Chest high resolution CT in adults with primary humoral immunodeficiency

Evaluation of pulmonary findings in patients with humoral immunodeficiency

Aim:

To determine the frequency of sinopulmonary infections, detect changes in the respiratory system, and measure functional capacity of the lungs in our patients with humoral immunodeficiency.

Material and Methods:

Fifty-six patients with humoral immunodeficiency were enrolled in this study. The clinical, laboratory, and radiologic data, and pulmonary function tests of the subjects were evaluated from their file records, retrospectively.

Results:

The distribution of our patients was as follows: 25 patients had common variable immune deficiency, three patients had X-linked agammaglobulinemia, five patients had hyper immunoglobulin M syndrome, 19 patients had deficiency of immunoglobulin G subset, and four patients had selective immunoglobulin A deficiency. The most common symptom of the patients was chronic cough (n=47, 83.9%). The most common pathologies on high-resolution computed tomography of the chest were atelectasis and bronchiectasis (27.7%). The most common pathology in pulmonary function tests was the presence of moderate obstructive patterns along with restrictive patterns (n=6,12.5%). The FEV 1, FVC, and FEF 25–75 values were significantly lower in patients with common variable immunodeficiency compared with the patients who had IgG subset deficiencies (p=0.001, p=0.01, p=0.01). Among the patients who were treated with intravenous immunoglobulin, the age at the diagnosis of immunodeficiency was higher in patients with bronchiectasis (14.2±8.4 years) compared with those without bronchiectasis (10.1±11.4 years) (p=0.04).

Conclusion:

Clinical findings are not sufficient to monitor the structural and functional changes in the respiratory system, and patients should be evaluated using high-resolution computed tomography of the chest and pulmonary function tests.

[Pulmonary manifestations in adult patients with a defect in humoral immunity]

Primary immunodeficiencies (PIDs) are a group of congenital diseases of the immune system, which numbers more than 230 nosological entities associated with lost, decreased, or wrong function of its one or several components. Due to the common misconception that these are extremely rare diseases that occur only in children and lead to their death at an early age, PIDs are frequently ruled out by physicians of related specialties from the range of differential diagnosis. The most common forms of PIDs, such as humoral immunity defects, common variable immune deficiency, X-linked agammaglobulinemia, selective IgA deficiency, etc., are milder than other forms of PID, enabling patients to attain their adult age, and may even manifest in adulthood. Bronchopulmonary involvements are the most common manifestations of the disease in patients with a defect in humoral immunity. Thus, a therapist and a pulmonologist are mostly the first doctors who begin to treat these patients and play a key role in their fate, since only timely diagnosis and initiation of adequate therapy can preserve not only the patient's life, but also its quality, avoiding irreversible complications. Chest computed tomography changes play a large role in diagnosis. These are not specific for PID; however, there are a number of characteristic signs that permit this diagnosis to be presumed.

Expiratory air trapping on thoracic computed tomography. A diagnostic subclassification

RATIONALE

Multiple causes for air trapping as identified by expiratory computed tomography (CT) have been reported, but a unified evaluation schema has never been proposed.

OBJECTIVES

It was our purpose to identify imaging features that would help distinguish etiologies of mosaic air trapping.

METHODS

Cases with the term "air trapping" in the radiology report in 2010 were identified by searching the Radiology Information System of an academic tertiary care center and associated community hospital. Medical records and CT examinations were reviewed for the causes of air trapping.

MEASUREMENTS AND MAIN RESULTS

Causes for moderate to severe air trapping could be identified in 201 of 230 (87.4%) cases and could be subdivided into those associated with bronchiectasis (76 of 201, 38%), those associated with interstitial lung disease (62 of 201, 31%), those associated with tree-in-bud opacities (5 of 201, 2%), and those with air trapping alone (58 of 201, 29%). When found with bronchiectasis, nontuberculous mycobacteria, cystic fibrosis, idiopathic bronchiectasis, and transplant-related bronchiolitis obliterans were the most common causes of air trapping. When found with interstitial lung disease, sarcoidosis, hypersensitivity pneumonitis, or unspecified interstitial lung disease were the most common cause of air trapping. When found in isolation, chronic bronchitis, asthma, bronchiolitis obliterans, and unspecified small airways disease were the most common causes of air trapping. Unusual conditions causing isolated air trapping included vasculitis and diffuse idiopathic neuroendocrine cell hyperplasia.

CONCLUSION

A variety of conditions can cause air trapping. Associated imaging findings can narrow the differential diagnosis.

Does increasing immunoglobulin levels impact survival in solid organ transplant recipients with hypogammaglobulinemia?

BACKGROUND

Severe hypogammaglobulinemia (IgG < 400 mg/dL) has adverse impact on mortality during the first year post-transplantation. The aim of the study was to determine whether increasing IgG levels to ≥400 mg/dL improved outcomes.

METHODS

Kaplan-Meier analyses were performed to estimate survival, log-rank test to compare survival distributions between groups, and Fisher's exact test to determine the association between hypogammaglobulinemia and rejection or graft loss.

RESULTS

Thirty-seven solid organ transplant (SOT) recipients were included. Hypogammaglobulinemia was diagnosed at median of 5.6 months (range: 0-291.8 months) post-transplantation. Types of transplants: liver-small bowel (17); liver-small bowel-kidney (2); liver (5); small bowel (4); liver-kidney (1); kidney/kidney-pancreas (3); heart (3); heart-kidney (1); and heart-lung (1). The three-yr survival after the diagnosis of hypogammaglobulinemia was 49.5% (95% CI: 32.2-64.6%). Patients were dichotomized based upon IgG level at last follow-up: IgG ≥ 400 mg/dL (23 patients) and IgG < 400 mg/dL (14 patients). There was no evidence of a difference in survival (p = 0.44), rejection rate (p = 0.44), and graft loss censored for death (p = 0.99) at one yr between these two groups. There was no difference in survival between patients receiving or not immunoglobulin (p = 0.99) or cytomegalovirus hyperimmunoglobulin (p = 0.14).

CONCLUSION

Severe hypogammaglobulinemia after SOT is associated with high mortality rates, but increasing IgG levels to ≥400 mg/dL did not seem to translate in better patient or graft survival in this cohort.

Pulmonary manifestations of primary immunodeficiency disorders in children

Primary immunodeficiencies (PIDs) are inherited disorders in which one or several components of immune system are decreased, missing, or of non-appropriate function. These diseases affect the development, function, or morphology of the immune system. The group of PID comprises more than 200 different disorders and syndromes and the number of newly recognized and revealed deficiencies is still increasing. Their clinical presentation and complications depend on the type of defects and there is a great variability in the relationship between genotypes and phenotypes. A variation of clinical presentation across various age categories is also presented and children could widely differ from adult patients with PID. Respiratory symptoms and complications present a significant cause of morbidity and also mortality among patients suffering from different forms of PIDs and they are observed both in children and adults. They can affect primarily either upper airways (e.g., sinusitis and otitis media) or lower respiratory tract [e.g., pneumonia, bronchitis, bronchiectasis, and interstitial lung diseases (ILDs)]. The complications from lower respiratory tract are usually considered to be more important and also more specific for PIDs and they determinate patients' prognosis. The spectrum of the causal pathogens usually demonstrates typical pattern characteristic for each PID category. The respiratory signs of PIDs can be divided into infectious (upper and lower respiratory tract infections and complications) and non-infectious (ILDs, bronchial abnormalities - especially bronchiectasis, malignancies, and benign lymphoproliferation). Early diagnosis and appropriate therapy can prevent or at least slow down the development and course of respiratory complications of PIDs.

Respiratory disease in common variable immunodeficiency and other primary immunodeficiency disorders

Respiratory disease is a significant cause of morbidity and mortality amongst patients with primary immunodeficiency disorders. Computed tomography (CT) plays an important role in the multidisciplinary approach to these conditions, in detecting, characterizing, and quantifying the extent of lung damage and in directing treatment. The aim of this review is to classify the primary immunodeficiency disorders and describe the thoracic complications and the associated CT findings whilst discussing the role of radiology in diagnosis and surveillance.

Airway and interstitial lung disease are distinct entities in paediatric common variable immunodeficiency

Common variable immunodeficiency (CVID) is a common primary immune deficiency, caused by undefined defects in lymphocyte function, and is treated routinely by immunoglobulin substitution. CVID complications include airway disease (AD) and interstitial lung disease (ILD). It was not known if AD and ILD in CVID have a common immunological aetiology and should be considered separate features of the same disease, or as distinct syndromes that require specialized monitoring and treatment. We used high-resolution computed tomography (CT) to diagnose AD or ILD in paediatric CVID patients. Spirometry and body plethysmography did not differentiate between ILD and AD. Patients with AD (n = 11, 20%) developed more pneumonias while children with ILD (n = 8, 15%) showed immune dysregulation characterized by autoimmune complications, more severe memory B cell reduction and expansion of non-naive cytotoxic T cells. In conclusion, ILD and AD in CVID have dissimilar clinical and immunological characteristics, suggesting distinct aetiology requiring tailored monitoring and treatment of these patient subgroups.

Detection of pulmonary complications in common variable immunodeficiency

Touw CML, van de Ven AA, de Jong PA, Terheggen-Lagro S, Beek E, Sanders EAM, van Montfrans JM. Detection of pulmonary complications in common variable immunodeficiency. Pediatr Allergy Immunol 2010: 21: 793-805. (c) 2009 John Wiley & Sons A/S Pulmonary complications are frequently observed in common variable immunodeficiency (CVID). We reviewed the literature related to radiologic imaging techniques and pulmonary function tests (PFT) for diagnosing pulmonary complications in CVID. Scientific publications related to CVID (or primary hypogammaglobulinemia), pulmonary complications, PFT, chest X-ray (CXR), and high-resolution computed tomography scan (HRCT) were detected in PubMed, Embase and in reference lists of selected articles. Twenty-six articles including 1047 patients (587 patients with CVID) were reviewed. Up to 73% of CVID patients develop chronic structural pulmonary complications, of which bronchiectasis and bronchial wall thickening are most frequently detected. HRCT is the most sensitive method for identification of structural abnormalities, detecting pulmonary complications that were missed on CXR and PFT in 2-59% of patients. On PFT, obstructive flow-volume curves were most commonly found, eventually occurring in 50-94% of patients. HRCT is an important diagnostic tool for pulmonary complications in CVID at the time of diagnosis and at regular time-points during follow-up, with the proper follow-up interval yet to be determined.

Development of pulmonary abnormalities in patients with common variable immunodeficiency: associations with clinical and immunologic factors

BACKGROUND

Patients with common variable immunodeficiency (CVID) have low serum IgG, IgA, and/or IgM levels and recurrent airway infections. Radiologic pulmonary abnormalities and impaired function are common complications. It is unclear to what extent IgG replacement treatment prevents further pulmonary damage and how factors beside infections may contribute to progression of disease.

OBJECTIVES

To study the development of pulmonary damage and determine how clinical and immunologic factors, such as serum IgG, may contribute to possible changes.

METHODS

In a retrospective, longitudinal study of 54 patients with CVID already treated with immunoglobulins, we examined changes of lung function and findings on high-resolution computed tomography (HRCT), obtained at 2 time points (the date of the last pulmonary function measurement before April 2005 [T1] and the date of the measurement performed closest to 5 years earlier [T0]) 2 to 7 years apart and explored possible relations to clinical and immunologic factors such as levels of IgG, tumor necrosis alpha (TNF-alpha), and mannose-binding lectin (MBL) in serum.

RESULTS

Despite a mean (SD) serum IgG level of 7.6 (2.3) g/L for all the patients during the entire study period, lung function decreased from T0 to T1. The combination of a low serum IgA level and serum MBL was associated with the presence of bronchiectasis and lower lung function and with worsening of several HRCT abnormalities from T0 to T1. Increased serum levels of TNF-alpha were related to deterioration of gas diffusion. A mean serum IgG level less than 5 g/L between T0 and T1 was associated with worsening of linear and/or irregular opacities seen on HRCT.

CONCLUSION

For a period of 4 years, lung function and HRCT deteriorated in CVID patients treated with immunoglobulins.

Echocardiographic abnormalities and their correlation with bronchiectasis score in primary antibody deficiencies

BACKGROUND

Primary antibody deficiencies are characterized by defective antibody production and recurrent infections. Patients usually present with recurrent respiratory tract infections with consequent chronic pulmonary damage and bronchiectasis, which could potentially influence cardiac function. Our aim was to assess noninvasively the cardiac complications due to pulmonary disease in patients with primary antibody deficiency.

METHODS

A cross-sectional series of patients with primary antibody deficiency syndromes from our referral immunology center were recruited. Individuals undergoing high-resolution computed tomography (HRCT) and transthoracic echocardiography were reviewed.

RESULTS

Thirty primary immunodeficient patients aged 5-55 years of age (21 males and 9 females) were enrolled in this study. Half of the patients (50%) were found to have bronchiectasis in HRCT imaging. In echocardiographic examination, 20 patients (67%) had at least one abnormality; among which pulmonary hypertension was the most common (33%). Patients with bronchiectasis had higher pulmonary artery pressures and HRCT bronchiectasis score was strongly correlated with pulmonary artery pressure (regression R = 0.59, P value = 0.001).

CONCLUSION

Echocardiographic evaluation of right ventricular function and noninvasive estimation of pulmonary artery pressure could have an important diagnostic role in the follow-up and therapeutic management of patients with primary immune deficiency.

Common variable immunodeficiency: an update on therapeutic approaches

Common variable immunodeficiency (CVID) is not a homogeneous disease, as has become clear from recent scientific studies. This makes the interpretation of studies of clinical therapeutics difficult to assess and raises questions about historical case reports. The evidence for the optimum use of replacement immunoglobulin in CVID is reviewed. This therapy represents the current gold standard, despite attempts to use other immunostimulatory compounds. Questions of product properties, product selection, adverse events and infectious risks are addressed. Products are not interchangeable and have different physicochemical characteristics. Despite intravenous immunoglobulin being in use for 20 years, there are still unanswered questions over dose and target trough IgG levels, particularly with respect to patients with established lung disease. The management of organ-based complications of CVID is discussed. This includes the treatment of unusual infections such as mycoplasmas and enteroviruses, which are specific to antibody deficiency. The diagnosis and treatment of the granulomatous disease of CVID is discussed. The role of surgery, including lung transplantation, in the management of CVID complications is reviewed. There are few available data on optimum strategies for antibiotic usage for bacterial infective complications and it is clear that present regimens, at least in severe recurrent sinus disease, are not consistently effective. Better clinical trials are required to identify appropriate regimens and validate or disprove widely held assumptions about therapy in CVID. Despite advances in diagnosis and management, there is abundant evidence in the UK that patients do not yet receive rapid diagnosis and optimum therapy, even within the limited published data currently available. This leads to considerable avoidable morbidity and mortality.

Thoracic manifestations of primary humoral immunodeficiency: a comprehensive review

Humoral immunodeficiencies, which are characterized by defective production of antibodies, are the most common types of primary immunodeficiency. Pulmonary changes are present in as many as 60% of patients with humoral immunodeficiency. Chronic changes and recurrent infections in the respiratory airways are the main causes of morbidity and mortality in those affected by a humoral immunodeficiency. Medical imaging, especially computed tomography (CT), plays a crucial role in the initial detection and characterization of changes and in monitoring the response to therapy. The spectrum of abnormalities seen at thoracic imaging includes noninfectious airway disorders, infections, chronic lung diseases, chronic inflammatory conditions (granulomatosis, interstitial pneumonias), and benign and malignant neoplasms. Recognition of characteristic CT and radiographic features, and correlation of those features with clinical and laboratory findings, are necessary to differentiate between the many possible causes of parenchymal and mediastinal disease seen in patients with primary humoral immunodeficiencies.

Granulomatous-lymphocytic interstitial lung disease associated with common variable immunodeficiency: CT findings

PURPOSE

To evaluate computed tomography (CT) scans of individuals with granulomatous-lymphocytic interstitial lung disease and common variable immunodeficiency (CVID) to determine if there are imaging features that distinguish this manifestation of CVID from the more usual imaging findings.

MATERIALS AND METHODS

A review of the CVID population at our institution identified a series of 5 patients with CVID who had documented granulomatous disease on biopsy specimens. The initial and follow-up CT examinations were reviewed by 2 radiologists, and imaging findings in the chest and abdomen were tabulated by consensus. In addition, a pathologist reviewed histopathologic specimens and clinical presentations and therapeutic interventions were obtained from patient charts.

RESULTS

In all, 5/5 patients (100%) had widespread pulmonary micronodules with a lower lung zone predominance, 4/5 (80%) had smooth interlobular septal thickening with mid to lower lung zone predominance, 1/5 (20%) had mild bronchiectasis, 4/5 (80%) had multifocal pulmonary consolidation, 5/5 (100%) had thoracic or abdominal lymphadenopathy, 2/5 (40%) had hepatomegaly, 5/5 (100%) had splenomegaly, 1/5 (20%) had nonspecific hypoattenuating splenic lesions, and 2/5 (40%) had nonspecific hypoattenuating renal lesions. The pulmonary nodules and lymphadenopathy commonly tended to wax and wane in severity over time, and more marked disease was often associated with areas of focal consolidation.

CONCLUSION

Granulomatous-lymphocytic interstitial lung disease, which can occur in patients with CVID, presents with CT findings distinct from the usual airway abnormalities most commonly associated with CVID.

Clinical immunology review series: An approach to the management of pulmonary disease in primary antibody deficiency

The sinopulmonary tract is the major site of infection in patients with primary antibody deficiency syndromes, and structural lung damage arising from repeated sepsis is a major determinant of morbidity and mortality. Patients with common variable immunodeficiency may, in addition, develop inflammatory lung disease, often associated with multi-system granulomatous disease. This review discusses the presentation and management of lung disease in patients with primary antibody deficiency.

High resolution computed tomography and pulmonary function in common variable immunodeficiency

Patients with common variable immunodeficiency (CVID) have impaired production of immunoglobulins and hence recurrent airway infections, which in turn may lead to radiological changes and impaired lung function. Uncertainty exists about the nature and frequency of the radiological and the physiological abnormalities, and how they relate to each other. We reassessed high resolution computed tomography (HRCT) images in 65 patients, reported results from previously measured lung function tests, and studied relations between radiology, function and clinical variables. Airway obstruction, ventilatory restriction and impaired gas diffusion was found in 40, 34 and 21% of the patients, respectively. HRCT abnormalities were present in 94% of the subjects, mild changes being the most common. Bronchial wall thickening, found in two thirds of the patients, was related to airway obstruction and impaired gas diffusion. Linear and/or irregular opacities, the most frequent interstitial abnormality, was related to impaired gas diffusion. Bronchiectasis was found in more than half, but only severe bronchiectasis was related to airway obstruction. Since bronchial wall thickening and linear and/or irregular opacities are both frequent and important determinants of impaired pulmonary function, more attention should be given to these features in the follow up of CVID patients.

Genetic causes of bronchiectasis: primary immune deficiencies and the lung

Primary immune deficiencies (PID) comprise a heterogeneous group of genetically determined disorders that affect development and/or function of innate or adaptive immunity. Consequently, patients with PID suffer from recurrent and/or severe infections that frequently involve the lung. While the nature of the immune defect often dictates the type of pathogens that may cause lung infection, there is substantial overlap of radiological findings, so that appropriate laboratory tests are mandatory to define the nature of the immune defect and to prompt appropriate treatment. At the same time, the recent identification of a large number of PID-causing genes now allows early, even presymptomatic diagnosis, thus representing an essential tool for prevention of lung damage. This review article describes the most common forms of PID, their cellular and molecular bases, and the associated lung abnormalities, and reports on available treatment.

Recognition, clinical diagnosis and management of patients with primary antibody deficiencies: a systematic review

The primary purpose of this systematic review was to produce an evidence-based review of the literature as a means of informing current clinical practice in the recognition, diagnosis and management of patients with suspected primary antibody deficiency. Randomized controlled trials (RCTs) were identified from a search of MEDLINE, EMBASE, The Cochrane Library, DARE (CRD website) and CINAHL by combining the search strategies with The Cochrane Collaboration's validated RCT filter. In addition, other types of studies were identified in a separate search of MEDLINE and EMBASE. Patients at any age with recurrent infections, especially in the upper and lower respiratory tracts, should be investigated for possible antibody deficiency. Replacement therapy with immunoglobulin in primary antibody deficiencies increases life expectancy and reduces infection frequency and severity. Higher doses of immunoglobulin are associated with reduced infection frequency. Late diagnosis and delayed institution of immunoglobulin replacement therapy results in increased morbidity and mortality. A wide variety of organ-specific complications can occur in primary antibody deficiency syndromes, including respiratory, gastroenterological, hepatic, haematological, neurological, rheumatological and cutaneous. There is an increased risk of malignancy. Some of these complications appear to be related to diagnostic delay and inadequate therapy. High-quality controlled trial data on the therapy of these complications is generally lacking. The present study has identified a number of key areas for further research, but RCT data, while desirable, is not always obtained easily for rare conditions. Few data from registries or large case-series have been published in the past 5 years and a greater focus on international collaboration and pooling of data is needed.

Lung diseases in patients with common variable immunodeficiency: chest radiographic, and computed tomographic findings

OBJECTIVE

To evaluate chest radiographic and computed tomographic (CT) findings of lung disease related to common variable immunodeficiency.

METHODS

Thirty-five chest radiographs and 30 CT scans of 46 patients were assessed. Lung parenchymal abnormalities that were evaluated included airspace consolidation, ground-glass attenuation, nodules, bronchiectasis, and air trapping.

RESULTS

On CT, ground-glass attenuation and nodules were the most frequent findings, observed in 60% (n = 18/30) and 83% (n = 25/30), respectively. Three major CT patterns were identified: airway disease (n = 13), nodules (n = 8), and parenchymal opacification (n = 6). All 13 patients with airway disease showed centrilobular opacities. One patient with peribronchial nodules showed lymphoid interstitial pneumonia, and 1 with randomly distributed nodules showed noncaseating granulomas. Patients with a CT pattern of parenchymal opacification showed lower lung predominance; surgical biopsies showed organizing pneumonia in 1 patient and lymphoid interstitial pneumonia with nonnecrotizing granulomas in another.

CONCLUSIONS

Common variable immunodeficiency is associated with 3 major CT patterns: airway disease, nodules, and parenchymal opacification.

The HRCT appearances of granulomatous pulmonary disease in common variable immune deficiency

Approximately 10% of patients with common variable immune deficiency have systemic granulomatous disease with associated interstitial lung disease. From a population of patients with CVID attending a large tertiary referral clinic for primary immunodeficiency diseases we selected a cohort who had a restrictive defect or impaired gas transfer on pulmonary function testing and/or histologically proven granulomatous disease. HRCT scans of the thorax were reviewed retrospectively in 18 patients by two radiologists. Thirteen patients had diffuse reticulation, which varied from fine to coarse with features of fibrosis. Nodules were found in eight patients. In seven, these were associated with reticulation and in one they were an isolated finding. Bronchiectasis was found as the only abnormality in three and in addition to diffuse reticulation or nodules in another three patients. Greater appreciation of the spectrum of the radiological abnormalities in CVID patients with interstitial lung disease is important. Deteriorating lung function in patients with granulomatous CVID may be secondary to interstitial lung disease rather than bronchiectasis, and treatment should be tailored accordingly.

[Etiological work-up for bronchectasia in adults]

Search for an etiology of bronchiectasis consists in identifying constitutional or acquired defense mechanisms of the respiratory mucosa. The question is timely because causes change. In developing countries, presumed sequelae of infection account for about 30% of the cases despite vaccination campaigns, control of endemic tuberculosis, and widespread use of antibiotics. Genetic diseases account for 20% of the causes when identified by high-performance prospective diagnostic tests (CFTR mutation). Computed tomography enables the identification of frequent associations between bronchiectasis and rheumatoid disease or ulcerative colitis. Recent diseases such as HIV infection or GVHD can also lead to bronchiectasis. Nevertheless, the cause remains unknown in 30-50% of patients. After a detailed analysis of the clinical presentation and diagnostic criteria specific for each etiology, we propose a two-phase diagnostic procedure. The first step, used for all patients (careful history taking, physical examination, imaging, bronchofibroscopy, limited blood tests) enables detecting localized bronchial obstacles and obvious etiologies (situs inversus of primary ciliary dyskinesia, known systemic disease, HIV...). If the first step is negative, the second phase is oriented by the clinical context. Sequelae of infection (tuberculosis...) in older subjects or migrants, a genetic cause in younger subjects, particularly if there is a familial history and/or infertility, a systemic disease or allergic bronchopulmonary aspergillosis if there is an extra-respiratory context. This etiological search should help improve patient management and provide a better prognosis and prevention of bronchiectasis.

Pulmonary interstitial disease in Ig deficiency

STUDY OBJECTIVES

To determine the frequency and type of interstitial lung disease (ILD) in consecutive subjects with symptomatic Ig deficiency.

PATIENTS

One hundred forty-eight consecutive subjects with repeated respiratory infections and Ig deficiency.

MEASUREMENTS

Ig classes and IgG subclasses (IgGSCs), the response to vaccination, pulmonary function tests, chest radiography, CT scan, Ga scan and, when possible, BAL and lung biopsy.

RESULTS

Twenty-nine of 148 subjects (19 men and 10 women aged 18 to 72 years) had evidence of ILD. In 20 subjects, no cause of ILD was apparent. The remaining nine cases were ostensibly due to identifiable causes. Twenty subjects had IgGSC deficiency, 8 subjects had common variable immunodeficiency, and 1 subject had combined IgM plus IgGSC deficiency. No isotype deficiency was consistently related to a specific ILD. After administration of IV Ig, eight subjects, all with IgGSC deficiency, improved clinically, physiologically, radiologically, and occasionally histologically, regardless of immunologic or radiologic features. In this selective sample, the prevalence of ILD in consecutive subjects with recurrent respiratory infections and Ig deficiency (29 of 148 subjects; 19.6%) was higher than in the general population (0.8%; p < 0.05).

CONCLUSIONS

ILD in Ig deficiency is frequent and usually involves IgGSC deficiency.