How much do you know about renal anemia in children?

It is only for medical professionals to read and refer to the high incidence of CKD anemia in children in China.
It should be detected and prevented as soon as possible, and treated in time
.

At the 26th National Pediatric Academic Conference (NCCPS) of the Chinese Medical Association to be held on October 22-24, 2021, Professor Li Qiu from the Children’s Hospital of Chongqing Medical University brought us a wonderful special report.
The diagnosis and treatment of anemia in children with chronic kidney disease has been explained in detail, come and learn together! Renal anemia is a major cause of anemia in children.
The global prevalence of anemia is high, especially in pregnant women, non-pregnant women and children
.

The WHO survey report shows that children account for about 60% of the total anemia population, the prevalence rate of anemia among preschool children is as high as 47.
4%, and the prevalence rate among school-age children is 25.
4%
.

The global prevalence of chronic kidney disease (CKD) is 9.
1% (including adults and children), and there has not been a downward trend similar to other chronic diseases (Figure 1).
Anemia is a relatively high complication of CKD in children
.

Figure 1 [1] The prevalence of chronic kidney disease Renal anemia is caused by the absolute or relative insufficient production of erythropoietin (EPO) caused by various kidney diseases, especially uremic toxins that affect the production of red blood cells and their lifespan
.

The factors that aggravate anemia are inflammation and secondary hyperparathyroidism
.

Renal anemia can also be combined with anemia caused by nutritional anemia, hemolytic anemia, aplastic anemia and other blood system diseases.
Therefore, when anemia occurs in patients with kidney disease, in addition to renal causes, other reasons should also be considered
.

Anemia can affect the quality of life of patients with kidney disease, increase the risk of kidney disease progression, end-stage kidney disease, cardiovascular events, and death
.

CKD anemia can cause a high incidence of multiple complications in children with CKD, and it will aggravate with the progress of CKD
.

A domestic single-center study involving 171 children with CKD (Figure 2) was divided into CKD stage 3, stage 4, and stage 5 groups according to the estimated glomerular filtration rate.
The results showed that children with stage 3-5 anemia The incidence rates were 27.
3%, 83.
3%, and 95.
4%, respectively, suggesting that with the deterioration of renal function, the incidence of anemia gradually increased, the serum iron level gradually decreased, and the incidence of moderate and severe anemia increased
.

Figure 2 A single-center study of anemia in children with CKD (picture from Professor Li Qiu's PPT) Anemia increases the risk of cardiovascular disease and death in CKD patients
.

Cardiovascular disease is the most important complication of CKD patients and the leading cause of death
.

CKD pays attention to the diagnosis and treatment of anemia in the early stage, which is of great significance for reducing cardiovascular complications and mortality
.

The hospitalization risk of children with CKD anemia is 55% higher than that of non-anemic patients.
Anemia is associated with increased hospitalization frequency and mortality in dialysis children (Figure 3)
.

Figure 3 Hospitalization of children with CKD anemia (picture from Professor Li Qiu's PPT) Early diagnosis of anemia in children with CKD is easily overlooked.
1 Diagnosis of anemia In the diagnosis of anemia, the diagnostic value of children is generally smaller than that of adults (Figure 4).
Adult male hemoglobin (Hb)<130g/L, female Hb<120g/L can be diagnosed as anemia; while children in the development process, the normal range of hemoglobin of different ages is not exactly the same, the smaller the age, the lower the value, so pay attention to different ages when diagnosing The Hb value is different
.

Anemia can be diagnosed when the hemoglobin value of children with CKD is below the 5th percentile of the normal value adjusted for age and gender
.

Figure 4 Anemia diagnosis (picture from Professor Li Qiu's PPT) 2 Evaluation items and evaluation frequency Complete blood count includes Hb value, average red blood cell volume (MCV), average red blood cell Hb content (MCH), average red blood cell Hb concentration (MCHC), white blood cell count And classification, platelet count and reticulocyte count
.

Iron reserve and iron utilization index Serum ferritin can reflect the iron reserve status; total iron binding capacity is the total amount of iron that can be combined with all transferrin in plasma; transferrin saturation reflects the iron that can be used for erythropoiesis, which is serum iron The ratio of binding capacity to total iron; blood vitamin B12, folic acid, erythropoietin (EPO) levels, bone marrow smears and fecal occult blood
.

The medical history is very important for the evaluation of anemia in children with CKD.
The evaluation frequency and items of anemia history at the first diagnosis of CKD are different (Figure 6)
.

Figure 6 Evaluation frequency (picture from Professor Li Qiu's PPT) After the diagnosis of CKD, it is necessary to check whether anemia is complicated.
After anemia is confirmed, a series of examinations should be performed to exclude the possibility of other secondary factors
.

3 The timing of starting treatment is different from that of adults with Hb90-100g/L.
The timing of treatment of anemia in children with CKD is earlier than that of adults, and Hb<110g/L can be started
.

Hb target target It is recommended that the upper limit of Hb target target for the treatment of CKD anemia in children is higher than the adult's 120g/L, preferably 120-130g/L
.

Emphasis on iron supplementation The specific ways of iron supplementation are divided into oral iron and intravenous iron.
Children with non-dialysis and peritoneal dialysis are given priority to oral route, and intravenous iron is recommended for children with hemodialysis
.

In addition, the iron metabolism status should be evaluated.
The specific indicators include iron reserves (serum ferritin) and iron utilization (transferrin saturation).
The frequency of evaluation is recommended every 3 months for non-dialysis and peritoneal dialysis children.
, And children on hemodialysis need dialysis every 1-3 months
.

Erythropoiesis stimulant (ESA) supplements the emphasis on individualized treatment.
The dose should be adjusted according to the specific conditions of the child, such as dialysis mode, degree of anemia, and treatment response.
The initial dose of rHuEPO is 50-100 U/kg per week, divided into two to three times.
It is recommended that children on non-dialysis and peritoneal dialysis be administered subcutaneously, and children on hemodialysis can be administered intravenously
.

After initial treatment or changing the dose, Hb should be measured every 1-2 weeks, and the Hb level should be measured every 4 weeks after reaching the standard
.

And should prompt recognition and prevention of a side reaction may occur, such as hypertension, thrombosis, anaphylactoid reactions, and myalgia, epilepsy and the like
.

It should be noted that ESA can only solve the problem of EPO deficiency, and cannot improve iron absorption and utilization at the same time
.

Roxastat can moderately increase the concentration of erythropoietin, increase the sensitivity of erythropoietin receptors, increase the content and activity of transferrin receptors, and promote the absorption and utilization of iron
.

However, the safety and effectiveness of children's use have not yet been determined, and attention should be paid to observation
.

Blood transfusion therapy is only a symptomatic treatment measure to correct anemia, and the indications for blood transfusion should be strictly controlled
.

There is a high incidence of CKD anemia in children in China, and there are still certain problems in early diagnosis and standardized treatment.
It should be detected and prevented as soon as possible and treated in time
.

During the treatment, pay attention to the target value of Hb and the side effects of the drug, emphasize the principle of individualization, and select the most suitable treatment plan for the child according to the specific situation of the child, such as the dialysis method and the degree of anemia
.

References: [1]Lancet.
2020;395(10225):709-733