Lymphocytic bronchiolitis

BALT in normal man is sparse, but a striking reactive lymphoid proliferation can occur in disease. These hyperplastic changes can differ in extent and location within the lung. This is the case in reactive lesions such as follicular bronchiolitis, lymphocytic interstitial pneumonia (LIP), and nodular lymphoid hyperplasia (NLH). 

Chatte, G., Streichenberger, N., Boillot, O., Gille, D., Loire, R., Gordie, J.F. Lymphocytic bronchitis/bronchiolitis in a patient with primary biliary cirrhosis. Eur. Respir. J. 1995 8 176-179... 

Late pulmonary complications cover a wide spectrum of disorders and include both obstructive and restrictive lung diseases. Included in these disorders are bronchiolitis obliterans with or without organizing pneumonia, diffuse alveolar damage, and lymphocytic interstitial pneumonia. 9,80 xjjgj- py consists of steroids, which are... 

Holland VA, Cagle PT, Windsor NT, Noon GP, Greenberg SD, Lawrence EC. Lymphocyte subset populations in bronchiolitis obliterans after heart-lung transplantation. Transplantation 1990 50 955-959. 

In the lungs of rats exposed to cigarette smoke, Chang et al. (2001) found the terminal bronchioles infiltrated predominantly with lymphocytes in the peribronchiolar region and a mild moderate degree of emphysema in the alveolar spaces. The terminal bronchioles also showed marked lipid peroxidation, dilatation, and peribronchiolar fibrosis. 

Usual interstitial pneumonia Nonspecific interstitial pneumonia Organizing pneumonia Diffuse alveolar damage Respiratory bronchiolitis Desquamative interstitial pneumonia Lymphocytic interstitial pneumonia Idiopathic pulmonary fibrosis/cryptogenic fibrosing alveolitis Nonspecific interstitial pneumonia (provisional) Cryptogenic organizing pneumonia Acute interstitial pneumonia Respiratory bronchiolitis-associated interstitial lung disease Desquamative interstitial pneumonia Lymphocytic interstitial pneumonia... 

Sjogren syndrome (SS) is characterized by infiltration of CD4-positive lymphocytes into different organs, most notably the lacrimal and salivary glands. In the lung, the disease manifests as a prominent lymphoreticular infiltration in the tracheobronchial tree with follicular bronchiolitis, atrophy of glands, and fibrosis... 

Exposure to elevated concentrations of beryllium, usually in the 25 pg/m range or greater, (120) can result in inflammation of the upper and lower respiratory tract and airways, tracheitis, bronchiolitis, pulmonary edema, and a lymphocyte-predominant chemical pneumonitis (12,121-123). Although significantly less common than CBD, acute beryllium disease stiU occurs globally. In 2004, nine cases were reported from a South Korean liquid metal factory where measured beryllium exposures ranged from 3.13 to 112.3 pg/m (12). The manifestations... 

Table 2 Differential Diagnosis of Nodular Lymphoid Hyperplasia (NLH), Lymphocytic Interstitial Pneumonia (LIP), Follicular Bronchiolitis (FB), and Extranodal Marginal Zone Lymphoma (Maltoma)... 

LIP and hypersensitivity pneumonitis (extrinsic allergic alveolitis) may be difficult to distinguish. Radiographically, both show bilateral infiltrates. Microscopically, hypersensitivity pnemnonitis may resemble LIP in showing interstitial lymphocytic infiltrates containing ill-formed granulomas. Hypersensitivity pneumonitis has a patchier (airway-centered) and milder interstitial pneumonitis, and it can show bronchiolitis obliterans, a feature not seen in LIP. 

Glandular and extra-glandular lymphocytic infiltration of the lung finds expression in a continuum from benign to malignant disease (from follicular bronchiolitis to LIP to lymphoma) (1,2). Airway involvement and ILD are the most frequent respiratory manifestations (Table 1). Lung involvement tends to be more frequent and severe in secondary than in primary SjS (193,194), with many of the lung abnormalities in secondary SjS ascribable to the associated CTD. 

Figure 6 Follicular bronchiolitis observed as an associated lesion in a patient with primary Sjogren s syndrome and a pattern of nonspecific interstitial pneumonia. The lumen is narrowed by an extensive peribronchiolar lymphocytic infiltrate. HES lOOx.

Other forms of airways disorders have also been described. Follicular bronchiolitis is a form of airways inflammation in which airways are obstructed by external compression of the bronchioles, rather than by direct luminal occlusion. A lymphocytic and plasma cell infiltrate surround the airway with germinal centers present within lymphoid follicles. Follicular bronchiohtis also has been described in Sjogren s syndrome, immunodeficiency syndromes, hypersensitivity-type reactions, and some chronic infections (14,15). 

Several risk factors for the development of OB/BOS have been identified, that can be subdivided into immunological and nonimmunological risk factors. Late or recurrent/refractory acute rejection and lymphocytic bronchitis/bronchiolitis were the most convincing (16), which together with repeated Ai acute rejection, noncompliance, human leucocyte antigen (HLA) mismatches at the A locus and total HLA mismatches, constitute the immunological risk factors (17). 

Yousem SA. Lymphocytic bronchitis/bronchiolitis in lung allograft recipients. Am J Surg Pathol 1993 17 491-496. 

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