Bronchiectasis in children with lymphocytic interstitial pneumonia and acquired immune deficiency syndrome. Plain film and CT observations

Examining the Complex Relationship Between Tuberculosis and Other Infectious Diseases in Children

Millions of children are exposed to tuberculosis (TB) each year, many of which become infected with Mycobacterium tuberculosis. Most children can immunologically contain or eradicate the organism without pathology developing. However, in a minority, the organism overcomes the immunological constraints, proliferates and causes TB disease. Each year a million children develop TB disease, with a quarter dying. While it is known that young children and those with immunodeficiencies are at increased risk of progression from TB infection to TB disease, our understanding of risk factors for this transition is limited. The most immunologically disruptive process that can happen during childhood is infection with another pathogen and yet the impact of co-infections on TB risk is poorly investigated. Many diseases have overlapping geographical distributions to TB and affect similar patient populations. It is therefore likely that infection with viruses, bacteria, fungi and protozoa may impact on the risk of developing TB disease following exposure and infection, although disentangling correlation and causation is challenging. As vaccinations also disrupt immunological pathways, these may also impact on TB risk. In this article we describe the pediatric immune response to M. tuberculosis and then review the existing evidence of the impact of co-infection with other pathogens, as well as vaccination, on the host response to M. tuberculosis. We focus on the impact of other organisms on the risk of TB disease in children, in particularly evaluating if co-infections drive host immune responses in an age-dependent way. We finally propose priorities for future research in this field. An improved understanding of the impact of co-infections on TB could assist in TB control strategies, vaccine development (for TB vaccines or vaccines for other organisms), TB treatment approaches and TB diagnostics.

HRCT findings of childhood follicular bronchiolitis

BACKGROUND

Follicular bronchiolitis is a lymphoproliferative form of interstitial lung disease (ILD) defined by the presence of peribronchial lymphoid follicles. Follicular bronchiolitis has been associated with viral infection, autoimmune disease and immunodeficiency. The most common clinical manifestation is respiratory distress in infancy followed by a prolonged course with gradual improvement. We found no reports of systematic review of high-resolution computed tomography (HRCT) findings in pediatric follicular bronchiolitis.

OBJECTIVE

The purpose of this study was to describe the HRCT findings of follicular bronchiolitis in children and correlate these imaging findings with histopathology.

MATERIALS AND METHODS

A 5-year retrospective review of all pathology-proven cases of follicular bronchiolitis was performed. Inclusion criteria were age <18 years and an HRCT within 6 months of lung biopsy. HRCTs were reviewed by three observers and scored using the system previously described by Brody et al.

RESULTS

Six patients met the inclusion criteria with age range at HRCT of 7-82 months (median: 39.5 months). Pulmonary nodules (n=6) were the most common HRCT finding followed by focal consolidation (n=5), bronchiectasis (n=4) and lymphadenopathy (n=3). Tree and bud opacities and nodules on CT correlated with interstitial lymphocytic infiltrates and discrete lymphoid follicles on pathology.

CONCLUSION

The salient HRCT findings of childhood follicular bronchiolitis are bilateral, lower lung zone predominant pulmonary nodules and bronchiectasis with infantile onset of symptoms. These characteristic HRCT findings help differentiate follicular bronchiolitis from other forms of infantile onset ILD.

The Role of Infection in Interstitial Lung Diseases: A Review

Interstitial lung disease (ILD) comprises an array of heterogeneous parenchymal lung diseases that are associated with a spectrum of pathologic, radiologic, and clinical manifestations. There are ILDs with known causes and those that are idiopathic, making treatment strategies challenging. Prognosis can vary according to the type of ILD, but many exhibit gradual progression with an unpredictable clinical course in individual patients, as seen in idiopathic pulmonary fibrosis and the phenomenon of "acute exacerbation"(AE). Given the often poor prognosis of these patients, the search for a reversible cause of respiratory worsening remains paramount. Infections have been theorized to play a role in ILDs, both in the pathogenesis of ILD and as potential triggers of AE. Research efforts thus far have shown the highest association with viral pathogens; however, fungal and bacterial organisms have also been implicated. This review aims to summarize the current knowledge on the role of infections in the setting of ILD.

Lymphocytic Interstitial Pneumonia

Lymphocytic interstitial pneumonia (LIP) is a rare lung disease on the spectrum of benign pulmonary lymphoproliferative disorders. LIP is frequently associated with connective tissue diseases or infections. Idiopathic LIP is rare; every attempt must be made to diagnose underlying conditions when LIP is diagnosed. Computed tomography of the chest in patients with LIP may reveal ground-glass opacities, centrilobular and subpleural nodules, and randomly distributed thin-walled cysts. Demonstrating polyclonality with immunohistochemistry is the key to differentiating LIP from lymphoma. The 5-year mortality remains between 33% and 50% and is likely to vary based on the underlying disease process.

The chest X-ray features of chronic respiratory disease in HIV-infected children--a review

Several features of human immunodeficiency virus (HIV) infection contribute to the development of chronic respiratory disease in children. These include the frequency and severity of acute chest infections, as well as the increased risk of pulmonary tuberculosis, aspiration, cardiovascular disease, lymphocytic interstitial pneumonitis or pulmonary neoplasia. The chest radiograph (CXR) remains the most accessible investigation for respiratory disease and plays an important role in the baseline assessment and follow-up. This review focuses on the CXR abnormalities of HIV-related chronic respiratory disease in children. The most commonly documented chronic CXR abnormalities are homogeneous opacification and pulmonary nodules, with pulmonary tuberculosis and lymphocytic interstitial pneumonitis the leading respective causes. Deficiencies in radiographic reporting methodology and relative paucity of radiographic data contribute to current limitations in knowledge and understanding of this field. The review highlights the need for standardised terminology and systematic reporting methodology in future studies. Prospective research on the natural history of lymphocytic interstitial pneumonitis, response to anti-tuberculous therapy, the impact of anti-retroviral therapy and HIV-associated bronchiectasis are needed.

HIV associated Lymphocytic Interstitial Pneumonia: a clinical, histological and radiographic study from an HIV endemic resource-poor setting

Background

There is a paucity of clinical and histopathological data about HIV-associated lymphocytic interstitial pneumonitis (LIP) in adults from HIV endemic settings. The role of Ebstein-Barr virus (EBV) in the pathogenesis remains unclear.

Methods

We reviewed the clinical, radiographic and histopathological features of suspected adult LIP cases at the Groote Schuur Hospital, Cape Town South Africa, over a 6 year period. Archived tissue sections were stained for CD3, CD4, CD8, CD20 and LMP-1 antigen (an EBV marker).

Results

42 cases of suspected LIP(100% HIV-infected) were identified. 75% of patients were empirically treated for TB prior to being referred to the chest service for further investigation. Tissue samples were obtained using trans-bronchial biopsy. 13/42 were classified as definite LIP (lymphocytic infiltrate with no alternative diagnosis), 19/42 probable LIP (lymphocytic infiltrate but evidence of anthracosis or fibrosis) and 10 as non-LIP (alternative histological diagnosis). Those with definite LIP were predominantly young females (85%) with a median CD4 count of 194 (IQR 119–359). Clinical or radiological features had poor predictive value for LIP. Histologically, the lymphocytic infiltrate comprised mainly B cells and CD8 T cells. The frequency of positive EBV LMP-1 antigen staining was similar in definite and non- LIP patients [(2/13 (15%) vs. 3/10 (30%); p = 0.52].

Conclusions

In a HIV endemic setting adult HIV-associated LIP occurs predominantly in young women. The diagnosis can often be made on transbronchial biopsy and is characterized by a predominant CD8 T cell infiltrate. No association with EBV antigen was found.

Noninfectious pulmonary complications of human immunodeficiency virus infection

Human immunodeficiency virus type 1 (HIV-1) is the retrovirus responsible for the development of AIDS. Its profound impact on the immune system leaves the host vulnerable to a wide range of opportunistic infections not seen in individuals with a competent immune system. Pulmonary infections dominated the presentations in the early years of the epidemic, and infectious and noninfectious lung diseases remain the leading causes of morbidity and mortality in persons living with HIV despite the development of effective antiretroviral therapy. In addition to the long known immunosuppression and infection risks, it is becoming increasingly recognized that HIV promotes the risk of noninfectious pulmonary diseases through a number of different mechanisms, including direct tissue toxicity by HIV-related viral proteins and the secondary effects of coinfections. Diseases of the airways, lung parenchyma and the pulmonary vasculature, as well as pulmonary malignancies, are either more frequent in persons living with HIV or have atypical presentations. As the pulmonary infectious complications of HIV are generally well known and have been reviewed extensively, this review will focus on the breadth of noninfectious pulmonary diseases that occur in HIV-infected individuals as these may be more difficult to recognize by general medical physicians and subspecialists caring for this large and uniquely vulnerable population.

The challenge of chronic lung disease in HIV-infected children and adolescents

Until recently, little attention has been given to chronic lung disease (CLD) in HIV-infected children. As the HIV epidemic matures in sub-Saharan Africa, adolescents who acquired HIV by vertical transmission are presenting to health services with chronic diseases. The most common is CLD, which is often debilitating. This review summarizes the limited data available on the epidemiology, pathophysiology, clinical picture, special investigations and management of CLD in HIV-infected adolescents. A number of associated conditions: lymphocytic interstitial pneumonitis, tuberculosis and bronchiectasis are well described. Other pathologies such as HIV-associated bronchiolitis obliterans resulting in non-reversible airway obstruction, has only recently been described. In this field, there are many areas of uncertainty needing urgent research. These areas include the definition of CLD, pathophysiological mechanisms and common pathologies responsible. Very limited data are available to formulate an effective plan of investigation and management.

The overlap of bronchiectasis and immunodeficiency with asthma

Bronchiectasis should be considered as a differential diagnosis for, as well as a comorbidity in, patients with asthma, especially severe or long-standing asthma. Chronic airway inflammation is thought to be the primary cause, as with chronic or recurrent pulmonary infection and autoimmune conditions that involve the airways. Consequently, immunodeficiencies with associated increased susceptibility to respiratory tract infections or chronic inflammatory airways also increase the risk of developing bronchiectasis. Chronic bronchiectasis is associated with impaired mucociliary clearance and increased bronchial secretions, leading to airway obstruction and airflow limitation, which can lead to exacerbation of underlying asthma or increased asthma symptoms.

Undiagnosed HIV Presenting with Lymphoid Interstitial Pneumonitis

Undiagnosed or untreated human immunodeficiency virus infection can lead to devastating complications. We present a case of a 41-year-old woman who was found to have HIV-related lymphoid interstitial pneumonitis. LIP is uncommon, and its presentation can be quite similar to that of other chronic lung conditions. This case illustrates one of the possible protean manifestations of untreated HIV and is a sobering reminder of the need to screen all adults for HIV infection. Additionally, further invasive diagnostic testing may be required to guide therapy in patients with advanced acquired immune deficiency syndrome. This patient's LIP was likely related to long-standing unrecognized HIV disease.

Chest radiographic features of lymphocytic interstitial pneumonitis in HIV-infected children

AIM

To review the radiological features of biopsy-proven lymphocytic interstitial pneumonitis (LIP) in human immunodeficiency virus (HIV)-infected children and establish whether these are based on systematic radiological analysis, and to investigate whether more specific radiological diagnostic criteria can be developed.

MATERIALS AND METHODS

A Medline search of English-language articles on the radiological features of biopsy-proven LIP in HIV-infected children was conducted for the period 1982 to 2007 inclusive. Radiological findings were compared with the Centers for Disease Control and Prevention (CDC) criteria for a presumptive diagnosis of LIP.

RESULTS

Pulmonary pathology was recorded as "diffuse" and "bilateral" in 125 (97.6%) of 128 reported cases of LIP. Twenty-five different terms were used to describe the pulmonary parenchyma. In 96 (75%), the terminology was consistent with CDC diagnostic criteria. Radiological evolution was documented in 43 (33.5%). Persistent focal opacification superimposed on diffuse pulmonary nodularity was demonstrated in 10 (7.8%). The method of radiological evaluation was described in six (4.6%). In no instance was the terminology defined.

CONCLUSION

The radiological features of LIP have not been systematically analysed. However, CDC criteria remain reliable, allowing diagnosis of at least 75% of cases. The sensitivity of these criteria may be increased by including cases with persistent focal pulmonary opacification superimposed on diffuse nodularity. Longitudinal studies utilizing standardized radiographic analysis are needed to elucidate the natural history of LIP.

Chronic lung disease in human immunodeficiency virus (HIV) infected children

The development of chronic lung disease is common in HIV-infected children. The spectrum of chronic HIV-associated lung disease includes lymphocytic interstitial pneumonia (LIP), chronic infections, immune reconstitution inflammatory syndrome (IRIS), bronchiectasis, malignancies, and interstitial pneumonitis. Chronic lung disease may result from recurrent or persistent pneumonia due to bacterial, mycobacterial, viral, fungal or mixed infections. In high tuberculosis (TB) prevalence areas, M. tuberculosis is an important cause of chronic respiratory illness. With increasing availability of highly active antiretroviral therapy (HAART) for children in developing countries, a rise in the incidence of IRIS due to mycobacterial or other infections is being reported. Diagnosis of chronic lung disease is based on chronic symptoms and persistent chest X-ray changes but definitive diagnosis can be difficult as clinical and radiological findings may be non-specific. Distinguishing LIP from miliary TB remains a difficult challenge in HIV-infected children living in high TB prevalence areas. Treatment includes therapy for specific infections, pulmonary clearance techniques, corticosteroids for children with LIP who are hypoxic or who have airway compression from tuberculous nodes and HAART. Children who are taking TB therapy and HAART need adjustments in their drug regimes to minimize drug interactions and ensure efficacy. Preventative strategies include immunization, chemoprophylaxis, and micronutrient supplementation. Early use of HAART may prevent the development of chronic lung disease.

Risk factors for the development of bronchiectasis in HIV-infected children

Our objective was to describe the risk factors for the development of bronchiectasis in HIV-1 infected children. This study was a retrospective, case controlled study based upon medical record review of HIV-1 infected children receiving primary care at a single large, urban medical center in Miami, Florida. Cases (HIV-1 infected children who developed bronchiectasis while being cared for between January 1982 and September 2000) were matched 1:3 (birth +/- 24 months) with controls (HIV-1 infected children without bronchiectasis). Variables analyzed including number of episodes of pneumonia (including Pneumocystis jiroveci pneumonitis [PCP], lymphoid interstitial pneumonitis (LIP), and CDC category of immunosuppression) were noted in both cases and controls until the age at which the cases developed bronchiectasis. Of the 749 patients whose charts were reviewed, 43 met the case definition for bronchiectasis and 19 met the eligibility criteria for this study. Fifty-seven controls were randomly selected from the patients without bronchiectasis. Cases were more likely to have experienced recurrent pneumonia than the controls; 17 (89.5%) versus 5 children (8.8%) respectively (P-value <or=0.001) as well as a greater mean number of episodes of pneumonia 8.2 (range, 4-13) versus 1.45 (range, 0-9) respectively (CI = (5.58,7.82); P-value <or=0.001). Cases were more likely to have progressed to CDC immunological category 3 than the controls; 19 (100%) versus 32 (56%) children respectively (P-value <0.001). LIP occurred more frequently in the cases than in the controls; 14/19 (73.6%) versus 19/57 (33.3%), respectively (P-value = 0.005). HIV-1 infected children with a history of recurrent pneumonia, profound immuno-suppression (CDC immunologic category 3), and LIP appear to have a higher risk of developing bronchiectasis.

Lymphocytic interstitial pneumonitis in HIV infected adults

OBJECTIVES

To describe current knowledge on the aetiology, pathology, presentation, diagnosis, and treatment of lymphocytic interstitial pneumonitis in HIV infected adults.

METHODS

A Medline search was performed using the key words "HIV," "pneumonitis," and "lymphocytes." A further search was performed with the MESH heading "interstitial lung disorders." Related articles were also searched using Pubmed.

RESULTS

Lymphocytic interstitial pneumonitis is a common complication in HIV infected children. In adults it is uncommon and is described most commonly among black African and Afro-Caribbean patients. The aetiology and pathogenesis of lymphocytic interstitial pneumonitis in HIV infection is not clear. The clinical and radiological presentations may be indistinguishable from Pneumocystis carinii infection and a lung biopsy is necessary to establish the diagnosis. Recent evidence suggests that lymphocytic interstitial pneumonitis in HIV infected patients may respond to combination antiretroviral therapy with dramatic improvements in clinical and radiological abnormalities.

CONCLUSION

Lymphocytic interstitial pneumonitis in HIV infected patients is a treatable condition. This condition should be considered in HIV infected patients presenting with respiratory symptoms as they may gain considerable benefit from antiretroviral therapy.

Lymphoid interstitial pneumonia: a narrative review

Lymphoid interstitial pneumonia (LIP) is regarded as both a disease and a nonneoplastic, inflammatory pulmonary reaction to various external stimuli or systemic diseases. It is an uncommon condition with incidence and prevalence rates that are largely unknown. Liebow and Carrington originally classified LIP as an idiopathic interstitial pneumonia in 1969. Although LIP had since been removed from that category, the most recent consensus classification sponsored by the American Thoracic Society and the European Respiratory Society recognizes that some cases remain idiopathic in origin, and its clinical, radiographic, and pathologic features warrant the return of LIP to its original classification among the idiopathic interstitial pneumonias. LIP also belongs within a spectrum of pulmonary lymphoproliferative disorders that range in severity from benign, small, airway-centered cellular aggregates to malignant lymphomas. It is characterized by diffuse hyperplasia of bronchus-associated lymphoid tissue. The dominant microscopic feature of LIP is a diffuse, polyclonal lymphoid cell infiltrate surrounding airways and expanding the lung interstitium. Classically, LIP occurs in association with autoimmune diseases, most often Sjögren syndrome. This has led to consideration of an autoimmune etiology for LIP, but its pathogenesis remains poorly understood. Persons who are seropositive for HIV, and children in particular, are at increased risk of acquiring LIP. Some studies suggest causal roles for both HIV and Epstein-Barr virus. The incidence of LIP is approximately twofold greater in women than men. The average age at diagnosis is between 52 years and 56 years. Symptoms of progressive cough and dyspnea predominate. There is great variability in the clinical course of LIP, from resolution without treatment to progressive respiratory failure and death. Although LIP is often regarded as a steroid-responsive condition, and oral corticosteroids continue to be the mainstay of therapy, response is unpredictable. Approximately 33 to 50% of patients die within 5 years of diagnosis, and approximately 5% of cases of LIP transform to lymphoma.

Bronchial diseases and lung aeration in children

Bronchial diseases are common in children, and are usually associated with disturbances of aeration. This article briefly summarizes the embryological development and respiratory physiology pertinent to pediatric bronchial diseases. Current diagnostic imaging tools are discussed, with an emphasis on CT, which can demonstrate bronchial pathology such as bronchial obstruction and bronchiectasis in larger bronchi, as well as indirectly show the peripheral physiologic consequences of bronchial disease, such as alterations in aeration. Computed tomography measurements of lung attenuation may aid in diagnosis in problematic cases. Diseases that affect the pediatric airways at different ages are reviewed. Knowledge of these entities is important for accurate interpretation of imaging studies.

Follicular bronchiolitis: thin-section CT and histologic findings

PURPOSE

To evaluate the thin-section computed tomographic (CT) findings of follicular bronchiolitis and compare them with the histologic findings.

MATERIALS AND METHODS

Thin-section CT scans obtained in 12 patients (age range, 24-77 years; mean age, 47 years) with follicular bronchiolitis proved at open lung biopsy were reviewed by two observers. Underlying conditions included rheumatoid arthritis (n = 8), mixed collagen vascular disorders (n = 2), autoimmune disorder (n = 1), and acquired immunodeficiency syndrome (n = 1). All patients had thin-section CT scans (1.0-1.5-mm collimation, 11 patients; 3.0-mm collimation, one patient; high-spatial-frequency reconstruction algorithm) obtained at 10-mm intervals through the chest.

RESULTS

The main CT findings included bilateral centrilobular (n = 12) and peribronchial (n = 5) nodules. All 12 patients had nodules smaller than 3 mm in diameter; six patients also had nodules 3-12 mm in diameter. Areas of ground-glass opacity were present in nine (75%) patients. Histologically, all patients had lymphoid hyperplasia along the bronchioles; eight had peribronchiolar lymphocytic infiltration.

CONCLUSION

The cardinal CT feature of follicular bronchiolitis consists of small centrilobular nodules variably associated with peribronchial nodules and areas of ground-glass opacity.

Chest imaging in AIDS

A review of imaging in the acquired immune deficiency syndrome (AIDS) is presented. The imaging features can be conveniently categorized according to whether the presenting complications are infective (bacterial, protozoal, or fungal), bronchiectasis, neoplastic (Kaposi's sarcoma, AIDS-related lymphoma, or lymphoproliferative disease), or a miscellaneous group (non-specific interstitial pneumonitis, persistent generalized lymphadenopathy, or bronchogenic carcinoma).

Bronchiectasis in pediatric AIDS

OBJECTIVES

There are several reports of the pulmonary findings in children with HIV disease; however, the occurrence of bronchiectasis rarely has been noted. We evaluated occurrence of bronchiectasis in a large group of children referred to us with AIDS pneumopathy.

METHODS

From January 1984 to April 1996, 203 children with AIDS and respiratory problems were referred to the pediatric pulmonary division at Children's Medical Center of Brooklyn. Medical records for 164 of these children were available and retrospectively reviewed.

RESULTS

Uncomplicated pneumonia was present in 75, 24 had recurrent pneumonia, and 18 had unresolved pneumonia; lymphocytic interstitial pneumonitis (LIP) was diagnosed in 47 patients, worsening with time in all patients. Bronchiectasis was observed in 26 patients (26/164, 15.8%), diagnosed by chest radiograph in 26 (26/26, 100%), confirmed by CT scan of chest in 10 (10/26, 38.4%), and by histology in three (3/26, 11.5%). Median age at time of diagnosis of bronchiectasis was 7.5 years (range, 1 to 16 years). Sixteen children with LIP developed bronchiectasis (16/47, 34.0%). Three patients with recurrent pneumonia (3/24, 12.5%) developed bronchiectasis. Five patients with unresolved pneumonia (5/18, 27.7%) developed bronchiectasis. One infant developed bronchiectasis after Pneumocystis carinii pneumonia; another child developed bronchiectasis after P. carinii and Mycobacterium tuberculosis pneumonia. The CD4+ T-cell counts measured within 6 months of diagnosis of bronchiectasis were available in 23/26 patients and, all were < 100 cells per cubic millimeter.

CONCLUSION

We conclude, from our experience, that there is a significant occurrence of bronchiectasis in children with AIDS and pulmonary disease, especially in children developing LIP, recurrent pneumonia and unresolved pneumonia, and CD4+ T-cell counts < 100 cells per cubic millimeter.

Chest high resolution CT in adults with primary humoral immunodeficiency

The purpose of this study was to assess the findings on chest high resolution computed tomography (HRCT) in patients with primary humoral immunodeficiency. HRCT was prospectively and consecutively performed in 19 patients with primary humoral immunodeficiency, aged 15-64 years (mean 36), and in 15 healthy subjects. HRCT results were correlated with clinical and biological data. Bronchial lesions were observed in 11 patients (58%), consisting either of bronchial wall thickening in eight or bronchiectasis in eight; both were present in five patients. Lobar and/or segmental collapses were found in seven patients (37%), scars in eight patients (42%), interstitial lesions in six patients (32%), and lobular air-trapping in two patients (11%). Parenchymal collapses were correlated with the annual frequency of infections (p = 0.03) and with the IgA level (p = 0.01). Scars were correlated with the annual frequency of infections (p = 0.04). No correlation was found between bronchial wall thickening or bronchiectasis and the data analysed. In conclusion, HRCT is a useful method to demonstrate lung disease in primary humoral immunodeficiencies, with special emphasis on bronchial changes and interstitial lesions.

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.

Bronchiectasis due to lipid aspiration in childhood: clinical and pathological correlates

We report the clinical and pathological features in six Arab children with bronchiectasis caused by ghee lipid aspiration. They all had a history of ghee administration followed by a history of chronic cough dating from early childhood. Chest radiographs showed consolidation/collapse of the right middle and left lower lobes in the majority, and bronchography and chest CT scan confirmed bronchiectasis. The children were treated medically, without any improvement, and five required surgery. The histology of the lung revealed dilated bronchi filled with vacuolated granular eosinophilic material and the peripheral lung tissue was mostly atelectatic with patchy lymphocytic bronchiolitis. Frozen sections of the lung tissue showed scattered lipogranulomas with fat-laden macrophages and fat droplets within peripheral and perivascular lymphatics. In communities where the traditional practice of force-feeding infants and children with ghee exists, it may be an important predisposing cause of bronchiectasis.

Pneumothorax as the presenting sign of Pneumocystis carinii infection in an HIV-positive child with prior lymphocytic interstitial pneumonitis

An HIV-positive child presented with a pneumothorax secondary to cavitary Pneumocystis carinii pneumonia (PCP). Lymphocytic interstitial pneumonitis had been evident on earlier radiographs but had resolved, concurrent with a decrease in her CD4 counts, before the radiographic changes of PCP became evident. As immune function declines in HIV-positive children, the chest radiograph may paradoxically clear. In such a setting, development of focal lung disease, including pneumothorax, may herald Pneumocystis carinii infection.

Application of thin-section low-dose chest CT (TSCT) in the management of pediatric AIDS

The aim of this study was to evaluate the usefulness of thin-section low-dose computed tomography (TSCT) in the management of children with AIDS, as chest radiographs (CXR) often fail to adequately explain the patients' clinical status. We performed 54 noncontrast TSCTs on 32 children. The patients aged from 3 months to 14.6 years, were diagnosed as having bacterial pneumonia, lumphocytic interstitial pneumonitis (LIP), Pneumocystis carinii pneumonia (PCP), or Mycobacterium avium-intracellulare infection (MAI). The scans were correlated with the clinical diagnosis, T-lymphocyte-subset percentages, and p24-antigen levels. Subsegmental consolidations were seen in patients with LIP, PCP, and MAI, and as an isolated finding in those with only bacterial pneumonia. Ground-glass haziness was seen exclusively with acute PCP. Reticulonodular thickening was identified only in patients with LIP. Mosaic perfusion was seen with MAI, LIP, and pneumonia. The presence of adenopathy correlated with CD4+ T-cell subset percentages. The greatest value of CT in this study was in detecting new disease when chest films failed to correlate with a patient's clinical state, and in demonstrating acute/subacute disease in patients with severe baseline chest-film changes. Recurrent pneumonias may represent progression of "smoldering" disease, rather than true recurrent disease following complete clearing. Adenopathy with low CD4+ levels should suggest lymphoma or infection with MAI.

Pediatric HIV infection: an imaging update

Infection with the human immunodeficiency virus (HIV) can produce a broad range of illness, including opportunistic infections, lymphoproliferative diseases, and benign and malignant neoplasms. Each conditions has its own spectrum of imaging findings. This paper will highlight those findings in children suffering from HIV infection/AIDS. We will stress the findings in the more frequently involved organ systems and those that are unique to children.