Josune Guzman

Quantitative Analysis of Mycobacterial and Propionibacterial DNA in Lymph Nodes of Japanese and European Patients with Sarcoidosis

ABSTRACT The cause(s) of sarcoidosis is unknown. Mycobacterium spp. are suspected in Europe and Propionibacterium spp. are suspected in Japan. The present international collaboration evaluated the possible etiological links between sarcoidosis and the suspected bacterial species. Formalin-fixed and paraffin-embedded sections of biopsy samples of lymph nodes, one from each of 108 patients with sarcoidosis and 65 patients with tuberculosis, together with 86 control samples, were collected from two institutes in Japan and three institutes in Italy, Germany, and England. Genomes of Propionibacterium acnes, Propionibacterium granulosum, Mycobacterium tuberculosis, Mycobacterium avium subsp. paratuberculosis, and Escherichia coli (as the control) were counted by quantitative real-time PCR. Either P. acnes or P. granulosum was found in all but two of the sarcoid samples. M. avium subsp. paratuberculosis was found in no sarcoid sample. M. tuberculosis was found in 0 to 9% of the sarcoid samples but in 65 to 100% of the tuberculosis samples. In sarcoid lymph nodes, the total numbers of genomes of P. acnes or P. granulosum were far more than those of M. tuberculosis. P. acnes or P. granulosum was found in 0 to 60% of the tuberculosis and control samples, but the total numbers of genomes of P. acnes or P. granulosum in such samples were less than those in sarcoid samples. Propionibacterium spp. are more likely than Mycobacteria spp. to be involved in the etiology of sarcoidosis, not only in Japanese but also in European patients with sarcoidosis.

Significance of Bronchoalveolar Lavage for the Diagnosis of Idiopathic Pulmonary Fibrosis

RATIONALE According to the 2002 ATS/ERS Consensus Classification, a confident diagnosis of idiopathic pulmonary fibrosis (IPF) without surgical lung biopsy is made with consistent clinical/physiological findings and the typical features on high-resolution computed tomography (HRCT). Bronchoalveolar lavage (BAL) and/or transbronchial biopsy, one of four major criteria in the 2000 ATS/ERS IPF Statement, was no more essential in the diagnostic algorithm of 2002 ATS/ERS Consensus Classification. OBJECTIVES To evaluate the additional utility of BAL for the diagnosis of IPF. METHODS A total of 101 patients with suspected IPF on HRCT were studied. Twenty-seven patients were excluded because of lack of functional impairment (n = 20), an underlying condition causing fibrosis (n = 5), or a clinical history inconsistent with IPF (n = 2). The remaining 74 patients met all the criteria recommended in the 2002 ATS/ERS Consensus Classification for making a diagnosis in the absence of surgical biopsy. The final diagnosis was made with further examinations, including pathological analysis, in patients who showed inconsistent findings for IPF on BAL. MEASUREMENTS AND MAIN RESULTS A cut-off level of 30% for lymphocytes in BAL demonstrated a favorable discriminative power for the diagnosis of IPF. Six of the 74 patients (8%) showed a lymphocytosis of 30% or greater in BAL. Their final diagnoses were idiopathic nonspecific interstitial pneumonia (n = 3) and extrinsic allergic alveolitis (n = 3). The change in perception of the diagnosis was validated by a surgical biopsy in two cases and by subsequent outcome in four cases. CONCLUSIONS BAL lymphocytosis changed the diagnostic perception in six of 74 patients who would have been misdiagnosed as having IPF without BAL.

Bronchoalveolar lavage in interstitial lung disease.

Bronchoalveolar lavage (BAL) has become a standard diagnostic procedure for the majority of patients with interstitial disease. The technique is safe, minimally invasive, and reveals specific information in some disorders such as pulmonary alveolar proteinosis, Langerhans cell histiocytosis, alveolar hemorrhage, malignant infiltrates, or dust exposure. Here BAL can often replace lung biopsy. The results of BAL cell differentials with a lymphocytic, a neutrophilic, an eosinophilic, or a mixed cellular pattern can be used as an adjunct to diagnosis. If a BAL finding is compatible with the suspected diagnosis in the context of an appropriate disease history and clinical and radiologic findings, this can then be sufficient for disease confirmation. Recent research focused on the pathogenesis of various types of interstitial lung disorders. In this regard, BAL findings contributed to the characterization of idiopathic pulmonary fibrosis (IPF) as a condition with a predominant T-helper-2 (Th2) cytokine profile, whereas BAL findings in sarcoidosis and hypersensitivity pneumonitis are characterized by a Th1-dominant profile. The clinical value of BAL to assess the activity of disease processes and to provide prognostic information is still under debate. The routine performance of serial BAL is not recommended at present.

Localization of Propionibacterium acnes in granulomas supports a possible etiologic link between sarcoidosis and the bacterium

Sarcoidosis likely results from the exposure of a genetically susceptible subject to an environmental agent, possibly an infectious one. Mycobacterial and propionibacterial organisms are the most commonly implicated potential etiologic agents. Propionibacterium acnes is the only microorganism, however, found in sarcoid lesions by bacterial culture. To evaluate the pathogenic role of this indigenous bacterium, we screened for the bacterium in sarcoid and non-sarcoid tissues using immunohistochemical methods with novel P. acnes-specific monoclonal antibodies that react with cell-membrane-bound lipoteichoic acid (PAB antibody) and ribosome-bound trigger-factor protein (TIG antibody). We examined formalin-fixed and paraffin-embedded samples of lungs and lymph nodes from 196 patients with sarcoidosis, and corresponding control samples from 275 patients with non-sarcoidosis diseases. The samples were mostly from Japanese patients, with 64 lymph node samples from German patients. Immunohistochemistry with PAB antibody revealed small round bodies within sarcoid granulomas in 20/27 (74%) video-assisted thoracic surgery lung samples, 24/50 (48%) transbronchial lung biopsy samples, 71/81 (88%) Japanese lymph node samples, and 34/38 (89%) German lymph node samples. PAB antibody did not react with non-sarcoid granulomas in any of the 45 tuberculosis samples or the 34 samples with sarcoid reaction. In nongranulomatous areas, small round bodies detected by PAB antibody were found in alveolar macrophages of lungs and paracortical macrophages of lymph nodes from many sarcoid and some non-sarcoid patients. Large-spheroidal acid-fast bodies, Hamazaki–Wesenberg bodies, which were found in 50% of sarcoid and 15% of non-sarcoid lymph node samples, reacted with both PAB and TIG antibodies. Electron microscopy revealed that these Hamazaki–Wesenberg bodies had a single bacterial structure and lacked a cell wall with occasional protrusions from the body. The high frequency and specificity of P. acnes, detected by PAB antibody within sarcoid granulomas, indicates that this indigenous bacterium might be the cause of granuloma formation in many sarcoid patients.

Bronchoalveolar lavage in drug-induced lung disease.

Given the varying histologic reactions and differ-ent mechanisms of action, it is not surprising that no uniform constellation of BAL changes is seen in drug-induced lung disease. BAL findings are not specific for any drug-induced lung disease and the definitive diagnosis cannot rely solely on the BAL findings. BAL findings can, however, contribute to the expected clinicopathologic pattern of a given drug-induced lung disease. BAL also is helpful in the differential diagnosis, primarily in the exclusion of an infective cause and of involvement of the lungs by the underlying disease (eg, metastatic cancer or malignant lymphoma).

Chronic Hypersensitivity Pneumonitis

Hypersensitivity pneumonitis (HP) is a complex syndrome caused by the inhalation of environmental antigens. Chronic HP may mimic other fibrotic lung diseases, such as idiopathic pulmonary fibrosis. Recognition of the antigen is important for diagnosis; avoidance of further exposure is critical for treatment. Fibrosis on biopsy or high-resolution computed tomography is a predictor of increased mortality. Additional research is needed to understand why the disease develops only in a minority of exposed individuals and why cases of chronic HP may progress without further antigen exposure.

Diagnosis of sarcoidosis.

Purpose of review To describe the recent advances in the diagnostic procedures for sarcoidosis and explore future directions. Recent findings Novel imaging techniques have been explored in sarcoidosis, such as positron emission tomography using L-[3-18F]-α-methyltyrosine, which is more specific for malignancy than 18F-fluorodeoxyglucose positron emission tomography. The combined modality of L-[3-18F]-α-methyltyrosine–positron emission tomography with fluorodeoxyglucose–positron emission tomography could successfully discriminate sarcoidosis from malignancy. The finding of delayed enhancement in cardiac magnetic resonance imaging could identify cardiac involvement of sarcoidosis with higher sensitivity than echocardiography, thallium scintigraphy, and gallium scintigraphy. Endobronchial ultrasonograpy-guided transbronchial needle aspiration is a safe and useful tool for diagnosing sarcoidosis with a diagnostic accuracy, sensitivity and specificity of 85–93, 78–89, and 92–96%, respectively. Developments in genetics have demonstrated that 99% of the human leukocyte antigen DRB1*0301/DQB1*0201-positive patients with Löfgrens syndrome show a spontaneous remission, in contrast to only 55% of the human leukocyte antigen DRB1*0301/DQB1*0201-negative patients. These alleles could be novel promising factors for discriminating a prognosis in Löfgrens syndrome. Summary Recent development including novel imaging techniques, novel biopsy procedures, and genetic analyses could be of value for the diagnosis of sarcoidosis.

Thalidomide reduces IL-18, IL-8 and TNF-α release from alveolar macrophages in interstitial lung disease

Thalidomide exhibits diverse actions of anti-inflammation, immunomodulation and anti-angiogenesis. The efficacy of thalidomide treatment in sarcoidosis with lupus pernio is thought to be due to inhibition of tumour necrosis factor (TNF)-α. The mechanisms that underlie the properties of thalidomide are still unclear in interstitial lung disease. The current authors investigated the potential inhibitory effects of thalidomide at concentrations of 0.1, 0.01 and 0.001 mM on the production of transforming growth factor-β, TNF-α, interleukin (IL)-1β, IL-6, IL-8, IL-10, IL-12p70, IL-12p40 and IL-18 by alveolar macrophages from bronchoalveolar lavage in patients with sarcoidosis (n = 8), hypersensitivity pneumonitis (HP; n = 8) and idiopathic pulmonary fibrosis (IPF; n = 12). In sarcoidosis and HP patients, thalidomide induced a dose-dependent, partial suppression of lipopolysacchride (LPS)-stimulated TNF-α, IL-12p40 and IL-18 release. At the highest thalidomide concentration (0.1 mM), LPS-stimulated IL-8 production was also suppressed. In IPF patients, although spontaneous production of TNF-α, IL-12p40, IL-18 and IL-8 was lower than in sarcoidosis and HP patients, with LPS stimulation the cytokines were significantly elevated and also partially inhibited by thalidomide. In conclusion, thalidomide has the potential to improve the therapeutic regimens for sarcoidosis, hypersensitivity pneumonitis and idiopathic pulmonary fibrosis by reducing tumour necrosis factor-α, interleukin-12p40, interleukin-18 and interleukin-8 production.

Pulmonary alveolar proteinosis: new insights from a single-center cohort of 70 patients.

BACKGROUND Pulmonary alveolar proteinosis (PAP) is a rare syndrome characterized by the intra-alveolar accumulation of surfactant lipids and proteins. The aim of the study is to describe the epidemiologic, clinical, physiologic, and laboratory features of PAP in a large single-center cohort of patients with PAP. STUDY POPULATION Over 30 years, 70 patients with PAP were managed at our institution, 64 with primary and 6 with secondary PAP. RESULTS The mean age at diagnosis was 43 years with a male to female ratio of 1.3. BAL was the most commonly applied diagnostic method, performed in 83% of cases. A history of smoking was seen in 79%, and of dust exposure in 54%, most commonly to aluminum, silica and sawdust. GM-CSF autoantibody correlated with clinical outcome and KL-6 with diffusing capacity. The number of whole lung lavages (WLL) necessary to reach remission was higher in current smokers. CONCLUSIONS This study shows that the use of BAL for the diagnosis of PAP can reduce the need of histological confirmation. A history of dust or fume inhalation is strongly associated with PAP, also with the autoimmune form. Smoking seems to influence the response to treatment, increasing the number of WLL necessary to reach remission.

Diagnostic Modalities in Sarcoidosis: BAL, EBUS, and PET

Advances have been made in minimally invasive diagnostic procedures in sarcoidosis, including bronchoalveolar lavage (BAL), endobronchial ultrasonography-guided transbronchial needle aspiration (EBUS-TBNA), and positron emission tomography (PET). Several independent groups found almost identical predictive values of the CD4:CD8 ratio in BAL for the diagnosis of sarcoidosis. A CD4:CD8 ratio greater than 3.5 shows a high specificity of 93 to 96% for sarcoidosis, but the sensitivity is low (53 to 59%). EBUS-TBNA is a safe and useful tool for diagnosing sarcoidosis stage I and II with a sensitivity of 83 to 93% and a specificity of 100%. Novel imaging techniques have been explored, such as PET using L-[3- (18)F] fluoro-alpha-methyltyrosine ( (18)F-F MT), which is more specific for malignancy than (18)F-fluorodeoxyglucose ( (18)F-FDG)-PET. The combined modality of FMT-PET with FDG-PET could successfully discriminate sarcoidosis from malignancy. These recent developments including novel biopsy procedures and novel imaging techniques could be of value to diagnosing sarcoidosis.