Current Clinical Microbiology Reports最新文献

Purpose of review: This study compares the survival and clinical profile of hospitalized adults with COVID-19 in two clinics in the city of Medellín, Colombia, with a prospective study with 198 patients in clinic A and 201 in clinic B. Comparisons were made with chi-square and Mann-Whitney U, factors associated with survival were identified with a Cox regression.

Recent findings: The proportion of deaths was 7.1% in clinic A with a mean survival of 51.9 days (95% CI = 45-59); in clinic B 13.9% of patients died with mean survival of 37.8 days (95% CI = 32-43). The most prevalent comorbidities were hypertension (41.6%), diabetes (23.8%), obesity (15.0%), hypothyroidism (13.0%), dyslipidemia (11.0%), and chronic lung disease (10.8%) with similar proportions in both clinics. There were also differences by the clinic in the most prevalent complications: bacterial pneumonia (18.8%), acute renal failure (14.3%), and encephalopathy (9.5%). There were no differences in the days of hospitalization, mechanical ventilation (clinic A 23.7% and clinic B 29.4%) and admission to the ICU (25.3% in A and 32.3% in B).

Summary: We evidence the heterogeneity of the survival and the clinical profile of the patients who are cared for by two institutions of the same city. These findings demonstrate the need to conduct unique studies for each institution, which poses a significant challenge for hospital epidemiology programs due to the impossibility of extrapolating evidence from other healthcare institutions and the need to implement personalized medicine programs given the clinical diversity of patients hospitalized for COVID-19.

Purpose of review: Herein, we provide a critical review of the clinical and translational research examining the relationship between viral and bacterial pathogens and Alzheimer's disease. In addition, we provide an overview of the biological pathways through which chronic infection may contribute to Alzheimer's disease.

Recent findings: Dementia due to Alzheimer's disease is a leading cause of disability among older adults in developed countries, yet knowledge of the causative factors that promote Alzheimer's disease pathogenesis remains incomplete. Over the past several decades, numerous studies have demonstrated an association of chronic viral and bacterial infection with Alzheimer's disease. Implicated infectious agents include numerous herpesviruses (HSV-1, HHV-6, HHV-7) and various gastric, enteric, and oral bacterial species, as well as Chlamydia pneumonia and multiple spirochetes.

Summary: Evidence supports the association between multiple pathogens and Alzheimer's disease risk. Whether these pathogens play a causal role in Alzheimer's pathophysiology remains an open question. We propose that the host immune response to active or latent infection in the periphery or in the brain triggers or accelerates the Alzheimer's disease processes, including the accumulation of amyloid-ß and pathogenic tau, and neuroinflammation. While recent research suggests that such theories are plausible, additional longitudinal studies linking microorganisms to Aß and phospho-tau development, neuroinflammation, and clinically defined Alzheimer's dementia are needed.

Purpose of review: Malaria is a disease caused by parasites that reside in host red blood cells and use hemoglobin as a nutrient source. Heme released by hemoglobin catabolism is modified by the parasite to produce hemozoin (HZ), which has toxic effects on the host. Experimentation aiming to elucidate how HZ contributes to malaria pathogenesis has utilized different preparations of this molecule, complicating interpretation and comparison of findings. We examine natural synthesis and isolation of HZ and highlight studies that have used multiple preparations, including synthetic forms, in a comparative fashion.

Recent findings: Recent work utilizing sophisticated imaging and detection techniques reveals important molecular characteristics of HZ synthesis and biochemistry. Other recent studies further refine understanding of contributions of HZ to malaria pathogenesis yet highlight the continuing need to characterize HZ preparations and contextualize experimental conditions in the in vivo infection milieu.

Summary: This review highlights the necessity of collectively determining what is physiologically relevant HZ. Characterization of isolated natural HZ and use of multiple preparations in each study are recommended with application of in vivo studies whenever possible. Adoption of such practices is expected to improve reproducibility of results and elucidate the myriad of ways that HZ participates in malaria pathogenesis.