Equivalent SARS-CoV-2 viral loads by PCR between nasopharyngeal swab and saliva in symptomatic patients

Emerging evidences have shown the utility of saliva for the detection of SARS-CoV-2 by PCR as alternative to nasopharyngeal swab (NPS). However, conflicting results have been reported regarding viral loads between NPS and saliva. We conducted a study to compare the viral loads between NPS and saliva in 42 COVID-19 patients. Viral loads were estimated by the cycle threshold (Ct) values. SARS-CoV-2 was detected in 34 (81%) using NPS with median Ct value of 27.4, and 38 (90%) using saliva with median Ct value of 28.9 (P = 0.79). Kendall's W was 0.82, showing a high degree of agreement, indicating equivalent viral loads in NPS and saliva. After symptom onset, the Ct values of both NPS and saliva continued to increase over time, with no substantial difference. Self-collected saliva has a detection sensitivity comparable to that of NPS and is a useful diagnostic tool with mitigating uncomfortable process and the risk of aerosol transmission to healthcare workers.

Unique Mortality Profile in Japanese Patients with COPD: An Analysis from the Hokkaido COPD Cohort Study

Purpose

Causes of death may be unique and different in Japanese patients with COPD because they are generally older, thinner, experience fewer exacerbations, and live longer than those in other countries. We investigated the detailed mortality profile in the Hokkaido COPD cohort study, which completed a 10-year follow-up with a very low dropout rate.

Patients and Methods

We prospectively examined the 10-year natural history in 279 Japanese patients with COPD (GOLD 1, 26%; GOLD 2, 45%; GOLD 3, 24%; and GOLD 4, 5%). The majority of patients were male, and the average age at baseline was 69 years old. About 95% of all patients had accurate mortality data. The risk factors for mortality were also analyzed.

Results

During the 10 years, 112 patients (40%) died. Their median survival time was 6.1 years (interquartile range: 4.7–7.9 years), and age at death was 79 ± 6 years old (mean ± SD). Respiratory diseases, including pneumonia, were the leading causes of death in 45 (40%), followed by lung cancer in 24 (21%), other cancers in 18 (16%), and cardiovascular diseases in 12 (11%). In particular, lung cancer-related death was equally distributed across all COPD stages, with a higher proportion of lung cancer in the relatively younger generation (<64 years old). Older age at baseline, lower BMI, and severer emphysema were significant risk factors for all-cause mortality.

Conclusion

The unique mortality profile observed in this study should be considered when designing strategies for the management of patients with COPD in any geographic region.

[Pyothorax-associated lymphoma with the expression of Epstein-Barr virus latent genes]

An 84-year-old man, who had received artificial pneumothorax for pulmonary tuberculosis 67 years previously, complained of severe chest pain. Chest CT revealed chronic pyothorax with multiple heterogeneously enhanced cavity lesions in the wall of the right intrathoracic space. ¹⁸FDG-PET revealed that the lesions showed an abnormal uptake. CT-guided biopsy was performed and he was diagnosed with pyothorax-associated lymphoma (PAL); the histological diagnosis was diffuse large B cell lymphoma (DLBCL). Furthermore, immunohistochemical staining revealed that the tumor cells were positive for EBNA-2 and LMP-1, suggesting that the latent gene products of Epstein-Barr virus were associated with the development of PAL. The patient was treated with chemotherapy, including rituximab; however, the treatment was discontinued due to the development of severe delirium after chemotherapy. We should keep in mind that elderly patients with a long history of chronic pyothorax are at risk of developing malignant lymphoma. We report the present case with a brief review of the literature.

Role of secretory leukocyte protease inhibitor in the development of subclinical emphysema

Secretory leukocyte protease inhibitor (SLPI) is a potent inhibitor of human leukocyte elastase. In some chronic airway diseases, the level of SLPI is decreased in sputum, leading to the continuation of neutrophil inflammation. In this study, the role of SLPI in subclinical pulmonary emphysema was examined. Sequential bronchoalveolar lavage was performed in an attempt to separately evaluate the levels of SLPI in the large airways and in the peripheral airways for two groups of smokers. One group had subclinical emphysema by computed-tomography scans and one group did not. SLPI localized in alveolar macrophages (AM) was also assessed. The level of SLPI was significantly elevated in the peripheral airways from the subjects with emphysema compared to those without emphysema (1589.2+/-353.9 versus 729.1+/-31.0 ng x mL(-1)), although it was similar in the large airways (3442.3+/-499.6 versus 2535.7+/-578.8 ng x mL(-1)). There was a trend for higher amount of SLPI to be released from AM in subjects with subclinical emphysema, although this did not reach statistical significance. In conclusion, there is compensatory upregulation of secretory leukocyte protease inhibitor in peripheral airways in subclinical pulmonary emphysema, which is in sharp contrast to the decreased level of secretory leukocyte protease inhibitor reported in some chronic airway diseases.

Increased levels of interleukin-8 in BAL fluid from smokers susceptible to pulmonary emphysema

BACKGROUND

It has previously been shown that smokers with computed tomographic (CT) evidence of subclinical emphysema have signs of neutrophil activation, despite having no appreciable increase in the number of neutrophils in their bronchoalveolar lavage (BAL) fluid.

METHODS

The levels of the following chemoattractants in BAL fluid from 61 community based older volunteers classified into four groups according to current smoking status and the presence or absence of emphysema were determined: interleukin 8 (IL-8), epithelial neutrophil activating protein 78 (ENA-78) and leukotriene B(4) (LTB(4)) which are primarily chemotactic for neutrophils; monocyte chemoattractant protein 1 (MCP-1) and macrophage inflammatory protein-1alpha (MIP-1alpha) which are predominantly chemotactic for mononuclear leucocytes.

RESULTS

Of the five chemoattractants studied, only the level of IL-8 in BAL fluid clearly distinguished between subjects with and without emphysema among current smokers (median values 34.7 and 12.2 pg/ml, respectively, p<0.01). In addition, the levels of IL-8 and neutrophil elastase-alpha(1) protease inhibitor complex in BAL fluid were significantly correlated (r=0.65, p<0.01). There was no difference in either the release of IL-8 from cultured alveolar macrophages at 24 hours or the expression of IL-8 messenger RNA of alveolar macrophages in the two groups of current smokers with and without emphysema.

CONCLUSION

An accelerated response of IL-8 to chronic smoking is a factor that characterises those smokers who are susceptible to pulmonary emphysema, although the cellular source of IL-8 remains to be determined.

Decline in FEV(1) in community-based older volunteers with higher levels of neutrophil elastase in bronchoalveolar lavage fluid

BACKGROUND

Neutrophil elastase (NE) is thought to be one of the key proteinases in the development of chronic obstructive pulmonary disease (COPD). Previously, we have shown that the NE-alpha1-proteinase inhibitor (NE-alpha1PI) complex in bronchoalveolar lavage (BAL) fluid was markedly elevated in asymptomatic smokers who had subclinical emphysema on CT scans. We proposed that excessive NE-alpha1PI complex in BAL fluid was a factor which might differentiate smokers who were developing emphysema from others.

OBJECTIVE

In this study, we addressed the question of whether elevated levels of the NE-alpha1PI complex in BAL fluid are linked to the accelerated decline in pulmonary functions in those subjects.

METHODS

We conducted a follow-up study to analyze the decline in FEV(1) for 4.3 years on average for 26 community-based volunteers who had received pulmonary function tests, CT scans and BAL. The levels of the NE-alpha1PI complex in BAL fluid and in plasma was measured.

RESULTS

Neither pulmonary function measurements nor the presence of emphysema on CT scans could predict the decline in FEV(1). The number of inflammatory cells in BAL fluid was also not an indicator of progression. By contrast, subjects with higher levels of the NE-alpha1PI complex in BAL fluid had a significantly accelerated decline in FEV(1) compared to those with lower levels.

CONCLUSION

These data seem to support the hypothesis that NE in the lung is related to the onset and/or progression of COPD.

Gene polymorphism for microsomal epoxide hydrolase and susceptibility to emphysema in a Japanese population

Recently, it was reported that gene polymorphism for microsomal epoxide hydrolase (mEPHX), an enzyme involved in the first-pass metabolism of epoxide intermediates, was associated with susceptibility to emphysema. This association was examined in a Japanese population, performing polymerase chain reaction (PCR)-based direct sequencing and restriction fragment length polymorphism assays for variant forms of mEPHX. The subjects consisted of 79 smokers with moderate to severe emphysema diagnosed by lung computed tomography scans, 58 smokers without emphysema, with a comparable smoking history, and 114 consecutive subjects who undertook annual health checkups. The allele frequency of exon 3 Tyr113 to His113, which was reported to confer slow mEPHX activity, was substantially higher in the population control group compared with that of the Caucasian control subjects in a previous study. However, neither the genotype distribution of exon 3, nor that of exon 4 His139 to Arg139, was significantly different between the two groups of smokers. These data indicate that the gene polymorphism for mEPHX is not associated with susceptibility to emphysema in the Japanese population. The discrepancy between the two studies may be explained either by racial difference or by the selection bias of subjects in the previous study, which examined those who had only mild to moderate emphysema with lung cancer or those who were clinically diagnosed as having chronic obstructive pulmonary disease.

[A comparative study of computed tomographic techniques for the detection of emphysema in middle-aged and older patient populations]

Helical-scan computed tomography (CT) is now widely utilized as a mass screening procedure for lung cancer. By adding 3 slices of high-resolution CT (HRCT) to the standard screening procedure, we were able to compare the efficacy of helical-scan CT and HRCT in detecting pulmonary emphysema. Additionally, the prevalence of emphysema detected by HRCT was examined as a function of patient age and smoking history. The subjects (106 men and 28 women) were all community-based middle-aged and older volunteers who participated in a mass lung cancer screening program. Based on visual assessments of the CT films, emphysema was detected in 29 subjects (22%) by HRCT, but in only 4 (3%) by helical-scan CT. Although the prevalence of emphysema was higher among subjects with a higher smoking index, no correlations with age were observed. We concluded that the efficacy of helical scan CT in detecting pulmonary emphysema can be significantly improved with the inclusion of 3 slices of HRCT, and confirmed that cigarette smoking is linked to the development of pulmonary emphysema.

Neutrophil granule proteins in bronchoalveolar lavage fluid from subjects with subclinical emphysema

Evidence for the contribution of neutrophils to the pathogenesis of pulmonary emphysema is not convincing. We evaluated neutrophil involvement in subclinical pulmonary emphysema by measuring human neutrophil lipocalin (HNL) and two matrix metalloproteinases, gelatinase B (MMP-9) and neutrophil collagenase (MMP-8), in bronchoalveolar lavage fluid (BALF) from 65 community-based older volunteers. HNL is a recently isolated 24-kD protein secreted from secondary granules of activated neutrophils. Despite no appreciable increase in the number of neutrophils, the level of HNL was significantly increased in BALF from subjects with emphysema evidenced by computed tomography regardless of current smoking, as compared with smokers without emphysema. The levels of MMP-9 and MMP-8 were also significantly higher in current smokers with emphysema than in those without emphysema. The appearance of a 130-kD HNL/MMP-9 complex on gelatin zymography and HNL immunoblot indicated neutrophils to be a significant source of MMP-9 in the subjects' BALF. In a 24-h culture medium of alveolar macrophages, only a latent form of MMP-9 was detected, and there was no difference in the level of MMP-9 between the groups. These data provide further evidence for neutrophil involvement in subclinical pulmonary emphysema.

Cysteine proteinases and cystatin C in bronchoalveolar lavage fluid from subjects with subclinical emphysema

This study examined the role of cysteine proteinases and their inhibitor in the development of emphysema in comparison with neutrophil elastase (NE) complexed with alpha1-protease inhibitor (NE-alpha1-PI), which was previously demonstrated to be increased in bronchoalveolar lavage (BAL) fluid from subjects with subclinical emphysema. Eight nonsmokers and 31 current smokers with (n=17) and without (n=14) emphysema, as evidenced by lung computed tomographic scans, were studied. The concentrations of immunologically detected cathepsin L and cystatin C, but not cathepsin B, were significantly increased in BAL fluid from the smokers with emphysema compared with those without emphysema, although the activity of cathepsin L, measured using a synthetic substrate and cathepsin L, released from cultured alveolar macrophages at 24 h, did not show any significant difference between the two groups. When comparison was made only for the subjects aged <60 yrs, the difference between the two groups disappeared for cathepsin L, but remained for NE-alpha1-PI. There was no significant correlation between the level of cathepsin L and that of NE-alpha1-PI in BAL fluid from the subjects with emphysema. In conclusion, increased levels of cathepsin L and cystatin C were demonstrated in bronchoalveolar lavage fluid from subjects with subclinical emphysema. However, the roles of cathepsin L and neutrophil elastase in the development of emphysema may vary between subjects and between the young and the old.

[Neutrophil elastase and elastin-derived peptides in BAL fluid and emphysematous changes on CT scans]

We examined the relationship between neutrophil elastase, elastin-derived peptides in bronchoalveolar lavage (BAL) fluid, and the development of pulmonary emphysema. The level of neutrophil elastase was higher in asymptomatic current smokers with emphysematous changes on computed tomographic scans than in current smokers without emphysematous changes, and was found to be correlated with the level of elastin-derived peptides in BAL fluid. Subjects with high levels of neutrophil elastase in BAL fluid had faster annual declines in FEV1. We conclude that the level of neutrophil elastase in BAL fluid can be used to differentiate asymptomatic cigarette smokers who are at risk for pulmonary emphysema from those who are not.

Elastin-derived peptides and neutrophil elastase in bronchoalveolar lavage fluid

To evaluate effects of current smoking on the breakdown of lung elastin, we measured levels of elastin-derived peptides (EDP) in unconcentrated bronchoalveolar lavage (BAL) fluid from 42 community-based older asymptomatic volunteers (60 +/- 11 yr [mean +/- SD]) and examined the relationships of the concentrations of EDP with immunologically detected neutrophil elastase (NE) bound with alpha(1)-proteinase inhibitor and with esterolytic activity against the NE-sensitive synthetic substrate, methoxysuccinyl-alanyl-alanyl-prolyl-valyl paranitroanilide (MEOSAAPVNA). The measurement of EDP levels was carried out by an indirect, competitive ELISA, using a sheep IgG fraction generated against insoluble human lung elastin as a primary antibody. EDP concentrations were significantly elevated in current smokers (n = 24) compared with age-matched noncurrent smokers (n = 18) (29.9 +/- 3.5 [mean +/- SE] versus 17.0 +/- 1.8 ng/mg BAL fluid albumin, p < 0.01). We found weak but significant correlations of EDP levels with NE-alpha(1)-proteinase inhibitor complex (r = 0.38, p < 0.05) and with the esterolytic activity against the NE-sensitive synthetic substrate in BAL fluid (r = 0.65, p < 0.001). In addition, EDP levels in BAL fluid had a significant positive relationship with plasma cotinine concentrations (r = 0.53, p < 0.001), though not with pack-years of smoking (r = 0.1, NS). These data provide further evidence that the concentrations of EDP increase in BAL fluid from current smokers compared with noncurrent smokers and that enhanced breakdown of the lung elastin is associated with the increased load of NE in the lung.

Lymphoproliferative disorder of granular lymphocytes (natural killer cell type) with interstitial pneumonia in a patient with familial pancytopenia

A 50-year-old woman is presented here with natural killer (NK) cell type lymphoproliferative disorder of granular lymphocytes. She was admitted to the hospital because of dyspnea on exertion. Chest X-ray revealed bilateral reticular shadows. Open lung biopsy demonstrated usual interstitial pneumonia (UIP). Her white blood cell count was 3,900/mm3, of which 55% was large granular lymphocytes (LGLs). The LGLs were CD3- CD16+CD56+, and the clonality of them was not confirmed. Despite steroid therapy, she died from exacerbation of UIP complicated with opportunistic infection. The patient, her father and son had pancytopenia. Congenital immunological abnormality might cause both large granular lymphocytosis and UIP.