Bronchoalveolar lavage in HIV infected patients with interstitial pneumonitis

An official American Thoracic Society clinical practice guideline: classification, evaluation, and management of childhood interstitial lung disease in infancy

BACKGROUND

There is growing recognition and understanding of the entities that cause interstitial lung disease (ILD) in infants. These entities are distinct from those that cause ILD in older children and adults.

METHODS

A multidisciplinary panel was convened to develop evidence-based guidelines on the classification, diagnosis, and management of ILD in children, focusing on neonates and infants under 2 years of age. Recommendations were formulated using a systematic approach. Outcomes considered important included the accuracy of the diagnostic evaluation, complications of delayed or incorrect diagnosis, psychosocial complications affecting the patient's or family's quality of life, and death.

RESULTS

No controlled clinical trials were identified. Therefore, observational evidence and clinical experience informed judgments. These guidelines: (1) describe the clinical characteristics of neonates and infants (<2 yr of age) with diffuse lung disease (DLD); (2) list the common causes of DLD that should be eliminated during the evaluation of neonates and infants with DLD; (3) recommend methods for further clinical investigation of the remaining infants, who are regarded as having "childhood ILD syndrome"; (4) describe a new pathologic classification scheme of DLD in infants; (5) outline supportive and continuing care; and (6) suggest areas for future research.

CONCLUSIONS

After common causes of DLD are excluded, neonates and infants with childhood ILD syndrome should be evaluated by a knowledgeable subspecialist. The evaluation may include echocardiography, controlled ventilation high-resolution computed tomography, infant pulmonary function testing, bronchoscopy with bronchoalveolar lavage, genetic testing, and/or lung biopsy. Preventive care, family education, and support are essential.

Ineffectiveness of trimethoprim-sulfamethoxazole prophylaxis and the importance of bacterial and viral coinfections in African children with Pneumocystis carinii pneumonia

African human immunodeficiency virus type 1 (HIV-1)-infected children were evaluated to define the burden of Pneumocystis carinii pneumonia (PCP) and its interaction with bacterial and viral pathogens. P. carinii was identified in 101 (43.7%) of 231 episodes of pneumonia among 185 HIV-1-infected children (median age, 4.5 months; range, 1.7-27.3 months). Receipt of trimethoprim-sulfamethoxazole (TMP-SMX) prophylaxis was not associated with a significant reduction (36%; 95% confidence interval [CI], -15.4% to 64.5%) in isolation of P. carinii among children considered to have received adequate prophylaxis (37.7% of children) compared with children who had never received any prophylaxis (48.5% of children). However, deaths among children with PCP who had been taking TMP-SMX prophylaxis were markedly reduced (98.6%; 95% CI, 89.1%-99.8%) compared with children who were not taking prophylaxis. Concurrent P. carinii infection was observed in 6 of 18, 11 of 26, and 4 of 6 HIV-1-infected children who had bacteremia, a respiratory virus isolated, or Mycobacterium species isolated, respectively.

The emerging role of flexible bronchoscopy in pediatrics

Great advances had been made in rigid instrumentation, with the introduction of the glass rod telescope. With relatively few exceptions, however, bronchoscopy was still performed primarily for therapeutic indications, such as the removal of foreign bodies from the airway. It would remain for the introduction of the flexible bronchoscope to stimulate the widespread development of diagnostic bronchoscopy in pediatric practice.

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.

[Pulmonary complications in immunosuppressed children]

Pulmonary complications, which are dominated by opportunistic infections, can be first manifestations of inherited or acquired pediatric immune deficiencies. Prompt diagnosis is essential. The epidemiology and natural history of these complications have changed as a result of major advances in prevention, diagnosis and treatment.

Persistent and chronic lung disease in HIV-1 infected and uninfected African children

OBJECTIVE

The causes of persistent lung disease (PLD) and chronic lung disease (CLD) are unknown in HIV-infected children in developing countries. We describe the causes and course of PLD and CLD in HIV-infected and uninfected children.

METHOD

Of 194 children with lung disease persisting for at least 1 month who were seen at the paediatric respiratory clinic over a 2-year period, 42 underwent invasive investigations after failed initial management over 3 months. PLD was defined as the presence of clinical and radiological features of lung disease for more than 1 month, and CLD as these features for more than 3 months.

RESULTS

One hundred and thirty-eight (71%) of the 194 children with PLD were HIV-infected, 52 (27%) were not infected and four (2%) were of undetermined HIV status. Forty-eight per cent of the HIV-infected children and 52% of the HIV-uninfected children responded to initial treatment over 3 months; the presumptive diagnoses in these were tuberculosis, interstitial pneumonitis, bronchiectasis and post-ventilation lung syndrome. Of the 28 HIV-infected children with CLD who underwent invasive investigations 16 (57%) had lymphoid interstitial pneumonitis, eight (29%) had tuberculosis and four (14%) had non-specific interstitial pneumonitis. Of the 14 HIV-uninfected children with CLD who had invasive testing there were four cases (29%) each of tuberculosis and interstitial pneumonitis, three (22%) cases of bronchiectasis and one case of each of extrinsic allergic alveolitis, crytogenic fibrosing alveolitis and non-Hodgkin's lymphoma.

CONCLUSION

This is the first set of data on the causes of CLD in HIV-infected children in a developing country. Every effort should be made to identify the infectious agent, whether M. tuberculosis or a secondary bacterial infection in LIP, in order to treat most appropriately these children with lung disease.

The role of lung biopsy in children with perinatally acquired AIDS

There is a need for a rapid and efficacious method of diagnosis of pulmonary infiltrates in perinatal HIV infection. However, controversy still exists about which method--open lung biopsy (OLB) versus bronchoscopic techniques--is the best for this population. We present our results with OLB in 24 children with HIV-related lung disease. Over a 6-year period, 27 OLBs were performed on 24 children with diagnosis of HIV infection. The procedures were performed under general anesthesia using a limited anterolateral thoracotomy. Suspicious areas were removed with the autostapler. The specimens were studied for the presence of non-infectious as well as bacterial, viral, fungal, and mycobacterial diseases. There were no operative deaths related to the procedure. Morbidity was limited to prolonged but self-resolving air leaks in two patients (8.3%). Five hospital deaths occurred between 3 and 12 weeks postoperatively and 11 late deaths between 3 months and 6.5 years. All deaths were related to AIDS. Eight patients (33.3%) are still alive 2 to 8 years postoperatively. A total of 43 pathologies were found in 27 specimens. A positive pathologic finding was obtained in all patients, with two patients having nonspecific minimal changes. This resulted in a change of therapy in all but one case. The technique of OLB in children with AIDS is safe and simple. It should be performed early in the course of the disease and, a careful selection of candidates can minimize the incidence of complications.

Community respiratory viruses in individuals with human immunodeficiency virus infection

Respiratory viruses, particularly influenza viruses, respiratory syncytial virus (RSV), parainfluenza viruses, and adenoviruses, are ubiquitous pathogens among humans, especially among young children. However, relatively little is known about the impact of these common infections on individuals with the human immunodeficiency virus (HIV). A review of the literature identifies three key areas that need further exploration. First, moderate-to-severe and even fatal lower respiratory viral illnesses in HIV-infected individuals have been reported. In general, the clinical presentation of these respiratory viral infections in persons with HIV infection is similar to their presentation in individuals without HIV infection. The major exception is the occurrence of fulminant, and often fatal, disseminated adenovirus infection in adults and children with HIV disease. Despite these reports, no information is available regarding the frequency of moderate-to-severe respiratory viral illnesses in individuals with HIV infection. Epidemiologic studies of respiratory viral illnesses in cohorts of HIV-infected adults and children are needed. Second, prolonged shedding of respiratory viruses for weeks and even months has been documented in HIV-infected adults and children. The frequency of prolonged shedding in this population has not been well defined, but data from a small newborn cohort study suggest that, at least for RSV, prolonged shedding is common. Prolonged respiratory viral shedding has implications for infection control in medical facilities where HIV-infected individuals are treated and in nursing homes, child care centers, and group foster homes that provide care for HIV-infected individuals. Therapies to help eliminate these chronic viral infections should be explored. Finally, indirect evidence suggests that respiratory viral infection may result in changes in HIV replication and, theoretically, HIV disease progression. Increased HIV-1 replication has been demonstrated in vitro in T lymphoma cells exposed to genetic material from adenovirus. Increased HIV replication in peripheral blood from adults following inactivated influenza vaccination has been reported. The impact of natural respiratory viral infection (and perhaps vaccination against these pathogens) on HIV replication and disease progression will be an important area of study.

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.

HIV in children

Because children acquire HIV infection differently than adults, this article begins with a discussion of the epidemiology of AIDS in children. This is followed by a discussion of factors related to progression of the disease and survival in pediatric AIDS. A discussion of the pulmonary manifestations in children is followed by a suggested approach to the HIV-infected child with respiratory symptoms.

Pediatric human immunodeficiency virus infection

In the past decade, an increase in pediatric human immunodeficiency virus (HIV) infection has had a substantial impact on childhood morbidity and mortality worldwide. The vertical transmission of HIV from mother to infant accounts for the vast majority of these cases. Identification of HIV-infected pregnant women needs to be impoved so that appropriate therapy can be initiated for both mothers and infants. While recent data demonstrate a dramatic decrease in HIV transmission from a subset of women treated with zidovudine during pregnancy, further efforts at reducing transmission are desperately needed. This review focuses on vertically transmitted HIV infection in children, its epidemiology, diagnostic criteria, natural history, and clinical manifestations including infectious and noninfectious complications. An overview of the complex medical management of these children ensues, including the use of antiretroviral therapy. Opportunistic infection prophylaxis is reviewed, along with the important role of other supportive therapies.

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.

Role of tissue diagnosis in pulmonary involvement in pediatric human immunodeficiency virus infection

BACKGROUND

Pulmonary complications occur commonly during HIV infection. The aim of this study was to evaluate the clinical value of lung tissue examination in the diagnosis and treatment of pulmonary disorders in children with HIV infection.

METHODS

The medical records of 347 children enrolled between January, 1990, and April, 1994, into various antiretroviral therapy protocols were reviewed to identify patients who underwent a lung biopsy.

RESULTS

Fourteen patients underwent diagnostic lung biopsies on 16 separate occasions. The most common radiologic findings were nodular infiltrates which were localized in 7 patients and diffuse in 6. Eight patients presented with fever and progressive respiratory distress unresponsive to empiric therapy, whereas the rest had progressive nodular infiltrates. The pathologic diagnoses included opportunistic infection in 7 patients, lymphocytic interstitial pneumonitis in 5, non-Hodgkin's lymphoma in 3 and interstitial fibrosis in 1. The biopsy led to a major change in the treatment of 7 patients which resulted in a significant improvement of the pulmonary process in all of them. In an additional patient the excisional biopsy proved curative.

CONCLUSIONS

When patients are selected appropriately, lung biopsy might have a significant impact on therapy and outcome in HIV-infected children with pulmonary infiltrates.

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.

The role of flexible bronchoscopy in children with AIDS: an update of the New York University experience

The clinical courses of children with acquired immunodeficiency syndrome (AIDS) who underwent diagnostic flexible bronchoscopy at Bellevue Hospital from 1987-1992 were reviewed to determine the value of the procedure in patient management. Twenty-eight children (age 13 days to 12 years) underwent 31 bronchoscopies for indications including respiratory distress, fever and abnormal chest radiograph. Procedures were well tolerated. Complications were limited to transient hypoxia and epistaxis. Although 58% of bronchoscopies yielded a diagnosis (Pneumocystis carinii, Streptococcus viridans, Pseudomonas aeruginosa, Cytomegalovirus, atypical mycobacterium, giant cell pneumonia, and mechanical obstruction), empiric medical therapy was altered in only 16% of cases. Bronchoscopic diagnoses are correlated with Centers for Disease Control (CDC) classification, immune status, treatment and outcome.

Interstitial lung disease in children

Interstitial lung disease in children is a heterogeneous group of disorders of both known and unknown causes that share a common histologic characteristic (i.e., inflammation of the pulmonary interstitium that may resolve completely, partially, or progress to derangement of alveolar structures with varying degrees of fibrosis). The inflammatory process, evoked as a result of injury to alveolar epithelium and/or the endothelium, is responsible for alveolar wall thickening that is the histologic marker of ILD. This article extrapolates some of the known pathogenic mechanisms of ILD from adult and animal models and applies this information for a better understanding of the pathogenesis of ILD in children. The clinical manifestations vary and are often subtle and nonspecific. There is no consensus on specific criteria for the clinical diagnosis of ILD in children. There are no pathognomonic laboratory criteria for the diagnosis of ILD in children other than the characteristic findings on histologic examination of the lung. It is important to make the diagnosis early to minimize lung damage. Therapy is directed toward the reduction of the inflammatory response to minimize or prevent the progression to fibrosis. ILD suffers from lack of uniform guidelines for diagnostic evaluation, therapy, and prognostic indicators essential for critical monitoring of disease activity. No one medical center has enough cases of ILD in children to allow objective evaluation of a significant number of cases with adequate longitudinal follow-up to determine guidelines for optimal management and to identify accurate prognostic indicators. The organization of a multicenter approach will guide us towards a better understanding of ILD in children.

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.

Bronchoalveolar lavage

Bronchoalveolar lavage has a well established role in the diagnosis of pulmonary infections, particularly those due to opportunistic organisms in an immunocompromised host. Recent studies of infants and adults with inflammatory lung disease have helped our understanding of the mechanisms underlying these disorders and their responses to treatment. With increasing recognition that pulmonary events in utero and in early infancy are important in the pathogenesis of lung diseases such as asthma, studies of the lung's responses to various environmental insults in this population might guide us to developing effective preventative and therapeutic strategies. Bronchoalveolar lavage is one method for assessing a number of pulmonary components and may be useful in this regard, particularly if combined with new methods for examining inflammatory responses, such as those utilising the polymerase chain reaction to assess cellular expression for inflammatory cytokines and growth factors.

Nonbronchoscopic bronchoalveolar lavage in mechanically ventilated infants: technique, efficacy, and applications

Bronchoalveolar lavage with the fiberoptic bronchoscope is commonly used for the diagnosis of pulmonary infections in mechanically ventilated adults and children. However, its use for intubated infants is precluded because the small artificial airway does not permit the passage of the bronchoscope. We have developed a technique for nonbronchoscopic bronchoalveolar lavage, performed via a sterile, disposable feeding tube. We have used this technique in 15 infants with diffuse interstitial disease and/or atelectasis, while they were intubated and mechanically ventilated. The volume of the lavage effluent averaged 70.3% of the volume instilled. Specific diagnosis on the basis of the cytologic evaluation and/or culture of the lavage fluid was possible in 9 (60%) patients. Two patients with atelectasis showed radiographic evidence of improvement following the procedure. There were no complications. We conclude that nonbronchoscopic bronchoalveolar lavage is well tolerated, and clinically useful in small, mechanically ventilated infants with respiratory failure due to diffuse pulmonary disease. This technique provides a lower risk alternative to more invasive, and costly procedures.

Technique and use of transbronchial biopsy in children and adolescents

Since July 1988, a total of 92 transbronchial biopsies (TBB) have been performed in 18 patients (aged 3-16 years). Twelve patients (67%) were heart-lung transplant (HLT) recipients undergoing surveillance for pulmonary graft rejection and infection. The remainder included immunocompromised patients at risk of opportunistic infections (n = 4), patients with fibrosing alveolitis (n = 1) and a collagen vascular disorder with suspected lung involvement (n = 1). TBB was performed through either a fiberoptic (n = 50) or a rigid (n = 41) bronchoscope, all under general anesthesia. On one occasion a cardiac bioptome was used through an endotracheal stent. The sensitivity of TBB for diagnosing acute and chronic rejection in HLT patients was 88% and 60%, respectively (specificity, 91% and 100%). Definitive diagnoses were made in 4 (67%) of the non-HLT group. Bronchoalveolar lavage (BAL) was performed during each procedure for microbiological and cytological examination. Thirty-four pathogenic organisms including Pseudomonas aeruginosa (16/34), Staphylococcus aureus (8/34), and Candida albicans (5/34) were isolated from BAL culture. Complications included pneumothorax (8%), transient pyrexia (7%), and dyspnea (2%).

The value of flexible bronchoscopy in childhood pulmonary tuberculosis

The value of 121 flexible bronchoscopy (FB) procedures was evaluated in 54 children, aged three months to 14 years, suspected of having pulmonary tuberculosis. Specimens from FB were culture-positive for Mycobacterium tuberculosis in seven of the 13 bacteriologically confirmed cases. Bronchial abnormalities consistent with the diagnosis were found in 31 of 54 cases. Separate or coexistent findings at initial FB included airway compression (20 cases), granulation tissue (ten cases), and obstructive caseum (four cases). Chest roentgenograms underestimated bronchial involvement in 14 children. Further FB monitoring documented disease evolution. The FB was important in the management of patients, as it (1) guided the use of prednisone therapy, especially in the children with a chest roentgenogram not suggestive of bronchial involvement; (2) indicated a need for resection of granulation tissue by rigid bronchoscopy (three cases); and (3) guided the surgical decision (two children with persistent bronchial obstruction). Thus, FB is a safe and valuable procedure in the management of childhood pulmonary tuberculosis.

Lymphocytic interstitial pneumonia

Lymphocytic interstitial pneumonia is at present a pathologic diagnosis. In the setting of a chronic interstitial pneumonia in a child with lymphocytosis, hyperglobulinemia, and lymphadenopathy or parotid enlargement, the diagnosis is often clinically presumed. At present the diagnosis can be established firmly only by lung biopsy. Models of pathogenesis include nonspecific stimulation of the immune system, HIV-specific stimulation, or synergy between EBV and HIV. Treatment includes oxygen and bronchodilators as needed. The role of zidovudine and of steroids in the management of LIP remains to be determined.

Legionellosis in patients with HIV infection

During the five-year period 1984-1988 we received 192 specimens from 180 patients infected with the human immunodeficiency virus (HIV) for investigation of Legionella infection. The majority of specimens were bronchoalveolar lavage (BAL) fluids (84%), but tracheal suctions and lung tissue from autopsies were also examined. The diagnostic methods used were a direct immunofluorescence assay (DFA) for the detection of Legionella antigen, and culture on buffered charcoal yeast extract (BCYE-alpha) media. All specimens were also examined for the presence of other bacterial lung pathogens, and all BAL specimens additionally for Pneumocystis carinii and mycobacteria. Legionellosis was not found to be common among HIV-infected patients, as only six specimens (3%) from six patients were found positive by DFA, and no specimens were culture-positive for Legionella species. Dual infection with Legionella and P. carinii occurred in two patients. Clinical data of the six patients are presented, and currently used methods for diagnosing legionellosis are discussed.