Some Hematological Profile in Children With Chronic Kidney Disease

Chronic kidney disease (CKD) is a major public health issue with an increasing incidence and prevalence worldwide. In CKD, hematological parameters are influenced, it is associated with high morbidity and mortality rates, but there have been very few studies on the hematological profile of children with chronic kidney disease, on follow-up in general, and particularly among chronic kidney disease patients(Melaku.,et al 2022).

CKD is defined by the presence of kidney damage or an estimated glomerular filtration rate (eGFR) less than 60 ml/min/1.73 m2, it can last for 3 months or longer, regardless of the cause. Chronic kidney disease (CKD) is recognized as a major non-communicable disease in children. (Inker.,et al2014).

CKD is classifies it into 6 categories based on glomerular filtration rate (G1 to G5 with G3 split into 3a and 3b). It also includes the staging based on three levels of albuminuria (A1, A2, and A3), with each stage of CKD being sub-categorized according to the urinary albumin-creatinine ratio in (mg/gm) or (mg/mmol) in an early morning "spot" urine sample.( Inker,.et al 2012)

The 6 categories include:

• G1: GFR 90 ml/min per 1.73 m2 and above
• G2: GFR 60 to 89 ml/min per 1.73 m2
• G3a: GFR 45 to 59 ml/min per 1.73 m2
• G3b: GFR 30 to 44 ml/min per 1.73 m2
• G4: GFR 15 to 29 ml/min per 1.73 m2
• G5: GFR less than 15 ml/min per 1.73 m2 or treatment by dialysis The three levels of albuminuria include an albumin-creatinine ratio (ACR)
• A1: ACR less than 30 mg/gm (less than 3.4 mg/mmol)
• A2: ACR 30 to 299 mg/gm (3.4 to 34 mg/mmol)
• A3: ACR greater than 300 mg/gm (greater than 34 mg/mmol). (Inker.,et al2014). hematological parameters such as white blood cell (WBC) include total leukocyte and differential counts, platelet (PLT), and red blood cell (RBC). Parameters, Kidney function ,electrolytes such as Na,k,ca and liver function bleeding time, and pro-thrombin time, are usually affected in CKD . These are common in CKD due to erythropoietin deciency and other factors such as increased hemolysis, suppression of bone marrow erythropoiesis, hematuria, and gastro intestinal blood loss. (George.,et al2015).

All CKD patients, particularly those with an estimated GFR (eGFR) < 60 mL/min/1.73 m2, should be screened for anemia on initial evaluation for CKD. Anemia is defined as Hb < 13 g/dL in men and Hb < 12 g/dL in women, according to WHO criteria. (Hira Shaikh.,et al 2023).

the primary cause of anemia in patients with CKD is insufficient production of erythropoietin by the diseased kidneys. Other factors include iron, folate \& B12 deficiency due to nutritional insufficiency or increased blood loss (Hira Shaikh.,et al 2023). acute and chronic inflammation with impaired iron utilization, sever hyperparathyroidism with consequent bone marrow fibrosis and shortened red cell survival in the uremic environment, bleeding due to dysfunctional platelets, and rarely blood loss from hemodialysis(Hira Shaikh.,et al 2023).

Criteria used to define iron deficiency are different among CKD compared to normal renal function. Among CKD patients, absolut iron deficiency is defined when the transferrin saturation (TSAT) is ≤20% and the serum ferritin concentration is ≤100 ng/mL among predialysis and peritoneal dialysis patients or ≤200 ng/mL among hemodialysis patients. Functional iron deficiency, also known as iron-restricted erythropoiesis, is characterized by TSAT ≤20% and elevated ferritin levels. (TSAT = plasma iron divided by the total iron-binding capacity × 100)( Cappellini .,et al 2017) .

untreated prolonged anemia leads to a number of physiologic disorders, including: cardiovascular complications like decreased tissue oxygenation, increased cardiac output, ventricular dilatation and ventricular hypertrophy and increased mortality and morbidity.( Dwijen Das ., et al 2015).

Iron supplementation is recommended for all CKD patients with anemia. There is general agreement according to guidelines that intravenous (i.v.) iron supplementation is the preferred method for CKD patients on dialysis (CKD stage 5D) and either i.v. or oral iron is recommended for patients with CKD(Tolkien.,et al 2015)