Spatial Characteristics of Colonic Mucosa-Associated Gut Microbiota in Humans.

Limited data exist on the spatial distribution of the colonic bacteria in humans. We collected the colonic biopsies from five segments of 27 polyp-free adults and collected feces from 13 of them. We sequenced the V4 region of the bacterial 16S rRNA gene using the MiSeq platform.

An Unusual Cause of Acute Pancreatitis in a Liver Transplant Recipient.

Posttransplant lymphoproliferative disorder (PTLD) in liver transplant recipients is relatively uncommon, with an estimated incidence of 1%-3%. Retrospective reviews of liver transplant recipients have mainly reported posttransplant lymphoproliferative disorder affecting the liver, gastrointestinal tract, or lymph nodes. In this case report, we describe a 45-y-old female with a history of deceased donor liver transplantation for autoimmune hepatitis who had recurrent hospital admissions for acute pancreatitis.

Immunosuppressive Drug Levels in Liver Transplant Recipients: Impact in Decision Making.

To prevent rejection, liver transplant providers largely base their management decisions on their clinical impression and pharmacokinetics. Clinical impression relies on assessing graft function, liver enzymes, and biopsy. High immunosuppressive drug levels, although minimizing rejection, are related to significant side effects such as nephrotoxicity and metabolic syndrome, contributing to long-term morbidity and mortality.

Dietary Nutrients Involved in One-Carbon Metabolism and Colonic Mucosa-Associated Gut Microbiome in Individuals with an Endoscopically Normal Colon.

One carbon (1C) metabolism nutrients influence epigenetic regulation and they are supplied by diet and synthesized by gut microbiota. We examined the association between dietary consumption of methyl donors (methionine, betaine and choline) and B vitamins (folate, B2, B6, and B12) and the community composition and structure of the colonic mucosa-associated gut microbiota determined by 16S rRNA gene sequencing in 97 colonic biopsies of 35 men. We used the food frequency questionnaire to assess daily consumption of nutrients, and the UPARSE and SILVA databases for operational taxonomic unit classification.

Pathogenesis of Alcoholic Liver Disease: An Update.

Apart from the classic knowledge that ethanol mediates its hepatotoxicity through its metabolism to acetaldehyde, a well-known hepatotoxic molecule, recent research has elucidated several key mechanisms that potentiate ethanol's damage to the liver parenchyma, such as generation of free radicals, activation of Kupffer cells, and alterations to the human bacterial and fungal microbiome. Genetic studies have suggested the role of PNPLA3 and TM6SF2 gene mutations in the progression of alcoholic liver disease.

Antibody Response to Hepatitis B Virus Vaccine is Impaired in Patients With Inflammatory Bowel Disease on Infliximab Therapy.

Background: Studies have demonstrated an association between anti-TNF/immunomodulator agents used in inflammatory bowel disease (IBD) and impaired hepatitis B virus (HBV) vaccine immunogenicity, but little data exist on whether specific medication types affect protective HBsAb titers. Our aim was to analyze this association.

Methods: This is a retrospective cohort study.

A multi-host approach for the systematic analysis of virulence factors in Cryptococcus neoformans.

A multi-host approach was followed to screen a library of 1201 signature-tagged deletion strains of Cryptococcus neoformans mutants to identify previously unknown virulence factors. The primary screen was performed using a Caenorhabditis elegans-C. neoformans infection assay.

The impact of antimicrobial resistance and aging in VAP outcomes: experience from a large tertiary care center.

Background: Ventilator associated pneumonia (VAP) is a serious infection among patients in the intensive care unit (ICU).

Methods: We reviewed the medical charts of all patients admitted to the adult intensive care units of the Massachusetts General Hospital that went on to develop VAP during a five year period.

Results: 200 patients were included in the study of which 50 (25%) were infected with a multidrug resistant pathogen.

Nocardiosis of the central nervous system: experience from a general hospital and review of 84 cases from the literature.

Central nervous system (CNS) nocardiosis is a rare disease entity caused by the filamentous bacteria Nocardia species. We present a case series of 5 patients from our hospital and a review of the cases of CNS nocardiosis reported in the literature from January 2000 to December 2011. Our results indicate that CNS nocardiosis can occur in both immunocompromised and immunocompetent individuals and can be the result of prior pulmonary infection or can exist on its own.

Fusarium infection: report of 26 cases and review of 97 cases from the literature.

Fusarium species is a ubiquitous fungus that causes opportunistic infections. We present 26 cases of invasive fusariosis categorized according to the European Organization for Research and Treatment of Cancer/Mycoses Study Group (EORTC/MSG) criteria of fungal infections. All cases (20 proven and 6 probable) were treated from January 2000 until January 2010.

Risk factors for invasive fungal disease after allogeneic hematopoietic stem cell transplantation: a single center experience.

Invasive fungal disease (IFD) is a major cause of morbidity and mortality after hematopoietic stem cell transplantation (HCT). We performed a retrospective review of 271 adults with a hematologic malignancy undergoing allogeneic HCT to determine the incidence of and risk factors for IFD and to examine the impact of IFD on nonrelapse mortality and overall survival. We defined IFD using standard criteria and selected proven and probable cases for analysis.

Central nervous system aspergillosis: a series of 14 cases from a general hospital and review of 123 cases from the literature.

Central nervous system (CNS) aspergillosis is a highly fatal infection. We review the clinical presentation, diagnosis, and outcome of this infection and present a case series of 14 consecutive patients with CNS aspergillosis admitted to Massachusetts General Hospital (MGH) from 2000 to 2011. We also review 123 cases reported in the literature during that time.

N-acetylglucosamine induces white-to-opaque switching and mating in Candida tropicalis, providing new insights into adaptation and fungal sexual evolution.

Pathogenic fungi are capable of switching between different phenotypes, each of which has a different biological advantage. In the most prevalent human fungal pathogen, Candida albicans, phenotypic transitions not only improve its adaptation to a continuously changing host microenvironment but also regulate sexual mating. In this report, we show that Candida tropicalis, another important human opportunistic pathogen, undergoes reversible and heritable phenotypic switching, referred to as the "white-opaque" transition.

Update on the epidemiology and management of cryptococcal meningitis.

Despite recent improvements in the diagnosis and treatment of cryptococcosis, cryptococcal meningitis is responsible for > 600,000 deaths/year worldwide. The aim of this work is to provide an update on the developments in its epidemiology and management. Understanding the pathogenesis of Cryptococcus has improved, and new insights for the virulence of the fungus and the host response have enabled scientists to design new ways to confront this infection.

Polymerase chain reaction-based assays for the diagnosis of invasive fungal infections.

Currently accepted fungal diagnostic techniques, such as culture, biopsy, and serology, lack rapidity and efficiency. Newer diagnostic methods, such as polymerase chain reaction (PCR)-based assays, have the potential to improve fungal diagnostics in a faster, more sensitive, and specific manner. Preliminary data indicate that, when PCR-based fungal diagnostic assays guide antifungal therapy, they may lower patient mortality and decrease unnecessary antifungal treatment, improving treatment-associated costs and avoiding toxicity.

Candida infection and colonization among trauma patients.

Background: Data on Candida infection among critically ill trauma patients are limited and not recently updated. Here we study the epidemiology and economic impact of Candida and examine potential risk factors for Candida infection in this population.

Methods: In this 5-year retrospective study, all severely injured patients with ≥4 days of intensive care unit stay were included, with the primary outcome being Candida infection.

Candida infection and colonization among non-trauma emergency surgery patients.

Background: Candida is a significant pathogen among critically ill patients. However, candidiasis among non-trauma emergency surgery (NTES) patients has not been previously investigated. Herein we describe the incidence of both colonization and infection from Candida and risk factors for invasive disease in this population.

Statin therapy and decreased incidence of positive Candida cultures among patients with type 2 diabetes mellitus undergoing gastrointestinal surgery.

Objective: To assess whether statin therapy decreases the incidence of cultures positive for Candida species among high-risk hospitalized patients with type 2 diabetes mellitus (DM).

Patients And Methods: We performed a retrospective cohort study analyzing the records of all patients with type 2 DM who were admitted to Massachusetts General Hospital for lower gastrointestinal tract surgery between January 1, 2001, and May 1, 2008. We defined statin exposure as the filling of at least 1 prescription of statins during the 6 months before hospitalization or during the current hospital stay.

The effect of cumulative length of hospital stay on the antifungal resistance of Candida strains isolated from critically ill surgical patients.

Fluconazole is the first line of therapy for the management of candidiasis. However, fluconazole-resistant strains pose an emerging challenge in everyday clinical practice. In this study, we sought to determine whether cumulative length of hospital stay (CLOS) is a predictive factor for the acquisition of non-susceptible Candida strains to fluconazole.