Disseminated Intravascular Coagulation (DIC) in Children
Introduction to Disseminated Intravascular Coagulation (DIC) in Children
Disseminated Intravascular Coagulation (DIC) is a complex and potentially life-threatening condition characterized by the systemic activation of coagulation pathways. In children, DIC presents unique challenges due to their developing hemostatic systems and varied etiologies. DIC results in the formation of widespread blood clots in small blood vessels throughout the body, leading to organ dysfunction and simultaneously depleting clotting factors and platelets, which can cause severe bleeding.
Key points:
- DIC is not a primary disease but a secondary process resulting from an underlying condition
- It can occur in both acute and chronic forms
- The pediatric population is particularly vulnerable due to their immature coagulation systems
- Early recognition and prompt management are crucial for improving outcomes
Pathophysiology of DIC in Children
The pathophysiology of DIC in children involves a complex interplay of coagulation activation, fibrinolysis, and inflammatory processes:
- Initiation: Tissue factor exposure triggers the extrinsic coagulation pathway
- Thrombin generation: Excessive thrombin production leads to widespread fibrin deposition
- Consumption of clotting factors: Ongoing coagulation depletes clotting factors and platelets
- Fibrinolysis activation: Initially increased to counteract clot formation, but may become impaired
- Microvascular thrombosis: Leads to organ ischemia and dysfunction
- Bleeding: Results from consumption of clotting factors and platelets
In children, the immature hemostatic system can lead to a more rapid progression and severe manifestations of DIC compared to adults. The balance between pro-coagulant and anti-coagulant factors is particularly delicate in neonates and young infants, making them more susceptible to DIC in various clinical scenarios.
Etiology of DIC in Children
DIC in children can be triggered by various underlying conditions:
- Infections:
- Sepsis (bacterial, viral, fungal)
- Meningococcemia
- Severe viral infections (e.g., dengue hemorrhagic fever)
- Trauma:
- Severe tissue injury
- Burns
- Head trauma
- Malignancies:
- Acute leukemias
- Solid tumors
- Obstetric complications:
- Placental abruption
- Amniotic fluid embolism
- Vascular disorders:
- Kasabach-Merritt syndrome
- Large vascular malformations
- Severe hepatic failure
- Toxic reactions:
- Snake bites
- Drug reactions
- Massive transfusions
In neonates, additional causes include:
- Perinatal asphyxia
- Respiratory distress syndrome
- Necrotizing enterocolitis
Clinical Presentation of DIC in Children
The clinical manifestations of DIC in children can vary widely depending on the underlying cause, the child's age, and the stage of DIC. Common presentations include:
- Bleeding:
- Petechiae and purpura
- Mucosal bleeding (e.g., gums, nose)
- Gastrointestinal hemorrhage
- Excessive bleeding from venipuncture sites
- Thrombosis:
- Acral cyanosis
- Organ dysfunction due to microvascular thrombosis
- Skin necrosis
- Signs of underlying condition:
- Fever, tachycardia, and hypotension in sepsis
- Specific signs related to the primary disease
In neonates, additional signs may include:
- Respiratory distress
- Poor feeding
- Lethargy
- Seizures
It's important to note that the clinical presentation can range from subtle abnormalities in laboratory values to fulminant multi-organ failure. A high index of suspicion is necessary, especially in high-risk patients.
Diagnosis of DIC in Children
Diagnosing DIC in children requires a combination of clinical assessment and laboratory investigations:
Laboratory Tests:
- Complete Blood Count (CBC):
- Thrombocytopenia
- Schistocytes on peripheral blood smear
- Coagulation Studies:
- Prolonged Prothrombin Time (PT)
- Prolonged Activated Partial Thromboplastin Time (aPTT)
- Decreased fibrinogen levels
- D-dimer: Elevated levels indicate active fibrinolysis
- Fibrin Degradation Products (FDPs): Elevated
- Antithrombin III levels: Often decreased
Diagnostic Criteria:
The International Society on Thrombosis and Haemostasis (ISTH) DIC score can be used, but it's important to note that it's not specifically validated for children:
| Test | Result | Score |
|---|---|---|
| Platelet count | >100 x 10^9/L 50-100 x 10^9/L <50 x 10^9/L |
0 1 2 |
| D-dimer | No increase Moderate increase Strong increase |
0 2 3 |
| Fibrinogen | >1 g/L <1 g/L |
0 1 |
| Prolonged PT | <3 seconds 3-6 seconds >6 seconds |
0 1 2 |
A score ≥5 is compatible with overt DIC. Scores should be calculated daily to monitor progression.
It's crucial to consider age-specific normal values when interpreting laboratory results in children, especially in neonates and infants.
Management of DIC in Children
The management of DIC in children focuses on treating the underlying condition and supporting the coagulation system:
1. Treat the Underlying Cause:
- Antibiotics for sepsis
- Surgical intervention for trauma or obstetric complications
- Specific treatments for malignancies or other primary conditions
2. Supportive Care:
- Maintain adequate tissue perfusion and oxygenation
- Correct electrolyte imbalances and metabolic abnormalities
- Provide appropriate fluid resuscitation
3. Blood Product Replacement:
- Platelets: Transfuse if <50,000/μL or active bleeding
- Fresh Frozen Plasma (FFP): To replace coagulation factors
- Cryoprecipitate: If fibrinogen <100 mg/dL
- Packed Red Blood Cells: For significant anemia or ongoing blood loss
4. Anticoagulation:
In cases of predominant thrombosis:
- Heparin: Low-dose unfractionated heparin (10-15 units/kg/hr) may be considered
- Antithrombin concentrate: May be beneficial, especially in sepsis-induced DIC
5. Other Therapies:
- Recombinant activated Factor VII: May be used in life-threatening bleeding unresponsive to other measures
- Tranexamic acid: In cases of hyperfibrinolysis
Close monitoring of clinical status and laboratory parameters is essential to guide therapy and assess response. The balance between pro-coagulant and anticoagulant therapies is delicate and should be tailored to each patient's specific needs.
Prognosis of DIC in Children
The prognosis of DIC in children varies widely and depends on several factors:
- Underlying cause: The nature and severity of the primary condition significantly impact outcomes
- Timing of diagnosis and intervention: Early recognition and prompt treatment improve prognosis
- Severity of organ dysfunction: Multi-organ failure is associated with poorer outcomes
- Age of the child: Neonates may have more severe courses due to their immature coagulation systems
Mortality rates in pediatric DIC can range from 10% to 50%, depending on the underlying cause and severity. Sepsis-induced DIC tends to have higher mortality rates compared to trauma-induced DIC.
Long-term Complications:
- Chronic organ dysfunction due to microvascular thrombosis
- Neurological sequelae in cases of CNS involvement
- Venous thromboembolism
- Post-thrombotic syndrome
Follow-up care and monitoring are essential, even after the acute phase of DIC has resolved. This includes assessing for potential long-term complications and addressing any persistent coagulation abnormalities.
Disseminated Intravascular Coagulation (DIC) in Children
- What is Disseminated Intravascular Coagulation (DIC)?
DIC is a serious condition characterized by widespread activation of the coagulation system, leading to both thrombosis and bleeding. - Which of the following is NOT a common cause of DIC in children?
Chronic liver disease (Common causes include sepsis, severe trauma, and malignancies) - What is the primary mechanism underlying DIC?
Excessive activation of the coagulation cascade leading to consumption of clotting factors and platelets - Which laboratory finding is typically seen in DIC?
Prolonged prothrombin time (PT) and activated partial thromboplastin time (aPTT) - What is the significance of elevated D-dimer levels in DIC?
It indicates increased fibrin degradation and is a marker of ongoing coagulation and fibrinolysis - Which organ system is most commonly affected in pediatric DIC?
The hematological system, manifesting as bleeding and/or thrombosis - What is the role of antithrombin III in DIC?
Antithrombin III levels are often decreased in DIC due to consumption and impaired synthesis - How does sepsis-induced DIC differ from trauma-induced DIC in children?
Sepsis-induced DIC often has a more gradual onset compared to the acute presentation in trauma-induced DIC - What is the primary goal of DIC treatment in children?
To treat the underlying cause while supporting the coagulation system and managing complications - Which blood product is most appropriate for correcting coagulopathy in DIC?
Fresh frozen plasma (FFP) as it contains all coagulation factors - What is the role of heparin in treating pediatric DIC?
Heparin may be used in specific cases of DIC with predominant thrombotic manifestations, but its use is controversial - How does DIC affect platelet count in children?
DIC typically causes thrombocytopenia due to increased platelet consumption - What is the significance of schistocytes on a peripheral blood smear in DIC?
Schistocytes indicate microangiopathic hemolytic anemia, which can occur in severe DIC - Which coagulation factor is often the first to be depleted in DIC?
Fibrinogen is often the first factor to be significantly depleted - What is the role of vitamin K in managing DIC?
Vitamin K administration is generally not beneficial in DIC as the coagulopathy is not due to vitamin K deficiency - How does DIC affect fibrinolysis?
DIC initially activates fibrinolysis, but prolonged DIC can lead to fibrinolysis shutdown - What is the significance of prolonged aPTT with normal PT in a child with suspected DIC?
This pattern is atypical for DIC and may suggest an alternative diagnosis such as hemophilia - Which organ is most susceptible to microvascular thrombosis in pediatric DIC?
The kidneys are particularly susceptible to microvascular thrombosis in DIC - What is the role of recombinant activated factor VII (rFVIIa) in managing pediatric DIC?
rFVIIa use in pediatric DIC is controversial and generally reserved for life-threatening bleeding unresponsive to conventional therapy - How does DIC affect the synthesis of coagulation factors?
DIC can impair hepatic synthesis of coagulation factors due to microvascular thrombosis and organ dysfunction - What is the significance of elevated liver enzymes in a child with DIC?
Elevated liver enzymes may indicate hepatic involvement and dysfunction, which can worsen coagulopathy - How does DIC in neonates differ from DIC in older children?
Neonatal DIC often has a more fulminant course and may be associated with specific triggers like necrotizing enterocolitis - What is the role of antifibrinolytic agents in managing pediatric DIC?
Antifibrinolytic agents are generally contraindicated in DIC as they may exacerbate thrombosis - How does DIC affect the function of natural anticoagulants like protein C and protein S?
DIC leads to consumption and functional deficiency of natural anticoagulants, exacerbating the prothrombotic state - What is the significance of a rapidly dropping fibrinogen level in a child with DIC?
A rapidly dropping fibrinogen level indicates severe, ongoing consumption and is associated with poor prognosis - How does DIC affect wound healing in children?
DIC can impair wound healing due to microvascular thrombosis and coagulation factor deficiency - What is the role of thromboelastography (TEG) in managing pediatric DIC?
TEG can provide real-time assessment of coagulation dynamics and guide targeted blood product replacement - How does DIC affect the risk of intracranial hemorrhage in children?
DIC increases the risk of intracranial hemorrhage due to coagulopathy and potential microvascular thrombosis - What is the significance of persistent thrombocytopenia after initial management of DIC in children?
Persistent thrombocytopenia may indicate ongoing DIC, development of complications, or an alternative diagnosis - How does obesity affect the risk and course of DIC in children?
Obesity may increase the risk and severity of DIC due to chronic inflammation and altered coagulation profiles
