Fiberoptic bronchoscopy for diagnosis of opportunistic pulmonary infections after bone marrow transplantation

Bronchoalveolar lavage and lung biopsy in patients with cancer and hematopoietic stem-cell transplantation recipients: a systematic review and meta-analysis

PURPOSE

The objective of this study was to describe the diagnostic yield and complication rate of bronchoalveolar lavage (BAL) and lung biopsy in the evaluation of pulmonary lesions in patients with cancer and recipients of hematopoietic stem-cell transplantation (HSCT).

METHODS

We conducted a systematic literature review and performed electronic searches of Ovid MEDLINE, EMBASE, and Cochrane Central Register of Controlled Trials. Studies were included if patients had cancer or were recipients of HSCT, and if they underwent BAL or lung biopsy for the evaluation of pulmonary lesions. Only English language publications were included.

RESULTS

In all, 14,148 studies were screened; 72 studies of BAL and 31 of lung biopsy were included. The proportion of procedures leading to any diagnosis was similar by procedure type (0.53 v 0.54; P = .94) but an infectious diagnosis was more common with BAL compared with lung biopsy (0.49 v 0.34; P < .001). Lung biopsy more commonly led to a noninfectious diagnosis (0.43 v 0.07; P < .001) and was more likely to change how the patient was managed (0.48 v 0.31; P = .002) compared with BAL. However, complications were more common with lung biopsy (0.15 v 0.08; P = .006), and procedure-related mortality was four-fold higher for lung biopsy (0.0078) compared with BAL (0.0018).

CONCLUSION

BAL may be the preferred diagnostic modality for the evaluation of potentially infectious pulmonary lesions because of lower complication and mortality rates; thus, choice of procedure depends on clinical suspicion of infection. Guidelines to promote consistency in the approach to the evaluation of lung infiltrates may improve clinical care of patients.

Minimally Invasive Diagnostic Strategy in Immunocompromised Patients with Pulmonary Infiltrates

Acute respiratory failure (ARF) is the main reason for ICU admission in patients with haematological malignancies. High mortality rates of up to 50% are reported in this situation, and mortality is highest when mechanical ventilation is needed. Rapid and accurate diagnostic methods are needed in these vulnerable patients to ensure the prompt initiation of effective treatment. However, the broad array of possible cause of ARF raises diagnostic challenges. In this review, we discuss the DIRECT strategy, which identifies the most plausible diagnosis in each patient based on the type of immune deficiency and clinical presentation. We will focus on non-invasive laboratory tests developed in recent years, discussing their sensitivity and specificity. We also discuss the usefulness in cancer patients with specific organ dysfunctions of biomarkers introduced over the past few years.

The clinical importance of bronchoalveolar lavage in allogeneic SCT patients with pneumonia

Patients who undergo allogeneic hematopoietic SCT (HSCT) are prone to pulmonary infections. Between 1998 and 2004, a total of 450 patients underwent HSCT at Karolinska University Hospital, Huddinge. Pneumonia was diagnosed in 167 patients (37%), including 42 children. Bronchoalveolar lavage (BAL) was performed on 68 occasions in 57 patients (six children). In 110 patients (36 children) with pneumonia, BAL was not performed. BAL contributed to the diagnosis in 43 cases (63%) and to relevant findings in 53 cases: bacteria (n=13, 24%), viruses (n=28, 53%) and fungi (n=12, 23%). In 25 cases BAL was negative. In 15 of these cases, BAL was performed >or=4 days after chest X-ray, and in four cases not in the same segment as the infiltrations. The median time between radiographic findings and positive BAL was 2 (0-15) days, and a negative BAL 6 (1-30) days (P<0.001). Antimicrobial treatment was administered to 79% patients with positive findings, and to 92% with negative findings at the time of BAL. No serious complications due to the procedure were reported. BAL resulted in a changed treatment in 32/68 (47%) episodes of pneumonia. To conclude, BAL is a safe and useful diagnostic procedure that should be performed early after the onset of pneumonia following allogeneic HSCT.

Evaluation of pulmonary infiltrates in patients after stem cell transplantation

Hematopoietic stem cell transplantation is potentially curative therapy that has become the standard of care for many hematologic malignancies. Pulmonary complications occur in about 50% of stem cell transplant recipients and no other organ dysfunction has a higher mortality. Unfortunately the diagnosis of these infiltrates is hampered by the poor yield from routine studies and this patient population is rarely able to tolerate more risky procedures that will obtain tissue for microscopy and culture. A bronchoalveolar lavage (BAL) is usually insufficient to make a diagnosis of invasive fungal, significant bacterial, or pathogenic viral infections in patients that will still benefit from a change in therapy. In this review we discuss the infectious etiologies of pulmonary infiltrates post hematopoietic stem cell transplant, the non-infectious causes of infiltrates such as diffuse alveolar hemorrhage, engraftment syndrome, and idiopathic pneumonia syndrome, and the yield of newer diagnostic procedures ranging from peripheral blood galactomannan to cytomegalovirus antigenemia, and report on new technologies that promise more accurate and timely diagnoses of these infiltrates.

Diagnostic strategy in cancer patients with acute respiratory failure

OBJECTIVE

Nearly 15% of cancer patients experience acute respiratory failure (ARF) requiring admission to the intensive care unit, where their mortality is about 50%. This review focuses on ARF in cancer patients. The most recent literature is reviewed, and emphasis is placed on current controversies, most notably the risk/benefit ratio of fiberoptic bronchoscopy and BAL in patients with severe hypoxemia.

BACKGROUND

Fiberoptic bronchoscopy with bronchoalveolar lavage (BAL) is the cornerstone of the causal diagnosis. However, the low diagnostic yield of about 50%, related to the widespread use of broad-spectrum antimicrobial therapy in cancer patients, has generated interest in high-resolution computed tomography (HRCT) and primary surgical lung biopsy. In patients with hypoxemia, bronchoscopy and BAL may trigger a need for invasive mechanical ventilation, thus considerably decreasing the chances of survival.

DISCUSSION

The place for recently developed, effective, noninvasive diagnostic tools (tests on sputum, blood, urine, and nasopharyngeal aspirates) needs to be determined. The prognosis is not markedly influenced by cancer characteristics; it is determined chiefly by the cause of ARF, need for mechanical ventilation, and presence of other organ failures. Although noninvasive ventilation reduces the need for endotracheal intubation and diminishes mortality rate, its prolonged use in patients with severe disease may preclude optimal diagnostic and therapeutic management. The appropriateness of switching to endotracheal mechanical ventilation in patients who fail noninvasive ventilation warrants evaluation.

CONCLUSION

This review discusses risks and benefits from invasive and non invasive diagnostic and therapeutic strategies in critically ill cancer patients with acute respiratory failure. Avenues for research are also suggested in order to improve survival in these very high risk patients.

Radiologically guided fine needle lung biopsies in the evaluation of focal pulmonary lesions in allogeneic stem cell transplant recipients

Lung problems are common in allogeneic stem cell transplant (SCT) recipients. To evaluate the feasibility and diagnostic yield of radiologically guided fine needle lung biopsy (FNLB) in allogeneic SCT recipients with focal pulmonary lesions, a retrospective analysis was carried out. Between 1989 and 1998, radiologists performed a total of 30 FNLBs in 21 allogeneic SCT recipients, guided either by ultrasound (n = 17) or computed tomography (n = 13). The median time from SCT to the first FNLB was 131 days (20-343 days). Prophylactic platelet transfusions were given in 19 procedures (66%). The complications of FNLB included clinically insignificant pneumothorax in four procedures (13%) and self-limiting haemoptysis in one case (3%). The first FNLB was suggestive of invasive pulmonary aspergillosis (IPA) in five patients (24%). Additional clinically useful findings of FNLB included Pseudomonas (two patients) and Nocardia (one patient). The final diagnosis of pulmonary lesions was IPA in 14 patients, immunological lung problems in four patients and other in three patients. Radiologically guided FNLB is feasible in allogeneic SCT recipients and has a low complication rate. The diagnostic yield is high especially for IPA.

Bronchoalveolar lavage in the diagnosis of pulmonary complications of bone marrow transplant patients

Bronchoalveolar lavage (BAL) has proved valuable in the diagnosis of pulmonary complications in immunosuppressed patients. We evaluated the diagnostic yield of BAL in pulmonary complications in bone marrow transplantation (BMT) recipients. We reviewed sequentially the records of 89 patients during an 18-month period. BAL was diagnostic in 42 patients (47%). The most common pulmonary complication diagnosed by BAL was diffuse alveolar hemorrhage (n = 15); followed by bacterial pneumonia (n = 10), respiratory syncytial virus (n = 8), aspergillosis (n = 6), Pneumocystis carinii pneumonia (n = 5), cytomegalovirus (CMV) (n = 4), and others (n = 4). The final diagnoses in the BAL non-diagnostic group were: bacterial pneumonia (n = 6), CMV (n = 6), idiopathic pneumonia syndrome (n = 5), cancer recurrence (n = 4), cardiogenic pulmonary edema (n = 4), and others (n = 9). We conclude that BAL is a useful diagnostic tool in BMT-related pulmonary complications.

Diagnostic aspects of invasive Aspergillus infections in allogeneic BMT recipients

To investigate diagnostic aspects of invasive aspergillosis (IA) in allogeneic BMT recipients, the charts of 22 consecutive patients with IA transplanted in 1989-1995 were reviewed. IA was diagnosed 69-466 days (median 131 days) post BMT. In 16 patients (73%), a definite or probable diagnosis of IA was made during life. Respiratory symptoms were the presenting feature in half of the patients followed by neurological symptoms (27%). Chest X-ray revealed single or multiple nodular lesions in 10 patients; cavitation was observed in five patients. Tissue biopsy was the most common method of diagnosis (nine patients: lungs 6, liver 1, subcutaneous tissue 1, brain 1). Five IA cases were detected by nine guided fine needle lung biopsies in eight patients and without complications. Bronchoalveolar lavage was performed in 14 patients with findings suggestive of invasive pulmonary aspergillosis in eight cases. Lungs were the most common organ affected (90%) followed by central nervous system (41%). The diagnosis of IA is still difficult, and a large number of patients have advanced infection at diagnosis. Methods for early diagnosis are needed. Patients with a clinical suspicion of IA should be treated vigorously with antifungal agents during the diagnostic work-up.

Diagnosis of lower respiratory tract infections: what we have and what would be nice

STUDY OBJECTIVES

To review the various methods used to diagnose lower respiratory tract infections.

DESIGN

Review of literature with appropriate references to various techniques proposed to diagnose pneumonia.

INTERVENTION

Compare and contrast different proposed approaches to diagnose pneumonia.

RESULTS

Bronchoscopic techniques appear more clear cut for certain nonbacterial pathogens. Their role in immunocompromised patients is more clear cut, while in the nonimmunocompromised patient, invasive diagnostic techniques probably provide a higher certainty of the final diagnosis of the patient. Recent interest has focused on nonbronchoscopic techniques for the mechanically ventilated patient. None of these techniques has been demonstrated to change clinical outcome.

CONCLUSIONS

Diagnosis of lower respiratory tract infection has to be tailored for the individual patient. Decision about which procedure to do is influenced by the patient's underlying immune status, level of illness, and response to empiric therapy.

Bronchoscopic evaluation of pulmonary infiltrates following bone marrow transplantation

STUDY OBJECTIVE

To determine the impact of fiberoptic bronchoscopy (FOB), including quantitative bacterial cultures obtained by BAL and protected specimen brushing on therapeutic decisions and outcome in bone marrow transplant (BMT) patients.

DESIGN

Retrospective review of all BMT patients undergoing FOB during a 4-year period.

SETTING

A tertiary care university hospital.

RESULTS

Three hundred five patients underwent BMT; 71 (23%) had FOB to assess pulmonary infiltrates. Allogeneic BMT recipients underwent FOB 3.37 times more often than autologous recipients (p < 0.001). Pathogens were identified in 31 (46%) patients undergoing FOB; bacteria were most commonly isolated although 86% of patients had received broad-spectrum empiric antibiotics. Therapy was changed in 20 (65%) patients when a microorganism was identified and in 9 (22%) with nondiagnostic results (p = 0.0026), but isolation of a presumed pathogen had no apparent effect on survival. There were 19 (27%) FOB complications, including bleeding in 8 (11%) patients and death in 2 (3%). Major complications were associated with prolonged prothrombin time (p = 0.006) and were more common (36% vs 14%; p < 0.05) in patients who had protected specimen brushing vs BAL alone. Mortality at 40 months in BMT patients not requiring FOB was 33% compared with 61% mortality in those undergoing FOB (p < 0.001); mortality was 96% in patients with respiratory failure requiring mechanical ventilation.

CONCLUSION

FOB is diagnostically useful in the evaluation of some BMT patients with pulmonary complications and often influences therapy, although no impact on survival was clearly demonstrated. FOB should be performed only after benefits of the procedure are weighed carefully against its increased risk in this select population.

Thoracoscopy for diagnosis of diffuse lung disease

Diffuse lung diseases due to a wide variety of conditions are amenable to diagnosis by means of clinical evaluation, bronchoalveolar lavage, transbronchial biopsy, and lung biopsy. The recently introduced technique of thoracoscopic wedge biopsy provides the potential advantages of greater selection of biopsy sites and reduced postoperative pain compared with that associated with standard open lung biopsy. Its overall accuracy cited in initial reports has exceeded 90%. Although it is supplanting open lung biopsy as the most common operative technique for diagnosing diffuse pulmonary abnormalities, the availability of thoracoscopic lung biopsy should not alter the current indications for the initial use of bronchoscopic techniques in selected patients. In addition, because of the additional risk carried by thoracoscopic lung biopsy, open lung biopsy should still be used preferentially in patients suffering from acute decompensation, pulmonary hypertension, or coagulation disorders.

Bronchoscopy with bronchoalveolar lavage in the evaluation of pulmonary complications of bone marrow transplantation in children

Pulmonary complications are a frequent cause of morbidity and mortality following bone marrow transplantation. We examined the results of flexible bronchoscopy (FB) and bronchoalveolar lavage (BAL) in 27 pediatric bone marrow transplant (BMT) recipients with 29 episodes of pulmonary complications. Bone marrow transplant was performed for a variety of malignancies and hematologic disorders. Median age of BMT was 10.3 years (range, 1.7-17.6 years). Median time of FB following BMT was 60 days (range, 11-1,026 days). Routine cytologic and culture techniques were utilized to detect malignant cells, viruses, fungi, bacteria, and protozoa. Positive results were found in 15 (52%) with cytomegalovirus (CMV), the most common positive finding. In 14 (48%) episodes the results were negative. Fourteen patients had follow-up autopsy or open lung biopsy (OLB). Based on autopsy/OLB results, there were two false negatives and no false positives, giving a diagnostic sensitivity of 75% and specificity of 100%. There was one possible complication of FB and BAL. Survival of both positive and negative patients was poor, only seven patients being alive 90 days post-FB with BAL. We conclude that FB with BAL is a safe and accurate procedure for the diagnosis of pulmonary complications of BMT.