An interventional study of Blood draw and muscle biopsy in Hypotonia-Cystinuria Syndrome, Muscle Hypotonia and Healthy Volunteers, sponsored by Universitaire Ziekenhuizen KU Leuven. Active, not recruiting at 1 site in Belgium. Open to participants aged Up to 40 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2024-07-16.
Sponsored by Universitaire Ziekenhuizen KU Leuven · Not applicable, Interventional, and Diagnostic
Evaluation of PREPL activity in healthy controls and known or possible PREPL deficient patients
PREPL is defective in hypotonia cystinuria syndrome and in isolated PREPL deficiency. The investigators have constructed a blood test to evaluate PREPL activity in patients with possible PREPL deficiency.
The study will determine normal values for age (0-18) for PREPL activity in blood.
Also, patients with a clinical phenotype that overlaps with PREPL deficiency (including patients with known primary PREPL deficiency and Prader-Willi syndrome) will be evaluated for PREPL activity in blood.
A last part of the study will involve muscle biopsies during elective anesthesia/surgery for other reasons. There will be 2 groups: patients without signs of PREPL deficiency undergoing surgery (controls) and patients with Prader-Willi syndrome undergoing anesthesia or surgery (patients). The control group will be age-matched to the hypotonia group. In the muscle biopsies, PREPL activity and expression will be evaluated.
66 studies on the registry are indexed under Muscle Hypotonia; 14 are open to participants now.
This study's planned enrollment of 125 is above the median of 49 across 43 interventional studies indexed under Muscle Hypotonia.
Browse Muscle Hypotonia studies →Universitaire Ziekenhuizen KU Leuven is the lead sponsor of 963 studies on the registry; 267 are open to participants now.
Of its 5 completed or terminated interventional studies of FDA-regulated products, 0 (0%) have results posted.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
A biopsy takes a small piece of tissue to examine. “Archival tissue” is a sample already taken, for example at diagnosis, and kept by the hospital.
Whether a stored sample will do depends on when it was taken, how much there is and what the study needs. Ask whether the study accepts your stored sample or needs a new biopsy.
Contraindication
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Biopsy and archival tissue
A biopsy takes a small piece of tissue to examine. “Archival tissue” is a sample already taken, for example at diagnosis, and kept by the hospital.
Whether a stored sample will do depends on when it was taken, how much there is and what the study needs. Ask whether the study accepts your stored sample or needs a new biopsy.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Patients on routine postinfectious control, blood draw
Procedure: Blood draw
Patients with primary PREPL deficiency, blood draw
Procedure: Blood draw
Patients with Prader-Willi syndrome, blood draw
Procedure: Blood draw
Patients with symptoms overlapping with primary PREPL deficiency (like hypotonia, growth hormone deficiency, obesity), blood draw
Procedure: Blood draw
Patients without hypotonia, growth hormone deficiency, obesity, undergoing elective surgery, muscle biopsy from the surgical site and blood draw
Procedure: Blood draw · Procedure: muscle biopsy
Patients with Prader-Willi syndrome undergoing elective anesthesia or surgery, muscle biopsy (from surgical site if applicable) and blood draw
Procedure: Blood draw · Procedure: muscle biopsy
Blood draw
Muscle biopsy during planned anesthesia/surgery
PREPL activity (ng active PREPL/g protein) normal values in blood
normal values for PREPL activity
Time frame: 3 months
PREPL activity in patients with Prader Willi syndrome compared to activity in normal controls
Comparison of PREPL activity in blood and muscle between above mentioned groups
Time frame: 3 months
PREPL activity in patients with primary PREPL deficiency compared to activity in normal controls
Comparison of PREPL activity in blood between above mentioned groups
Time frame: 3 months
PREPL activity in patients with muscle weakness/obesity/growth hormone deficiency compared to activity in normal controls
exploratory evaluation
Time frame: 3 months
The record gives a start of Oct 2014, a primary completion of Jan 2025 and a completion of Jan 2025. It does not say whether these dates are actual or estimated.
How these figures are worked out, and which studies are left out of them.
This study is active, not recruiting, as verified in Jul 2024. You cannot join it, but the record below documents what was studied.
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