Modeling Chagas Disease at Population Level to Explain Venezuela's Real Data

Objectives

In this paper we present an age-structured epidemiological model for Chagas disease. This model includes the interactions between human and vector populations that transmit Chagas disease.

Methods

The human population is divided into age groups since the proportion of infected individuals in this population changes with age as shown by real prevalence data. Moreover, the age-structured model allows more accurate information regarding the prevalence, which can help to design more specific control programs. We apply this proposed model to data from the country of Venezuela for two periods, 1961–1971, and 1961–1991 taking into account real demographic data for these periods.

Results

Numerical computer simulations are presented to show the suitability of the age-structured model to explain the real data regarding prevalence of Chagas disease in each of the age groups. In addition, a numerical simulation varying the death rate of the vector is done to illustrate prevention and control strategies against Chagas disease.

Conclusion

The proposed model can be used to determine the effect of control strategies in different age groups.     

Climatic droplet keratopathy: an old disease in new clothes

Climatic droplet keratopathy (CDK) is an acquired and potentially handicapping cornea degenerative disease that is highly prevalent in certain rural communities around the world. It predominantly affects males over their forties. It has many other names such as Bietti's band‐shaped nodular dystrophy, Labrador keratopathy, spheroidal degeneration, chronic actinic keratopathy, oil droplet degeneration, elastoid degeneration and keratinoid corneal degeneration. CDK is characterized by the haziness and opalescence of the cornea's most anterior layers which go through three stages with increasing severity. Globular deposits of different sizes may be histopathologically observed under the corneal epithelium by means of light and electron microscopy. The coalescence and increased volume of these spherules may cause the disruption of Bowman's membrane and the elevation and thinning of the corneal epithelium. The exact aetiology and pathogenesis of CDK are unknown, but they are possibly multifactorial. The only treatment in CDK advanced cases is a corneal transplantation, which in different impoverished regions of the world is not an available option. Many years ago, the clinical and histological aspects of this disease were described in several articles. This review highlights new scientific evidence of the expanding knowledge on CDK's pathogenesis which will open the prospect for new therapeutic interventions.     

Immune reconstitution and associated infections following axicabtagene ciloleucel in relapsed or refractory large B-cell lymphoma

CD19 chimeric antigen receptor T (CAR T)-cell therapy with axicabtagene ciloleucel (axi-cel) for relapsed or refractory (R/R) large B-cell lymphoma (LBCL) may lead to durable remissions, however, prolonged cytopenias and infections may occur. In this single center retrospective study of 85 patients, we characterized immune reconstitution and infections for patients remaining in remission after axi-cel for LBCL. Prolonged cytopenias (those occurring at or after day 30 following infusion) were common with ≥grade 3 neutropenia seen in 21 of 70 (30%) patients at day 30 and persisting in 3 of 31 (9.7%) patients at 1 year. B cells were undetectable in 30 of 34 (88.2%) patients at day 30, but were detected in 11 of 19 (57.9%) at 1 year. Median immunoglobulin G levels levels reached a nadir at day 180. By contrast, CD4 T cells decreased from baseline and were persistently low with a median CD4 count of 155 cells/mL at 1 year after axi-cel (n=19, range: 33– 269). In total, 23 of 85 (27.1%) patients received intravenous immunoglobulins after axi-cel, and 34 of 85 (40%) received granulocyte-colony stimulating factor. Infections in the first 30 days occurred in 31 of 85 (36.5%) patients, of which 11 of 85 (12.9%) required intravenous antibiotics or hospitalization (“severe”) and were associated with cytokine release syndrome, neurotoxicity, tocilizumab use, corticosteroid use, and bridging therapy on univariate analyses. After day 30, seven severe infections occurred, with no late deaths due to infection. Prolonged cytopenias are common following axi-cel therapy for LBCL and typically recover with time. Most patients experience profound and prolonged CD4 T-cell immunosuppression without severe infection.     

Comparable long-term outcomes between DAS28-ESR remission criteria and ACR/EULAR definitions in patients with established rheumatoid arthritis

Clinical Rheumatology - To compare long-term clinical, immunological, and radiographic outcomes between five sets of remission criteria (four clinical and one ultrasound (US)-based) in a cohort of...     

Mayan alleles of the HLA-DRB1 major histocompatibility complex might contribute to the genetic susceptibility to systemic lupus erythematosus in Mexican patients from Tapachula,Chiapas

Clinical Rheumatology - Systemic lupus erythematosus (SLE) is the prototypic autoimmune disease that disrupts numerous immunity mechanisms with the potential to exert damage to any organ or tissue....     

Endocardite por Trichosporon beigelii 11 anos após cirurgia de troca valvar mitral

Trichosporon beigelii is a non‐pathogenic fungus that can however become an opportunist agent of disseminating and potentially fatal infections, especially in immunocompromised patients. In the literature, there are only 11 published cases of infective endocarditis due to T. beigelii. Most of these cases involved immunocompetent individuals and the main risk factor was the presence of a prosthetic valve. The longest interval between surgery and endocarditis was eight years. In the present study, a case of prosthetic valve endocarditis due to T. beigelii is reported in an immunocompetent patient 11 years after mitral valve replacement. As with similar cases, low clinical suspicion and negative blood cultures delayed the beginning of antifungal therapy and cardiac surgery. Considering the high mortality and severity of T. beigelii endocarditis, it should be considered when there is a prosthetic valve infection with negative blood cultures, irrespective of the time elapsed since the previous surgery.