Pathogenesis of the neurogenic bladder

The pathogenesis of the neurogenic bladder is complex and not fully understood. Leading role belongs to hypothalamic-pituitary insufficiency, delay in the maturation of the centers of the system of regulation of the act of urination, dysfunction of the autonomic nervous system (segmental and supra-segmental levels), receptor sensitivity and detergent bioenergetics. In addition, there is a certain adverse effect of estrogen on urodynamics of the urinary tract. In particular, hyperreflexia in girls with an unstable bladder is accompanied by an increase in estrogen saturation, which causes an increase in the sensitivity of M-holinoretseptorov to acetylcholine. This explains the predominance of girls among patients with micturition disorders of a functional nature.

Among the pathological factors involved in the formation of a neurogenic bladder, we can distinguish the following:

• insufficiency of supraspinal inhibition of spinal centers of regulation of urination of a dysontogenetic character;
• asynchronous development of the regulation of the act of urination;
• dysfunction of the autonomic nervous system (segmental and supra-segmental apparatus);
• dysfunction of neuroendocrine regulation;
• receptor sensitivity disorders;
• violations of bioenergetics detrusora.

Recently, the idea that in childhood the neurogenic bladder is most often associated not with the anatomical lesion of the spinal reflex arches but with the violation of the neurohumoral regulation of the bladder due to the immaturity of the microcancer centers has recently been established. Neurogenic bladder can be temporary and often prone to spontaneous disappearance by 12-14 years. However, during this time, the neurogenic bladder in many children leads to the development of infectious and inflammatory diseases of the urinary system, which tend to recurrent and are more difficult to treat.

In the obstetrical anamnesis, in almost 80.6% of the children, data are available for transgenic intrauterine hypoxia, birth trauma, or asphyxia in labor and 12.9% for trauma in the cervical spine. Probably, the neurogenic bladder in most cases can be considered as one of the remote manifestations of perinatal encephalopathy.

Depending on the volume of the bladder, at which urination occurs, the following variants of the neurogenic bladder stand out. The urinary bladder is considered normoreflectory if urination occurs with a normal volume of the bladder, hyporeflective - at a volume exceeding the upper limit, and hyperreflective - the lower limit of the norm.

Depending on the adaptation of the detrusor to the volume of urine, an adapted and unadapted (unblocked) bladder is isolated. Detrusor adaptation is considered normal with a slight uniform increase in intravesical pressure in the accumulation phase and disturbed when detrusors react with spontaneous contractions during the bladder filling period, causing sudden jumps of intravesical pressure of more than 16 cm. In this case, there are imperative urges. The presence of a neurogenic bladder in some cases is related to the position of the child's body. There is a special variant, which is manifested only in the vertical position (postural neurogenic bladder). The simplest way to determine the violations of the reservoir and adaptive capacity of the bladder is to fix the rhythm of spontaneous urination during the day with normal drinking regimen.

Thus, in the classification of neurogenic dysfunction of the bladder, there are:

• hyperreflective (adapted, unadapted);
• normoreflectory (unadapted);
• hyperrefectorial postural (adapted, unadapted);
• normoreflectory postural (unadapted);
• hyporeflective (adapted, unadapted);
• hyporeflectory postural bladder (adapted)

[1], [2], [3], [4], [5], [6]