Induced sputum versus bronchoalveolar lavage in the diagnosis of pneumocystis jiroveci pneumonia in human immunodeficiency virus-positive patients

Abstract

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%). The induced sputum sensitivity was 58.8%, specificity 81.8%, predictive positive value 90.9%, predictive negative value 39.1% and accuracy 64.4%, 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. Key-Words: Pneumocystosis, induced sputum, bronchoalveolar lavage. It has been estimated that 65% of HIV-infected patients have pulmonary involvement in the first clinical presentation of AIDS and that about 80% of these patients will have some pulmonary manifestation during the course of the disease [1]. Pneumocystosis, caused by Pneumocystis jiroveci, is one of the most prevalent conditions [2].Pneumocystosis may have an insidious or acute onset with dyspnea and a dry cough, accompanied by a chest X-ray with reticular or reticulonodular perihilar infiltrates. The physical examination is often normal, and about 10% of the cases present no evident radiological change [3].Since Pneumocystis can not grow in artificial culture media, the diagnosis of pneumocystosis in sputum, bronchoalveolar lavage (BAL) or pulmonary tissue needs direct examination by microscopy [4].The high rates of morbidity and mortality of pneumocystosis sufferers justify the specific treatment of infected patients [5][6][7][8].There is still controversy regarding the best approach to lung disease and immunocompromised patients [9,10].Pneumocystosis patients invariably have a greatly impaired gas exchange, which inhibits and, in most cases, contraindicates the performance of invasive diagnostic techniques like bronchoscopy. Sputum analysis is the least invasive me...

Infection and inflammation in induced sputum from preschool children with chronic airways diseases

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Establishment of a quantitative real-time PCR for the detection of Pneumocystis carinii f. sp. suis in bronchoalveolar lavage samples from pigs

“…Induced sputum has been described as a useful technique for the detection of Pneumocystis jirovecii in HIV patients. 6,17 Pneumocystis infections of immunocompromised humans can be severe. 19 The fungus concentration in the lungs is likely extremely high and, as a consequence, Pneumocystis is easily expectorated with the sputum by coughing.…”

Pneumocystis jirovecii Pneumonia in Human Immunodeficiency Virus Infection

“…A growing number of institutions can make virtually all diagnoses of PCP with sputum in adults and older children who are predisposed due to HIV/AIDS or due to other immunosuppressive disorders. 57,74,75 A meta-analysis of studies comparing the use of induced sputum to BAL samples demonstrated a 55.5% sensitivity and 98.6% specificity for PCP. The sensitivity improved to 67.1% with the use of immunofluorescence staining.…”