Plasma Concentrations of Amoxicillin Administered in High-doses During the First Week of Treatment (MAX-AMOX)

Study Overview
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Brief Summary
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Amoxicillin is the most prescribed antibiotic in France. High dose intravenous amoxicillin, (dosage greater than or equal to 150 mg / kg / day or 12 g per day for patients over 80 kg) is used in the treatment, in particular, of infectious streptococcal endocarditis. oral, streptococci gallolyticus and enterococci, infections of the central nervous system with sensitive germs including Streptococcus pneumoniae and Listeria monocytogenes, osteo articular infections. The dose-related adverse effects of this antibiotic are nephrological (crystalluria may lead to acute renal failure) and neurologic. Recently, the number of amoxicillin crystalluria reported to pharmacovigilance centers has increased, having led the National Agency of drug and health products safety (ANSM) to recommend the determination of the residual level of amoxicillin during the first week of treatment of these patients. Nevertheless, there is no precise therapeutic target in patients treated with high dose amoxicillin except in the context of critical care. The authors suggest the interest of a target between 4 and 10 times the minimum inhibitory concentration (MIC) based on in vitro efficacy studies, and retrospective observations of toxicity cases.

Detailed Description
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Patients will be followed for 8 days. After inclusion, (day of the introduction of high-dose amoxicillin treatment), the residual amoxicillin plasma concentrations will be determined at Day1, Day4 +/- 1 day and Day7 +/- 1 day of the start of treatment. A urine collection will be performed the same day to search for crystalluria and measure the pH and urinary density. In case of KDIGO (Kidney Disease Improving Global Outcomes) 2 or 3 stage renal failure or neurological signs compatible with overdose, residual amoxicillin and crystalluria and urinary density and urinary pH will be measured during the day of discovery of renal failure. In the case of KDIGO stage 1 kidney failure, a residual level of amoxicillin and a crystalluria search and the measurement of urinary density and urinary pH will be carried out the following day, when serum creatinine is checked according to usual practices. At day 7 the clinical and infectious biological evolution of the patient will be collected.

Official Title
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Plasma Concentrations of Amoxicillin Administered in High-doses During the First Week of Treatment : Intra- and Inter-individual Variability, Factors Associated With Overdose and Adverse Events

Conditions
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Infection, Bacterial

Intervention / Treatment
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* Drug: Amoxicillin


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Major patient, male or female, who has a bacterial infection requiring high dose intravenous amoxicillin antibiotic therapy (greater than or equal to 150 mg / kg / day with a maximum of 12 grams per day or 12 grams per day for patients over 80 kg), according to ANSM recommendations. Able to provide informed consent to participate. Covered by a Social Security scheme. Exclusion Criteria: Pregnant, breastfeeding, or likely to be pregnant women and in the absence of a negative pregnancy test (blood HCG beta). Patients under guardianship, curatorship, deprived of liberties or subject to a safeguard of justice. Septic shock justifying treatment with pressurized amines. Patient under ventilatory or circulatory support. Patients on dialysis at Baseline or with a creatinin clearance less than or equal to 30mL / min Refusal of participation Hypersensitivity to the active substance, to penicillins. History of a severe immediate hypersensitivity reaction (e.g. anaphylaxis) to another beta-lactam (e.g. cephalosporin, carbapenem or monobactam)

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Patient reveiving amoxycillin<br>all patient included in this study | Drug: Amoxicillin<br>* dosage of plasma concentration of amoxicillin<br>* Other names: amoxicillin treatment;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Residual plasma concentrations of administered in high doses amoxicillin | research of Residual plasma concentrations of amoxicillin | Day 7 | 
| Residual plasma concentrations of administered in high doses amoxicillin | research of Residual plasma concentrations of amoxicillin | Day 4 | 
| Residual plasma concentrations of administered in high doses amoxicillin | research of Residual plasma concentrations of amoxicillin | Day 1 | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| search for cystalluria, description of crystals, and infrared spectropscopy to determine crystals composition | research in fresh morning urine sample, examined by microscope then infrared spectroscopy in case of crystalluria | Day 7 | 
| search for cystalluria, description of crystals, and infrared spectropscopy to determine crystals composition | research in fresh morning urine sample, examined by microscope then infrared spectroscopy in case of crystalluria | Day 4 | 
| search for cystalluria, description of crystals, and infrared spectropscopy to determine crystals composition | research in fresh morning urine sample, examined by microscope then infrared spectroscopy in case of crystalluria | Day 1 | 
| proportion of residual plasma concentrations above 10 minimal inhibitory concentration (MIC) | plasma concentrations on blood sample | day 7 | 
| proportion of residual plasma concentrations above 10 minimal inhibitory concentration (MIC) | plasma concentrations on blood sample | day 4 | 
| proportion of residual plasma concentrations above 10 minimal inhibitory concentration (MIC) | plasma concentrations on blood sample | day 1 | 
| density of urines in g/mL | research in fresh morning urine sample | Day 7 | 
| pH of urines | research in fresh morning urine sample | Day 7 | 
| density of urines in g/mL | research in fresh morning urine sample | Day 4 | 
| pH of urines | research in fresh morning urine sample | Day 4 | 
| density of urines in g/mL | research in fresh morning urine sample | Day 1 | 
| pH of urines | research in fresh morning urine sample | Day 1 | 
| confusional state | Glasgow coma scale | Day 1 | 
| confusional state | Glasgow coma scale | Day 4 | 
| confusional state | Glasgow coma scale | Day 7 | 
| encephalitic signs | focal neurological signs | Day 1 | 
| encephalitic signs | focal neurological signs | Day 4 | 
| encephalitic signs | focal neurological signs | Day 7 | 
| epilepsy | abnormal movement disorders, seizures and status epilepticus | Day 1 | 
| epilepsy | abnormal movement disorders, seizures and status epilepticus | Day 4 | 
| epilepsy | abnormal movement disorders, seizures and status epilepticus | Day 7 | 
| age associated with evolution of amoxicillin plasma concentrations | in years | Day 0 | 
| body mass index associated with evolution of amoxicillin plasma concentrations | weight in kg and height in meters will be combined to report BMI in kg/m^2 | Day 0 | 
| renal function at treatment initiation associated with evolution of amoxicillin plasma concentrations | CKD EPI clearance, based on serum creatinine in µmol/L | Day 0 | 
| renal function impairment during treatment | stage of acute kidney injury (based on KDIGO guidelines using variation of serum creatinine in µmol/L compared with baseline, and measure of urine output) | Day 1 | 
| renal function impairment during treatment | stage of acute kidney injury (based on KDIGO guidelines using variation of serum creatinine in µmol/L compared with baseline, and measure of urine output) | Day 4 | 
| renal function impairment during treatment | stage of acute kidney injury (based on KDIGO guidelines using variation of serum creatinine in µmol/L compared with baseline, and measure of urine output) | Day 7 | 
| germ involved | full name of bacteria | Day 0 | 
| MIC of germ | MIC in mg/L | Day 0 | 
| site of infection | infected organs | Day 0 | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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amoxycillin, drug kinetics, drug toxicity, crystalluria