Fungal pneumonia: the predominant lung infection causing death in children undergoing 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.

Time trends in fungal infections as a cause of death in hematopoietic stem cell transplant recipients: an autopsy study

Infectious complications remain an important cause of death in hematopoietic stem cell transplant (HSCT) recipients. We undertook a 20-year (1988-2007) retrospective review of all autopsies performed on HSCT recipients in our institution, with emphasis on infections, especially fungal infections, as the cause of death. Of the 2,943 autopsies performed in our institution from 1988 to 2007, 395 (13.4%) involved HSCT recipients (117 pediatric; 278 adult). Of the patients, 298 had received allogeneic, 46 autologous, 41 umbilical cord blood, and 3 autologous plus allogeneic types, and 7 were unknown HSCT types. The most common causes of death were pulmonary complications, occurring in 247 (62.5%) of 395 cases. In 178 cases (45.1%), microorganisms (viral, bacterial, and/or fungal) were documented at autopsy in one or more organs and contributed to the cause of death. Fungal infections were found in 23.5% of cases, but their frequency as a cause of death decreased throughout this study, from 30.3% in the 1988-1992 period to 10.9% in the 2003-2007 period.

Respiratory infections: pneumonia, lung abscess, and empyema

Pneumonia is an important clinical problem that affects children of all ages. Although effectively treated on an outpatient basis in the majority of cases, some children with respiratory infections still require hospitalization. This may be particularly true for patients with immunocompromise, for whom the lung represents the most common site of infection. Furthermore, respiratory infections represent a significant source of morbidity and mortality in this patient population. This article focuses on the clinical presentation, etiology, and treatment of childhood pneumonia, with special consideration given to the immunocompromised child. Two specific complications of pneumonia, lung abscess and empyema, are discussed.

Pulmonary Complications in Adult Blood and Marrow Transplant Recipients

STUDY OBJECTIVE

To describe the pulmonary findings at autopsy of blood and bone marrow transplant (BMT) recipients.

DESIGN

Retrospective.

SETTING

An academic medical center.

PATIENTS

Seventy-one deceased adult BMT recipients.

INTERVENTIONS

None.

MEASUREMENTS

Antemortem and postmortem pulmonary findings.

RESULTS

The transplants were allogeneic in 39 patients (55%), with a peripheral stem cell source in 43 patients (61%). Death occurred at a median of 1.30 months after transplant. Ninety-six pulmonary complications were noted in 63 patients (89%): 27 infectious (bacterial bronchopneumonia, n = 13; pulmonary aspergillosis, n = 11; cytomegalovirus pneumonia, n = 2; and Candida bronchopneumonia, n = 1) and 69 noninfectious (diffuse alveolar damage, n = 35; diffuse alveolar hemorrhage [DAH], n = 10; amyloidosis, n = 9; pulmonary embolism, n = 5; lymphoma/leukemia, n = 4; bronchiolitis obliterans, n = 2; bronchiolitis obliterans organizing pneumonia, n = 1; pulmonary alveolar proteinosis, n = 1; aspiration pneumonia, n = 1; and acute and organizing pneumonia, n = 1). Twenty-seven of the 96 complications (28%) were diagnosed antemortem. Infectious complications were more likely to be diagnosed antemortem compared to noninfectious complications (48% vs 20%, p = 0.006). Six of the 13 patients with bronchopneumonia (46%), 5 of the 11 patients with pulmonary aspergillosis (45%), and 7 of the 8 patients with DAH (88%) at autopsy were not receiving treatment for these conditions at the time of death. Ten patients being treated for suspected pulmonary aspergillosis, 7 patients treated for suspected pulmonary cytomegalovirus infection, 22 patients treated for suspected bacterial pneumonia, 2 patients treated for suspected Pneumocystis carinii pneumonia, and 12 patients treated for DAH at the time of death had no evidence of these conditions at autopsy. The most common immediate cause of death was respiratory failure (n = 37, 52%).

CONCLUSIONS

Pulmonary complications, the majority not diagnosed antemortem, are the most common cause of death in BMT recipients. As the result of underdiagnosis, BMT recipients may not receive appropriate therapy for potentially treatable pulmonary complications.

Pulmonary Complications After Bone Marrow Transplantation: An Autopsy Study From a Large Transplantation Center

Context.—Bone marrow transplantation (BMT) is used to treat various malignant and nonmalignant disorders. Pulmonary complications are some of the most common causes of mortality in BMT recipients. Poor general health and bleeding tendency frequently preclude the use of definitive diagnostic tests, such as open lung biopsy, in these patients.

Objective.—To identify pulmonary complications after BMT and their role as the cause of death (COD).

Design.—The autopsy and bronchoalveolar lavage (BAL) slides and microbiology studies of BMT recipients from a 7-year period were reviewed.

Results.—Pulmonary complications were identified in 40 (80%) of the 50 cases. The most common complications were diffuse alveolar damage (DAD) and diffuse alveolar hemorrhage (DAH). Pulmonary complications were the sole or 1 of multiple CODs in 37 cases (74%). All complications were more common in allogeneic BMT recipients. In 19 (51%) of the 37 cases in which pulmonary complications contributed to the death, cultures were negative. Both DAD and DAH, complications commonly reported in the early post-BMT period, were seen more than 100 days after BMT in 33% and 12% of cases, respectively. Five (83%) of 6 cases of invasive pulmonary aspergillosis diagnosed at autopsy were negative for fungi ante mortem (by BAL and cultures).

Conclusions.—Pulmonary complications are a significant COD in BMT recipients, many of which, especially the fungal infections, are difficult to diagnose ante mortem. The etiology of DAD and DAH is likely to be multifactorial, and these complications are not limited to the early posttransplantation period. Autopsy examination is important in determining the COD in BMT recipients.

Role of flexible bronchoscopy in immunocompromised patients with lung infiltrates

STUDY OBJECTIVE

To study the diagnostic role of flexible bronchoscopy (FB) in immunocompromised patients with pulmonary infiltrates.

DESIGN

Prospective, observational study.

SETTING

Tertiary care hospital.

PATIENTS

A total of 104 consecutive non-HIV-infected immunocompromised patients with lung infiltrates in whom FB was performed.

METHODS

The primary outcome measure was the diagnostic yield of FB, which was derived as the number of the diagnoses made using FB results divided by all final diagnoses. Final diagnoses were established using data from FB, surgical lung biopsy (SLB), and microbiology and serology testing, and by the clinical response to empiric therapy. We also studied the diagnostic yields of individual sampling procedures such as BAL, transbronchial biopsy (TBB), and protected-specimen brush (PSB) sampling.

RESULTS

Overall, 128 diagnoses were made in 104 patients. The overall diagnostic yield of FB was 56.2% (95% confidence interval [CI], 47 to 64%). FB provided at least one diagnosis in 53 of 104 patients (51%; 95% CI, 40 to 62%). FB was more likely to establish the diagnosis when the lung infiltrate was due to an infectious agent (81%; 95% CI, 67 to 90%) than to a noninfectious process (56%; 95% CI, 43 to 67%; p = 0.011). The diagnostic yields of BAL (38%; 95% CI, 30 to 47%) and TBB (38%; 95% CI, 27 to 51%) were similar (p = 0.94). The diagnostic yield of PSB sampling was lower (13%; 95% CI 6 to 24%; p = 0.001) than that of BAL. The combined diagnostic yield of BAL and TBB (70%; 95% CI, 57 to 80%) was higher than that of BAL alone (p < 0.001). Finally, the diagnostic yield of FB with PSB sampling, BAL, and TBB was similar to that of FB with BAL and TBB. The complication rate from FB was 21% (95% CI, 15 to 31%). Minor bleeding (13%) and pneumothorax (4%) were the most common complications.

CONCLUSIONS

FB has a high diagnostic yield in immunocompromised patients with pulmonary infiltrates. Based on our results, we recommend performing TBB in these patients, whenever possible.

Pediatric bronchoscopy

Diagnostic flexible endoscopy for pediatric respiratory diseases is performed in many centers. Technical advances have resulted in performance of interventional bronchoscopies, and new diagnostic indications are being explored. Indications with documented clinical benefit include congenital or acquired progressive or unexplained airway obstruction. Pulmonary infections in immunodeficient children who do not respond to empirical antibiotic treatment may be diagnosed by bronchoscopy and bronchoalveolar lavage (BAL). The potential usefulness of bronchoscopy and BAL for managing chronic cough, wheeze, or selected cases with asthma or cystic fibrosis requires further study. The use of transbronchial biopsies (TBB) is established in pediatric lung transplantation. The role of TBB in the diagnosis of chronic interstitial lung disease in children remains to be determined. For a number of interventional applications, rigid endoscopy is required, and pediatric bronchoscopists should be trained in its use. Complications in pediatric bronchoscopy are rare, but severe nosocomial infection or overdosing with local anesthetics has occurred. The issues of quality control, video documentation, interobserver variability of findings, and educational standards will have to be addressed in the future as bronchoscopy use becomes less restricted to only large pediatric pulmonary units.

Yield of bronchoalveolar lavage in ventilated and non-ventilated children after bone marrow transplantation

A study was undertaken to retrospectively evaluate the yield of bronchoalveolar lavage (BAL) in a single-institution series of children after bone marrow transplantation (BMT) and to compare the yield of BAL between the ventilated and nonventilated patients. We reviewed charts of 52 consecutive children after BMT who underwent BAL. Thirty patients (41 BALs) were nonventilated (group 1) and 33 patients (45 BALs) were ventilated for respiratory failure (group 2). Eleven patients were included in both groups. BAL was performed a median of 255 and 28.5 days after BMT in groups 1 and 2, respectively (P < 0.001). Group 1:17 pathogens were isolated from 13 BALs; a single pathogen from 10 BALs. Group 2:15 pathogens were isolated from 14 BALs (31.1% positive). Viruses were isolated from 13 BALs in group 2. A severe complication of BAL occurred in only one patient from group 1 (1.1%). Open lung biopsies were performed in one patient in group 1 and eight patients in group 2. The histological findings correlated with the BAL findings in 66.7%. In conclusion, there was no difference in the yield of BAL between the groups. Therapy was changed in one third of the patients dictated by the BAL findings. The risk of severe complications was relatively low. A good correlation between open lung biopsy (OLB) and BAL was found.

Pulmonary cytolytic thrombi: a previously unrecognized complication of bone marrow transplantation

Lung injury is a frequent and severe complication of bone marrow transplantation (BMT). Over the past 5 years we have recognized a new noninfectious pulmonary complication of allogeneic BMT in 12 patients, presenting with fever, pulmonary nodules on chest computed tomography, and distinctive histopathologic appearance descriptively termed "pulmonary cytolytic thrombi" (PCT). All but one patient were children transplanted for malignant (9) and nonmalignant (3) conditions. Ten of the patients had active graft-versus-host disease (GVHD) of skin, bowel, or both at the time of diagnosis of the PCT. In all cases occlusive vascular lesions were present, most of them associated with hemorrhagic infarcts. The endothelial cell layer was discontinuous in all cases stained with antibody to CD31. The thrombi had entrapped recognizable leukocytes and CD45-positive cell fragments embedded in a tenacious basophilic material. The symptoms and radiologic findings resolved in weeks to months. PCT may represent a previously unrecognized form of pulmonary acute GVHD.

Fluconazole vs low-dose amphotericin B for the prevention of fungal infections in patients undergoing bone marrow transplantation: a study of the North American Marrow Transplant Group

Systemic fungal infections are a major problem in bone marrow transplant recipients who have prolonged neutropenia or who receive high-dose corticosteroids. Prophylaxis with Fluconazole or low-dose amphotericin B reduces, but does not eliminate these infections. To determine which prophylactic agent is better, we performed a prospective randomized study. Patients undergoing allogeneic (related or unrelated) or autologous marrow or peripheral stem cell transplantation were randomized to receive Fluconazole (400 mg/day p. o. or i.v.) or amphotericin B (0.2 mg/kg/day i.v.) beginning 1 day prior to stem cell transplantation and continuing until recovery of neutrophils to >500/microl. Patients were removed from their study drug for drug-associated toxicity, invasive fungal infection or suspected fungal infection (defined as the presence of fever >38 degrees C without positive culture while on broad-spectrum anti-bacterial antibiotics). Proven or suspected fungal infections were treated with high-dose amphotericin B (0.5-0.7 mg/kg/day). Patients were randomized at each institution and stratified for the type of transplant. The primary end-point of the study was prevention of documented fungal infection; secondary endpoints included fungal colonization, drug toxicity, duration of hospitalization, duration of fever, duration of neutropenia, duration and total dose of high-dose amphotericin B and overall survival to hospital discharge. From July 1992 to October 1994, a total of 355 patients entered into the trial with 159 patients randomized to amphotericin B and 196 to Fluconazole. Patient groups were comparable for diagnosis, age, sex, prior antibiotic or antifungal therapy, use of corticosteroids prior to transplantation and total duration of neutropenia. Amphotericin B was significantly more toxic than Fluconazole especially in related allogeneic transplantation where 19% of patients developed toxicity vs 0% of Fluconazole recipients (p < 0.05). Approximately 44% of all patients were removed from prophylaxis for presumed fungal infection. Proven fungal infections occurred in 4.1% and 7.5% of Fluconazole and amphotericin-treated patients, respectively. Proven fungal infections occurred in 9.1% and 14.3% of related allogeneic marrow recipients receiving Fluconazole or amphotericin B, respectively, and 2.1% and 5.6% of autologous marrow recipients receiving Fluconazole or amphotericin B, respectively (P > 0.05). In this prospective trial, low-dose amphotericin B prophylaxis was as effective as Fluconazole prophylaxis, but Fluconazole was significantly better tolerated.

Pulmonary cytolytic thrombi: a newly recognized complication of stem cell transplantation

Over the past 5 years we have recognized a new pulmonary complication of hematopoietic stem cell transplantation (HSCT) associated with fever and pulmonary nodules termed 'pulmonary cytolytic thrombi' (PCT). Retrospective analysis of medical and radiographic records and pathologic material from 13 HSCT recipients with PCT and a review of the Blood and Marrow Transplant Database for all patients with radiographic evidence of pulmonary nodules or who underwent open-lung biopsy from 1 January 1993 to 31 December 1998 (n = 1228) were performed. The median age of patients with PCT was 11.9 years (range, 1.3-29.7 years). All patients developed fever at a median of 72 days (range, 8-343 days) post transplant, followed by pulmonary nodules on chest CT. Eleven patients were receiving therapy for active GVHD (acute, grades I-IV (n = 10); extensive chronic (n = 1)). Biopsy of the pulmonary nodules revealed a unique pattern of necrotic, basophilic thromboemboli with amorphous material suggestive of cellular breakdown products. This was descriptively labeled 'pulmonary cytolytic thrombi'. Immunohistochemical staining revealed entrapped leukocytes and disrupted endothelium, but was negative for histiocytes. Cultures and immunohistochemical stains were negative for infectious agents. Empiric therapy included systemic corticosteroids (n = 9) and amphotericin (n = 7). Nine patients survive with resolution of PCT at a median follow-up of 1.5 years. Bone Marrow Transplantation (2000) 25, 293-300.