Cystitis in children

Causes and mechanisms of development

In childhood, inflammation of the urinary bladder almost never occurs primarily—the disease is secondary in nature. Urodynamic disorders act as the key factor. These can be anatomical (e.g., urethral stricture in girls or the presence of posterior urethral valves in boys) and functional (various neurogenic dysfunctions, in particular, detrusor-sphincter dyssynergia). Any obstruction to urine outflow leads to chronic intravesical hypertension, creating a favorable background for microbial inflammation to join.

Puberty in girls deserves special mention. Under the influence of estrogens, the vaginal microflora reorganizes, increasing the risk of local inflammatory processes of the genital organs, after which the infection enters the urinary tract via the ascending route (especially against the background of reduced immunity).

The pathogen can also enter the bladder per continuitatem—that is, by contact from adjacent inflamed organs. In addition, non-infectious (aseptic) causes exist. These include dysmetabolic nephropathies (mucosal damage by oxalate, urate, or phosphate crystals) and iatrogenic impacts such as radiation therapy or the administration of certain medications (cytostatics, sulfonamides).

Cystoscopic picture

The degree of bladder wall involvement varies: from small superficial foci to total involvement of all layers. During cystoscopy, specialists distinguish the following forms of inflammation:

• Catarrhal: only edema and hyperemia of the mucosa are visualized.
• Granular: against the background of pronounced hyperemia, small granules up to three millimeters in diameter appear.
• Bullous: the edema is so severe that the mucosa acquires a characteristic "cobblestone pavement" appearance.
• Fibrinous: specific fibrinous deposits are found on the bladder walls.

Symptoms of acute cystitis

By the nature of its course, the disease is divided into acute and chronic. Classic acute cystitis is characterized by a clinical triad:

1. Pain syndrome. Pain is localized in the lower abdomen (suprapubic area) and often radiates to the perineum.
2. Dysuric syndrome. Includes frequent urination (pollakiuria) and severe pain during micturition. Imperative, i.e., urgent, urges appear. Urinary incontinence ("wet pants" symptom) is characteristic, and enuresis occurs in some cases.
3. Hemorrhagic syndrome. It is quite rare and manifests as terminal macrohematuria—the passage of blood at the very end of urination.

Paradoxical ischuria—involuntary urine leakage against the background of a severely overfilled bladder—acts as a specific symptom. It is important to note that intoxication syndrome is not characteristic of cystitis. The child's well-being is not impaired, and body temperature remains within normal limits or rises only to subfebrile values. An exacerbation of a chronic process proceeds similarly to acute cystitis.

Features in infants and young children

Due to their age, young children are unable to verbalize their complaints. Therefore, in infant and toddler patients, so-called dysuria equivalents come to the forefront of the clinical picture.

Cystitis can be suspected by behavior: the child begins to cry, scream, and exhibit marked motor agitation before, during, or immediately after micturition. Due to severe pain spasm of the external sphincter and pelvic floor muscles, reflex urinary retention often develops. Parents may also notice episodes of incontinence.

Laboratory diagnostics and treatment

The laboratory picture in urinary bladder inflammation has clear criteria. Urinalysis reveals moderate leukocyturia and hematuria of varying severity (with erythrocytes remaining unaltered). In the complete blood count, a systemic inflammatory response is absent—parameters remain within normal limits, which is particularly typical for older children.

The main goal of antibacterial therapy is to create the maximum bactericidal concentration of the drug directly in the urinary bladder cavity. Medications are prescribed exclusively orally (per os). Drugs of choice include:

• Fosfomycin: approved for use in children over 5 years of age, prescribed as a single dose.
• Nitrofuran derivatives: prescribed for a 5–7 day course. Furazidine (5 mg/kg/day) or nitrofurantoin (5–7 mg/kg/day) is used.
• Co-trimoxazole (a combination of sulfamethoxazole and trimethoprim).

Class and exam questions

What else to study on this topic

• Mechanisms of detrusor-sphincter dyssynergia formation
• Differential diagnosis of crystalluria types (oxalate, urate, phosphate)
• The role of anatomical anomalies (posterior urethral valves in boys) in the pathogenesis of intravesical hypertension
• Mechanism of action of iatrogenic triggers: the effect of radiation therapy and cytostatics on the bladder mucosa

Other topics in "Chapter 8. Kidney and Urinary Tract Diseases"

Prepared by WhiteCoat Pro faculty in accordance with the medical school curriculum. For educational purposes only.