The diagnosis of pneumonia in the immunocompromised child: use of bronchoalveolar lavage

Acute lung pathology in the immunocompromised child

Children with compromised immune systems, whether due to primary or secondary immunodeficiencies, are susceptible to a broad spectrum of acute intrathoracic pathologies. These include infections, pulmonary edema, and malignancies. Pulmonary issues are common and perilous in this population, necessitating prompt and precise diagnosis for effective management. This review aims to provide an overview of such conditions, focusing on the imaging appearances of the most prevalent acute lung conditions affecting immunocompromised children. It emphasizes the critical importance of an integrated clinical and radiological approach when diagnosing these acute pulmonary disease states.

Pulmonary complications following adult liver transplantation

PURPOSE

Pulmonary complications frequently occur after liver transplantation, but the risk factors associated with them have not been fully determined. We therefore sought to identify risk factors for pulmonary complications among adult liver transplant recipients.

METHODS

We retrospectively reviewed the medical records of 128 consecutive adult patients who underwent 131 liver transplantations during 2001. We evaluated the incidence, time of onset, and outcome of radiographically determined pulmonary complications, as well as the factors predictive of infectious complications.

RESULTS

Postoperative chest roentgenograms detected 68 cases of pulmonary complications, including pleural effusion (n = 50), atelectasis (n = 6), pneumonia (n = 6), pulmonary edema (n = 5), and acute respiratory distress syndrome associated with pneumonia (n = 1). Of the seven patients with pneumonia, five died. On univariate analysis the risk factors predictive for pneumonia were high serum creatinine and total bilirubin, hemodialysis at the time of occurrence, and history of acute rejection and on multivariate analysis increased total bilirubin and history of acute rejection. Pulmonary complications were dependent on the medical condition at the time of occurrence rather than on the preoperative condition.

CONCLUSIONS

Although the incidence of pneumonia in liver recipients was relatively low, the mortality rate in patients who developed this complication was high. High-risk patients undergoing liver transplantation thus require early diagnosis and intensive treatment to diminish the morbidity and mortality associated with pulmonary complications.

Clinical utility of bronchoalveolar lavage in pediatric cancer patients

BACKGROUND

Pulmonary disease in the pediatric cancer patient continues to pose a difficult clinical dilemma. Bronchoalveolar lavage (BAL) is commonly utilized for the diagnosis of pulmonary complications in the immunocompromised child.

PROCEDURE

We retrospectively reviewed 53 BAL procedures performed in pediatric cancer patients with pulmonary disease between 1988 and 1998 to determine the diagnostic and clinical utility of BAL. Patients who had undergone prior myeloablative therapy were excluded from analysis.

RESULTS

The majority of patients (83%) had an underlying diagnosis of acute leukemia or lymphoma. BAL yielded a specific diagnosis in 16 patients (30%), including 15 infections and 1 malignant infiltration. Medical management was altered in an additional 14 patients (26%) as a consequence of a negative BAL result. Severe but transient complications associated with the BAL procedure occurred in four patients (8%). Minor complications following the BAL occurred in 21 patients (40%) and included transiently increased oxygen requirement and anesthesia-related gastrointestinal complaints. The mortality from lung disease in this patient population was 7.5%.

CONCLUSIONS

Both positive and negative BAL results contribute to the management of pediatric cancer patients with pulmonary disease. The low incidence of significant complications associated with BAL and the high mortality rate in this patient population support the choice of BAL as an initial diagnostic test in pediatric cancer patients with pulmonary disease.

Usefulness of bronchoalveolar lavage for the diagnosis and treatment of refractory pneumonia in a patient with Kostmann syndrome, a severe congenital neutropenia

An 11-year-old girl with Kostmann syndrome developed refractory pneumonia. Culture of oral discharge, throat-swab specimens, and blood could not identity the causative organism, and systemic antimicrobial therapy failed to achieve improvement. We then performed diagnostic bronchoalveolar lavage (BAL) and culture of BAL fluid (BALF) yielded Pseudomonas aeruginosa. Therapeutic BAL using gentamicin produced a striking improvement of her pneumonia.

CONCLUSION

In immunocompromised children with pneumonia, BAL helps to identify the causative organism. If the patient is unresponsive to systemic antimicrobial therapy, BAL using antimicrobial agents is also worth trying.

Value of open lung biopsy in immunocompromised children

OBJECTIVES

To determine the value of open lung biopsy (OLB) in terms of diagnosis, morbidity, mortality, and benefits in immunocompromised children with pulmonary involvement.

STUDY DESIGN

We retrospectively reviewed 36 OLBs performed in 32 immunocompromised children between 1985 and 1998. Seventeen biopsies were performed in patients with primary immunodeficiency syndromes and 19 in patients with secondary immunodeficiency syndromes. Twenty-eight biopsies were performed because of a lack of response to ongoing antimicrobial treatments with negative or positive findings on bronchoalveolar lavage (BAL) and a deteriorating clinical or radiologic course, and 8 biopsies were performed because of persistent chest x-ray infiltrates.

RESULTS

Diffuse pulmonary infiltrates were observed on chest x-ray in 28 cases, hyperinflation in 3 cases, and nodular infiltrates in 5 cases. A histopathologic diagnosis was possible for all 36 OLBs. Specific diagnosis was obtained in 22 (61%) (12 infectious agents, 6 tumors, 4 bronchiolitis obliterans) and non-specific diagnosis in 14 (39%). Fungi were the main infectious agents (8 of 12). For the diagnosed infections, BAL provided 4 true-positive, 3 false-positive, and 6 false-negative results. Specific treatment was changed in 77% of cases, providing real benefits in 12 (33%) cases. The morbidity and overall mortality rates were 31% and 33%, respectively. The mortality rate was significantly higher in the first 30 days after OLB in patients receiving ventilatory assistance (58%).

CONCLUSIONS

OLB in immunocompromised children with deteriorating clinical or radiologic course is a sensitive diagnostic tool.

Protected specimen brush or bronchoalveolar lavage to diagnose bacterial nosocomial pneumonia in ventilated adults: a meta-analysis

OBJECTIVE

We conducted a meta-analysis by using summary receiver operating characteristic curves to compare the diagnostic value for bacterial nosocomial pneumonia of the following: a) quantitative culture (colony-forming units per milliliter or CFU/mL) of respiratory secretions collected with a bronchoscopic protected specimen brush (PSB); b) quantitative culture of a bronchoscopic bronchoalveolar lavage (BAL); and c) the percentage of infected cells (IC) in BAL.

DATA SOURCES

All studies published in the English or the French language, through January 1, 1995, on the evaluation of PSB or BAL for the diagnosis of pneumonia were considered for analysis. The relevant literature was identified through computer and reference searching and by experts in the field.

STUDY SELECTION

A study was included if at least two of three independent readers regarded its purpose as the evaluation of CFU-PSB, CFU-BAL, or IC-BAL for the diagnosis in human beings of bacterial nosocomial pneumonia in ventilated adults and if the study was prospective and published in a peer-reviewed journal.

DATA EXTRACTION

Three readers reviewed all published articles and decided whether to include each study; consensus was defined as agreement by at least two readers. The authors of each original article included in the meta-analysis were asked to complete a questionnaire in which they were asked to check and to correct the data extracted by one of the independent readers.

DATA SYNTHESIS

Summary receiver operating characteristic curves were used to compare the efficacy of three diagnostic tests. Eighteen studies on CFU-PSB (795 patients) were included, as well as 11 studies on CFU-BAL (435 patients) and 11 on IC-BAL (766 patients). The accuracy of these tests was not different. However, it seems that administration of previous antibiotics markedly decreased accuracy of CFU-PSB (p = .0002) but not the accuracy of CFU-BAL and that of IC-BAL.

CONCLUSION

Both PSB and BAL are reliable to diagnose bacterial nosocomial pneumonia. Because CFU-BAL and IC-BAL seemed more resistant to the effects of antibiotics, we recommend BAL rather than PSB if the patient is already receiving antibiotics.

Intrapulmonary protein leakage in immunocompromised children and adults with pneumonia

BACKGROUND

Pulmonary infections are associated with an increase in capillary permeability but information regarding age related differences in the local inflammatory response is lacking. To quantify the degree of capillary leakage during inflammation, the concentrations of the plasma proteins albumin, alpha1-antitrypsin, alpha2-macroglobulin and the locally produced proteins elastase, myeloperoxidase, lactoferrin and fibronectin were studied in the bronchoalveolar lavage (BAL) fluid of immunosuppressed children and adults with pneumonia.

METHODS

Sixteen children aged 2-16 years and 15 adults who developed pneumonia while receiving immunosuppressive therapy for haematological malignancies were included in the study. Bronchoalveolar lavage was performed via a flexible bronchoscope with three aliquots of 1 ml/kg body weight in children and 200 ml in adults. Protein concentrations in BAL fluid were determined using highly sensitive immunoluminometric assays.

RESULTS

Despite considerable variability, the median concentrations of all proteins in BAL fluid were significantly higher in both patient populations than in previously collected age adjusted reference values. The concentrations of serum derived proteins were significantly higher in children with pneumonia than in adult patients. In contrast, no differences were observed between the two groups for locally produced proteins.

CONCLUSIONS

These data suggest that the degree of protein exudation is more pronounced in immunosuppressed children with pneumonia than in adults in a similar clinical situation. This is in agreement with our studies in healthy individuals and may reflect a greater permeability of the alveolar-capillary membrane in children, regardless of disease status.

The diagnostic value of bronchoalveolar lavage in immunocompetent children with chronic diffuse pulmonary infiltrates

We have investigated the diagnostic value of (BAL) in 29 immunocompetent children (ages 1 month to 18 years) with chronic diffuse pulmonary infiltrates on chest radiograph who presented for evaluation over a 3-year period. The median age at the time of the BAL was 20 months with a range of 1-210 months. Positive results (1) diagnostic of a primary disorder; (2) consistent with a diagnosis; or (3) diagnostic of a secondary disorder, were obtained in 20/29 patients (13 with a single positive BAL finding and 7 with more than one finding). BAL was diagnostic of a primary disorder in only 5 patients (17%) with aspiration detected in 3 and infection in 2. The differential diagnosis was narrowed in 15 patients by the presence of lymphocytosis, neutrophilia, or eosinophilia. A secondary disorder was uncovered in 8 patients. Negative results were obtained in 9 additional patients. We conclude that BAL provided useful information in children with chronic diffuse infiltrates, but its ability to determine the primary cause was limited.

Role of bronchoalveolar lavage in hospitalized pediatric patients

Bronchoalveolar lavage (BAL) has been shown to be a rapid, relatively safe, and relatively noninvasive diagnostic procedure. Theoretically, BAL can be performed on all children hospitalized for pneumonia resistant to oral antibiotics, though practically and economically, this is not feasible. A 1-year retrospective review was conducted to define a cost-effective role for BAL in the management of hospitalized children with resistant pneumonia. The data revealed identification of at least one pathogen in 87% of sputum samples and in 95% of BAL specimens. Sputum samples provided the same information as the more invasive BAL technique in 60% of patients who had both sputum and BAL obtained for culture. Recommendations are made for the use of BAL as a diagnostic tool in the hospitalized child with resistant pneumonia.

Comparison of cell profiles in separately evaluated fractions of bronchoalveolar lavage (BAL) fluid in children

BACKGROUND

Bronchoalveolar lavage (BAL) has been widely accepted as a routine procedure in the differential diagnosis of respiratory diseases in adults. However, there is only limited information about the value of BAL in children and there is no standardisation of the procedures.

METHODS

The difference in cellular profiles of sequential BAL fractions from children was analysed to assess the effect of evaluating bronchial and alveolar fractions separately. Twenty five children (mean age 13.4 years) were examined by fibreoptic bronchoscopy under general anaesthesia, combined with local application of lignocaine. The investigation was part of the clinical evaluation of an infective pulmonary problem. Bronchoalveolar lavage was performed from the right middle lobe using four 20 ml aliquots of normal saline and the four fractions of recovered fluid were evaluated separately.

RESULTS

The total cell count was lowest in the first aspirate (1.8 x 10(6)) and increased gradually from fraction 1 to fraction 4. Similarly, the viability of the cells was lowest in fraction 1 and gradually improved from fraction 1 to fraction 4. In the differential count the number of neutrophils decreased from fraction 1 (8.3%) to fraction 4, with fractions 2 (5.4%), 3 (3.4%), and 4 (2.4%) being significantly different from fraction 1. There were no differences in the numbers of eosinophils, lymphocytes, or macrophages between individual fractions.

CONCLUSIONS

These results show that the cell profile of the first "bronchial" fraction is different from subsequent samples. It should be evaluated separately while the second and third aliquots may be pooled.

Differential cytology of bronchoalveolar lavage fluid in immunosuppressed children with pulmonary infiltrates

OBJECTIVE

Bronchoalveolar lavage (BAL) is a well established technique for the detection of pathogens in immunosuppressed children, but its diagnostic yield is variable. The aim of this study was to investigate whether BAL differential cell counts are helpful in the evaluation of pulmonary infiltrates in immunocompromised children.

STUDY DESIGN

BAL was performed 28 times in 27 febrile immunocompromised children with pulmonary infiltrates. All patients were pretreated with broad spectrum antibiotics; 11 children also received amphotericin B. BAL was conducted with a flexible bronchoscope wedged in the area of maximal pathology as suggested by the chest radiograph or in the middle lobe in patients with diffuse interstitial radiographic changes. Differential cell counts were performed from cell smears obtained after centrifugation of BAL fluid.

RESULTS

Bacterial or fungal organisms were detected in BAL fluid of 12 patients. Patients with bacterial or fungal infections (group 1) had a significantly higher percentage of granulocytes in BAL fluid both compared with patients with sterile BAL cultures (group 2) and with a control group of children without pulmonary disease (p < 0.001, Wilcoxon test). The proportion of lymphocytes was not different from the control group in group 1 but significantly increased in group 2 (p < 0.001, Wilcoxon test). Blood differential cell counts were not different in the two patient groups. Lymphocyte subsets of BAL fluid obtained in a subgroup of patients were not significantly different from controls.

CONCLUSION

These data suggest that BAL differential cell counts may be a useful adjunct in the differential diagnosis of pulmonary infection in immunocompromised children.

Bronchoalveolar lavage studies in children without parenchymal lung disease: cellular constituents and protein levels

We evaluated bronchoalveolar lavage fluid (BAL) for cellular constituents, concentration of total protein (TP), albumin (AL), fibronectin (FN), and hyaluronic acid (HA) in 16 children aged 2-32 months without pulmonary inflammatory or parenchymal disease to establish reference values. We compared our data to those reported in older children and in normal adult volunteers. BAL results were obtained simultaneously from the right middle lobe and the lingula. Results indicated that children younger than 3 years of age had a higher number of cells/mL than older children and adults (59.9 x 10(4) vs. 17.6 x 10(4) and 12 x 10(4)). Differential cell count revealed that the percentages of alveolar macrophages (AM), lymphocytes (LYM), and eosinophils (EOS) were similar to those obtained in older children and in adults, whereas the percentage of neutrophils (NEU) was higher in younger children (NEU 5.5 vs 1.6 and 1.2%, respectively) than in older children and adults. The latter difference was even greater in infants under 12 months of age (NEU 7.6%). The concentrations of TP, AL, FN, and HA in children's BAL samples were compared to values reported for adults. There were no differences between infants and children 13-32 months of age or normal adults. BAL fluid obtained simultaneously from the middle lobe and lingula were not significantly different. In conclusion, this is the first report on BAL values (cellular and noncellular constituents) in children younger than 3 years. The results may be used as reference values for further studies in children with parenchymal lung disease in this age group.

Assessment of lung function in the intensive care unit

Tests of pulmonary function have become more accurate and less invasive in recent years. Our ability to monitor patients continuously with pulse oximetry, transcutaneous and end-tidal CO2, and intraarterial blood gas monitors has greatly enhanced ICU care. In intubated patients in the PICU detailed lung function studies can be performed, and in general they can be carried out with minimal disruption of routine management. Much work remains to be done to define the changes seen in various disease processes and the effects of therapeutic interventions on functional parameters. Many of the available techniques have already been developed to a point that allows them to be employed in clinical decision making. We expect that assessment of lung volumes, compliance, and resistance will become a routine part of management in children with life-threatening pulmonary diseases in the near future, and that a more intimate knowledge of the pathophysiology of respiratory disorders treated in PICU will lead to improved outcomes.

Update on pediatric flexible bronchoscopy

Technological advances in flexible bronchoscopy have expanded the clinician's ability to diagnose and treat pulmonary disease in children. During the neonatal period, flexible bronchoscopy has contributed to the understanding of the incidence and factors responsible for acquired airway lesions. The ability to selectively collect lower airway secretions has contributed to the care of immunocompromised patients with new pulmonary infiltrates. New therapies may use the flexible bronchoscope to specifically target lower airway tissues of interest. Because of the breadth of both current and future applications, most pediatricians will require a working familiarity with the benefits of flexible bronchoscopy in their patients.

Surgical complications in children after liver transplantation

The frequency of surgical complications after liver transplantation remains high. Sixty transplants were done in 48 patients during 4 years. Eleven patients were retransplanted (re-transplant rate, 20%) for primary nonfunction (6), arterial thrombosis (3), warm ischemia (1), and rejection (2). Right pleural effusions were drained in 13 patients and left ones in 2. Forty-eight re-explorations excluding retransplantation were performed in 20 patients. Twelve laparotomies were for control of postoperative intraabdominal bleeding. The majority of these patients (8/10, 80%) were transplanted with reduced-size grafts. Early postoperative vascular complications were detected in 12 grafts (5 portal vein occlusions, 7 arterial thromboses). All 5 patients with portal vein (PV) occlusions were reexplored, and PV flow was reestablished in all 5. Biliary leaks were diagnosed in 6 patients and were associated with arterial thromboses in 2 cases. Reoperation was required in 4 of 6 patients. Bowel perforation occurred in 4 patients; 2 small bowel, 1 duodenum, and 1 colon. There was 1 postoperative bowel obstruction requiring laparotomy. Two splenectomies were required in 4 patients with splenic infarction. Resection of part of a transplanted liver was done in 1 patient to exclude septic infarcts. Pancreatitis was diagnosed in 4 patients and one required laparotomy for control of pancreatic hemorrhage. Intraabdominal abscesses required open drainage in 2 patients and percutaneous drainage in 4. Seven thoracotomies were done in 6 patients: 5 open lung biopsies, 1 for control of hemorrhage, and 1 for diaphragmatic plication. The current high survival rates following liver transplantation require aggressive surgical management of a myriad of complications and numerous procedures are necessary both as treatment modalities and as diagnostic aids.