Bead Array. RESULTS: Thirty-three patients with severe uncontrolled asthma were included (median age 10.9 [7.00-17.60] years). All patients presented satisfactory adherence to treatment and 50% of them achieved good asthma control after six-month follow-up (p < 0.001). Patients who achieved asthma control reported higher intervals since their last exacerbation episode (p = 0.008) and higher quality of life scores (p < 0.001) as compared to patients who remained uncontrolled. We found no changes in lung function markers, inflammatory biomarkers, or cytokine levels between patients with uncontrolled and controlled asthma. CONCLUSION: Participation of six months in a structured outpatient clinic for children with severe asthma had a notable improvement in control and quality of life of patients. This demonstrates the importance of a global assessment, focused on peculiarities presented by patients with severe uncontrolled asthma.
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Asma , Qualidade de Vida , Adolescente , Asma/tratamento farmacológico , Biomarcadores , Criança , Citocinas , Humanos , Espirometria , EscarroRESUMO
Las enfermedades broncopulmonares se asocian a diversos mecanismos inflamatorios de las vías aéreas. Evaluar y comprender el perfil inflamatorio de estos pacientes podría contribuir a conocer la etiología y así optimizar el tratamiento. El esputo inducido es una técnica mínimamente invasiva, por lo que su implementación resulta de interés en la práctica habitual. Aunque el estudio del esputo inducido ha demostrado utilidad y seguridad, los centros que desarrollan esta técnica en la Argentina son escasos. Con el objetivo de estandarizar el procedimiento de recolección y análisis de muestras de esputo inducido en pacientes con enfermedades inflamatorias broncopulmonares, se desarrolló esta guía consensuada por los centros con experiencia en esta técnica en nuestro país. Es nuestra intención difundir esta técnica, mínimamente invasiva, para su aplicación en servicios especializados. Esta guía de procedimientos detalla los materiales que son requeridos, los métodos y los estándares de calidad y seguridad tanto para los pacientes como para los operadores.
Bronchopulmonary diseases are associated with different inflammatory mechanisms of the airways. Assessing and understanding the inflammatory profile of these patients could contribute to the understanding of the etiology and thus optimize the treatment. Induced sputum is a minimally invasive technique, so its implementation is of interest in the usual practice. Although the studies of induced sputum have shown usefulness and safety, the centers that develop this technique in Argentina are scarce. With the aim of standardizing the procedure that includes the collection and analysis of induced sputum samples in patients with bronchopulmonary inflammatory diseases, some centers in our country with experience in this technique achieved a consensus on the development of this Guide. It is our intention to disseminate this minimally invasive technique for its application in specialized services. This procedure guide details the necessary materials and methods and quality and safety standards for both patients and operators.
Assuntos
Escarro , Padrões de Referência , Asma , Broncopatias , ConsensoRESUMO
BACKGROUND: The phenotypes and endotypes of severe therapy-resistant asthma (STRA) have not been fully elucidated in children. The aim of the present study was to investigate inflammatory markers in the induced sputum of children with STRA and to compare them with those present in a group of children who achieved control. METHODS: A prospective cohort of children (6-18 years of age) diagnosed with severe asthma (GINA criteria) who had undergone treatment for at least 6 months was comprehensively followed for 3 months. Inhalation technique, adherence to treatment, ACT score, and main comorbidities were assessed. Induced sputum samples were collected for cytology analysis and quantitative assessment of cytokines; the participants also underwent spirometry, plethysmography, and fractional exhaled nitric oxide (FeNO) measurement. RESULTS: Forty patients were included (average age 12.8 years; 62.5% male); of these, 13 (32.5%) were classified as STRA at the end of follow-up. There were no significant differences between the STRA and control groups in demographic data, functional test results, or FeNO levels. The eosinophilic inflammatory pattern predominated in both groups; however, the STRA group showed a proportionally higher percentage of sputum neutrophils (P < 0.05). The median sputum levels of the cytokines IL-10, GM-CSF, IFN-γ, and TNF-α were significantly higher in the STRA group (P < 0.05). GM-CSF and TNF-α levels showed inverse correlations with ACT scores. CONCLUSION: The presence of neutrophils, the cytokines IL-10, and IFN-γ and, more particularly, TNF-α, and GM-CSF in the sputum may play an important role in the pathophysiological mechanism of STRA in children and adolescents. Specific antagonists for these cytokines may represent a future therapeutic strategy.
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Asma/diagnóstico , Escarro/metabolismo , Adolescente , Idade de Início , Asma/terapia , Biomarcadores , Criança , Estudos de Coortes , Resistência a Medicamentos , Eosinófilos/metabolismo , Expiração , Feminino , Seguimentos , Fator Estimulador de Colônias de Granulócitos e Macrófagos/metabolismo , Humanos , Inflamação , Interferon gama/metabolismo , Interleucina-10/metabolismo , Masculino , Neutrófilos/metabolismo , Óxido Nítrico/análise , Fenótipo , Estudos Prospectivos , Testes de Função Respiratória , Índice de Gravidade de Doença , Espirometria , Resultado do Tratamento , Fator de Necrose Tumoral alfa/metabolismoRESUMO
INTRODUCTION: Induced sputum (IS) is an alternative method of obtaining sputum, but IS smears are frequently negative. Culture is more time consuming in its results, and less useful to guide the diagnosis. Polymerase chain reaction (PCR) is the most common methodology for rapid diagnosis of tuberculosis (TB), and few studies evaluated its role in IS samples. OBJECTIVES: The objective of this study is to determine the diagnostic yield of PCR for TB compared with culture in IS samples. MATERIALS AND METHODS: Prospective study. Inpatients and outpatients of >18 years with respiratory symptoms suggestive of PTB were invited to participate. The subjects were interviewed using a standardized questionnaire, and collected IS. Three samples were obtained for AFB smear and culture. A fourth sample was obtained for PCR test. RESULTS: A total of 116 IS samples were evaluated. The sensitivity, specificity, positive predictive value and negative predictive values of PCR were 95.2%, 48.4%, 29.0% and 97.9%, respectively. The area under the receiver operating characteristic curve was .72 for the PCR test (P < .0001). CONCLUSIONS: Although the PCR specificity could be underestimated, if we consider PCR to be more sensitive than the culture method used, we believed that these PCR-positive tests mean false positives. The results of PCR should always be interpreted carefully in conjunction with clinical information.
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Reação em Cadeia da Polimerase/métodos , Escarro/microbiologia , Tuberculose Pulmonar/diagnóstico , Tuberculose Pulmonar/microbiologia , Adulto , Idoso , Brasil/epidemiologia , Comorbidade , Cultura , Reações Falso-Positivas , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mycobacterium tuberculosis/genética , Valor Preditivo dos Testes , Estudos Prospectivos , Sensibilidade e EspecificidadeRESUMO
In spite of the numerous studies on chronic obstructive pulmonary disease (COPD), the cellular and molecular basis of the disease's development remain unclear. Neutrophils and eosinophils are known to be key players in COPD. Recently, neutrophil extracellular trap cell death (NETosis), a mechanism due to decondensation and extrusion of chromatin to form extracellular traps, has been demonstrated in COPD. However, there is limited knowledge about eosinophil extracellular trap cell death (EETosis) and its role in the pathogenesis of COPD. The aim of this study was to evaluate EETosis in stable COPD. Induced sputum obtained from healthy smokers and low exacerbation risk COPD A or B group patients or high exacerbation risk COPD C or D group patients were included. Samples were examined using electron microscopy and immunofluorescence. Healthy smokers (n=10) and COPD A (n=19) group exhibited neutrophilic or paucigranulocytic phenotypes, with NETosis being absent in these patients. In contrast, COPD B (n=29), with eosinophilic or mixed phenotypes, showed EETosis and incipient NETosis. COPD C (n=18) and COPD D groups (n=13) were differentiated from low exacerbation rate-COPD group by the abundant cellular debris, with COPD C group having an eosinophilic pattern and numerous cells undergoing EETosis. A hallmark of this group was the abundant released membranes that often appeared phagocytosed by neutrophils, which coincidentally exhibited early NETosis changes. The COPD D group included patients with a neutrophilic or mixed pattern, with abundant neutrophil extracellular trap-derived material. This study is the first to demonstrate EETosis at different stages of stable COPD. The results suggest a role for eosinophils in COPD pathophysiology, especially at the beginning and during the persistence of the disease, regardless of whether the patient quit smoking, with EETosis debris probably triggering uncontrolled NETosis. The main target of these findings should be young smokers with the potential to develop COPD.
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Eosinófilos/ultraestrutura , Armadilhas Extracelulares/metabolismo , Pulmão/ultraestrutura , Neutrófilos/ultraestrutura , Doença Pulmonar Obstrutiva Crônica/patologia , Estudos de Casos e Controles , Morte Celular , Estudos Transversais , Eosinófilos/metabolismo , Feminino , Imunofluorescência , Volume Expiratório Forçado , Humanos , Pulmão/metabolismo , Pulmão/fisiopatologia , Masculino , Microscopia Confocal , Microscopia Eletrônica , Pessoa de Meia-Idade , Neutrófilos/metabolismo , Doença Pulmonar Obstrutiva Crônica/metabolismo , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Fumar/efeitos adversos , Abandono do Hábito de Fumar , Prevenção do Hábito de Fumar , Escarro/citologia , Escarro/metabolismo , Capacidade VitalRESUMO
El tabaquismo es la principal causa de la EPOC, sin embargo, factores como la edad de diagnóstico, la historia previa de asma, exacerbaciones, predisposición genética y otros influirían en el desarrollo de la enfermedad. Esto estaría relacionado con los fenotipos de pacientes con EPOC, los cuales tendrían diferentes respuestas a los corticoides inhalados (CI). Recientemente, ha sido propuesto que los eosinófilos serían potenciales biomarcadores predictores de buena respuesta a los CI. Con la hipótesis de que la presencia de eosinófilos en esputo podría constituir una estrategia para diferenciar fenotipos de pacientes con EPOC, evaluamos los perfiles celulares infamatorios en muestras de esputo inducido en pacientes con EPOC no exacerbados. Para esto, se reclutaron 20 pacientes con EPOC moderado a severo que concurren al gimnasio de rehabilitación respiratoria, los cuales fueron agrupados en eosinofílicos (n: 8, cuando presentaron más de 3% de eosinófilos en la muestra de esputo inducido) o no eosinofílicos (n: 9). Se descartaron 3 muestras por contaminación con células epiteliales. Si bien no se observaron diferencias significativas en los test de función pulmonar o de marcha de 6 minutos, los pacientes con eosinoflia presentaron ligeramente mayor reversibilidad luego del broncodilatador. Además, tuvieron mayor eosinofilia periférica, mayores valores de FeNO y mejor calidad de vida (medida por cuestionarios) que los pacientes no eosinofílicos. El esputo inducido es una técnica no invasiva, económica, que representaría una herramienta útil para conocer los diferentes fenotipos inflamatorios en pacientes con EPOC.
Smoking is the major cause of COPD; however factors such as age, previous history of asthma, exacerbations, and genetic predisposition could infuence the development of the disease. This could be related with the phenotypes of COPD patients, who would have different responses to inhaled corticosteroids (ICs). Recently, it has been suggested that eosinophils are potential biomarkers that contribute to predict good response to ICs. To test the hypothesis that the presence of eosinophils in sputum could be useful to characterize different phenotypes of COPD patients, we assessed the infammatory cell profles in induced sputum samples from not exacerbated COPD patients. 20 patients with moderate to severe COPD, attending a pulmonary rehabilitation gym, were grouped into eosinophilic (8 patients who presented more than 3% eosinophils in the induced sputum sample) or neutrophilic (9 patients who had more than 60% neutrophils). Only 3 patients were excluded due to contamination of the sputum with epithelial cells. Although there were no-signifcant differences in the pulmonary function tests or the 6-minute walk, the patients with eosinophilia showed higher responsiveness to bronchodilator therapy. Besides this group presented an increase of peripheral eosinophils, higher FeNO and better quality of life (measured by questionnaires) compared with the neutrophilic patients. Induced sputum is an economic non-invasive technique and would be a useful tool to know different infammatory phenotypes in COPD patients.
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Escarro , Corticosteroides , Doença Pulmonar Obstrutiva Crônica , EosinófilosRESUMO
OBJECTIVE: To determine if nitrites (nitric oxide metabolites) measured in induced sputum decrease and correlate with improvement of clinical asthma symptoms after treatment, we performed a prospective longitudinal study in a tertiary care hospital in Arequipa, Peru. METHODS: In 95 schoolchildren with mild and moderate persistent asthma we determined nitrites in induced sputum samples (measured using the Griess assay). Clinical parameters and exercise bronchial challenge (EBC) test were performed twice, at baseline and after 3 months of beclomethasone-dipropionate treatment (median doses: 300 mcg/day, IQR: 300-450). RESULTS: Sixty out of 95 children completed the study (median age of 9-year [IQR: 7-13]). A significant change in sputum nitrites levels between admission and the end of the study was observed (34.4 nmol/ml [IQR:18.2-58.4] and 11.2 nmol/ml [6-20.1], respectively, P = < 0.0001). Also a significant correlation between decrease of sputum nitrites levels and improvement of clinical parameters (acute exacerbations [r = 0.361, P = 0.005]; use of salbutamol [r = 0.322, P = 0.013]; emergency visits [r = 0.275, P = 0.033]; and school absence [r = 0.41, P = 0.001]) from admission to the end of the study was found. However, sputum nitrites levels did not correlated with peripherical blood eosinophils or serum IgE levels or with EBC test at any point of the study. The decrease of sputum nitrites levels after the treatment was significant in each asthma group (mild and moderate), but not between groups. CONCLUSION: This study showed that measured nitrite in induced sputum (a simple and cheap non-invasive method) is a good alternative for monitoring asthmatic treatment in schoolchildren.
Assuntos
Asma/metabolismo , Nitritos/metabolismo , Adolescente , Albuterol/uso terapêutico , Asma/tratamento farmacológico , Asma/fisiopatologia , Broncodilatadores/uso terapêutico , Criança , Progressão da Doença , Serviço Hospitalar de Emergência/estatística & dados numéricos , Eosinofilia/metabolismo , Feminino , Humanos , Imunoglobulina E/sangue , Estudos Longitudinais , Masculino , Prognóstico , Estudos Prospectivos , Licença Médica/estatística & dados numéricos , Escarro/químicaRESUMO
OBJETIVOS: Revisar o papel da avaliação clínica, da qualidade de vida, da espirometria, do teste de broncoprovocação e dos marcadores inflamatórios na avaliação da asma. FONTES DOS DADOS: Pesquisa nas bases MEDLINE e LILACS. SÍNTESE DOS DADOS: A avaliação clínica auxilia na avaliação do controle da asma e é amplamente preconizada. No entanto, os pacientes podem apresentar obstrução e inflamação das vias aéreas a despeito da normalidade clínica. A espirometria quantifica o grau de obstrução das vias aéreas e auxilia no diagnóstico, enquanto a broncoprovocação pode ser indicada na suspeita de asma com espirometria normal. Já os marcadores inflamatórios do condensado do ar exalado, do escarro induzido e do lavado broncoalveolar, além dos fragmentos da biópsia brônquica, encontram-se alterados na asma e são métodos complexos, quase sempre restritos às pesquisas. A fração exalada de óxido nítrico (FeNO) é elevada nos pacientes com asma, reprodutível e não invasiva, reduzindo-se com o tratamento. O uso da FeNO como auxiliar no ajuste de doses do corticoide inalatório tem sido estudado, mas as vantagens ainda não estão claras. CONCLUSÕES: Vários métodos são necessários para avaliar de forma acurada o controle da asma, e todos têm vantagens e limitações. A avaliação clínico-funcional é útil para o diagnóstico de asma, porém limitada para avaliar de forma precisa a intensidade do processo inflamatório nas vias aéreas. É necessário que mais estudos controlados, randomizados, com adequado poder estatístico sobre a utilidade dos marcadores inflamatórios não invasivos, especialmente a FeNO, no manejo da asma, sejam realizados para determinar sua utilidade clínica.
OBJECTIVES: To review the role of clinical assessment, quality of life assessment, spirometry, bronchial responsiveness test and inflammatory markers for asthma assessment. SOURCES: Search run on MEDLINE and LILACS. SUMMARY OF THE FINDINGS: Clinical assessment aids with assessing asthma control and is widely recommended. However, patients may have airway inflammation and obstruction despite normal clinical findings. Spirometry quantifies the degree of airway obstruction and helps with diagnosis, while the bronchial responsiveness test may be indicated for when asthma is suspected but spirometry is normal. The results of assaying the inflammatory markers in exhaled breath condensate, induced sputum, bronchoalveolar lavage and bronchial biopsy specimens are abnormal in asthma patients, but these are complex techniques almost always restricted to research. Fractional exhaled nitric oxide (FeNO) is elevated in patients with asthma, is reproducible and noninvasive and reduces with treatment. Studies have investigated using FeNO to help with adjusting inhaled corticoid dosages, but the benefits are not clear. CONCLUSIONS: A range of different methods are needed to accurately assess disease control, all with their advantages and limitations. Clinical and functional assessment is useful for diagnosing asthma, but is of limited use for precisely evaluating the intensity of the inflammatory process in the airways. More randomized and controlled studies with adequate statistical power should be carried out to investigate the true utility of noninvasive inflammatory markers, especially FeNO, for asthma management.
Assuntos
Adolescente , Criança , Humanos , Asma/diagnóstico , Testes de Provocação Brônquica , Testes Respiratórios/métodos , Inflamação/diagnóstico , Óxido Nítrico , Qualidade de Vida , EspirometriaRESUMO
OBJECTIVE: To make a narrative review of the accuracy of induced sputum for diagnosis of pulmonary disease in HIV-infected patients. Data sources: The MEDLINE, LILACS, EMBASE and the Cochrane Library were searched. reference lists, abstracts of conference proceedings and scientific meetings were hand searched. METHODS: Study selection: Fifteen articles that specifically addressed the stated purpose were selected. Data extraction: Yield of sputum induction and fiberoptic bronchoscopy with bronchoalveolar lavage were analyzed using explicit methodologic to evaluate the quality of clinical trials. RESULTS: Sputum induction demonstrated 55.5 percent sensitivity and 98.6 percent specificity to Pneumocystis pneumonia. Sensitivity of sputum induction was significantly higher with immunofluorescence than with cytochemical staining (67.1 versus 43.1 percent). Sputum induction for diagnosis of bacterial pneumonia demonstrated 60 percent sensitivity, 40 percent specificity, 80 percent positive predictive value, 20 percent negative predictive value and 56 percent accuracy. In relation to tuberculosis, sputum induction demonstrated 36 percent sensitivity, 100 percent specificity, 100 percent positive predictive value and 54.2 percent negative predictive value. CONCLUSION: Sputum induction seems to be effective and safe for diagnosis of pulmonary diseases in HIV-infected patients.
OBJETIVO: Realizar uma revisão narrativa sobre a acurácia do escarro induzido no diagnóstico da doença pulmonar nos pacientes infectados pelo HIV. Fontes de dados: pesquisamos na MEDLINE, LILACS, EMBASE e Cochrane Library. Foi realizada busca manual nas listas de referências e em resumos de anais e conferências em congressos. MÉTODOS: Seleção dos estudos: foram selecionados 15 artigos que se relacionavam ao objetivo proposto. Extração dos dados: analisamos o rendimento do escarro induzido e da broncofibroscopia com lavado broncoalveolar, empregando critérios metodológicos na avaliação da qualidade dos ensaios clínicos. RESULTADOS: O escarro induzido mostrou uma sensibilidade de 55,5 por cento e especificidade de 98,6 por cento no diagnóstico da pneumocistose; a sensibilidade do escarro induzido foi significativamente maior com a imunofluorescência do que com a coloração citoquímica (67,1 vs. 43,1 por cento). O escarro induzido para o diagnóstico de pneumonia bacteriana mostrou uma sensibilidade de 60 por cento, um especificidade de 40 por cento, um valor preditivo positivo de 80 por cento, um valor preditivo negativo de 20 por cento e uma acurácia de 56 por cento. Com relação à tuberculose, o escarro induzido mostrou uma sensibilidade de 36 por cento, uma especificidade de 100 por cento, um valor preditivo positivo de 100 por cento e um valor preditivo negativo de 54,2 por cento. CONCLUSÃO: O escarro induzido parece ser efetivo e seguro no diagnóstico das pneumopatias nos pacientes infectados pelo HIV.
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Humanos , Infecções Oportunistas Relacionadas com a AIDS/diagnóstico , Pneumopatias/diagnóstico , Manejo de Espécimes/normas , Escarro/microbiologia , Doença Aguda , Pneumopatias/classificação , Manejo de Espécimes/métodosRESUMO
Induced sputum is a useful technique for assessing airway inflammation, but its role in the diagnosis of lung disease in immunosuppressed patients needs further investigation. This study compared the use of induced sputum and BAL in the diagnosis of pneumocystosis, in HIV patients. From January 1, 2001, to December 30, 2002, HIV-positive patients older than 14 were evaluated at a hospital in Florianópolis, Santa Catarina, Brazil. Patients with respiratory symptoms for seven days or longer, with a normal or abnormal chest X-ray, and those without respiratory symptoms but with an abnormal chest X-ray, were included in the study. All patients were submitted to clinical, radiological and laboratory evaluation, after which induced sputum and bronchoscopy with bronchoalveolar lavage were carried out. The samples were subjected to the following techniques: Gram and Ziehl-Neelsen staining, quantitative culture growth for pyogenic bacteria, direct staining for fungi, culture growth for mycobacteria and fungi, and Grocott-Gomori staining for Pneumocystis jiroveci, as well as total and differential cell counts. The samples with P. jiroveci were selected, as well as the samples for which no etiologic agents were observed. Forty-five patients with a mean age of 34.6, 38 male and 40 Caucasian, comprised the subjects. Interstitial infiltrate was the most frequent radiological pattern (53.3 percent). The induced sputum sensitivity was 58.8 percent, specificity 81.8 percent, predictive positive value 90.9 percent, predictive negative value 39.1 percent and accuracy 64.4 percent, for the diagnosis of pneumocystosis, compared with BAL. Based on these data, induced sputum is a useful technique for the diagnosis of pneumocystosis in HIV patients.