Functional disorders of the urinary system in children

Functional disorders of the urinary system organs occur in children with a frequency of 10% in the general population. Among patients of nephrourological hospitals, functional disorders as conditions aggravating the main diagnosis, or as an independent disease, are diagnosed in 50% of children and more.

A healthy child should indicate his desire to empty his bladder already in the second half of life. The natural incentive for this is the unpleasant feeling of wet diapers. The widespread use of diapers, which make child care easier, has led to a delay in the formation of a negative conditioned reflex to wet diapers, a delay in the development of the micturition function.

The criteria for the first stage of maturity, normally achieved by 3-4 years, are as follows:

• compliance of the functional volume of the bladder with the child’s age (on average 100-125 ml);
• adequate number of urinations per day for diuresis and the volume of each urination (no more and no less than 7-9 times);
• complete urinary retention day and night;
• the ability to delay and interrupt the act of urination if necessary;
• the ability to empty the bladder without a previous urge to urinate and with a small volume of urine due to voluntary control of the sphincter mechanism.

If pollakiuria, imperative urges, imperative urinary incontinence, nocturnal enuresis persist in children over 4 years of age, this indicates that the process of formation of the main features of the mature type of urination has not been completed. After the "control age" (4 years), deviations in the nature of urination should be considered a disease.

The second stage lasts from 4 to 12-14 years. There is a gradual increase in the reservoir function of the bladder, a decrease in the tone of the detrusor and intravesical pressure. In puberty (12-14 years), sex hormones are included in the regulation of the main functions of the bladder, potentiating the effects of the sympathetic part of the autonomic nervous system.

The most common cause of delayed maturation and/or disruption of urinary mechanisms in children is the consequences of birth trauma with persistent minimal dysfunction of the brain; fetal hypoxia and conditions associated with the development of hypoxia in the postnatal period (frequent acute respiratory viral infections, pneumonia, sinusitis, nasal breathing disorders).

Depending on the bladder volume at which urination occurs, there are three variants. The bladder is considered normoreflexive if urination occurs at the normal age-related bladder volume, hyporeflexive - at a volume exceeding the upper limit of the norm, hyperreflexive - at a volume below the lower limit of the norm. The causes of changes in the nature of urination can be congenital dysplasia of connective tissue, spinal lesions, neurotic disorders, neurogenic dysfunctions. The most common form of neurogenic dysfunction is a hyperreflexive bladder, it occurs when the conducting nerve pathways of the spinal cord above the sacral segments at the level of the 9th thoracic vertebra are damaged. A rarer variant is a hyporeflexive bladder. There is a weakening of the urge to urinate, rare urination in large portions, a large amount of residual urine. It is observed when the posterior roots of the sacral spinal cord, the equine tail and the pelvic nerve are affected.

In addition to a nephrourologist, a pediatrician, neurologist, and orthopedist take part in the examination of children with neurogenic bladder dysfunction.

[ 1 ], [ 2 ], [ 3 ], [ 4 ], [ 5 ], [ 6 ], [ 7 ], [ 8 ], [ 9 ]