OVERVIEW

What is neonatal polycythemia?

Neonatal polycythemia refers to a condition where a baby has an excessive number of red blood cells in their bloodstream, leading to a series of symptoms. The main risk factors include increased blood viscosity and slower blood flow due to the elevated red blood cell count, which may result in thrombosis and localized cyanosis. Additionally, the increased destruction of red blood cells can worsen the baby's jaundice.

Polycythemia is defined as a venous hematocrit (Hct) or hemoglobin concentration that is more than two standard deviations above the normal range for the same gestational and postnatal age. Therefore, if a full-term newborn's peripheral venous blood sample shows an Hct greater than 65% or a hemoglobin concentration exceeding 22 g/dL, polycythemia is considered.

Can neonatal polycythemia be cured?

Neonatal polycythemia can be cured. Mild cases without symptoms may only require observation. For severe polycythemia, partial exchange transfusion can be performed to remove excess red blood cells, thereby alleviating symptoms.

Does neonatal polycythemia have long-term complications?

After treatment and recovery, neonatal polycythemia does not cause long-term complications.

Is neonatal polycythemia common?

It is not very common, occurring in approximately 1%–2% of newborns. However, only about 10%–25% of these cases exhibit symptoms. In high-altitude regions, around 5% of newborns may develop polycythemia.

SYMPTOMS

What are the symptoms of polycythemia in newborns?

Most infants with polycythemia show no clinical signs. A visible manifestation is dark red skin all over the body, with possible cyanosis in the lips, hands, and feet. Additionally, they may experience vomiting, refusal to feed, breathlessness, restlessness, and excessive crying. Medical examinations might reveal hypoglycemia, rapid heart rate, and other symptoms. These signs appear at birth, and if the baby is not feeding adequately, the symptoms may worsen within the first 3 days. Newborns with polycythemia also tend to have more severe jaundice.

CAUSES

What are the common causes of neonatal polycythemia?

• The most common cause of polycythemia in full-term infants is delayed cord clamping, such as in home births where the umbilical cord is clamped later at the hospital. This can lead to increased placental transfusion to the newborn, resulting in polycythemia.
• Chronic fetal hypoxia or placental insufficiency in utero. Maternal hypertension, living at high altitudes, or abnormalities in the umbilical cord/placenta can cause fetal hypoxia, stimulating increased red blood cell production.
• Elevated maternal blood sugar, such as in gestational diabetes, can also lead to fetal polycythemia.
• Fetal developmental abnormalities, such as chromosomal disorders like trisomy 21 (Down syndrome), may also present with neonatal polycythemia.

Which infants are most commonly affected by neonatal polycythemia?

• Newborns with a birth weight above the average for their gestational age are more prone to polycythemia.
• Infants of diabetic mothers or those who experienced hypoxia during fetal development are also more likely to develop polycythemia.

When does neonatal polycythemia typically manifest?

Symptoms of neonatal polycythemia may appear at birth. If the infant has poor feeding, symptoms may gradually worsen within the first 3 days.

DIAGNOSIS

What tests are needed for neonatal polycythemia?

Blood tests including complete blood count, blood gas analysis, blood glucose measurement, and biochemical tests are required.

Why are these tests performed for diagnosing neonatal polycythemia?

• Complete blood count (CBC): The primary test for diagnosing polycythemia, focusing on red blood cell count, hematocrit (HCT), and hemoglobin levels. Hematocrit is a key indicator for determining whether partial exchange transfusion is necessary.
• Blood gas analysis: Assesses whether the body shows signs of hypoxia.
• Blood glucose monitoring: Infants with polycythemia are prone to hypoglycemia, requiring glucose monitoring to maintain stable blood sugar levels.
• Biochemical tests: Evaluates liver and kidney function, as infants with polycythemia may develop hyperbilirubinemia, necessitating close monitoring.

What diseases can neonatal polycythemia cause?

Neonatal polycythemia may lead to complications such as neonatal hypoglycemia, neonatal hyperbilirubinemia, neonatal apnea, necrotizing enterocolitis, and thrombosis.

TREATMENT

Which department should be consulted for neonatal polycythemia?

Neonatology, Neonatal Intensive Care Unit (NICU), Hematology.

How is neonatal polycythemia treated?

Comprehensive treatment in the neonatal ward is required. Key points include assessing the degree of polycythemia.

• For asymptomatic infants with polycythemia, management depends on venous hematocrit (hct):
• For asymptomatic infants with peripheral venous hct of 60%-70%, we recommend not performing partial exchange transfusion (PET). Oral intake, weight, and urine output should be monitored to ensure adequate hydration and glucose intake. Venous hct should be rechecked after 12-24 hours while closely monitoring for symptoms.
• For asymptomatic infants with hct >70%, supportive treatment such as IV fluids or PET (less commonly used) may be given.
• For symptomatic infants with polycythemia, we recommend supportive treatment with IV fluids and glucose rather than PET. Additionally, management includes close monitoring of urine output and investigating other potential causes of symptoms. Based on limited data showing short-term benefits, PET is a reasonable treatment option, but current evidence indicates PET does not improve long-term neurodevelopmental outcomes and may carry certain risks (e.g., necrotizing enterocolitis).

What should be noted during hospitalization for neonatal polycythemia?

• In non-accompanied wards, mothers should maintain breast milk production. Regular pumping is advised, and milk can be stored in freezer bags for later use. This ensures the infant has access to breast milk after discharge, which benefits long-term health. Breast milk components promote nerve cell growth, and the act of breastfeeding helps soothe the infant and strengthen the mother-child bond, aiding recovery.
• In accompanied wards, mothers can continue direct breastfeeding while cooperating with medical treatment.

Is follow-up required after discharge for neonatal polycythemia?

Regular infant health checkups after discharge are sufficient, with the first typically at 42 days postpartum to assess development.

Can neonatal polycythemia recur after treatment?

No, it does not recur. Polycythemia is related to the intrauterine environment and does not reappear after birth.

DIET & LIFESTYLE

What should newborns with polycythemia pay attention to in daily life?

• Prioritize breastfeeding. Only use formula as a last resort if breast milk is unavailable.
• After returning home, parents should monitor the baby's skin for jaundice. If yellowing of the entire body, palms, or soles is observed, promptly return to the hospital to check bilirubin levels.
• Ensure adequate feeding to guarantee the baby urinates at least 6 times a day, preventing symptom aggravation due to insufficient feeding.

PREVENTION

Can Neonatal Polycythemia Be Prevented?

• Regular prenatal checkups during pregnancy can help reduce the occurrence of neonatal polycythemia. If conditions like hypertension or hyperglycemia are detected in the mother, timely and effective measures should be taken to control them.
• If polycythemia is detected in a newborn after birth but no symptoms are present, observation may be sufficient. Follow-up blood tests can monitor changes. Ensuring adequate feeding and hydration can mitigate the harmful effects of polycythemia. Additionally, blood glucose and bilirubin levels should be closely monitored, with prompt intervention if abnormalities arise.