Common Disorders in Paediatric Nephrology: Diagnosis, Prevention, and Management

Abstract

Paediatric nephrology is frequently seen as a challenging aspect of paediatric care and necessitating specialised expertise. Nevertheless, the typical issues encountered in paediatric nephrology, such as urinary tract infections and mild micturition disorders, often do not require the attention of a paediatric nephrologist and can be managed effectively by a general practitioner. Urinary tract infections frequently present to emergency centres. They commonly include acute pyelonephritis and uncomplicated cystitis, differentiated upon clinical presentation. Urinalysis, urine culture, acute phase reactants, and renal and bladder ultrasound are the mainstay for the diagnosis. Except for asymptomatic bacteriuria, antibiotic treatment is necessary in the management. Micturition disorders are more common in nephrological outpatient clinics and encompass a wide range of urinary issues, with primary nocturnal enuresis and various forms of daytime micturition problems being the most prevalent. These disorders can be classified as primary or secondary, as well as monosymptomatic or non-monosymptomatic. The diagnosis is based on history and voiding diary and supplemented with imaging and functional diagnostic procedures, as needed. The management primarily involves urotherapy, complemented with medications, if necessary.

1. Introduction

Paediatric nephrology encompasses a wide range of conditions necessitating specific treatment. From this perspective, the more prevalent conditions in this domain, such as urinary infections and micturition disorders, differ, as their basic treatment does not typically require the specialised expertise of a paediatric nephrologist but can be managed by a general paediatrician or primary care paediatrician. Therefore, this chapter aims to provide support and further education to all paediatric experts encountering these conditions due to their frequency, seeking additional validation or supplementation of the management without specialised knowledge in paediatric nephrology.

Urinary tract infections (UTI) and micturition disorders are prevalent childhood conditions frequently encountered in clinical settings. UTI are often observed in the emergency department, especially in febrile children with sudden onset symptoms, potentially indicating a severe infection. Prompt diagnosis and treatment are imperative to differentiate UTI from other bacterial infections and mitigate the risk of long-term complications, notably renal scarring.

Conversely, micturition disorders represent a common yet non-life-threatening nephrological conditions in paediatrics. These disorders typically manifest in outpatient settings and significantly affect a child’s daily life and functionality, exerting a notable impact on their psychological well-being. Both UTI and micturition disorders are significant due to their frequency and their potential long-term implications for quality of life.

2. Urinary tract infections

UTI are among the most common bacterial infections in paediatrics [1] and are the most common serious bacterial illness in febrile children up to 2 years of age in the emergency setting [2]. The demographic characteristics appear to play a crucial role in epidemiological examinations of UTI. The greatest occurrence of febrile UTI is observed among boys under 3 months of age who are uncircumcised, followed by girls below 1 year of age [2]. However, due to the heterogeneous studies differing in age range, inclusion criteria, race, circumcision status, and location of enrolment, epidemiological data is inconclusive. Nevertheless, estimates suggest that by the age of seven, approximately 8% of girls and 2% of boys will experience at least one episode of UTI [3]. Up to 30% of patients experience recurrence of the infection during the first year after initial UTI [4]. Recurring UTI are suggestive for underlying kidney disorder, most commonly congenital anomalies of the kidney and urinary tract (CAKUT) [4].

The pathology is usually divided into febrile upper UTI (most commonly acute pyelonephritis) and lower UTI (most commonly cystitis) [1]. They differ in clinical presentation and management, as presented in Table 1. The infection may spread ascendingly, which is more common, and haematogenously, which is more frequently found in neonatal period. In this case, UTI may manifest as sepsis with nonspecific clinical features (mainly feeding problems, irritability, convulsions, pallor, hypothermia, and sometimes jaundice) [4]. Otherwise, acute pyelonephritis commonly manifests with a high temperature, abdominal or flank pain, sometimes accompanied by malaise, vomiting, or diarrhoea, and should be considered in every child with a fever of unknown aetiology [5]. Symptoms and signs indicative of lower urinary tract involvement comprise suprapubic or abdominal discomfort accompanied by tenderness, painful urination (dysuria), frequent urges to urinate, urgency, cloudy or foul-smelling urine, and recent onset of daytime wetting or bedwetting (nocturnal enuresis) [6].

Characteristic	Acute pyelonephritis	Uncomplicated cystitis	Asymptomatic bacteriuria
Age distribution	More common in younger children	Typically in children aged >2 years	Across all age groups
Fever	>38°C	Afebrile or low-grade fever ≤38°C	Absent
Systemic symptoms	Common	Uncommon	Absent
Local symptoms	Flank pain and/or tenderness	Dysuria, urgency, frequency, urinary incontinence, suprapubic pain, or haematuria	Absent
Causative agent	Bacterial (E. coli is the commonest)	Bacterial (E. coli is the commonest), viral, fungal, and chemical	Bacterial
Gross haematuria	Uncommon	May have fresh blood and clots	Absent
Urine culture for bacteria	Positive	Positive (bacterial cause) or negative (non-bacterial cause)	Positive
Renal and bladder ultrasound	Normal or may reveal edema and hyperaemia of kidney	Normal or may reveal thickened urinary bladder wall, debris in the bladder	Unremarkable
Renal complications	Renal scarring	None	None
Antibiotic treatment	7–10 (14) days	3–5 days	None

Table 1.

Features distinguishing between acute pyelonephritis, uncomplicated cystitis, and asymptomatic bacteriuria.

Most commonly encountered bacteria, causing UTI, is Escherichia coli, responsible for 80–90% of cases, followed by Proteus mirabilis, Klebsiella spp., and Staphylococcus saprophyticus [4]. The presence of bacteria in the urine at specified quantitative counts (colony forming units, CFU) without having signs and symptoms is characteristic of asymptomatic bacteriuria, present in <1% of children [7]. Clinically, we differ it from UTI as presented in Table 1. Along with urine contamination, asymptomatic bacteriuria is a common confounding entity during the evaluation of a symptomatic child that was determined to not have a UTI. As a rule, it is not recommended to screen for or treat asymptomatic bacteriuria in children [8].

2.1 Diagnosis

Accurate and reliable diagnosis of UTI in children is very important, due to immediate or long-term harm, namely renal scarring, with underdiagnosis and unnecessary treatment and potentially invasive diagnostic procedures with overdiagnosis. Basic diagnostics consists of urinalysis and urine culture [9].

Firstly, an appropriate urine sample must be obtained, usually clean midstream catch, if possible. The use of bag specimens is strongly discouraged due to their notably high rate of false positivity. If required in younger children, catheterisation or, rarely, suprapubic aspiration provides additional possibilities of urine sampling. With these two methods, the culture threshold (CFU/ml) might be lower [9].

Urinalysis has proven to be a crucial supplement to urine culture when identifying UTI. Evaluating inflammation through pyuria can assist in distinguishing between contamination/colonisation or asymptomatic bacteriuria, from infection [9]. While evidence indicates that pyuria can manifest without UTI, such as during fevers from other infections or conditions like Kawasaki disease or following intense physical activity, it is uncommon for it to be absent in genuine UTI cases [10]. Furthermore, urinalysis includes a urinary nitrite test, which, if positive, strongly suggests bacteriuria. However, the absence of nitrites does not rule out urinary tract infection [9, 10].

Along with pathologic urinalysis, urine culture should be positive with the presence of a single uropathogen in specified quantitative counts, demonstrated as CFU/ml [11]. The majority of paediatric laboratories adhere to thresholds ranging from 10⁴ to 10⁵ CFU/ml for clean catch/midstream urine samples and catheter urine samples [9]. Defining infections based on culture poses challenges due to asymptomatic bacteriuria or a contaminant, which can yield growth levels resembling infection. In a true UTI, the same pathogen might be detected also in blood cultures, especially in younger patients with haematogenous spread of infection [12].

Supplementary diagnostic tests of upper UTI, namely acute pyelonephritis, include acute phase reactants determination, such as C-reactive protein, white blood cell count, and erythrocyte sedimentation rate, which, when elevated, can help in the diagnosis of upper UTI, differentiating it from lower UTI and asymptomatic bacteriuria. It is important to mention that stand-alone are not neither completely sensitive nor specific for detecting UTI and its localisation and therefore should be used along with history and clinical examination [13].

Imaging diagnostic techniques, typically renal and bladder ultrasound, commonly aid in location determination, as well as potential abscess visualisation or renal/bladder malformation, suggestive for CAKUT, most commonly vesicoureteral reflux (VUR). In children with febrile UTI, renal and bladder ultrasonography should be performed as soon as possible [14]. If there are abnormalities, or UTI are recurring, voiding cystourethrogram is indicated, as well as some additional diagnostics if necessary [14, 15]. Also, in children with positive family history of CAKUT and an UTI, voiding cystourethrogram might be considered, since a large number of CAKUT are genetic in origin [16]. Otherwise, upper UTI is characterised with ultrasound as enlarged kidneys with hypoechoic parenchyma and loss of the normal corticomedullary junction [17]; meanwhile, in the later stages of cystitis, thick bladder wall with irregular surface is seen, and sometimes urine may contain fine suspended echoes [18].

2.2 Prevention

The mainstay of prevention, especially in children with increased risk for infection, such as VUR and other CAKUT, has historically been low-dose antibiotic prophylaxis [19]. Prolonged antibiotic therapy might decrease the likelihood of recurrent symptomatic UTI in children with a history of one or more prior UTI. However, the potential advantage needs to be weighed against the heightened risk of microbial resistance, which must be carefully considered [19]. Even more, recent systematic review showed that low-dose continuous antibiotic prophylaxis plays some limited role in preventing recurrences, mainly in children with significant obstructive uropathies until surgical correction, and was not recommended in children with a previous UTI, recurrent UTI, VUR of any grade, isolated hydronephrosis, and neurogenic bladder [20].

Consequently, other interventions for prevention of UTI in children are being researched, most commonly probiotics, D-mannose, vitamin A, cranberry, nasturtium, horseradish, and others, but yielded insufficient evidence on their effect versus antibiotics [21, 22, 23]. Other preventive measures include satisfactory liquid consumption, intermittent catheterisation in patients with incomplete bladder emptying, and bladder bowel dysfunction management [14].

In children with UTI and some potential functional voiding problems, non-pharmacological preventive approaches of voiding and defecation have to be implemented.

2.3 Management

The management of UTI depends on its presentation and localisation.

Asymptomatic bacteriuria is characterised by the absence of an inflammatory reaction, occurring at all ages and usually resolves spontaneously in a few months to a couple of years [24]. In otherwise healthy children, treatment is not recommended because it promotes antimicrobial resistance and other adverse effects [24].

Acute pyelonephritis and cystitis require antimicrobial treatment. The decision between oral and parenteral treatment should hinge upon factors including patient age, clinical suspicion of urosepsis, aversion to fluids, food, and oral medication, as well as the presence of vomiting, diarrhoea, and complicated pyelonephritis. In neonates and infants under 2 months old, it is advisable to opt for parenteral antibiotic therapy due to the heightened risk of urosepsis and severe pyelonephritis. These cases may also involve electrolyte imbalances leading to potentially life-threatening hyponatraemia and hyperkalaemia associated with pseudohypoaldosteronism. Clinicians should remain vigilant for anatomical abnormalities, such as obstructive conditions, which may contribute to these complications [25, 26].

Prompt and efficient treatment of UTI can reduce the likelihood of infection spreading and resulting in renal scarring. Research indicates that shorter antibiotic regimens (lasting 1–3 days) yield less favourable outcomes when compared to longer courses lasting 7–14 days [10, 27]. Nevertheless, uncomplicated cystitis may be managed effectively with antibiotic regimens lasting 3–5 days [28]. For young infants, it might be worthwhile to contemplate a brief period of parenteral treatment followed by an early transition to oral antibiotics. In cases where outpatient treatment is preferred, it is imperative to ensure active monitoring, medical oversight, and readiness to modify therapy if needed [25].

The selection of an antimicrobial for empirical therapy should be performed by the local prevalence of resistant uropathogens. However, particularly in young febrile children at high risk of renal involvement, it is prudent to opt for an antimicrobial with a low resistance profile among organisms. Presently, the majority of uropathogens demonstrate susceptibility to third-generation cephalosporins. For afebrile children, it would be more appropriate to consider first-generation cephalosporins, trimethoprim-sulfamethoxazole, or nitrofurantoin. Notably, the use of amoxicillin is discouraged due to widespread resistance among uropathogens [24].

Management also involves addressing complications associated with UTI, which parallel those seen in any febrile illness in young children. These complications may include dehydration, electrolyte imbalances, and febrile seizures. Although renal complications stemming from acute pyelonephritis are uncommon in otherwise healthy children, they may involve the development of a renal abscess or the complete blockage of a pre-existing partial ureteropelvic junction. Acute kidney injury might arise due to dehydration or the administration of nonsteroidal anti-inflammatory drugs like ibuprofen, which can also lead to diminished renal function by inducing papillary necrosis or interstitial nephritis. Additionally, interstitial nephritis may be caused by the antibiotic used to treat UTI. Urosepsis is a potential complication, particularly in cases of Gram-negative infections [24]. As UTI can be associated with a CAKUT or micturition problems, additional diagnostics has to be performed as appropriate [1].

The most significant long-term complication of acute pyelonephritis is renal scarring, with reported prevalence approximately around 15% [29]. This prevalence ranges from 3% after the first UTI to 29% after more than three febrile UTI [24]. Although renal scarring may not show clinical symptoms in the majority of children, it can result in hypertension, proteinuria, and a gradual deterioration in renal function, particularly in instances of significant bilateral scarring [30]. Delayed onset of antibiotic therapy is linked to a heightened risk of scarring, with children whose treatment begins within 24 hours of fever onset having a 74% lower likelihood of developing new renal scarring compared to those whose treatment is initiated after 72 hours of fever onset [31].

3. Micturition disorders

Urinary issues in children, known as micturition disorders, encompass a range of problems including nocturnal enuresis, incontinence, urgency, nocturia, pollakisuria, hesitancy, straining, weak or intermittent stream, dysuria, and retention. These disorders can be classified as primary or secondary, as well as monosymptomatic or non-monosymptomatic [32, 33].

The cause of micturition disorders in children is complex and not fully understood. Several studies have attempted to identify early risk factors in children experiencing nighttime or daytime incontinence, but their findings have often been unclear or even contradictory. Research indicates that children with micturition disorders and low birthweight tend to have a lower estimated bladder capacity compared to children of the same age. Low birthweight is also linked to other perinatal factors like low gestational age (which is directly linked to low birthweight) and APGAR score, both of which may impact further development, including micturition [34]. Additionally, age, gender, and the mother’s level of education are significant risk factors for enuresis, with the prevalence of primary nocturnal enuresis being notably higher in children with a positive family history of enuresis, particularly when present in the fathers’ history [35].

The most prevalent urinary issue seen in children is primary nocturnal enuresis, characterised by bedwetting in a child over the age of 5, with at least one incident per month persisting for a minimum of three consecutive months. In its primary form, this condition denotes a child who has not consistently stayed dry at night since infancy. Secondary primary nocturnal enuresis occurs when bedwetting resumes after a period of at least 6 months of dryness. Additionally, monosymptomatic nocturnal enuresis is characterised by bedwetting without accompanying symptoms of daytime urinary issues, whereas the presence of such symptoms leads to the classification of non-monosymptomatic nocturnal enuresis [33].

The high occurrence rate of primary nocturnal enuresis indicates its common presence, with approximately 16% of five-year-olds estimated to experience bedwetting. Even at the age of 7, close to 10% continue to exhibit frequent bedwetting (more than three nights per week) [36, 37]. Additionally, another study demonstrated the prevalence of bedwetting less than two nights per week in 30% of 4.5-year-olds and 8% of 9.5-year-olds, and the prevalence of bedwetting more than two nights per week in 8% of 4.5-year-olds and 1.5% of 9.5-year-old children [38]. However, the prevalence of bedwetting diminishes, as children grow older. Additionally, bedwetting is more prevalent among boys [36, 37]. Conversely, daytime urinary incontinence during childhood is frequently underestimated and receives less effective treatment. According to one study, it was identified in 15.5% of children aged 4.5 and in 4.9% of those aged 9.5 [39]. In another population-based study, daily urinary incontinence occurrences within the last 6 months were reported in 16.9% of children [40].

Incontinence can manifest in two main ways: less frequently as continuous incontinence, suggesting an underlying anatomical or neurological condition, or intermittent incontinence, which is more common. These forms can be further categorised as primary or secondary, as well as monosymptomatic or non-monosymptomatic [33]. Daytime incontinence can be accompanied by several other micturition disorders, which can also be present as stand-alone. Urgency refers to the sudden and unexpected experience of an immediate and compelling need to void. Nocturia is the complaint that the child has to wake at night to void. Hesitancy refers to the challenge in starting urination when the child feels the urge to urinate. Straining involves the child reporting the need to exert significant effort to raise intra-abdominal pressure in order to start and sustain urination. Dysuria is the complaint of burning or discomfort during micturition. Voiding stream can also be weak or intermittent. Intermittency implies micturition that is not continuous but rather has several discrete stop-and-start spurts. Urinary retention describes the feeling of being unable to urinate despite continuous attempts, even with a fully distended bladder. Pollakisuria is defined by increased frequency of urination with small urine volume [33]. Normal voiding frequency ranges between 3 to 8 times per day with voiding ≥8 times per day defining increased daytime urinary frequency and voiding ≤3 times per day decreased daytime urinary frequency.

A number of micturition disorders, summarised in Table 2, manifest with daily urinary incontinence and other symptoms [33].

Micturition disorder	Definition	Clinical manifestations
Overactive bladder	Overactivity of detrusor, seen in cystometry	Urgency, frequent voiding, nocturia, incontinence, and absence of UTI
Underactive bladder	Underactivity of detrusor, seen in cystometry (not always present with the same clinical manifestations)	Straining is needed to start, continue, and end voiding, increased bladder volume, and urine residual volume
Holding manoeuvres	Habitual retention of urine	Decreased frequency of voiding, urgency, and overflow incontinence
Dysfunctional micturition (the term is used for neurologically healthy children)	Habitual contractions of the urethral sphincter and pelvic floor muscles	Intermittent stream
Bladder outlet obstruction	Urinary flow obstruction during urination (mechanical/functional)	Weak stream
Stress incontinence	Urinary incontinence with small amounts of urine during physical exertion or other activity which increases intra-abdominal pressure	Urinary incontinence with coughing, sneezing, etc.
Vaginal reflux	It is caused by urinating with adducted legs, in which the urine is trapped in the vaginal introitus; it can result from labia adhesions due to local inflammation	Daily incontinence in moderate amounts immediately after urination
Laughter incontinence	Urinary incontinence during or immediately after laughing
Extreme daytime frequency	Frequent need to urinate during the day	Pollakisuria, urinating at least once per hour and small urine volumes
Bladder neck dysfunction	Difficult or too slow opening of the bladder neck, despite normal or increased detrusor contractions	Weak stream
Bladder and bowel dysfunction	The simultaneous presence of bladder and bowel disorder (constipation, encopresis)

Table 2.

Frequent daytime micturition disorders.

3.1 Diagnosis

The identification of micturition disorders relies on reviewing medical history and conducting clinical assessments. Through the patient’s medical background, we can differentiate between monosymptomatic and non-monosymptomatic disorders and pinpoint the primary micturition issue. It is crucial to consider potential systemic conditions like renal or neurological diseases, as well as diabetes mellitus, which may influence the onset of micturition disorders [36].

During assessment of a child with a micturition disorder, a completed questionnaire and voiding diary are required, where the patient records their fluid intake, micturition frequency, timing and quantity of urination episodes, micturition patterns, and defecation frequency. By analysing this recorded data, we can assess the child’s bladder capacity and compare it with the anticipated capacity for his/her age. For ages 4–12, this expected capacity is calculated using the equation: 30 × (age in years + 1), up to a maximum of 390 ml. A reduced bladder capacity is indicated if the estimated maximum urine per micturition is less than 65% of the expected bladder capacity for the child’s age. Nocturnal polyuria is identified if the volume of urine produced at night exceeds 130% of the expected bladder capacity for the child’s age [33, 36].

During the clinical assessment, specific findings are typically absent, yet we remain vigilant for potential indicators such as an abdominal mass (indicating an enlarged bladder or constipation), anatomical variations in the genital region, and external manifestations associated with neurogenic bladder dysfunction [36].

For each child, a basic urine analysis is conducted. Glycosuria may suggest diabetes, while proteinuria could indicate chronic kidney disease. Attention is also given to the possible presence of pyuria and the urine’s specific gravity. Furthermore, a routine ultrasound examination of the urinary tract is often conducted to evaluate post-void residual urine volume. An elevated residual volume is noted when urinary retention surpasses 30 ml or 21% of bladder capacity in children aged 4–6 years or exceeds 20 ml or 15% of bladder capacity in children aged 7–12 years. Ultrasound is also employed to evaluate constipation. Further invasive tests are determined based on the patient’s symptoms, although they should not be conducted in cases of monosymptomatic nocturnal enuresis [37, 41].

In cases of micturition disorders, urine flow recording or uroflowmetry alongside urodynamic tests are commonly employed. Uroflowmetry is utilised to measure micturition duration, urine volume, and to delineate the shape of the urine curve [33]. It is imperative that the volume of urine is adequate, as indicated by the curve at a volume exceeding 50% of the calculated urinary bladder capacity. To enhance reliability, multiple measurements are consistently conducted. A typical curve exhibits a bell shape. However, a columnar or sudden, high-amplitude curve of brief duration suggests an overactive bladder. Conversely, a staccato curve, irregular yet continuous, implies a dissonance between the bladder and the sphincter. An intermittent curve manifests as flow with numerous peaks and complete halts, indicative of an underactive bladder or dysfunctional micturition. Additionally, a plateau-shaped curve, characterised by a flattened, low-amplitude, and prolonged pattern, signals a blockage in the outflow tract from the urinary bladder [33].

The urodynamic assessment involves evaluating both the filling and emptying phases of the urinary bladder. Using cystometry during the filling phase, we assess the sensory function of the bladder, detrusor function, bladder compliance, and bladder capacity. In the emptying phase, cystometry examines the relationship between pressure and volume during urination, detrusor function during urination, and urethral function during urination. This examination is conducted when there is suspicion of a neuropathic bladder, as well as in cases of obstruction, dilated ureters, bladder neck dysfunction, lack of response to treatment, history of neurological conditions, and anatomical abnormalities [33].

3.2 Prevention

Preventive measures for micturition disorders are often limited due to the various factors that influence a child’s development. Primary enuresis is primarily attributed to pathophysiological factors such as an altered diuretic hormone profile, arousal failure, and delayed bladder maturation, with significant influence from genetic factors. Nevertheless, somatic and psychosocial environmental factors play a significant modulatory role. Addressing potential coexisting conditions like constipation and obesity may prove beneficial in preventing the onset of enuresis [42, 43]. Good bladder control necessitates appropriate toilet training at a suitable age [44]. Particular attention should be directed towards children with preexisting conditions, predisposing them to an elevated risk of micturition disorders, such as anatomical abnormalities and nervous system diseases. Regular assessment of voiding patterns and prompt intervention if necessary are crucial in their care.

3.3 Management

The primary treatment approach is urotherapy, characterised as non-surgical and non-pharmacological interventions aimed at addressing lower urinary tract disorders in children and adolescents. Urotherapy, a specialised practice, has emerged as the cornerstone therapy, not only for daytime urinary incontinence but also for addressing issues such as nocturnal enuresis, functional constipation, and faecal incontinence [45].

Urotherapy encompasses both standard and specific approaches. Standard urotherapy involves educating children and parents about micturition disorders, dispelling myths surrounding them, and providing guidance on behavioural modifications. These modifications may include ensuring adequate fluid intake during the day while restricting it in the evening for those experiencing nocturnal enuresis, encouraging regular urination intervals and pre-bedtime voiding, discouraging restraining manoeuvers, promoting optimal urination posture, advocating for a balanced diet and regular bowel movements, maintaining a diary, and attending regular check-ups. Support and encouragement have to be offered throughout this process [45, 46].

Tailored measures are implemented to address the individual’s specific incontinence disorder. For instance, if there are associated issues with defecation, the primary focus will be on treating those problems before addressing urinary concerns [45, 46].

Specific urotherapy encompasses a range of treatment modalities tailored to the individual’s needs. These may include:

1. Biofeedback: utilising a feedback loop method to help individuals gain control over their urinary function by providing real-time information about physiological processes. This form of treatment is primarily indicated for dysfunctional micturition. The method not only focuses on training relaxation of the pelvic floor muscles but also educates individuals about the activity of the abdominal muscles. Additionally, it involves visualising the electromyographic activity of the pelvic floor muscles. This visualisation can be combined with real-time urine flow measurement display or interactive computer games, enhancing engagement and effectiveness of the treatment process [47].

2. Neuromodulation: employing techniques to modulate nerve activity and alter bladder function, often through electrical stimulation. This treatment can be administered through various methods, including transcutaneous, intravesical, endoanal, and anogenital ones. Techniques may involve stimulating the posterior tibial nerve or implanting a sacral nerve pulse generator. The electric current is believed to directly affect the central nervous system, facilitating the reactivation of pelvic floor muscles, modulating bladder function, and improving control of the external urethral sphincter and pelvic floor. It also aims to establish balance and coordination of sacral reflexes. However, research findings do not consistently demonstrate immediate effectiveness of this treatment [48, 49].

3. Intermittent catheterisation: a procedure involving periodic insertion of a catheter into the bladder to empty urine, particularly useful in cases of urinary retention or incomplete bladder emptying.

4. Cognitive-behavioural therapy: addressing psychological factors influencing urinary function through therapeutic techniques aimed at modifying behaviour and thought patterns, including increasing motivation for treatment and adherence to urotherapy, alleviating stress and feelings of guilt associated with incontinence through counselling [46].

5. Psychotherapy: in-depth therapy sessions aimed at exploring and addressing psychological issues contributing to urinary problems. Urinary incontinence is frequently associated with attention deficit hyperactivity disorder and personality disorders [50].

6. Specific group programs: offering specialised group interventions tailored to children with unresponsive urinary disorders, providing support, education, and targeted interventions within a group setting.

7. Bedwetting alarm: the night waking alarm system activates when a sensor positioned in the underwear detects urine leakage. Upon activation, a loud sound signal prompts the child to wake up. The child is then expected to turn off the alarm, fully empty the bladder in the toilet, change clothes, and reinstall the sensor. This mechanism operates on the principle of a conditioned reflex. The ultimate objective is to develop an awareness of bladder fullness, suppress its immediate emptying, and consequently enhance the ability to retain urine during the night. Effective treatment is greatly influenced by the motivation and cooperation of the child and the entire family [37].

These specific urotherapy approaches aim to address the unique needs of individuals with urinary disorders, employing a multidisciplinary approach to optimise treatment outcomes.

Urotherapy can be complemented and combined with pharmacological and surgical interventions, if needed.

Desmopressin is commonly prescribed in cases of persistent primary nocturnal enuresis that are unresponsive to urotherapy. It is an analog of antidiuretic hormone with extended action, functioning by promoting increased water reabsorption, resulting in urine with higher concentration and reduced volume. It is typically administered to the child in the evening, approximately 1 hour before bedtime. It is important for the child to refrain from drinking fluids for 1 hour before taking the medication and for 8 hours afterward. Desmopressin exclusively operates during the night it is administered, necessitating daily intake. Concurrently, adherence to standard urotherapy guidelines regarding fluid intake and urination is essential for optimal outcomes [37].

Pharmacological therapy is also indicated for daily micturition disorders with overactive bladder and bladder outlet obstruction. In the first case, muscarinic receptor blockers (oxybutynin, tolterodine, solifenacin, and propiverine) can be considered, and in the second case, alpha-adrenergic receptor blockers. In the treatment of overactive bladder, oxybutynin is most often used, but the others listed are also effective, however, are not yet approved for use in all countries. Adverse effects of treatment with muscarinic receptor blockers include dry mouth, facial flushing, tachycardia, difficulty concentrating, constipation, and visual disturbances [46]. Alpha-adrenergic receptor blockers also have limited approval, although their effectiveness has been proven. By blocking the alpha-adrenergic receptors in the area of the urinary bladder, they lower the outflow resistance from the bladder and improve its emptying. Adverse effects (hypotension, fatigue, and muscle weakness) are less pronounced when taking the drug in the morning [51, 52].

Surgical interventions for micturition disorders are infrequent in paediatric cases but may be considered for patients with genitourinary tract anomalies [53]. One potential option is the use of botulinum toxin, which can be applied in children with neurogenic bladder and in cases of non-neurogenic micturition disorders that do not respond to standard treatments [54].

4. Conclusions

UTI and micturition disorders are frequently encountered in paediatric nephrology. Both conditions can have long-term implications for a child’s health. Achieving an accurate diagnosis can be challenging due to various factors that must be taken into consideration. Therefore, comprehensive management including prevention is essential, although preventive measures may be limited. A comprehensive approach is crucial for achieving optimal outcomes.

Conflict of interest

The authors declare no conflict of interest.