Stimulated expression of ELR+ chemokines, VEGFA and TNF-AIP3 promote mycobacterial dissemination in extrapulmonary tuberculosis patients and Cavia porcellus model of tuberculosis

Pathogenic mycobacteria induce and accelerate blood vessel formation driven by extensive inflammation during granuloma formation, which is a central feature of mycobacterial pathogenesis. Tumor necrosis factor-alpha (TNF-α) enhances the expression of vascular endothelial growth factor (VEGF) and glutamic acid-leucine-arginine (ELR+) chemokines, which are potent inducers of vascularization. Most of the reported research work contends that VEGF growth factor induces neovascularization in human tuberculosis (TB) patients, but the evidence is inconclusive. Considerable ambiguity exists concerning the factors responsible for miliary tuberculosis. To identify such factors, we proposed an alternative explanation that could be found in miliary tuberculosis (MTB) cases. We performed a comparative analysis of angiogenic factors TNF-α, VEGF, and angiogenic ELR+ CXC and CC chemokine ligands in extrapulmonary tuberculosis (EPTB) and pulmonary tuberculosis (PTB) patients. To observe the relationship of these factors with the severity of bacterial burden, guinea pigs were infected with Mycobacterium tuberculosis (M.tb) and levels of the angiogenic factors were examined at different time intervals. Expression of these factors also exhibited a significant positive correlation with bacterial burden in other organs like the spleen, liver, and lymph nodes. We demonstrated statistical data on bacterial burden at different time points following the dissemination of infection in guinea pigs. In this study, we observed that there was a stimulated increase in the expression of ELR+ chemokines and VEGF in EPTB patients as compared to PTB patients. Following increased dissemination, the host immune response clears bacteria from the lungs during disease progression in guinea pigs.

A complete categorization of multiscale models of infectious disease systems

Modelling of infectious disease systems has entered a new era in which disease modellers are increasingly turning to multiscale modelling to extend traditional modelling frameworks into new application areas and to achieve higher levels of detail and accuracy in characterizing infectious disease systems. In this paper we present a categorization framework for categorizing multiscale models of infectious disease systems. The categorization framework consists of five integration frameworks and five criteria. We use the categorization framework to give a complete categorization of host-level immuno-epidemiological models (HL-IEMs). This categorization framework is also shown to be applicable in categorizing other types of multiscale models of infectious diseases beyond HL-IEMs through modifying the initial categorization framework presented in this study. Categorization of multiscale models of infectious disease systems in this way is useful in bringing some order to the discussion on the structure of these multiscale models.

Paracoccidioidomycosis with sarcoid-like lesions:a diagnostic challenge

Clinical presentation of paracoccidioidomycosis (PCM) can be diverse. Morphology and quantity of skin lesions depends on interactions between host immunity and fungus virulence. Diagnosis can be a challenge considering that this fungus has low virulence and some individuals have immunity to microorganism, which results in well-marked granulomas without visible microorganisms. We report herein a clinical presentation of sarcoid-like PCM, initially diagnosed as tuberculoid leprosy. This rare type of PCM is often mistaken for other types of chronic granulomatous diseases. Diagnosis was confirmed after 4 years when a special stain analysis helped in the identification of the specific etiologic agent.

Mediastinal Granulomatous Inflammation and Overall Survival in Patients with a History of Malignancy

RATIONALE

Investigators have postulated that mediastinal granulomatous inflammation is associated with prolonged overall survival in patients with cancer.

OBJECTIVES

We sought to determine whether mediastinal granulomatous inflammation affects overall survival in patients with a history of treated cancer.

METHODS

Patients with a history of treated cancer who underwent endobronchial ultrasound-transbronchial needle aspiration (EBUS-TBNA) for evaluation of mediastinal or hilar lymphadenopathy were grouped based on whether they had mediastinal granulomatous inflammation or benign mediastinal lymphadenopathy without granulomas. Overall survival from the date of EBUS-TBNA to cancer-related death or to last follow-up in patient groups was compared.

MEASUREMENTS AND MAIN RESULTS

We reviewed the records of 106 patients (44 with mediastinal granulomatous inflammation and 62 with benign mediastinal lymphadenopathy). The 3-year survival rate was 90% overall and 93 and 88% in patients with mediastinal granulomatous inflammation and benign mediastinal lymphadenopathy, respectively (P=0.40). After multivariate adjustment, whether patients had mediastinal granulomatous inflammation or benign mediastinal lymphadenopathy did not significantly affect the risk of cancer death (mediastinal granulomatous inflammation to benign mediastinal lymphadenopathy hazard ratio, 1.27; P=0.76).

CONCLUSIONS

These results suggest that patients who develop mediastinal granulomatous inflammation after cancer treatment do not have an increased overall survival when compared with patients who develop benign mediastinal lymphadenopathy. EBUS-TBNA is warranted for patients with treated cancer who develop mediastinal and/or hilar lymphadenopathy to avoid erroneous upstaging or misdiagnosis of cancer recurrence that would lead to suboptimal management.