A case of diffuse panbronchiolitis (DPB) in a patient positive for HTLV-1

Human T-cell leukaemia virus type 1 associated pulmonary disease: clinical and pathological features of an under-recognised complication of HTLV-1 infection

The lung is one of several organs that can be affected by HTLV-1 mediated inflammation. Pulmonary inflammation associated with HTLV-1 infection involves the interstitium, airways and alveoli, resulting in several clinical entities including interstitial pneumonias, bronchiolitis and alveolitis, depending on which structures are most affected. Augmentation of the inflammatory effects of HTLV-1 infected lymphocytes by recruitment of other inflammatory cells in a positive feedback loop is likely to underlie the pathogenesis of HTLV-1 associated pulmonary disease, as has been proposed for HTLV-1 associated myelopathy. In contrast to the conclusions of early case series, HTLV-1 associated pulmonary disease can be associated with significant parenchymal damage, which may progress to bronchiectasis where this involves the airways. Based on our current understanding of HTLV-1 associated pulmonary disease, diagnostic criteria are proposed.

A case of diffuse panbronchiolitis complicated by peripheral T cell lymphoma not otherwise specified

We report a case of diffuse panbronchiolitis (DPB) complicated by peripheral T cell lymphoma not otherwise specified. A 40-year-old Chinese man presented with intermittent fever, cough and significant white sputum production for more than 9 years, in addition to dyspnea and chest congestion that worsened after exercise. A chest CT scan indicated diffuse centrilobular fine nodular opacities with a 'tree-in-bud' appearance in both lungs. An open-lung biopsy was performed, and DPB was diagnosed by histopathological analysis. Three months later, the patient's pulmonary symptoms worsened. A chest CT of both lungs revealed multiple patchy opacities as well as enlargement of the hilar, mediastinal and multiple superficial lymph nodes. A whole-body bone scan revealed multiple osteolytic lesions located in the thoracic, lumbar and sacral spine. A biopsy of the right supraclavicular lymph node was performed, and peripheral T cell lymphoma not otherwise specified was diagnosed histopathologically. Cases of DPB complicated by non-Hodgkin's lymphoma are a rare occurrence. To our knowledge, there is only one earlier report of such a case in the literature (in Japanese). However, the prevalence of DPB complicated by T cell tumors is relatively high, indicating a possible association in pathogenesis of T cell disorders and DPB.

Pathology of small airways disease

CONTEXT

The term small airways disease encompasses a generally poorly understood group of lung diseases that may arise primarily within the small airways or secondarily from diseases primarily affecting the bronchi or lung parenchyma. Their histology may be confusing; however, because treatments and prognoses vary, correct pathologic diagnosis is important.

OBJECTIVE

To present a nonexhaustive review of the pathology of primary and secondary small airways diseases, including small airways disease related to tobacco; to various other exposures, including mineral dusts; to diseases involving other areas of the lung with secondary bronchiolar involvement; and to recently described bronchiolitic disorders.

DATA SOURCES

Current literature is reviewed.

CONCLUSIONS

Small airways diseases include a wide variety of diseases of which the pathologist must consider. Uncommon conditions such as diffuse idiopathic neuroendocrine cell hyperplasia and diffuse panbronchiolitis may show relatively specific diagnostic features histologically; however, most small airways diseases exhibit nonspecific histologic features. Conditions not considered primary pulmonary diseases, such as collagen vascular diseases, bone marrow transplantation, and inflammatory bowel disease, must also be considered in patients with small airways changes histologically. Clinical and radiologic correlation is important for obtaining the best possible diagnosis.