Analysis of induced sputum in the diagnosis of Pneumocystis carinii pneumonia

Sixty-two patients with possible AIDS-associated Pneumocystis carinii pneumonia (PCP) were studied to determine the diagnostic usefulness of sputum analysis and whether or not the results of sputum analysis are related to severity of disease. Induced sputum was stained with Gomori Methenamine silver and modified Wright Giemsa stains. Indicators of disease severity were: extent of chest roentgenographic infiltrate, serum lactic dehydrogenase activity, alveolar-arterial oxygen tension difference, and total blood lymphocyte count. All patients with sputum negative for Pneumocystis underwent bronchoscopy with bronchoalveolar lavage. Sputum analysis was 71% sensitive and 100% specific for the diagnosis of PCP. The negative predictive value of sputum analysis was 48%. There was no relationship between sputum results and the severity of PCP. This study led to the conclusions that sputum analysis is a sensitive, specific, rapid, and low-cost technique for the diagnosis of PCP, and that the sensitivity of sputum analysis for the detection of PCP is not affected by the severity of PCP.     

Analysis of induced sputum for the diagnosis of recurrent Pneumocystis carinii pneumonia.

We studied the sensitivity of ISA for diagnosis of second-episode PCP in AIDS patients. We induced sputum in 218 patients who had known or suspected AIDS and who had a presentation suggestive of PCP. All patients with negative sputum smear for PCP underwent BAL. Twenty-five patients were identified who had second-episode PCP at least 30 days after initial diagnosis. Chest roentgenographic infiltrate patterns for these 25 patients were blindly scored as normal, diffuse, upper lobe or focal non-upper lobe. The sensitivity of ISA was 72 percent for the first episode of PCP, 72 percent for the second episode of PCP, 72 percent for patients with second-episode PCP who had initial PCP detected by ISA and 71 percent for patients with second-episode PCP whose first episode of PCP was missed by ISA. Of the ten patients who were treated with AP, only one had a false-negative sputum analysis. A comparison of patients who had second-episode PCP diagnosed by ISA with those who had false-negative sputum analysis showed no difference in time to relapse, chest x-ray film pattern (all diffuse) or use of AP.     

Rapid noninvasive diagnosis of Pneumocystis carinii from induced liquefied sputum

Pneumocystis carinii organisms cluster in alveolar casts. A method for concentrating alveolar casts in sputum specimens might improve the diagnostic usefulness of sputum studies in possible cases of pulmonary infection with Pneumocystis carinii. The use of sputum induction to detect Pneumocystis carinii was studied in 40 consecutive patients with known or suspected human immunodeficiency virus infection having bronchoscopy for evaluation of pulmonary disease. Sputum produced by deep coughing induced by 3% saline via a jet nebulizer was liquefied with dithiothreitol, and cells were sedimented and stained. Liquefaction of mucus allowed concentration of alveolar casts where P. carinii cysts were readily identified. A total of 28 patients were found to have P. carinii, which was detected in concentrated sputum in 21 of 38 patients, unconcentrated sputum in 10 of 38 patients, and by bronchoscopy in 25 of 37 patients. Sensitivity of concentrated sputum compared with bronchoscopy was 78% (95% CI, 58 to 90), with a negative predictive value of 71% (95% CI, 47 to 87). Values for unconcentrated sputum were 43% (95% CI, 25 to 63) and 48% (95% CI, 30 to 67), respectively. Liquefaction of adequately induced sputum facilitates processing and interpretation and increases yield for P. carinii, eliminating the need for invasive procedures in most patients.     

Pneumocystis carinii pneumonia: diagnosis

Pneumocystis carinii pneumonia occurs at some point in the course of illness in approximately 85% of patients with AIDS. Because of the frequency of P. carinii pneumonia and because it is readily treatable, prompt, accurate, and efficient diagnostic schemes are extremely important. The clinical presentation is generally characterized by fever, nonproductive cough, and shortness of breath. Such symptoms in a patient from a recognized HIV transmission category should prompt a diagnostic evaluation to identify P. carinii or other opportunistic infections. A chest radiograph usually provides an objective indication of lung disease. Pulmonary function tests, particularly the DLCO and lung imaging using 67Ga-labeled citrate, are useful screening tests in patients with normal chest radiographs. Examination of sputum induced by inhalation of aerosolized hypertonic saline is a very useful means of identifying P. carinii. Bronchoalveolar lavage is nearly 100% sensitive to the presence of P. carinii and should be performed in patients who have a nondiagnostic sputum examination. Transbronchial biopsy increases the overall yield for diagnoses other than P. carinii and should be performed in patients in whom bronchoalveolar lavage does not provide a diagnosis. Because of the effectiveness of sputum examinations and bronchoscopic procedures, open lung biopsy is rarely necessary.     

Effect of aerosolized pentamidine prophylaxis on the diagnosis of Pneumocystis carinii pneumonia by induced sputum examination in patients infected with the human immunodeficiency virus

This study assessed the effect of aerosolized pentamidine prophylaxis on the clinical presentation and diagnostic sensitivity of induced sputum examination for Pneumocystis carinii pneumonia. Between January 1, 1988 and October 27, 1990, 348 induced sputum examinations were performed as the initial diagnostic procedure for P. carinii pneumonia in patients infected with the human immunodeficiency virus (HIV). Medical records were reviewed for all induced sputum examinations, and the study group consisted of patients who either had not received prophylactic therapy (n = 193) or had received aerosolized pentamidine prophylaxis (n = 126). A total of 29 induced sputum examinations in patients receiving either other prophylactic regimens or ongoing therapy for previously documented P. carinii pneumonia were excluded from the study group. A total of 72 consecutive episodes of P. carinii pneumonia were subsequently documented by induced sputum examination (n = 54), bronchoalveolar lavage (n = 16), thoracocentesis (n = 1), or autopsy (n = 1). A total of 44 episodes occurred in patients who had not received antipneumocystis prophylaxis, and 28 episodes occurred in patients who had received aerosolized pentamidine. Of patients capable of producing a sputum specimen for analysis, induced sputum examination had a significantly lower diagnostic yield of 64.3% in patients who had received aerosolized pentamidine prophylaxis compared with 92.3% in patients who did not receive prophylaxis (p less than 0.02, Fisher's exact test). When the data were analyzed on an intention to treat basis, although there was a trend suggesting a lower overall yield in the aerosolized pentamidine patients, the difference was not statistically significant (64.3 versus 81.8%, p = 0.17, Fisher's exact test).(ABSTRACT TRUNCATED AT 250 WORDS)     

The usefulness of induced sputum in the diagnosis of Pneumocystis carinii pneumonia in patients with the acquired immunodeficiency syndrome

Thirty-two patients with or suspected of having the acquired immunodeficiency syndrome were evaluated for opportunistic lung infection using examination of sputum induced by inhalation of 3% saline. The specimens obtained were stained with Giemsa stain and examined for Pneumocystis carinii. Smears of sputum were also appropriately stained and examined for acid-fast organisms and fungi, as well as cultured for these organisms. Patients whose sputum did not contain P. carinii had bronchoscopy within 24 h of sputum induction. Twenty-five of the 32 patients were ultimately determined to have P. carinii pneumonia. Of these, 14 were detected by examination of sputum (sensitivity, 56%). Of 18 patients whose sputum did not contain P. carinii, 11 had the organism detected in specimens obtained by bronchoscopy (negative predictive value, 39%). There were no clinical features that identified patients more likely to have a positive sputum examination. No additional treatable lung pathogens appeared to be missed by sputum examination. In this select population, examination of induced sputum establishes the diagnosis of P. carinii pneumonia in a significant proportion of patients, thereby decreasing the need for more invasive procedures.     

Pneumocystis carinii pneumonia complicating multiple myeloma

Pneumocystis carinii pneumonia complicated the course of two patients with multiple myeloma. The diagnosis was established in both cases by bronchoalveolar lavage, which demonstrated the typical pneumocysts. Clinical and roentgenographic improvement in both patients was observed following a course of trimethoprim-sulfamethoxazole. One patient had lymphocyte subsets performed with a CD4/CD8 ratio of 0.8; both patients were HIV antibody-negative by ELISA. Both patients tolerated prophylactic TMP-SMX given concurrently with the subsequent chemotherapy for myeloma. We suggest that the immune defect seen in multiple myeloma may have placed these patients at risk for opportunistic infections such as P carinii pneumonia; however, as opposed to patients with AIDS, our patients tolerated therapy with TMP-SMZ quite well.     

Sputum examination for the diagnosis of Pneumocystis carinii pneumonia in the acquired immunodeficiency syndrome

The diagnostic utility of sputum examination in patients with Pneumocystis carinii pneumonia secondary to the acquired immunodeficiency syndrome (AIDS) has so far not been determined. Sputum was induced in 43 patients with AIDS or suspected AIDS just prior to fiberoptic bronchoscopy, scheduled because of an unexplained pulmonary infiltrate on a chest radiograph. Pneumocystis carinii pneumonia was diagnosed by sputum examination and/or by a bronchoscopic procedure in 20 patients. Of these, sputum samples were positive for Pneumocystis organisms in 11 (55%) of 20 patients tested, bronchial washings were positive in 11 (79%) of 14 patients tested, brush biopsies were positive in 9 (53%) of 17 patients tested, and transbronchial lung biopsies were positive in 18 (90%) of 20 patients tested. The presence of P. carinii cysts in sputum did not correlate with the presence of alveolar macrophages in sputum nor with the volume of sputum. Sputum examination for P. carinii organisms, employed as a first diagnostic step in patients with AIDS with pulmonary infiltrates, may frequently obviate the need for bronchoscopy.     

S-adenosylmethionine concentrations in diagnosis of Pneumocystis carinii pneumonia

Pneumocystis carinii is unable to synthesise S-adenosylmethionine and thus scavenges this intermediate. We aimed to test whether measurement of concentrations of this metabolic intermediate in plasma could provide a new method for rapid diagnosis of Pneumocystis carinii pneumonia (PCP). We measured S-adenosylmethionine plasma concentrations in 12 healthy controls, 16 patients with confirmed or suspected PCP, and 36 patients with other infections. Median concentration in healthy controls was 106 nmol/L (range 86-128), but the protein was undetectable in eight patients with histologically proven and seven with suspected PCP, and was 8 nmol/L in another confirmed case (p<0.0001). In 36 patients with other infections, S-adenosylmethionine concentrations were much the same as in controls: 18 had bacterial pneumonia, two tuberculosis, five cryptococcal meningitis, three had other infections, and eight had asymptomatic HIV-1 infection. After treatment for PCP, S-adenosylmethionine concentrations rose rapidly in all but one patient who died of the disease. Measurement of plasma S-adenosylmethionine concentrations could prove useful for diagnosis of PCP and assessment of patients' response to treatment.     

Pneumocystis carinii pneumonia

Pneumocystis carinii pneumonia (PCP) is the most common index diagnosis in patients with acquired immunodeficiency syndrome (AIDS). Eighty percent of AIDS patients will eventually develop PCP. Common presenting symptoms are shortness of breath, cough, weight loss, and fever. The chest radiograph typically reveals a diffuse, bilateral, symmetric, fine-to-medium reticulonodular pattern of opacities. Upper lobe disease has been reported recently in patients who have undergone prophylactic therapy with aerosolized pentamidine. Pneumatoceles, or thin-walled air-containing cysts, have been noted in 10% of patients with PCP. Lymphadenopathy and pleural effusion are extremely rare. Therapy with various agents is generally successful, resulting in clinical and radiographic improvement within 7 to 10 days. Recurrence of PCP is common.     

Pneumocystis carinii pneumonia

Throughout the epidemic, Pneumocystis carinii pneumonia (PCP) has been the most common AIDS-defining opportunistic infection in the United States. With the widespread use of highly active antiretroviral therapy (HAART) and prophylaxis in patients known to be at risk, the incidence of PCP in patients with AIDS has declined dramatically. However, it is still seen regularly in patients with previously undiagnosed human immunodeficiency virus (HIV) infection, those who do not comply with prophylactic medications, and in occasional cases of failure of prophylaxis. Despite many years of study, our understanding of the biology, ecology, and pathogenesis of PCP is inadequate. Clinically, PCP in AIDS tends to be a less acute and milder illness than PCP in other types of immunocompromised hosts. Although the radiograph typically shows bilateral diffuse granular opacities, many other patterns are seen. Trimethoprim-sulfamethoxazole is the preferred drug for treating and preventing PCP, but toxicity limits its use. The choice of treatment is influenced by the severity of illness and relative toxicities of antipneumocystis agents. Adjunctive corticosteroid therapy is recommended for patients with moderate or severe disease. The success of HAART has prompted investigators to question whether prophylaxis against PCP and other opportunistic infections is necessary in patients who respond with a rise in CD4 lymphocyte counts and suppression of HIV replication.