Nephrology for the Family Physician - O.I. Bakaliuk 2003

Pediatric Nephrology
Leading Semiotics of Kidney Diseases in Children

It is characterized by the presence of the same syndromes as in adults (dysuria, Renal Colic, HUS, AH, NS, acute or chronic RF) with certain specific features.

Thus, diagnostic difficulties often arise in children with isolated HE, which is detected in 0.31–1% of pediatric patients. Consequently, in a certain number of cases, terms such as "benign Hematuria" or "persistent hematuria" are used, which are believed to be caused by shunting in small renal vessels.

Isolated HE in children is most frequently associated with dysmetabolic nephropathies (hypercalciuria) and hypoplastic dysplasias, whereas isolated PU is typically linked to Fanconi Syndrome or fever. Identifying urinary casts and acanthocytes (G1 Cells, dysmorphic erythrocytes)—which serve as 100% markers of glomerular-origin HE—is of paramount importance for diagnosing the underlying cause of HE in a child. If unmodified erythrocytes are found in the urine in the absence of PU and cylindruria, other family members should be screened to rule out benign familial HE. While this syndrome is a common cause of isolated HE in children, Alport syndrome, "silent" Kidney stones, and other conditions must first be excluded.

In 15% of children with persistent isolated HE lasting over 12 months, the Etiology is most commonly IgA nephropathy, which in 25% of cases follows a progressive course leading to chronic renal failure (R. Shane, 1996). According to the same researcher, other causes of isolated macrohematuria in children include Urinary Tract infections, perineal irritation, urethral stenosis with ulceration, trauma, coagulation disorders, renal calculi, and Wilms Tumor; less frequently, they include pyelocalyceal or urethral diverticula, renal arteriovenous fistulas, and bladder polyps or calculi.

A.I. Piqueras et al. (1998) report the following causes of HE in children: Alport syndrome, IgA nephropathy, thin basement membrane (TBM) nephropathy, normal glomeruli, GN, and vasculitis.

When evaluating Blood pressure, approximate normal values based on age should be taken into account: in infants under one year of age, the normal BP level is 80 + n, where n is the number of months; after one year of age, it is 80 + n, where n is the number of years. The normal minimum BP level is 1/2 of the maximum + 5 mm Hg. A number of hereditary and Congenital Nephropathies and Tubulopathies are accompanied by functional immaturity of the sympathoadrenal system and The Development of hypotonic syndrome.

Nephrotic Syndrome (which in children is classified as congenital or acquired, primary or secondary) may occasionally be of extrarenal origin, such as protein-free edema, hypothyroidism, or Heart Failure.

The course of ACUTE RENAL FAILURE in children—most frequently caused by renal hypoperfusion (35%)—is characterized by the absence of clearly defined stages (such as oliguric or polyuric phases), the development of complications related to electrolyte imbalances, and secondary infections in virtually 100% of cases.

Frequent and sometimes manifesting features of chronic renal failure in children include developmental delay, alkalosis (instead of acidosis), marked osteodystrophy, arterial hypotension, disseminated intravascular coagulation syndrome, and secondary immunodeficiency.

In a significant number of cases, lower urinary tract symptoms in children are caused not by renal pathology, but by functional immaturity or impaired neural Regulation of the structures involved in urination, commonly known as neurogenic bladder.

Another specific semiotic feature of renal diseases in children is abdominal syndrome—the onset of abdominal pain that closely mimics gastrointestinal, hepatic, or helminthic disorders due to the close anatomical relationship between the renal nerve plexus and the celiac and para-aortic plexuses.