The role of exercise testing in pulmonary diagnosis

Exercise stresses the body's functional reserves that allow for the increased metabolic work and gas transport necessary for the efficient production of energy with physical activity or stress. Disease that reduces reserve in the gas transport organs will produce exertional symptoms not present at rest. Exercise testing has been well established in the evaluation of healthy persons and cardiac patients who are limited by cardiac or peripheral muscle function. For patients with lung disease, however, whose exercise performance is limited by reduced ventilatory capacity and disordered gas exchange, principles of exercise testing (and training) are different. In the evaluation of pulmonary patients, exercise testing can be used to measure exercise tolerance, assess the limitation to exercise in patients with unexplained dyspnea, evaluate patients for respiratory disability, assess blood gas changes with exercise, and detect exercise-induced asthma. Nevertheless, our understanding of the role of exercise in pulmonary diagnosis is at an early stage of development and much needs to be learned about the practical applications of exercise testing in the diagnosis, staging, and serial evaluation of pulmonary diseases.     

The role of induced sputum in the diagnosis of pulmonary tuberculosis

OBJECTIVES: To determine the sensitivity of referral guidelines for induced sputum in pulmonary tuberculosis (PTB) case detection and determine the diagnostic yield of the test. METHODS: A retrospective analysis of case notes of adult patients referred for induced sputum was carried out at the North Trent Regional Department of Infection and Tropical Medicine, the Royal Hallamshire Hospital, Sheffield, UK. Clinical characteristics were noted on patients referred during a 12-month period in 2001-2002, and of all patients with positive induced sputum results from April 1998 to March 2002. RESULTS: Over a 12-month period 114 patients were referred in our unit for induced sputum sampling. Twelve of the 114 patients had positive sputum cultures giving a positive yield for the test of 10.5%. With strict adherence to our referral guidelines, 10 of the 12 positive cases (83.3%) would have been detected. With modification to the referral guidelines, all 12 microbiologically positive cases would have been detected making the guidelines 100% sensitive in detecting microbiologically positive cases among patients referred with a clinical suspicion of PTB who are unable to self-expectorate. The positive yield for the test would have been increased to 13.2%. In the past 4 years 29 patients had positive induced sputum results. Of these, 11 patients (37.9%) had concurrent microbiological proven extra-pulmonary TB (EPTB) and 10 (34.5%) had past histories of TB infection. Seven patients had chest X-rays reported as normal. CONCLUSIONS: Induced sputum offers a relatively non-invasive investigation for patients with suspected PTB who are unable to bring up sputum. Induced sputum also offers a means of establishing a microbiological diagnosis in some cases of EPTB. An investigative algorithm is suggested.Summary. In an era of increasing drug resistant disease, establishing a microbiological diagnosis of TB is paramount. Sputum induction can be used as an alternative investigation to bronchoscopy in suspected PTB patients who are able to self-expectorate. Induced sputum is a sensitive investigation for suspected PTB patients but with a low diagnostic yield. Referral guidelines are suggested.     

Molecular polymerase chain reaction diagnosis of pulmonary mucormycosis caused by Cunninghamella bertholletiae

OBJECTIVE: Mucormycosis is an uncommon but frequently fatal infection caused by strains of mucorales in immunocompromised hosts. In this study, we report a case of pulmonary mucormycosis associated with acute lymphocytic leukaemia caused by Cunninghamella bertholletiae, a rare pathogen. METHODOLOGY: Retrospective analysis of the stored serum, sputum, and necropsy lung tissue samples from this patient, enabled subspecies identification by means of panfungal polymerase chain reaction (PCR), direct DNA sequencing of the PCR products, and homology search with nucleotide basic local alignment search tool. RESULTS: The development of a reliable diagnostic blood test for angio-invasive fungal infections such as mucormycosis is desirable, because the sensitivity of culture for these fungi is extremely low. CONCLUSION: Panfungal PCR on serial serum samples might be useful for the diagnosis of pulmonary mucormycosis.     

Clinical spectrum of pulmonary mucormycosis

Pulmonary mucormycosis is an uncommon, but important, opportunistic fungal pneumonia which is often diagnosed post-mortem. This review emphasizes clinical and pathologic characteristics of pulmonary mucormycosis that differentiate this infection from other fungal pneumonias. The most common clinical presentation of pulmonary mucormycosis is a rapidly progressive pneumonia with diffuse infiltrates on chest radiographic examination of a patient with an underlying hematologic malignancy treated with immunosuppressive drugs. Other immunocompromised hosts at risk for pulmonary mucormycosis include patients with diabetes mellitus who may develop a distinctive endobronchial form of this disease. Early consideration of this diagnosis, along with aggressive diagnostic evaluation, are critical to effective therapy and patient survival. While treatment with amphotericin B is the mainstay of therapy for pulmonary mucormycosis, diabetics with endobronchial disease may benefit from early, aggressive surgical resection of the involved lung tissue.     

The role of spiral computerized tomography in the diagnosis of pulmonary embolism

The diagnostic strategy of pulmonary embolism has changed in the last few years with the use of the pulmonary spiral angio-scan. It has become the investigation of first intention for the positive diagnosis of pulmonary embolism. Its limitations are known, essentially the difficulties in visualisation of distal pulmonary embolism. However, the introduction of new 64-slice scanners has considerably improved the resolution. The indications of the spiral angioscanner have recently increased with the study of pulmonary artery vascularisation and the calculation of Qanadli's obstruction index, the study of the peripheral venous system and the evaluation of right ventricular dysfunction by the calculation of the ratio of surfaces (or diameters) of RV/LV.     

The role of spiral volumetric computed tomography in the diagnosis of pulmonary embolism

To evaluate the evidence for the use of spiral volumetric computed tomography (SVCT) in the diagnosis of acute pulmonary embolism (PE), the 11 English-language studies published through July 1998 that compared SVCT with a reference standard for PE were systematically reviewed. Among the reviewed studies, methodological problems were common. Only 5 of these studies fulfilled 5 of 11 basic standards addressing important issues in diagnostic test research. The reported sensitivities of SVCT compared with pulmonary angiography varied widely (64%-93%), which was likely the result of differences in study populations. Spiral volumetric computed tomography may be relatively sensitive and specific for diagnosing central pulmonary artery PEs, but it is insensitive for diagnosing subsegmental clots. Spiral volumetric computed tomography may have a role as a "rule-in" test for large central emboli, but additional research is required to establish its place in clinical practice.     

The role of newer diagnostic techniques in the diagnosis of pulmonary embolism.

Among the evolving techniques for the diagnosis of acute pulmonary embolism, contrast enhanced spiral CT takes a particularly prominent role because it is available at most centers, it images the pulmonary embolism directly, and it is minimally invasive. It has not yet been fully evaluated, however. Magnetic resonance angiography also has appeal for similar reasons. Few patients have been studied, however. Magnetic resonance angiography for pulmonary embolism is still in the early testing phase. Transesophageal echocardiography can image pulmonary embolism in central pulmonary arteries, but preliminary tests suggest that it has a low negative predictive value and cannot be used to exclude pulmonary embolism. Finally, it seems that a rapid and sensitive technique for measuring d-dimer may now be available, which may assist in eliminating the diagnosis of acute pulmonary embolism in a significant percentage of patients in whom the diagnosis is suspected.     

Inflammatory cytokines in BAL fluid and pulmonary hemodynamics in high-altitude pulmonary edema

To evaluate the pathogenesis of high-altitude pulmonary edema (HAPE), we performed bronchoalveolar lavage (BAL) and pulmonary hemodynamic studies in seven patients with HAPE at its early stage. We measured cell counts, biochemical contents, and concentrations of pro-inflammatory cytokines including interleukin (IL)-1, IL-6, IL-8 and tumor necrosis factor (TNF)-α and of anti-inflammatory cytokines including IL-1 receptor antagonist (ra) and IL-10 in the BAL fluid (BALF). All patients showed increased counts for total cells, alveolar macrophages, neutrophils and lymphocytes, and markedly elevated concentrations of proteins, lactate dehydrogenase, IL-1β, IL-6, IL-8, TNF-α and IL-1ra. The levels of IL-1α and IL-10 were not increased. Patients also showed pulmonary hypertension with normal wedge pressure. Both the driving pressure obtained as pulmonary arterial pressure minus wedge pressure and the Pa_O2 under room air were significantly correlated with the concentrations of IL-6 and TNF-α in the BALF. These findings suggest that the inflammatory cytokines play a role at the early stage of HAPE and might be related to pulmonary hypertension.     

Bilateral pulmonary mucormycosis with diabetic ketoacidosis

A 38 year-old woman admitted for bilateral infiltrates with a cavity and treated diabetic ketoacidosis and elevated inflammatory reaction in clinical examination was found in transbronchial lung biopsy specimens to have bilateral pulmonary mucormycosis. We controlled blood glucose with insulin and removed bilateral pulmonary lesions separately. Pulmonary mucormycosis with diabetic ketoacidosis is a rare but fatal fungal infection. Early diagnosis, intensive insulin therapy, and surgical resection may save patients with pulmonary mucormycosis even if lesions are bilateral.     

The diagnosis of pulmonary embolism: the role of noninvasive technics]

Today a large group of patients with pulmonary embolism is still undetected because this disease is not suspected. We evaluated the role of routine clinical procedures such as history, chest x-ray, electrocardiogram and blood gas analysis in the diagnosis of this disease. We studied 177 patients sent to our observation with suspicion of pulmonary embolism, which was later confirmed in 97 and excluded in 80. Prolonged immobilization, surgical procedures and deep vein thrombosis are the most frequent predisposing factors (P less than 0.05 or less) in patients with pulmonary embolism with respect to patients with unconfirmed suspicion of embolism. Among symptoms and signs, pleuritic chest pain, sudden onset of dyspnea, tachypnea, fever, enlarged jugular veins, enhanced pulmonary component of the second heart sound, pulmonary systolic murmur and basal hypophonesis were the most frequent signs (P less than 0.005 or less) in patients with embolism. Among radiographic signs "sausage" descending pulmonary artery, diaphragmatic elevation, pulmonary infarction, Westermark sign and azygos vein enlargement were more frequent (P less than 0.05 or less) in patients with embolism with respect to patients with unconfirmed suspicion of embolism. Among electrocardiographic signs, tachycardia, P-R segment displacement and negative T wave in V1-V2 were more frequent in patients with embolism with respect to patients with unconfirmed suspicion of embolism (P less than 0.05 or less). PO2, standard pO2 and pCO2 were significantly lower (P less than 0.001) in patients with embolism. After discriminant analysis of the whole data set most patients were correctly classified as embolic (90/97) and non-embolic (75/80).(ABSTRACT TRUNCATED AT 250 WORDS)     

Bronchoscopic diagnosis of pulmonary infiltrates in granulocytopenic patients with hematologic malignancies: BAL versus PSB and PBAL

BACKGROUND: Treatment of patients with hematologic malignancies is often complicated by severe respiratory infections. Bronchoscopy is generally to be used as a diagnostic tool in order to find a causative pathogen. OBJECTIVES: In a prospective study the combination of protected specimen brush (PSB) and protected bronchoalveolar lavage (PBAL) was compared with bronchoalveolar lavage (BAL) for evaluated feasibility and diagnostic yield in granulocytopenic patients with hematologic malignancies and pulmonary infiltrates. METHODS: All specimens from 63 bronchoscopic procedures (35 BAL and 28 PSB-PBAL) were investigated by cytological examination and various microbiological tests. If clinically relevant and feasible, based on the clinical condition and/or the presence of thrombocytopenia, lung tissue samples were obtained. RESULTS: The majority of the 58 included patients were diagnosed as having acute myeloid leukaemia and developed a severe neutropenia (BAL-group: 27 days; PSB-PBAL group: 30 days). Microbiological and cytological examination of 63 bronchoscopic procedures (35 BAL and 28 PSB-PBAL) yielded causative pathogens in 9 (26%) patients of the BAL-group and 8 (29%) patients of the PSB-PBAL group (PSB and PBAL 4 each). Aspergillus fumigatus was the pathogen most frequently (13%) detected. Using all available examinations including the results of autopsy, a presumptive diagnosis was established in 43% of the patients in the BAL group and 57% of those in the PSB-PBAL group; in these cases microbial aetiology was correctly identified in 67% and 57%, respectively. The complication rate was of these procedures were low, and none of the patients experienced serious complications due to the invasive techniques. CONCLUSIONS: Our results showed that modern bronchoscopic techniques such as PSB and PBAL did not yield better diagnostic results compared to BAL in granulocytopenic patients with hematologic malignancies and pulmonary infiltrates. In approximately half of the cases a presumptive diagnosis was made by bronchoscopic procedures.     

Invasive pulmonary mucormycosis with rupture of the thoracic aorta

We report an acute myelogenous leukemia patient with mucormycosis who died of massive hemoptysis during antifungal therapy. The diagnosis was made postmortem and autopsy revealed that the pulmonary nodule consisting of mucorales protruded over the luminal surface of the aorta. Microscopic examination showed the invasion of mucor hyphae into the wall of the aortic arch. Surgical treatment may be indicated for patients with pulmonary mucormycosis refractory to amphotericin B therapy. Am. J. Hematol. 58:326–329, 1998. © 1998 Wiley-Liss, Inc.     

The role of bronchoscopy in the diagnosis and treatment of pulmonary disease in HIV-infected patients

Background: Pulmonary disease is the most common reason for presentation and the major cause of death in HIV-infected patients. There has been an evolution in the optimal approach to the investigation of a pulmonary infiltrate in HIV-infected patients since the introduction of induced sputum for the diagnosis of Pneumocystis carinii pneumonia (PCP). Aims: To evaluate the usefulness of flexible fibreoptic bronchoscopy (FFB), bronchoalveolar lavage (BAL), transbronchial biopsy (TBB) and bronchial brushings (BB) in the diagnosis of pulmonary disease in HIV-infected patients and to examine the effect of FFB on changes in therapy and survival. Methods: The histories of all HIV-infected patients referred to Fairfield Hospital for FFB between January 1990 and June 1993 were examined retrospectively. Results: Forty-two FFB were performed on 41 patients (40 male and one female). Definitive diagnoses made at FFB included Kaposi's sarcoma (KS) (n= 9), invasive aspergillosis (n= 5), PCP (n= 4), Mycobacterium avium complex (MAC) pneumonia (n= 2), cytomegalovirus (CMV) pneumonia (n= 1), Cryptococcus neoformans pneumonia (n= 1), microsporidium (n= 1) and Pseudomonas aeruginosa pneumonia (n= 1). TBB and BB did not provide a diagnosis for diseases not seen macro-scopically at FFB or diagnosed by BAL. FFB findings altered diagnosis in 21/42 (50%) presentations and changed therapy in 26/42 (62%) cases. Conclusions: FFB together with BAL altered the working diagnosis and changed therapy in a significant number of patients. TBB and BB should not be routinely performed in all patients as these procedures are of limited value in this setting.