Toxoplasmosis

Researchers are studying how eosinophils, a type of white blood cell, become activated and their role in immune reactions. Eosinophils often increase with allergies, asthma, parasitic infections, some autoimmune diseases, and rarely tumors, a condition called eosinophilia. While usually without symptoms, eosinophilia can sometimes cause swelling, itching, lung problems, heart disease, or nerve damage due to toxic substances released by these cells. Participants with eosinophil counts above 750/ml or abnormal eosinophil buildup in tissues or skin will have thorough medical exams, blood tests, and possibly additional tests based on age and symptoms. This observational study does not offer experimental treatments but monitors clinical responses and collects blood, bone marrow, tissue, and fluid samples for research. Follow-up includes yearly evaluations and may involve bone marrow biopsies, genetic testing, and leukapheresis for adults. Participants will be involved in detailed clinical evaluations at baseline and annually, with sample collections to study disease mechanisms and immune responses. The study aims to identify causes, biomarkers, and treatment effects on eosinophils. Safety monitoring includes standard care for those needing treatment, while research focuses on immune cell behavior, genetic factors, and long-term effects. Participation duration varies per individual, with ongoing assessments of disease activity and patient-reported outcomes.

Researchers are conducting a nationwide observational study in Denmark to track and understand infections of the central nervous system (CNS) among adults aged 18 years and older. This study systematically registers clinical characteristics and outcomes of all community-acquired CNS infections diagnosed or treated at infectious disease departments across the country since January 1, 2015. The aim is to monitor trends in infections such as bacterial meningitis, viral meningitis, encephalitis, brain abscess, neuroborreliosis, and neurosyphilis, among others. The study involves collecting detailed information on diagnosis at admission, symptoms, timing and type of diagnostic tests like lumbar puncture and cranial imaging, and treatments given. These treatments and diagnostic procedures are determined by local physicians and are not standardized across sites. The study ensures data quality through regular case reviews and annual checks of hospital records using specific diagnosis codes to identify CNS infection cases. Participants are monitored for outcomes using the Glasgow Outcome Scale at various time points depending on the infection type, such as 2 weeks for neurosyphilis and 8 weeks for brain abscess. Data on timing of hospital admission, diagnostic procedures, and antibiotic treatment are collected from hospital records. The study's main measure is the yearly incidence of CNS infections, capturing clinical course and patient outcomes to improve understanding of these serious infections over time.

Toxoplasma gondii infects over one third of the global population, with cerebral toxoplasmosis being a serious opportunistic infection especially in HIV patients. This infection can lead to high mortality rates due to brain swelling caused by mass lesions. While steroids are recommended to reduce brain edema, the best dose and duration of steroid use in this condition have not been clearly evaluated, and their safety in immunodeficient patients remains uncertain. This clinical trial is studying the use of dexamethasone, a strong steroid with a long half-life, as an additional treatment alongside standard anti-toxoplasmosis medications. Participants will be randomly assigned to receive either dexamethasone intravenously at 20 mg daily for 7 days or a placebo (normal saline) for the same duration. All patients will continue receiving standard oral anti-toxoplasmosis therapy according to national guidelines. During the study, researchers will monitor participants for up to 90 days to assess mortality rates as the primary outcome. They will also evaluate neurological status, cognitive function, brain imaging changes, and any serious side effects related to the study drug. The total participation involves close medical monitoring and multiple assessments to understand the effects and safety of dexamethasone in this condition.

Researchers are studying the natural history and treatment of leishmanial infections in patients aged 3 to 100 years. The study aims to better understand leishmaniasis, improve diagnostic tests, and observe how different species and host factors affect disease resistance and relapse. The National Institute of Allergy and Infectious Diseases (NIAID) is leading this observational research. Patients suspected or known to have leishmaniasis will undergo routine blood tests and biopsies tailored to the infection type: cutaneous, mucocutaneous, or visceral. Treatment varies by infection type and may include medications like Pentostam, amphotericin B, itraconazole, or ketoconazole with different dosing schedules and administration methods such as infusions or oral pills. Some patients may have skin tests similar to tuberculin testing, and treatments involve monitoring through blood draws, electrocardiograms, and urinalysis. Participants may have photographs taken and provide extra blood samples for research. Follow-up visits depend on the infection type, ranging from short-term (2 weeks to 3 months) for cutaneous cases to indefinite routine evaluations every 3 to 6 months for mucocutaneous and visceral infections. Researchers will assess clinical and immune responses, treatment safety and effectiveness, and collect genetic and immune data over time to understand infection outcomes.

Researchers are studying uveitis, an eye condition, to better understand its causes and the underlying disease mechanisms. This observational study is focused on collecting genetic information from patients with uveitis, including those with infectious forms like toxoplasmosis retinochoroiditis and herpes-associated retinitis. The goal is to analyze DNA to identify genetic mutations or associations linked to the condition. Participants with uveitis will provide blood samples, from which DNA will be isolated and sequenced. The study does not involve treatment or medication but focuses on gathering genetic data from both infectious and non-infectious uveitis patients. The study duration includes a follow-up period of 5 years to observe outcomes related to non-infectious and infectious uveitis. During the study, participants will be involved in blood sample collection for genetic analysis. Researchers will monitor the progression of uveitis over five years to assess genetic links and disease patterns. The study includes participants aged 6 years and older, and healthy volunteers may also participate. Data collected will help improve understanding of uveitis and its genetic factors.

Researchers are studying patients with filarial infections, which are caused by parasitic worms transmitted by mosquito bites. These infections can range from no symptoms to serious issues like swelling, allergic lung problems, skin rashes, eye inflammation leading to blindness, and heart disease. The study aims to explore the immune response to these infections, including how susceptible people are, how the disease develops, and how patients respond to treatment. Participants diagnosed with or suspected of having filarial infections will undergo standard medical tests to identify the specific parasite type. Depending on the infection, tests may include lung, skin, or heart examinations, and some may have a skin biopsy or bronchoalveolar lavage if medically necessary. Treatment will follow standard care using diethylcarbamazine or ivermectin based on the infection type. Additional research procedures include extra blood draws, urine collections, skin allergy tests, and leukapheresis for immune cell collection in adults. During the study, participants will have more frequent follow-up visits than usual, including physical exams and blood tests. Researchers will collect blood and serum samples to study immune responses and monitor how patients clinically and immunologically respond to treatment over time. The main outcome is to understand the factors affecting infection susceptibility, disease progression, and treatment response, with long-term observation planned for up to 10 years.

Researchers are collecting information about patients with various infectious diseases to create a detailed database and biobank. This observational study focuses on illnesses such as bloodstream infections, central nervous system infections, bone and joint infections, endovascular infections, sexually transmitted infections, HIV infection, and emerging infectious diseases. The goal is to understand the clinical, laboratory, imaging, and microbiological features as well as treatment approaches, and to study factors affecting treatment success and disease outcomes. Participants will provide biological samples like blood, cerebrospinal fluid, and urine at the start of their infectious disease diagnosis. Data and samples will be collected at baseline, end of treatment, and six months later, or yearly for HIV patients. Additional collections may occur depending on disease progression or treatment changes. The study will record clinical scores, laboratory results, imaging, treatment details, drug levels, and outcomes including mortality and complications. Participants will be monitored through clinical and laboratory assessments at several time points including baseline, end of treatment, and follow-up visits. Researchers will use these data to analyze disease characteristics, treatment responses, and outcomes over time. The study aims to identify biomarkers, predictors of cure, and factors influencing mortality and complications. Participation involves donating samples and sharing medical information, with follow-up lasting at least six months or longer for some conditions.

Researchers are comparing two ways of giving polymyxin B to treat severe brain infections caused by carbapenem-resistant Gram-negative bacteria (CRGNB). The study looks at whether injecting the drug directly into the brain alone or combining this with an intravenous infusion works better to clear the infection and improve patient outcomes. It also measures the levels of polymyxin B in the cerebrospinal fluid (CSF) to understand how the drug acts in the body. Participants are divided into two groups. One group receives polymyxin B directly into the brain without an IV infusion. The other group receives polymyxin B both directly into the brain and through an IV infusion. All participants have an external ventricular drain to continuously drain CSF, and they must have been receiving polymyxin B treatment for at least five days before joining. During the study, researchers will monitor the 30-day mortality rate, bacterial clearance in the CSF at baseline, 1 week, 2 weeks, and 30 days after starting treatment, and the clinical cure rate at the end of treatment and 30 days afterward. Participants will be followed closely to assess how well the infection clears and to check safety. The study will continue until December 2026.

Researchers are evaluating whether adding the Karius Spectrum12 plasma test to standard diagnostic tests helps diagnose infections faster in immunocompromised adults seen in outpatient settings. The study compares usual care testing alone to usual care plus the Karius Spectrum test, which detects many types of microbial pathogens from a blood sample. The trial includes two groups: solid organ transplant patients and those with hematologic malignancies or related treatments. Participants are randomly assigned to receive either the Karius Spectrum test results alongside usual care or usual care testing alone. The Karius Spectrum test analyzes microbial cell-free DNA in plasma to identify over 1,000 pathogens, including bacteria, viruses, fungi, and parasites. The study is designed as a basket trial to assess this testing approach across multiple high-risk immunocompromised populations with suspected infections. Participants provide a one-time blood sample within 24 hours of enrollment and are followed for 30 days to record illness information, usual care lab tests, treatments, and any adverse events. Researchers measure the time to identify a pathogen, start targeted treatment, antimicrobial therapy duration, and the proportion of patients receiving pathogen-directed therapy. Safety data are collected through day 30, with participant outcomes tracked in the outpatient setting including telehealth visits.

Toxoplasmosis is a common infection that can be severe enough to require intensive care, especially for people with weakened immune systems. This research aims to evaluate how different anti-infective treatments affect patients with severe forms of toxoplasmosis, including cerebral and disseminated types. It also seeks to identify clinical, biological, and prognostic differences based on the type of underlying immunosuppression in these patients. The study observes patients hospitalized in intensive care with confirmed toxoplasmosis diagnosed using polymerase chain reaction (PCR) tests from cerebrospinal fluid, blood, bronchoalveolar lavage, or bone marrow samples. It records the use of various treatment regimens such as oral pyrimethamine-sulfadiazine and intravenous treatments like trimethoprim-sulfamethoxazole or clindamycin combined with pyrimethamine. The study focuses on real-world management without altering treatments and includes patients with at least one organ failure. Participants will be monitored for outcomes including mortality rate in intensive care, hospital mortality, length of stay in intensive care, and duration of mechanical ventilation over an 11-year period. The study collects detailed clinical and biological information to better understand severe toxoplasmosis in immunocompromised patients. Data reuse is subject to patient consent, and the research is observational with no experimental interventions applied.