Evaluation of Acute and Chronic Nephrotoxicity in Acute Lymphatic Leukemia Patients Using Ultrasound Localization Microscopy
Phase: NA
Conditions: Acute Lymphoblastic Leukaemias (ALL), Long Term Follow-Up
Sponsor: University of Erlangen-Nürnberg Medical School

Version 1.4; 02.09.2025 - HEALED                                                                                                                        
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Study protocol 
 
 
 
“HEALED” 
Evaluation of acute and chronic nephrotoxicity in acute lymphatic leukemia patients  
using Ultrasound Localization Microscopy 
 
 
 
Trial Short Title 
HEALED 
Trial Full Title 
Evaluation 
of 
acute 
and 
chronic 
nephrotoxicity 
in 
acute 
lymphatic 
leukemia patients  
using 
Ultrasound 
Localization 
Microscopy 
 
Funding 
Internal until application for external 
funds 
Trial Principle Investigator 
Dr. med. A. Dierl 
Dr. med. E-M. Wild 
Dr. med. H. Mandelbaum 
PD Dr. med. A. Karow 
Statistical Analysis Plan Authors 
Dr. med. A. Dierl 
Dr. med. E-M. Wild 
Document Version 
1.4 
Document Version Date 
02.09.2025 
NCT-Number 
Pending 
 
 

Version 1.4; 02.09.2025 - HEALED                                                                                                                        
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Table of conten 
 
TABLE OF CONTENT 
TABLE OF CONTENT 
2 
STUDY TITLE, VERSION NUMBER, VERSION DATE 
3 
ZUSAMMENFASSUNG/PROJECT SUMMARY 
4 
SCIENTIFIC BACKGROUND 
6 
OBJECTIVES 
8 
OUTCOME MEASURES 
9 
STUDY DESIGN 
10 
STUDY POPULATION / IN- AND EXCLUSION CRITERIA 
12 
STUDY PROCEDURES 
14 
RISK-BENEFIT-ANALSYSIS 
16 
DATA MANAGEMENT AND DATA PROTECTION 
18 
STATEMENT ON THE INCLUSION OF MINORS IN ACCORDANCE WITH ARTICLE 20 OF 
THE DECLARATION OF HELSINKI (2024) 
19 
SIGNATURES 
20 
REFERENCES 
21 
 
 
 

Version 1.4; 02.09.2025 - HEALED                                                                                                                        
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3
STUDY TITLE, VERSION NUMBER, VERSION DATE 
 
Study title 
Evaluation of acute and chronic nephrotoxicity in acute lymphatic leukemia patients  
using Ultrasound Localization Microscopy (HEALED) 
 
Version 
1.3 
 
Version date 
06.07.2025 
 
Overview 
Date 
Version 
Status 
Adjustments 
23.04.2025 
1.0 
Draft 
 
23.05.2025 
1.1 
Draft 
Inclusion of funding source 
02.06.2025 
1.2 
Draft 
Adaption of number of participants 
06.07.2025 
1.3 
Draft 
Addition of references to scientific 
background 
02.09.2025 
1.4 
Draft 
Addition of recommendations from the 
Ethics Committee 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

Version 1.4; 02.09.2025 - HEALED                                                                                                                        
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ZUSAMMENFASSUNG/PROJECT SUMMARY 
With increasing survival rates in pediatric oncology, reports of long-term side effects persisting 
decades after treatment are also rising. Clinically evident nephropathies occur in about 5.5% 
of survivors more than five years after therapy. Chemotherapeutic agents such as ifosfamide, 
cisplatin, and carboplatin, as well as kidney-directed treatments like radiation, surgery, or stem 
cell transplantation, increase this risk. Acute kidney injury has also been described in 
association with cyclophosphamide and high-dose methotrexate, which are used in the 
treatment of acute lymphoblastic leukemia (ALL). Studies show a high prevalence of 
albuminuria (around 14.5% of childhood cancer survivors), an early marker of kidney damage, 
while standard parameters like creatinine often become abnormal only at later stages. 
Leukemia survivors suffer from vascular late effects caused by persistent endothelial damage 
triggered by cancer therapies such as anthracyclines, cyclophosphamide, and asparaginase, 
which increase inflammation and thrombosis risk. These vascular changes may also contribute 
to kidney injury. 
ULM is a high-resolution ultrasound technique that uses microbubbles to visualize the 
microvasculature and resolve dynamic blood flow changes with a resolution beyond the 
diffraction limit. ULM is independent of kidney or liver function, has been applied in various 
organs, and was recently used for the first time to visualize glomeruli—the smallest functional 
units of the kidney—in humans. This method enables early detection of glomerular injury as a 
consequence of vascular damage, even before albuminuria appears, potentially allowing 
earlier adaptation of follow-up and initiation of treatment.  
 
This pilot project focuses on survivors of ALL, as they are the largest and best studied pediatric 
cancer patient group also regarding late effects and, therefore, a sufficient number of 
individuals can be expected for his monocentric approach. Vascular functional impairment of 
the kidney could be detected at an early stage and the follow-up structures and measures such 
as the early use of nephroprotective drugs could be adapted. 
 
 

Version 1.4; 02.09.2025 - HEALED                                                                                                                        
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Responsibilities: 
 
Study director: 
Dr. med. Eva-Maria Wild 
Dr. med. Alexander Dierl 
PD Dr. med. Axel Karow 
 
Phone: +49 9131 85 33118, Mail: eva-maria.wild@uk-erlangen.de , alexander.dierl@uk-
erlangen.de, axel.karow@uk-erlangen.de 
Department of Pediatrics and Adolescent Medicine, University Hospital Erlangen, 
Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU) 
Loschgestraße 15, D-91054 Erlangen, Germany 
 
Involved Persons: 
PD Dr. med. Jörg Jüngert, E-Mail: joerg.juengert@uk-erlangen.de 
PD Dr. med. Dr. rer. biol. Hum. Ferdinand Knieling, E-Mail: ferdinand.knieling@uk-
erlangen.de 
PD Dr. med. Adrian Regensburger, E-Mail: adrian.regensburger@uk-erlangen.de 
Dr. med. Henriette Mandelbaum, E-Mail: henriette.mandelbaum@uk-erlangen.de  
 
 
Funding 
Internal funds of the Children's Hospital Erlangen until application for external funds 
 
 

Version 1.4; 02.09.2025 - HEALED                                                                                                                        
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SCIENTIFIC BACKGROUND 
In parallel to increasing survival rates in pediatric oncology, a growing number of studies 
describe an increase in long-term side effects even decades after cancer treatment in 
childhood and adolescence [1].  
 
Long-Term Nephrotoxicity in Childhood and Adolescent Cancer Survivors 
Nephropathies occur in 5.5% of survivors more than 5 years after the end of therapy [2]. 
Chemotherapeutic agents with well documented early nephrotoxicity are ifosfamide, cisplatin, 
and carboplatin. A limited number of studies only evaluated long-term risk and risk factors for 
renal toxicity, and these studies were performed in selected groups of survivors with a 
maximum of 10 years’ follow-up [3]. Other risk factors for nephrotoxicity include kidney 
radiotherapy (including whole body radiotherapy in the setting of stem cell transplantation), 
kidney surgery, or stem cell transplantation [4]. Acute nephrotoxicity has also been described 
with cyclophosphamide and high-dose methotrexate [3, 5, 6], both drugs used in the treatment 
of acute lymphoblastic leukaemia (ALL). There is a general lack of data or studies in other 
groups of cancer survivors.  
 
Few studies describe a high prevalence and risk of reduced kidney function in the form of low 
GFR, albuminuria, or increased blood pressure in long-term survivors of childhood and 
adolescent cancer. For example, Knijnenburg et al. found albuminuria in 14.5% of 1442 
childhood and adolescent cancer survivors analysed (0.7% in the normal population 
comparison group) [3]. Albuminuria is generally considered to be an early and sensitive marker 
in the presence of an often normal GFR [7]. Blood markers, such as creatinine or eGFR, are 
less sensitive because they are generally only detectable at late stages of kidney damage. 
However, given the lack of more sensitive alternatives as early indicators of chronic renal 
toxicity, markers such as creatinine or GFR are often used to monitor kidney function in regular 
(long-term) follow-up after childhood and adolescent cancer. Against this background, the 
establishment of sensitive methods facilitating and early detection of kidney damage appears 
to be of great value.  
 
Endothelial Injury and Long-Term Vascular Toxicity in Leukemia Survivors 
Cancer therapies can lead to a broad spectrum of cardiovascular complications. Among these, 
cardiotoxicities remain of prime concern, but vascular toxicities have emerged as the second 
most common group [8]. Studies have shown that particularly leukemia survivors suffer from 
vascular late effects [9]. Growing evidence suggests that chemotherapeutics affect endothelial 
function, reduce nitric oxide (NO) bioavailability, and lead to endothelial cell activation.  

Version 1.4; 02.09.2025 - HEALED                                                                                                                        
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Resulting endothelial dysfuntion is associated with tissue ischemia, hampered vascular barrier 
function, atherosclerosis, and altered hemodynamics [10]. Cancer therapies can induce and 
exacerbate endothelial injury through direct cytotoxic and cytostatic effects on endothelial cells, 
while also impairing repair mechanisms by reducing endothelial cell proliferation and the 
number of endothelial progenitor cells. Notably, endothelial dysfunction may persist long after 
treatment, as studies in long-term cancer survivors have shown signs of ongoing endothelial 
activation and elevated levels of circulating endothelial cells even decades after therapy.[8] 
Endothelial injury disrupts vascular homeostasis, leading to inflammation, impaired repair 
mechanisms, and a prothrombotic state, thereby contributing directly to the development of 
vascular damage. 
Different drugs are used in the therapy of ALL that cause vascular damage. Anthracyclines 
cause endothelial damage [11], Cyclophosphamide metabolites are believed to cause 
oxidative stress and direct endothelial capillary damage [12], Asparaginase is is an essential 
drug for the treatment of ALL, may increase the risk of thrombosis or bleeding, the incidence 
of symptomatic asparaginase-associated thrombosis ranges from 2–7% in clinical trials [13]. 
 
As vascular late effects such as coronary artery disease caused by endothelial 
impairment are common late effects in childhood cancer survivors, it is reasonable that 
nephropathy in childhood cancer survivors may at least in part also be caused by 
vascular or endothelial effects in addition to a tubular damage [9, 14]. 
 
Visualizing Glomerular Injury: A New Frontier with Ultrasound Localization Microscopy 
Ultrasound Localization Microscopy (ULM) is an advanced and highly sensitive ultrasound 
imaging technique that allows visualisation of the microvasculature and quantification of 
dynamic blood flow changes within the vascular architecture with unprecedented resolution. 
Tiny air bubbles (microbubbles) are administered intravenously as contrast agents, which can 
then be localised and tracked within each image of the ultrasound acquisition [15]. 
Accumulation of all these tracks on a 2D grid produces a microvascular map of the organ with 
a resolution beyond the diffraction limit of ultrasound waves. Unlike other types of contrast 
agents, the microbubbles are subsequently metabolised independently of kidney and liver 
function and will simply be washed out by respiration [16]. ULM has been used in several 
human organs [17-19]. Two studies have already been performed at the Department of 
Pediatrics and Adolescent Medicine (University Hospital Erlangen) using ULM to visualise the 
microvascular architecture in the neonatal brain and to quantify dynamic perfusion changes 
[18, 20]. Moreover, a study with ULM in kidney transplants has been successfully conducted, 
proving the feasibility of the method in patients with renal impairment. More recently, the 
glomerulus, the smallest functional unit of the kidney, has been visualised in the human body 

Version 1.4; 02.09.2025 - HEALED                                                                                                                        
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with high resolution [21]. Glomerular injury is closely linked to vascular damage in the kidneys, 
as endothelial dysfunction and microvascular injury impair glomerular filtration and contribute 
to progressive renal dysfunction. 
The aim of this study is to facilitate the early visualization of glomerular damage representing 
a vascular component of chemotherapy induced nephrotoxicity by ULM. This approach could 
contribute to the timely detection of functional kidney impairment - even earlier than potential 
albuminuria - and thus help to adapt follow-up structures and measures or even revise 
treatment protocols. In the frame of this pilot study, we focus on individuals with a history of 
ALL, as they represent by far the largest and most extensively studied subgroup of patients in 
pediatric oncology. Therefore, we expect a sufficient number of patients in this monocentric 
approach. 
OBJECTIVES 
Hypotheses 
• 
ULM can be used to visualise and quantify the microvascular perfusion dynamics in the 
kidney and differs depending on the organ function  
• 
Treatment of acute lymphoblastic leukaemia leads to (often subclinical) acute and 
chronic impairment of renal function also through vascular injury which can be 
visualized by ULM.  
 
Primary objectives 
• 
ULM: Visualisation of microvascular architecture and Quantification of microvascular 
perfusion dynamics in the kidney before, during, and after treatment of acute 
lymphoblastic leukaemia 
 
Secondary objectives 
• 
ULM: Correlation of the vascular architecture of the kidney visualised by ULM before, 
during and after treatment of acute lymphoblastic leukaemia (e.g. number of 
segmented glomeruli) with laboratory chemical parameters (including renal function 
parameters, inflammation parameters, immunological parameters) 
• 
ULM: Correlation of vascular architecture of the kidney visualised using ULM before, 
during and after treatment of acute lymphoblastic leukaemia (e.g. number of 
segmented glomeruli) with sonographic parameters (e.g. resistance index (RI), flow 
velocity)  
• 
ULM: Correlation of parameters of quantified microvascular perfusion dynamics of the 
kidney before, during and after treatment of acute lymphoblastic leukaemia with 

Version 1.4; 02.09.2025 - HEALED                                                                                                                        
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laboratory chemical parameters (e.g. renal function parameters, inflammation 
parameters) 
• 
ULM: Correlation of parameters of the quantified microvascular perfusion dynamics of 
the kidney before, during and after treatment of acute lymphoblastic leukaemia with 
sonographic parameters (including resistance index (RI), flow velocity) 
 
Study type 
Prospective, monocentric, diagnostic study 
OUTCOME MEASURES  
 All ULM measurements will be performed on the kidney, which is better visualized in 
sonography. 
Primary outcome measures collected by ULM  
ULM: Visualisation of the microvascular architecture of the kidney  
• 
ULM: Quantification of perfusion dynamics in one kidney (including measurement of 
peak enhancement (PE), wash-in area under the curve (WIAUC), wash-in perfusion 
index (WiPI), wash-in rate (WIR), wash-out area under the curve (WoAUC), wash-in 
and wash-out area under the curve (WiWoAUC), wash-out rate (WoR), time to peak 
(TTP), rise time (RT), mean transit time (local) (mTTl) and fall time (FT)). 
 
Secondary targets determined by laboratory chemistry  
• 
Laboratory chemistry parameters (including BB, Diff, Glucose, Na, K, Cl, Ca, LDH, 
Crea, Cystatin C, Uric Acid, CRP, Albumin, Ferritin, Total Protein) 
• 
Urinalysis: including urinary status, proteinuria/haematuria 
 
Secondary outcome measures to be determined sonographically  
• 
Sonographic parameters (including resistance index (RI), Doppler signal, flow velocity, 
and others)  
 
Routine clinical practice measures (not related to the study)  
• 
Collection of clinical data from medical records (these outcome measures are available 
from medical records or will also be collected at initial presentation) 
 
 
 
 

Version 1.4; 02.09.2025 - HEALED                                                                                                                        
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STUDY DESIGN 
Monocentric / multicentric 
This is a monocentric study 
 
Study arms: interventional/control 
Patients fulfilling the inclusion criteria will receive ULM of one kidney. Patients with recently 
diagnosed ALL will receive ULM at two timepoints whereas participants in the oncological 
follow up after treatment for ALL will be examined at a single visit. 
 
Randomization 
Randomization is not planned 
 
Blinding 
Blinding to the study is not possible. Blinding of patients/subjects is not necessary 
 
 
 
 
 

Version 1.4; 02.09.2025 - HEALED                                                                                                                        
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Graphical design of study flow 
                 
Figure 1: Course of Study 
 

Version 1.4; 02.09.2025 - HEALED                                                                                                                        
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STUDY POPULATION / IN- AND EXCLUSION CRITERIA 
Early therapeutic effects 
Late therapeutic effects 
Planned number of patients 
N = 10 ALL 
(recently diagnosed ALL) 
N = 20 ALL 
(completed oncological treatment) 
Planned number of examinations for each participant 
2 (before first CPM according to therapy 
protocol and after completion of 
intensive therapy) 
1 
Inclusion criteria 
- 
Diagnosed acute lymphatic 
leukemia 
- 
Treatment day < 50 according to 
therapy protocol / no 
administration of CPM before first 
examination 
- 
From 3 years to < 18 years 
- 
Diagnosed acute lymphatic 
leukemia  
- 
Completed oncological treatment 
- 
From 3 years to < 18 years 
Exclusion criteria 
- 
Known allergic disposition to 
SonoVue / other contrast agents 
- 
Tattoo in the area of the 
examination field 
- 
Pregnancy 
- 
Breastfeeding mothers 
- 
Contraindication for the use of 
Sonovue 
- 
Critical condition 
- 
Known clinically evident renal 
impairment 
- 
Known allergic disposition to 
SonoVue / other contrast agents 
- 
Tattoo in the area of the 
examination field 
- 
Pregnancy 
- 
Breastfeeding mothers 
- 
Contraindication for the use of 
Sonovue 
- 
Critical condition 
 
 
 
Number of patients 
As this is a pilot study, it is not possible to calculate the exact number of patients. It is 
planned to include 30 patients (in total 40 examinations). The planned sample size of 30 
participants (10 during therapy and 20 in follow-up) was determined based on the annual 
incidence of ALL at our center, which is approximately 15 cases per year. Recruitment within 
the intended timeframe of 12–18 months is therefore considered feasible. In addition, the 
study has a pilot character, aiming to provide the first data set for estimating effect sizes and 
to serve as a foundation for the design of larger subsequent studies. 10 patients who will 
undergo an ULM examination of the kidney before the start of chemotherapy, latest before 
therapy day 50 before the first application of high-dose methotrexate or cyclophosphamide 
(Timepoint 1). After completion of intensive therapy (after administration of 
cyclophosphamide and high-dose methotrexate), they will receive a follow-up ULM 

Version 1.4; 02.09.2025 - HEALED                                                                                                                        
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examination (Timepoint 2) approx. 6-9 months after the first ULM examination. In addition, 20 
different patients who have completed treatment for ALL and are seen during aftercare will be 
included in the study. 
 
 
Recruitment 
Patients (and parents) will be informed about the possibility to participate in the study when 
visiting the pediatric clinic for hematology and oncology (including its outpatient clinics) or 
attending the follow-up consultation (Department for internal Medicine / Med 5 University 
Hospital Erlangen). If patients and their parents are interested to participate, they will be fully 
informed about the aims and methods (especially about the scientific/explorative nature of the 
study), the benefits and risks, and the revocability of participation in the study before giving 
their consent prior to study initiation. Patients in childhood and adolescence are additionally 
informed and educated about the study and its procedure in an age-appropriate manner. 
 
  
 
 

Version 1.4; 02.09.2025 - HEALED                                                                                                                        
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STUDY PROCEDURES 
Procedure for informing and obtaining consent 
Patients or subjects can only be enrolled in the study after written informed consent has been 
obtained. The written informed consent requires an oral and written explanation to the 
patients/subjects, as well as their parents or legal guardians, about the aims and methods 
(incl. scientific-explorative character of the study), benefits and risks as well as the 
revocability of the study participation. Children and adolescents are informed by means of 
age-appropriate, comprehensible patient information sheets. By giving written informed 
consent, the patients/participants as well as their parents/guardians declare that they agree 
with the collection and storage of study-relevant data and their review by monitoring or 
authorities. It must be clearly conveyed to the study participant that withdrawal of consent is 
possible at any time and without any disadvantage. Furthermore, all study 
participants/subjects and parents/guardians are informed that this study is a purely scientific 
study without any current diagnostic or therapeutic benefit. In case of incidental findings, the 
study participants/test persons and parents/guardians will be informed and further 
clarification will be initiated if indicated.  
The original consent form will be kept in the study folder at the study site. The patient/proband 
and parent/guardian will be given a copy of the patient information and consent form. The 
patient information and informed consent form can be found in the appendix of this study 
protocol. 
 
Measures and recording the target values 
Together with the patient and the patient's family, a date for the study is set. After the patient 
has been informed about the study by phone or in person at least one day in advance, a routine 
blood sample is taken through a venous access during the chemotherapy or follow-up visit. 
Patients currently undergoing treatment will already have a venous access used for 
chemotherapy (CVC or Hickman catheter or port catheter). This can then be used for the study-
related contrast  agent, so no additional intervention is required. The region to be examined in 
all patients is one kidney and its immediate surroundings. Patients can lie relaxed during the 
scan. 
 
Timing and duration of the study  
Patients will be examined using ULM during an outpatient or inpatient stay for chemotherapy 
or aftercare. A total of 30 patients will be included in the study.  
The expected duration of the study for individual patients is 30 minutes to 1 hour. 
 

Version 1.4; 02.09.2025 - HEALED                                                                                                                        
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Total duration of the study  
The expected total duration of the study is 18 months. 
 
 
 

Version 1.4; 02.09.2025 - HEALED                                                                                                                        
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RISK-BENEFIT-ANALSYSIS 
Study-related risks with ULM  
Insertion of a peripheral venous catheter (pVK)  
For the examination using ULM in the 20 individuals who have completed treatment for ALL 
and are seen during aftercare it is necessary to insert a peripheral venous catheter (pVK) (e.g. 
in the hand, crook of the elbow). The insertion of a peripheral venous catheter is generally 
feasible without limitations even in children after completion of chemotherapy. For this study, 
catheter placement will be combined with routine blood sampling to avoid additional burden. 
As with any blood sampling, this can result in injury to the skin at the entry point. There is also 
a risk of infection at the entry site, but this is very low given the short time of insertion of approx. 
2 hours.  
In the 10 individuals who will be assessed before therapy day 50 (Visit 1) and after completion 
of intensive chemotherapy (Visit 2), the routinely implanted central venous catheter will be 
used for the administration of the contrast agent. In these cases, no additional pVK is required. 
Laboratory chemistry parameters (including BB, Diff, Glucose, Na, K, Cl, Ca, LDH, Crea, 
Cystatin C, Uric Acid, CRP, Albumin, Ferritin, Total Protein) and urinalysis including urinary 
status, proteinuria/haematuria as well as conventional ultrasound assessment are routinely 
performed during therapy and aftercare. So, in addition to ULM, no extra procedure will be 
undertaken in the frame of this study. 
Contrast agent application 
A contrast medium (SonoVue®) is administered venously, a potential intolerance to the 
contrast medium (allergic reaction) is a possible however very low risk of this study. It is an 
already established contrast agent the tolerability of which has been investigated in several 
studies: In a large study , 23,188 patients examined showed a rate of 0.0086% ‘adverse events’ 
(18). In a separate investigation, 30,222 patients were examined, with a rate of 0.02% (19). 
The adverse events included self-limiting symptoms such as redness, epistaxis, vomiting, 
nausea, back pain, numbness and symptoms of incipient anaphylaxis (18, 19).  
In our working group, children have already been examined several times using ULM and 
SonoVue contrast enhancement.  
The information for healthcare professionals on SonoVue reports very rare cases of reactions 
with fatal outcome that were temporally related to the use of SonoVue®. Notably, the patients 
concerned were already at high risk of cardiac complications.  
Repeated applications during an examination are permitted, overdoses have not been 
described. SonoVue® has no drug approval for this examination or intravenous use in children 
and will be used off-label. SonoVue® is not nephrotoxic, remains intravascular, and is 

Version 1.4; 02.09.2025 - HEALED                                                                                                                        
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17
eliminated via the lungs and phospholipid metabolism. It can be safely administered even in 
patients with impaired renal function. 
The ULM measurements are performed using a CE certified clinical ultrasound system. 
 
Study related benefits  
The data obtained in this study may provide important insights into the acute and chronic 
nephrotoxicity of ALL therapy. The potentially quantifiable differences in ULM could be used in 
the future as markers to predict nephropathy. Follow-up methods and measures, schedules 
and treatment plans could be adapted. 
 
Withdrawal criteria  
Withdrawal criteria are an allergic reaction to the ultrasound contrast agent and reddening or 
warming of the skin during optoacoustic imaging.  
The entire study will be stopped if a reassessment of the expected and unexpected side effects 
of the drugs or devices used indicates an increased risk to the subjects. 
Statement on medical justifiability  
Based on experience to date, the risk of adverse events is considered to be extremely low.  
With ULM, the rate of side effects is very low and if they do occur, they are rapidly reversible 
and easily treatable.  
Given the current lack of diagnostic tools and data on post-chemotherapy nephrotoxicity, we 
assume this method will provide new diagnostic tools that will significantly improve long-term 
follow up care in the future.  
 
Calculation of case numbers 
As this is a pilot study and no information is yet available on the expected differences between 
the different groups, no calculation of the number of cases has been made. The number of 
cases given is an estimate. 
 
Statistics 
The data is given as a mean value with standard deviation. Correlations are indicated with the 
non-parametric Spearman correlation coefficient (Rs). Differences in the mean values are 
analysed statically using a non-parametric T-test (Mann-Whitney test) or ANOVA. In all 
analyses, an error level of <0.05 is considered statically significant. 
 
 
 
 

Version 1.4; 02.09.2025 - HEALED                                                                                                                        
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DATA MANAGEMENT AND DATA PROTECTION 
Data collection and data storage 
The participation of the individual subjects in the study is documented and the principal 
investigator keeps a separate list to identify the participating subjects. This list contains the 
name and date of birth as well as the study date and pseudonymisation code of the subjects. 
The principal investigator is responsible for the quality of data collection and data storage. The 
data is stored exclusively on computers or specially designated network drives at the University 
Hospital Erlangen.  
 
Pseudonymisation 
Prior to a scientific analysis of the data from this study, all information is pseudonymised in 
accordance with the guidelines of the Federal Data Protection Act. 
 
Revocation, data deletion 
If consent is withdrawn, data collected up to this point may be considered and retained. 
However, test persons have the right to demand that the data be destroyed, provided that there 
are no legal provisions to the contrary. 
 
Participant insurance 
All participants in the study are insured via the CCS Erlangen group contract. This will be 
pointed out separately in the patient information. 
 
 

Version 1.4; 02.09.2025 - HEALED                                                                                                                        
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19
STATEMENT ON THE INCLUSION OF MINORS IN ACCORDANCE WITH ARTICLE 20 OF 
THE DECLARATION OF HELSINKI (2024) 
The inclusion of children and adolescents (aged 3–<18 years) is indispensable, as the 
research question specifically and exclusively pertains to this patient population. Data derived 
from adults cannot be extrapolated, given the substantial differences in disease characteristics, 
treatment protocols, and late effects. 
 
Scientific Rationale 
Ultrasound Localization Microscopy (ULM) allows for the early and non-invasive detection of 
glomerular damage. This approach provides novel opportunities for preventive measures and 
for the adaptation of long-term follow-up care in survivors of acute lymphoblastic leukemia 
(ALL). 
 
Risk–Benefit Assessment 
ULM is a non-invasive procedure and will be performed via pre-existing central venous access 
or, in the follow-up setting, in combination with routine blood sampling where applicable. 
The contrast agent (SonoVue®) has an excellent safety profile and is associated with only a 
very low risk of adverse reactions. 
The examination itself is of short duration (approximately 30–60 minutes). 
Accordingly, the associated risks are minimal and clearly outweighed by the anticipated 
scientific and clinical benefit. 
 
Information and Consent 
Parents or legal guardians will receive comprehensive information and provide written 
informed consent prior to participation. 
Children and adolescents will be informed in an age-appropriate manner and their assent will 
be sought. 
Withdrawal from participation will be possible at any time without any disadvantages. 
 
Conclusion 
The inclusion of minors is scientifically necessary and ethically justifiable. It will be conducted 
with the utmost consideration for their specific need for protection and in strict adherence to 
ethical and regulatory standards. 
 
 
 

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SIGNATURES 
 
 
Dr. med. E. Wild 
 
 
 
 
Dr. med. A. Dierl 
 
 
 
 
PD Dr. med. Axel Karow 
 
 
 
 
Dr. med. H. Mandelbaum 
 
 
 
 
 

Version 1.4; 02.09.2025 - HEALED                                                                                                                        
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REFERENCES 
1. 
Oeffinger, K.C., et al., Chronic health conditions in adult survivors of childhood cancer. N 
Engl J 1. 
Oeffinger, K.C., et al., Chronic health conditions in adult survivors of 
childhood cancer. N Engl J Med, 2006. 355(15): p. 1572-82. 
2. 
Gebauer, J., et al., Multidisciplinary Late Effects Clinics for Childhood Cancer Survivors in 
Germany - a Two-Center Study. Oncol Res Treat, 2018. 41(7-8): p. 430-436. 
3. 
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