Increased serum level of vascular endothelial growth factor in Mycobacterium avium complex infection

Comparing the Differential Diagnostic Values of 18F-Alfatide II PET/CT between Tuberculosis and Lung Cancer Patients

Purpose

To compare the differential diagnostic values of ¹⁸F-Alfatide II PET/CT between tuberculosis and lung cancer patients and in patients with sarcoidosis and common inflammation.

Methods

Nine inflammation patients (4 tuberculosis, 3 sarcoidosis, and 2 common inflammation) and 11 lung cancer patients were included in this study. All patients underwent ¹⁸F-FDG and ¹⁸F-Alfatide II PET/CT within 2 weeks, followed by biopsy and surgery. The maximized standard uptake value (SUVmax) and the mean standard uptake value (SUVmean) were evaluated.

Results

The active tuberculosis lesions showed a high accumulation of ¹⁸F-FDG, but varying degrees of accumulation of ¹⁸F-Alfatide II, including negative results. The SUVmax of ¹⁸F-Alfatide II in malignant lesions was significantly higher than that in tuberculosis (4.08 ± 1.51 versus 2.63 ± 1.34, P = 0.0078). Three patients with sarcoidosis showed negative results in ¹⁸F-Alfatide II PET/CT.

Conclusions

The expression of α_Vβ₃ is much lower in tuberculosis as compared to that in lung cancer, and accumulation of ¹⁸F-Alfatide II varied even in lesions of the same patient. The negative results of sarcoidosis patients led to the speculation that α_Vβ₃ was not expressed in those lesions.

The trend and the disease prediction of vascular endothelial growth factor and placenta growth factor in nontuberculous mycobacterial lung disease

Nontuberculous mycobacteria (NTM)-lung disease (LD) is an increasing health problem worldwide. The diagnosis of this disease remains difficult, however the application of placenta growth factor (PlGF) and vascular endothelial growth factor (VEGF) has not yet been studied. We screened patients with Mycobacterium avium complex or M. abscessus isolated from sputum, and enrolled 32 patients with NTM-LD and 93 with NTM pulmonary colonization. The NTM-LD group had a lower body mass index, higher proportion of bronchiectasis, more respiratory symptoms and pulmonary lesions, and higher titers of sputum acid-fast stain than the NTM pulmonary colonization group. The plasma level of PlGF was lower in the NTM-LD group than in the NTM colonization group, whereas the level of VEGF was higher in the NTM-LD group. In multivariable logistic regression analysis excluding NTM cultures, the predictive model for NTM-LD included sputum AFS titer, a nodular-bronchiectasis radiographic pattern, plasma VEGF/PlGF ratio, and chest radiographic score (VEGF/P1GF ratio became not significant as a factor in multivariable generalized linear model). The four-factor predictive index had good positive likelihood ratio and negative likelihood ratio for predicting NTM-LD in the patients with NTM in their sputum.

Depletion of Alveolar Macrophages Does Not Prevent Hantavirus Disease Pathogenesis in Golden Syrian Hamsters

Andes virus (ANDV) is associated with a lethal vascular leak syndrome in humans termed hantavirus pulmonary syndrome (HPS). The mechanism for the massive vascular leakage associated with HPS is poorly understood; however, dysregulation of components of the immune response is often suggested as a possible cause. Alveolar macrophages are found in the alveoli of the lung and represent the first line of defense to many airborne pathogens. To determine whether alveolar macrophages play a role in HPS pathogenesis, alveolar macrophages were depleted in an adult rodent model of HPS that closely resembles human HPS. Syrian hamsters were treated, intratracheally, with clodronate-encapsulated liposomes or control liposomes and were then challenged with ANDV. Treatment with clodronate-encapsulated liposomes resulted in significant reduction in alveolar macrophages, but depletion did not prevent pathogenesis or prolong disease. Depletion also did not significantly reduce the amount of virus in the lung of ANDV-infected hamsters but altered neutrophil recruitment, MIP-1α and MIP-2 chemokine expression, and vascular endothelial growth factor (VEGF) levels in hamster bronchoalveolar lavage (BAL) fluid early after intranasal challenge. These data demonstrate that alveolar macrophages may play a limited protective role early after exposure to aerosolized ANDV but do not directly contribute to hantavirus disease pathogenesis in the hamster model of HPS.

IMPORTANCE

Hantaviruses continue to cause disease worldwide for which there are no FDA-licensed vaccines, effective postexposure prophylactics, or therapeutics. Much of this can be attributed to a poor understanding of the mechanism of hantavirus disease pathogenesis. Hantavirus disease has long been considered an immune-mediated disease; however, by directly manipulating the Syrian hamster model, we continue to eliminate individual immune cell types. As the most numerous immune cells present in the respiratory tract, alveolar macrophages are poised to defend against hantavirus infection, but those antiviral responses may also contribute to hantavirus disease. Here, we demonstrate that, like in our prior T and B cell studies, alveolar macrophages neither prevent hantavirus infection nor cause hantavirus disease. While these studies reflect pathogenesis in the hamster model, they should help us rule out specific cell types and prompt us to consider other potential mechanisms of disease in an effort to improve the outcome of human HPS.

Association of serum adiponectin level with albuminuria in chronic kidney disease patients

BACKGROUND

Adiponectin, a peptide hormone secreted from adipocytes, exerts anti-diabetic, anti-atherogenic, and anti-inflammatory properties. We aimed to determine the relationship between serum adiponectin levels and albuminuria, and evaluate determinant factors for serum adiponectin in patients with chronic kidney disease (CKD).

METHODS

In total, 1442 CKD patients were included and divided into three groups according to their albumin-to-creatinine ratios: patients with normoalbuminuria (N = 228), microalbuminuria (N = 444), and macroalbuminuria (N = 761). Serum adiponectin was specifically assayed with a commercially available enzyme-linked immunosorbent assay kit.

RESULTS

Serum adiponectin was significantly higher in patients with macroalbuminuria than in those without macroalbuminuria (9.7 ± 6.0, 12.4 ± 9.0, and 14.9 ± 11.0 μg/mL in patients with normoalbuminuria, microalbuminuria, and macroalbuminuria, respectively). Univariate linear regression analysis showed that the serum adiponectin concentrations were correlated with age, the albumin-to-creatinine ratio, total cholesterol, low-density lipoprotein cholesterol, and high-density lipoprotein cholesterol, whereas they were negatively correlated with body mass index, the estimated glomerular filtration rate, and serum albumin and triglyceride levels. The stepwise regression multiple analysis showed that sex; the estimated glomerular filtration rate; body mass index; total cholesterol, high-density lipoprotein cholesterol, and triglyceride levels; and logarithm of the albumin-to-creatinine ratio were independently associated with the logarithm of serum adiponectin levels (r = 0.55, p < 0.001).

CONCLUSION

Serum adiponectin concentrations are higher in patients with increasing albuminuria, and these levels are associated with renal insufficiency and lipid profiles.

Angiogenic activity of sera from pulmonary tuberculosis patients in relation to IL-12p40 and TNFα serum levels

The role of angiogenesis in the pathogenesis of tuberculosis (TB) is not clear. The aim of this study was to examine the effect of sera from TB patients on angiogenesis induced by different subsets of normal human mononuclear cells (MNC) in relation to IL-12p40 and TNFα serum levels. Serum samples from 36 pulmonary TB patients and from 22 healthy volunteers were evaluated. To assess angiogenic reaction the leukocytes-induced angiogenesis test according to Sidky and Auerbach was performed. IL-12p40 and TNFα serum levels were evaluated by ELISA. Sera from TB patients significantly stimulated angiogenic activity of MNC compared to sera from healthy donors and PBS (p < 0.001). The number of microvessels formed after injection of lymphocytes preincubated with sera from TB patients was significantly lower compared to the number of microvessels created after injection of MNC preincubated with the same sera (p < 0.016). However, the number of microvessels created after the injection of lymphocytes preincubated with sera from healthy donors or with PBS alone was significantly higher (p < 0.017). The mean levels of IL-12p40 and TNFα were significantly elevated in sera from TB patients compared to healthy donors. We observed a correlation between angiogenic activity of sera from TB patients and IL-12p40 and TNFα serum levels (p < 0.01). Sera from TB patients constitute a source of mediators that participate in angiogenesis and prime monocytes for production of proangiogenic factors. The main proangiogenic effect of TB patients’ sera is mediated by macrophages/monocytes. TNFα and IL-12p40 may indirectly stimulate angiogenesis in TB.

Nontuberculous mycobacterial pulmonary disease

PURPOSE OF REVIEW

Pulmonary disease caused by nontuberculous mycobacteria is occurring with greater frequency, and previously unrecognized manifestations of nontuberculous mycobacteria are being identified. Paralleling this increase, improvements in laboratory techniques now allow for more precise identification of nontuberculous mycobacteria and recognition of new species. Consequently, clinicians are more often confronted with diagnostic and therapeutic challenges relevant to the care of patients with nontuberculous mycobacterial lung disease.

RECENT FINDINGS

In response to this burgeoning clinical need, the American Thoracic Society and Infectious Disease Society of America jointly published an updated consensus statement on nontuberculous mycobacterial pulmonary disease in 2007. This document, in conjunction with original investigations in the field, has advanced our understanding of the pathogenesis of nontuberculous mycobacterial lung disease, its clinical manifestations, and the efficacy of medical and surgical therapy.

SUMMARY

The present article will review our current understanding of nontuberculous mycobacterial pulmonary disease with particular emphasis on pathogenesis, diagnosis, and therapeutic decision making. Areas of clinical controversy in which current data are inadequate to guide our decision making will be highlighted.

Respirology year-in-review 2006: Basic science

The year 2006 was a good year for basic science publications in Respirology with a lot of the studies being relevant to clinical practice. In this respect many of the publications focused on biomarkers of disease and so much so that these have been discussed at the end of this review. The majority of manuscripts are related to airway diseases, respiratory infections, interstitial lung diseases and lung cancers, and are discussed under these headings.