Disseminated Intravascular Coagulation in Sepsis
A 15-year-old girl is five days after laparotomy for perforated appendicitis and now needs mechanical ventilation. Her abdomen is distended, tense, and tender. After a contrast-enhanced computed tomography she bleeds from her mouth, endotracheal tube, and venepuncture sites. Blood pressure is 90/50 mm Hg, heart rate 121 beats/min, temperature 35.6 °C. Which of the following is the most likely diagnosis?
- A.Undiagnosed haemophilia A
- B.Disseminated intravascular coagulationCorrect
- C.Immune thrombocytopenic purpura
- D.Anaphylactoid reaction to contrast
Explanation
Simultaneous bleeding from mucous membranes, the airway, and every puncture site in a patient with uncontrolled intra-abdominal sepsis is the defining clinical picture of disseminated intravascular coagulation. Severe sepsis is its commonest trigger. Inflammatory cytokines and endotoxin induce tissue factor expression on monocytes and endothelium, which activates coagulation systemically while the natural anticoagulant pathways, antithrombin, protein C, and tissue factor pathway inhibitor, are simultaneously depleted and fibrinolysis is suppressed by plasminogen activator inhibitor 1. Widespread microvascular fibrin deposition follows, contributing to organ dysfunction, while the same process consumes platelets and clotting factors until the patient can no longer form an effective clot anywhere. The result is the paradox of thrombosis and haemorrhage together. Supporting features here are the persisting intra-abdominal source shown by a tense, tender abdomen, respiratory failure requiring ventilation, hypotension, tachycardia, and hypothermia, the last being a marker of decompensated sepsis. Laboratory confirmation shows thrombocytopenia, prolonged prothrombin time, a falling fibrinogen, and markedly raised D-dimer. Treatment is directed at the underlying sepsis with source control and antibiotics, supported by transfusion of platelets, fresh frozen plasma, and cryoprecipitate for active bleeding. The temporal link to the contrast study is coincidental rather than causal.
Why each option
- A.
- Haemophilia is congenital and would have declared itself long before, and it would not present for the first time with this multi-site pattern.
- B.
- Correct. Sepsis-triggered consumption of platelets and clotting factors produces exactly this pattern of simultaneous bleeding from mucosa, airway, and puncture sites.
- C.
- Immune thrombocytopenia causes isolated thrombocytopenia without consumption of clotting factors and is not precipitated by sepsis in this fashion.
- D.
- A contrast reaction causes shock through vasodilation and bronchospasm, typically within minutes, and does not produce a consumptive coagulopathy.
Reference: ISTH Guidance for the Diagnosis and Treatment of Disseminated Intravascular Coagulation, 2018; Surviving Sepsis Campaign Guidelines, 2021
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