Summary![toggle arrow icon](https://manus-media.amboss.com/icons/chevron_up.svg)
Vitamin K deficiency bleeding of the newborn (VKDB) refers to spontaneous bleeding in a newborn caused by a deficiency of vitamin K dependent-coagulation factors. As vitamin K does not cross the placental barrier, is not present in breast milk, and is not synthesized in the sterile gut of a newborn, vitamin K levels are low in all neonates. VKDB is rare in industrialized countries because most children receive a vitamin K injection at birth. VKDB is categorized as early-onset (within 24 hours after birth), classic (within 4 weeks), or late-onset (between 2–8 months). Bleeding is usually intracranial, subgaleal, gastrointestinal, or nasal. Treatment is focused on managing the bleeding with, e.g., transfusions and restoring bleeding homeostasis by administering vitamin K.
Epidemiology![toggle arrow icon](https://manus-media.amboss.com/icons/chevron_up.svg)
- Without prophylaxis: affects 0.25–1.7% of newborns [1]
Epidemiological data refers to the US, unless otherwise specified.
Etiology![toggle arrow icon](https://manus-media.amboss.com/icons/chevron_up.svg)
The underlying cause is always a deficiency of vitamin K, which can be due to various factors:
- Exclusive breastfeeding: low vitamin K levels in breast milk (most important in late-onset VKDB)
- Low liver storage capacity
- Poor placental passage of vitamin K
- Vitamin K deficiency in the mother (e.g., because of anticonvulsant therapy; most important in early-onset VKDB; maternal malnutrition)
- Underdeveloped intestinal flora (which produces vitamin K), e.g., due to premature birth
- Chronic diarrhea of the newborn
- Long-term antibiotic treatment in newborns
- Cholestatic diseases (e.g., biliary atresia)
References:[2]
Classification![toggle arrow icon](https://manus-media.amboss.com/icons/chevron_up.svg)
- Early onset: within 24 hours after birth; intracranial bleeding common
- Classic: : within 1 week after birth; intracranial bleeding rare
- Late onset: between 2–8 months after birth; intracranial bleeding common
Clinical features![toggle arrow icon](https://manus-media.amboss.com/icons/chevron_up.svg)
- Easy bruising
- Bleeding and signs of blood loss (e.g., pale skin)
- Hematuria, hematochezia
Diagnostics![toggle arrow icon](https://manus-media.amboss.com/icons/chevron_up.svg)
- ↑ Prothrombin time (PT)
- Normal or ↑ activated partial thromboplastin time (PTT)
- Normal bleeding time
- ↓ Factors II, VII, IX, and X
Treatment![toggle arrow icon](https://manus-media.amboss.com/icons/chevron_up.svg)
- Transfusions as necessary
- Administration of vitamin K