Studies of the Human Microbiome in Clinical Center Patients

Background: \- The intestines, mouth, and skin all contain billions of bacteria and some fungi. Every person s body contains microorganisms like these. They normally do not make people sick. Researchers are interested in how these microorganisms change when a person is hospitalized. They want to find out if changes take place because of the hospitalization (such as treatments used or changes in medical condition) or because of a person s biology (such as their immune system). Objectives: \- To understand which microorganisms are most likely to spread through hospitals and what affects that spread. Eligibility: \- People 2 years of age and older who are going to be inpatients at the National Institutes of Health Clinical Center (NIHCC) for at least 48 hours. Design: * Clinicians will take samples from participants up to once a day for as long as they are hospitalized at NIHCC. * Samples will be taken with a swab, from the rectal area, groin, throat, and armpit, and possibly other areas. * Participants may give a stool sample or be asked to spit into a cup. * Clinicians will collect some information from participants medical records. They may request some samples of tissue that are left over from procedures already scheduled at NIHCC. * After participants leave the NIHCC, samples may be taken when they return for follow-up visits from their hospitalization, for up to 2 years. They will not have to return as a follow-up for this study only.

The goal of this protocol is to explore changes to microbial communities during the course of hospitalcare, and to determine the extent to which these alterations affect whether hospitalized patients become colonized with healthcare-associated organisms. The study enables collection of clinical specimens and associated medical data to evaluate the natural history, epidemiology, and genomics of patients who might become colonized or infected with a multidrug-resistant organism. Biological specimens including stool, sputum, and swabs will be taken from Clinical Center inpatients at least 2 years of age as frequently as daily through discharge, and at follow-up visits for up to 2 years from the date of enrollment. To understand possible pathogen colonization and infection of hospitalized patients, this protocol will assess the full complement of the microbial-host-environmental contributions including: (1) microbial genome and community;(2) patient s genotype, underlying medical condition, medical treatment; and (3) hospital practices and environment.

* INCLUSION CRITERIA: Individuals must meet the following inclusion criteria to participate in the study: * Be inpatients in the NIH CC with an expected hospitalization of at least 48 hours beyond the date of referral. * Be 2 years of age or older * Allow storage of tissue samples for future analyses. * Allow genetic testing of body fluids, and tissue specimens. EXCLUSION CRITERIA: A patient will not be eligible if he/she has any condition which, in the investigator s opinion, places the patient at undue risk by participating in the study.