The initial pulmonary evaluation of the immunocompromised patient.

Practical approaches to the initial evaluation of solid organ transplant patients, BMT patients, and HIV-infected patients with pulmonary disease are summarized in Figures 2, 3, and 4. These algorithms are meant to be used as guidelines for the clinician. The clinical setting will ultimately determine the extent and speed of the evaluation. Patients who are recipients of solid organ transplants and have pulmonary symptoms may have focal or diffuse changes or may have normal chest radiographs. In all these groups, sputum is obtained by expectation. If a pathogen is found in any of the groups, it is treated. When no pathogen is found on sputum examination in patients with focal disease, empiric antibiotic therapy is given. If the patients do not improve on the empiric antibiotics, then bronchoscopy is performed. Some centers proceed directly to bronchoscopy before antibiotics are started in the hope of directing antibiotic therapy. Patients who have a normal CXR or diffuse infiltrates and no identified pathogen on examination of sputum undergo bronchoscopy, and the protocol is followed until a diagnosis is made (see Fig. 2). Patients who have received a BMT and who present with pulmonary symptoms are treated as shown in Figure 3. The CXR will reveal if the infiltrate is focal or diffuse. Those with focal infiltrates are treated with broad-spectrum antibiotics for 48 to 72 hours. If the symptoms and signs do not show some resolution, then bronchoscopy is usually performed. The effect of diffuse infiltrates in BMT patients depends to a large extent how far along in recovery from the transplant the patient is when they develop the infiltrates. During the first 30 days posttransplant, pulmonary edema commonly occurs, and the infiltrates may resolve with diuresis. If the patient is not clinically fluid overloaded or they do not respond to the diuretic therapy, then bronchoscopy with BAL is indicated. Finally, many HIV-infected patients may present with pulmonary symptoms. They may have a normal CXR or a diffuse or focal pattern (Fig. 4). All patients are subjected to sputum induction to identify a pathogen. If one is identified, it is treated. Should the patient not respond to treatment adequately or a pulmonary pathogen is not found, then bronchoscopy with BAL, protected specimen brush, or a transbronchial biopsy is attempted. The above schema is a general guideline to the initial evaluation of pulmonary disorders in the ICP. The respiratory abnormality is found in most of the cases if these algorithms are closely followed. If the patient does not improve or deteriorates further, additional diagnostic procedures such as video-assisted thorascopic lung biopsy or CT-directed transthoracic needle biopsy may be needed.