Clinical Research Directory

Modeling Host-Pathogen Interaction Using Lymphoid Organoids

Background: Staphylococcus aureus (S.aureus) are bacteria that can make people sick. Sometimes, an S. aureus infection can develop inside the spine; these infections can lead to paralysis and death. Researchers do not know how S. aureus interacts with a person s cells to cause infections in the spine. Objective: To learn how S. aureus interacts with cells in the body using tissues from tonsils discarded after standard surgery to remove them. Eligibility: People aged 2 years and older who are scheduled to have their tonsils removed. Design: Researchers will select participants for the study based on review of their existing medical records, including results of blood tests; any imaging scans, including x-rays; and reports about tissue specimens. Participants will answer questionnaires about their health and past infections. They can do this online or on paper. Participants will collect a nasal swab 1 week before their surgery. They will be given a tool that looks like a long cotton swab. They will twirl it around inside their nose. The swab will pick up cells and fluids that will be used for research. After their surgery, the participant s surgeon will save samples of tonsil tissue. The surgeon will send these tissue samples and the nasal swab to researchers at the NIH. These tissues and the swab will be used in studies to help researchers understand how S. aureus interacts with cells in the body. They hope these studies will help them find better ways to treat S. aureus infections.

Population Pharmacokinetic Model of Rifampicin in Staphylococcal Osteoarticular Infections

Staphylococcal osteoarticular infections (OAIs), including prosthetic joint infections and chronic osteomyelitis, represent a major cause of morbidity. Rifampicin is a key bactericidal antibiotic effective against staphylococcal biofilm. However, its pharmacokinetics exhibit substantial inter-individual variability due to complex hepatic metabolism and drug interactions. Currently, no prospective population pharmacokinetic (PopPK) model of rifampicin combined with levofloxacin or ciprofloxacin exists in patients with OAIs. Objectives: The primary objective of this study is to develop a population pharmacokinetic model of oral rifampicin in patients undergoing medico-surgical treatment for staphylococcal osteoarticular infections. Secondary objectives include evaluating the pharmacokinetics of the partner antibiotic (levofloxacin or ciprofloxacin), investigating the correlation between antibiotic exposure metrics (AUC, Cmax, AUC/MIC) and clinical/biological tolerance, and assessing 1-year infection relapse-free survival and resistance emergence. Study Design: Prospective, single-center, interventional study with minimal risks and constraints (RIPH 2) involving 40 participants recruited at the Reference Center for Complex Osteoarticular Infections (CRIOAC).

Standard Treatment Associated With Phage Therapy Versus Placebo for Diabetic Foot Ulcers Infected by S. Aureus

The primary objective of this study is to compare the efficacy of standard treatment associated with a topical anti-staphylococcal bacteriophage cocktail versus standard treatment plus placebo for diabetic foot ulcers monoinfected by methicillin-resistant or susceptible S. aureus (MRSA or MSSA) as measured by the relative reduction in wound surface area (%) at 12 weeks.

Unbound Cloxacillin Concentrations During Continuous Infusion

Cloxacillin is the first-line choice for the treatment of severe infections caused by the bacterium Staphylococcus aureus in Sweden. Over the past year, cloxacillin is increasingly administred through continuous infusion. In this study, the free (unbound) concentration of cloxacillin when administered as a continuous infusion will be measured to ensure that the free concentration is neither too high nor too low. A PK/PD model will be developed to predict which dosage of cloxacillin is appropriate for an individual based on age, gender, kidney function, and serum-protein level.

Adjunctive Clindamycin for the Treatment of Skin and Soft Tissue Infections, a Randomized Controlled Trial

This is an exploratory study to evaluate the effect of adjunctive clindamycin in the treatment of skin and soft-tissue infections due to Staphylococcus aureus in patients from Sierra Leone. The study hypothesizes that clindamycin, when added to routine treatment, will lead to a more rapid clinical resolution and less frequent recurrences of infection.