Drug-induced Crystalline NephropathyCRYSTALLINENCT07772752
Drug-induced Crystalluria in Sulfamethoxazole, High Dose Ciprofloxacin and High Dose Amoxicillin
A study testing Crystalluria examination in people with Drug-induced Crystalline Nephropathy and Drug-induced Crystalluria, run by Universitair Ziekenhuis Brussel at 1 site in Belgium.
Trial summary
This study examines in hospitalized patients, treated with sulfamethoxazole, high dose ciprofloxacin or high dose iv amoxicillin, the incidence of drug-induced urinary crystal formation and its association with acute kidney injury development. Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Drug-induced Crystalline Nephropathy, Drug-induced Crystalluria, Infections Treated With Sulfamethoxazole, High Dose Ciprofloxacin or High Dose iv Amoxicillin
- What is being tested?
- Crystalluria examination
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 290 participants
- Where
- 1 siteBelgium
- Study dates
- 8 Dec 2025to 31 Dec 2026
- Phase
- Interventional
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Age ≥ 18 years
- Able to give informed consent without the intervention of a legal representative
- Treatment with
- sulfamethoxazole/trimethoprim, with minimum dose of
- ≥ 800/160 mg q12h oral administration (PO) or intravenous administration (IV) for eGFR ≥ 30 ml/min
- ≥ 400/80 mg q12h OR or IV for eGFR < 30 ml/min OR
Show all 17Show fewer
- high dose ciprofloxacin, defined as
- ≥ 750 mg q12h PO or ≥ 400 mg q8h IV for eGFR ≥ 60 ml/min
- ≥ 750 mg q24h PO or ≥ 400 mg q12h IV for eGFR 15-59 m/min
- ≥ 750 mg q24h PO OR ≥ 400 mg q24h IV for eGFR < 15 ml/min
- OR
- high dose amoxicillin, defined as
- ≥ 2g q6h IV for eGFR ≥ 30 ml/min
- ≥ 2g q8h IV for eGFR 15-29 ml/min
- ≥ 2g q12h IV for eGFR < 15 ml/min
- Treatment for min 24 hours and sufficiently long to perform one crystalluria investigation as defined in the protocol
- Baseline renal function up to 72 hours prior to the start of antibiotic treatment available (evaluated by serum creatinine and eGFR (CKD-EPI)) for all study groups and additional serum urea for the sulfamethoxazole group).
Who cannot join
- Unable to give informed consent without the intervention of a legal representative
- No baseline renal function up to 72 hours prior to the start of antibiotic treatment available, evaluated by serum creatinine and eGFR (CKD-EPI)) for all study groups and additional serum urea for the sulfamethoxazole group.
- Treatment duration < 24 hours or insufficiently long to perform one crystalluria inves-tigation as defined in the protocol
- Patients treated with hemodialysis or peritoneal dialysis, anuric patients before start of antibiotic treatment
- Patients with urinary diversions
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
Belgium1 site, 1 recruiting
- Recruiting
Universitair Ziekenhuis Brussel
Brussels, 1090
Els Van de Perre, MD, 0032 2 477 60 55, els.vandeperre@uzbrussel.be
About this study
Official title: Drug-induced Crystalluria in Sulfamethoxazole, High Dose Ciprofloxacin and High Dose Amoxicillin Treatment: a Prospective Study
This study examines in hospitalized patients, treated with sulfamethoxazole, high dose ciprofloxacin or high dose iv amoxicillin, the incidence of drug-induced urinary crystal formation and its association with acute kidney injury development.
Read the detailed description
This is a prospective study which evaluates in hospitalized patients treated with sulfamethoxazole (po or iv), high dose ciprofloxacin (po or iv) or high dose iv amoxicillin, regardless the indication of the antibiotic treatment, the incidence of development of drug-induced urinary crystal formation. In addition, the association between development of AKI and the development of drug-induced crystalluria will be assessed for each of these antibiotics. Moreover, demographic, clinical and biochemical factors associated with the development of drug-induced crystalluria will be evaluated, as well as the timing of crystalluria development and potential AKI development.
In eligible patients who have provided informed consent first voided morning urine samples will be evaluated for the presence of drug-induced crystals by crystalluria examination at predefined moments, depending on the specific antibiotic treatment (day 2, 4, 6, 8 and 11 after start of antibiotic treatment for amoxicillin treatment, day 3 and 7 after start of antibiotic treatment for ciprofloxacin treatment, day 3, 7 and 11 after start of antibiotic treatment for sulfamethoxazole treatment). Renal function determination by serum creatinine in case of amoxicillin and ciprofloxacin treatment and by serum creatinine and serum urea in case of sulfamethoxazole treatment will be performed at baseline and other predefined moments after the start of antibiotic treatment, depending on the specific antibiotic treatment ( day 1-3, 4-7, 8-11 and 12-14 after the start of antibiotic treatment for amoxicillin treatment, day 3-7 and 8-12 after the start of antibiotic treatment for ciprofloxacin treatment, day 1-4, 5-9, 10-14 after the start of antibiotic treatment for sulfamethoxazole treatment). Occurrence of acute kidney injury will be evaluated. Demographic, clinical and biochemical data will be collected from the electronic medical records, including data on demographics, medical history, medical treatment, data on the antibiotic treatment including dosing and biochemical parameters, including baseline renal function renal function (serum creatinine and eGFR (CKD-EPI), serum urea), CRP. Patients will remain included up to 14 days of antibiotic treatment or until discharge, whatever comes first.
- Conditions
- Drug-induced Crystalline Nephropathy, Drug-induced Crystalluria, Infections Treated With Sulfamethoxazole, High Dose Ciprofloxacin or High Dose iv Amoxicillin
- Being tested
- Crystalluria examination
- Keywords
- crystalluria, drug-induced acute kidney injury, drug-induced crystalline nephropathy, amoxicillin, sulfamethoxazole, ciprofloxacin
- Medical subject headings
- Crystalluria
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Crystalluria examinationDiagnostic test
Crystalluria examination
| Study group | Role | What they receive |
|---|---|---|
| Antibiotic treatment | Other | Not described Receives: Diagnostic Test: Crystalluria examination |
What is being measured
The primary outcome is the main question the study is designed to answer.
Incidence of drug-induced crystalluria in patients treated with sulfamethoxazole
The presence of sulfamethoxazole-induced crystalluria will be evaluated by microscopic crystalluria examination in first voided morning urine samples on day 3, 7 and 11 after start of treatment and will be reported as a dichotomous parameter (present/absent).
Measured: Up to 11 days after start of treatment
Incidence of drug-induced crystalluria in patients treated with high dose ciprofloxacin
The presence of ciprofloxacin-induced crystalluria will be evaluated by microscopic cyrstalluria examination in first voided morning urine samples on day 3 and 7 after start of treatment and will be reported as a dichotomous parameter (present/absent).
Measured: Up to day 7 after start of treatment
Incidence of drug-induced crystalluria in patients treated with high dose iv amoxicillin
The presence of amoxicillin-induced crystalluria will be evaluated by microscopic cyrstalluria examination in first voided morning urine samples on day 2, 4, 6, 8 and 11 after start of treatment and will be reported as a dichotomous parameter (present/absent).
Measured: Up to 11 days after start of treatment
Incidence of AKI in patients treated with high dose iv amoxicillin
Acute kidney injury is defined as an increase in serum creatinine by ≥ 0.3 mg/dl within 48 hours or ≥ 1.5 times baseline within the prior 7 days. The occurrence of acute kidney injury will be performed by calculating the difference between serum creatinine at baseline and during antibiotic treatment at 4 different moments after start of antibiotic treatment, namely day 1-3, day 4-7, day 8-11 and day 12-14.
Measured: Up to 14 days after start of treatment
Secondary outcomes (7)
Incidence of AKI in patients treated with sulfamethoxazole
Acute kidney injury is defined as an increase in serum creatinine by ≥ 0.3 mg/dl within 48 hours or ≥ 1.5 times baseline in association with a concomitant rise of serum urea of 22 mg/dl within 48 hours or ≥ 1.5 times base-line within the prior 7 days. The occurrence of acute kidney injury will be performed by calculating the difference between serum creatinine and serum urea at baseline and during antibiotic treatment at 3 different moments after start of antibiotic treatment, namely day 1-4, day 5-9, day 8-11 and day 10-14.
Measured: Up to 14 days after start of treatment
Incidence of AKI in patients treated with high dose ciprofloxacin
Acute kidney injury is defined as an increase in serum creatinine by ≥ 0.3 mg/dl within 48 hours or ≥ 1.5 times baseline within the prior 7 days. The occurrence of acute kidney injury will be performed by calculating the difference between serum creatinine at baseline and during antibiotic treatment at 2 different moments after start of antibiotic treatment, namely day 3-7 and day 8-12. By this we will evaluated if the occurrence of ciprofloxacin-induced crystalluria is associated with an increased risk of incident AKI development in patients treated with high dose ciprofloxacin.
Measured: Up to 12 days after start of treatment
Identification of demographic, clinical and biochemical factors associated with the development of drug-induced crystalluria
Identification of demographic, clinical and biochemical factors associated with the development of drug-induced crystalluria by means of repeated measures logistic regression modelling
Measured: Up to 11 days after start of treatment for sulfamethoxazole, up to 7 days after start of treatment for ciprofloxacin, up to 11 days after start of treatment for high dose iv amoxicillin
Time interval between start of antibiotic treatment and development of sulfamethoxazole, ciprofloxacin and amoxicillin crystalluria
Measured: up to 11 days after start of treatment for sulfamethoxazole, up to 7 days after start of treatment for ciprofloxacin, up to 11 days after start of treatment for high dose iv amoxicillin
Time interval between development of drug-induced crystalluria and development of AKI for each antibiotic
Measured: up to 14 days after start of treatment for sulfamethoxazole and high dose iv amoxicillin, up to 12 days after start of treatment for ciprofloxacin
Premature dose reduction of antibiotic or premature stopping of antibiotic treatment for each antibiotic
Measured: Up to 14 days of treatment
Evolution of drug-induced crystalluria over time for each antibiotic
The evolution of drug-induced crystalluria (resolution, persistance) will be evaluated in a descriptive manner
Measured: Up to 11 days after start of treatment for sulfamethoxazole and high dose iv amoxicillin and up to 7 days after start of treatment for ciprofloxacin
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted19 Aug 2026
- Study start8 Dec 2025
- Primary completion31 Dec 2026 (estimated)
- Study completion31 Dec 2026 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Drug-induced Crystalline NephropathyStudies of the same condition, open and under way.
- More trials run by Universitair Ziekenhuis BrusselThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Diagnosis
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Enrolment
- 290 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Universitair Ziekenhuis Brussel
- Sponsor type
- University, hospital or other
- Responsible party
- Sponsor
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07772752
- Sponsor's protocol ID
- EC-2025-247
- Acronym
- CRYSTALLINE
- Status last verified
- Aug 2026
- First submitted
- 2 Dec 2025
- Last updated
- 19 Aug 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Yes
Study at a glance
From the registry record, last updated by the sponsor on 19 Aug 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Drug-induced Crystalluria in Sulfamethoxazole, High Dose Ciprofloxacin and High Dose Amoxicillin Treatment: a Prospective Study
- ClinicalTrials.gov ID
- NCT07772752
- Acronym / sponsor ID
- CRYSTALLINE / EC-2025-247
- Conditions
- Drug-induced Crystalline Nephropathy, Drug-induced Crystalluria, Infections Treated With Sulfamethoxazole, High Dose Ciprofloxacin or High Dose iv Amoxicillin
- Keywords
- crystalluria, drug-induced acute kidney injury, drug-induced crystalline nephropathy, amoxicillin, sulfamethoxazole, ciprofloxacin
- Study type
- Interventional
- Recruitment status
- Recruiting
- Enrolment
- 290 participants (estimated)
- Lead sponsor
- Universitair Ziekenhuis BrusselUniversity, hospital or other
- Study start
- 8 Dec 2025 (actual)
- Primary completion
- 31 Dec 2026 (estimated)
- Study completion
- 31 Dec 2026 (estimated)
- First posted
- 19 Aug 2026 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
This study examines in hospitalized patients, treated with sulfamethoxazole, high dose ciprofloxacin or high dose iv amoxicillin, the incidence of drug-induced urinary crystal formation and its association with acute kidney injury development.
Detailed description
This is a prospective study which evaluates in hospitalized patients treated with sulfamethoxazole (po or iv), high dose ciprofloxacin (po or iv) or high dose iv amoxicillin, regardless the indication of the antibiotic treatment, the incidence of development of drug-induced urinary crystal formation. In addition, the association between development of AKI and the development of drug-induced crystalluria will be assessed for each of these antibiotics. Moreover, demographic, clinical and biochemical factors associated with the development of drug-induced crystalluria will be evaluated, as well as the timing of crystalluria development and potential AKI development.
In eligible patients who have provided informed consent first voided morning urine samples will be evaluated for the presence of drug-induced crystals by crystalluria examination at predefined moments, depending on the specific antibiotic treatment (day 2, 4, 6, 8 and 11 after start of antibiotic treatment for amoxicillin treatment, day 3 and 7 after start of antibiotic treatment for ciprofloxacin treatment, day 3, 7 and 11 after start of antibiotic treatment for sulfamethoxazole treatment). Renal function determination by serum creatinine in case of amoxicillin and ciprofloxacin treatment and by serum creatinine and serum urea in case of sulfamethoxazole treatment will be performed at baseline and other predefined moments after the start of antibiotic treatment, depending on the specific antibiotic treatment ( day 1-3, 4-7, 8-11 and 12-14 after the start of antibiotic treatment for amoxicillin treatment, day 3-7 and 8-12 after the start of antibiotic treatment for ciprofloxacin treatment, day 1-4, 5-9, 10-14 after the start of antibiotic treatment for sulfamethoxazole treatment). Occurrence of acute kidney injury will be evaluated. Demographic, clinical and biochemical data will be collected from the electronic medical records, including data on demographics, medical history, medical treatment, data on the antibiotic treatment including dosing and biochemical parameters, including baseline renal function renal function (serum creatinine and eGFR (CKD-EPI), serum urea), CRP. Patients will remain included up to 14 days of antibiotic treatment or until discharge, whatever comes first.
Study design
- Primary purpose
- Diagnosis
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Number of arms
- 1
| Arm | Type | Receives |
|---|---|---|
| Antibiotic treatment | Other | Diagnostic Test: Crystalluria examination |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (17 listed)
- Age ≥ 18 years
- Able to give informed consent without the intervention of a legal representative
- Treatment with
- sulfamethoxazole/trimethoprim, with minimum dose of
- ≥ 800/160 mg q12h oral administration (PO) or intravenous administration (IV) for eGFR ≥ 30 ml/min
Key exclusion criteria (5 listed)
- Unable to give informed consent without the intervention of a legal representative
- No baseline renal function up to 72 hours prior to the start of antibiotic treatment available, evaluated by serum creatinine and eGFR (CKD-EPI)) for all study groups and additional serum urea for the sulfamethoxazole group.
- Treatment duration < 24 hours or insufficiently long to perform one crystalluria inves-tigation as defined in the protocol
- Patients treated with hemodialysis or peritoneal dialysis, anuric patients before start of antibiotic treatment
- Patients with urinary diversions
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Crystalluria examinationCrystalluria examination | Diagnostic test | Antibiotic treatment |
Primary outcome
Incidence of drug-induced crystalluria in patients treated with sulfamethoxazole
Time frame: Up to 11 days after start of treatment
The presence of sulfamethoxazole-induced crystalluria will be evaluated by microscopic crystalluria examination in first voided morning urine samples on day 3, 7 and 11 after start of treatment and will be reported as a dichotomous parameter (present/absent).
Incidence of drug-induced crystalluria in patients treated with high dose ciprofloxacin
Time frame: Up to day 7 after start of treatment
The presence of ciprofloxacin-induced crystalluria will be evaluated by microscopic cyrstalluria examination in first voided morning urine samples on day 3 and 7 after start of treatment and will be reported as a dichotomous parameter (present/absent).
Incidence of drug-induced crystalluria in patients treated with high dose iv amoxicillin
Time frame: Up to 11 days after start of treatment
The presence of amoxicillin-induced crystalluria will be evaluated by microscopic cyrstalluria examination in first voided morning urine samples on day 2, 4, 6, 8 and 11 after start of treatment and will be reported as a dichotomous parameter (present/absent).
Incidence of AKI in patients treated with high dose iv amoxicillin
Time frame: Up to 14 days after start of treatment
Acute kidney injury is defined as an increase in serum creatinine by ≥ 0.3 mg/dl within 48 hours or ≥ 1.5 times baseline within the prior 7 days. The occurrence of acute kidney injury will be performed by calculating the difference between serum creatinine at baseline and during antibiotic treatment at 4 different moments after start of antibiotic treatment, namely day 1-3, day 4-7, day 8-11 and day 12-14.
7 secondary outcomes
Incidence of AKI in patients treated with sulfamethoxazole
Time frame: Up to 14 days after start of treatment
Incidence of AKI in patients treated with high dose ciprofloxacin
Time frame: Up to 12 days after start of treatment
Identification of demographic, clinical and biochemical factors associated with the development of drug-induced crystalluria
Time frame: Up to 11 days after start of treatment for sulfamethoxazole, up to 7 days after start of treatment for ciprofloxacin, up to 11 days after start of treatment for high dose iv amoxicillin
Time interval between start of antibiotic treatment and development of sulfamethoxazole, ciprofloxacin and amoxicillin crystalluria
Time frame: up to 11 days after start of treatment for sulfamethoxazole, up to 7 days after start of treatment for ciprofloxacin, up to 11 days after start of treatment for high dose iv amoxicillin
Time interval between development of drug-induced crystalluria and development of AKI for each antibiotic
Time frame: up to 14 days after start of treatment for sulfamethoxazole and high dose iv amoxicillin, up to 12 days after start of treatment for ciprofloxacin
Premature dose reduction of antibiotic or premature stopping of antibiotic treatment for each antibiotic
Time frame: Up to 14 days of treatment
Evolution of drug-induced crystalluria over time for each antibiotic
Time frame: Up to 11 days after start of treatment for sulfamethoxazole and high dose iv amoxicillin and up to 7 days after start of treatment for ciprofloxacin
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 19 Aug 2026.
- Individual participant dataSharing planned: Yes
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Crystalluria examination in people with Drug-induced Crystalline Nephropathy and Drug-induced Crystalluria, run by Universitair Ziekenhuis Brussel at 1 site in Belgium.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 17 inclusion and 5 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: looking for participants now, as of the sponsor's last update on 19 Aug 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Belgium. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Els Van de Perre, MD (0032 2 477 60 55, els.vandeperre@uzbrussel.be), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Incidence of drug-induced crystalluria in patients treated with sulfamethoxazole (time frame: Up to 11 days after start of treatment). The study lists 4 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 19 Aug 2026.