Vitamin K deficiency and coagulopathy of liver disease

01OverviewDefinition, clinical context and the essential points that orientate the chapter.

Vitamin K is needed to gamma-carboxylate factors II, VII, IX and X and anticoagulant proteins C and S. Deficiency follows inadequate intake combined with illness, fat malabsorption or cholestasis, prolonged antibiotics, pancreatic or biliary disease, or a vitamin K antagonist. The PT becomes prolonged early because factor VII turns over quickly. APTT rises in severe depletion. Platelet count and fibrinogen remain normal unless another process coexists. A response to phytomenadione supports deficiency, but urgent bleeding requires simultaneous treatment rather than a delayed therapeutic trial.

Liver disease is different. Hepatic synthesis of procoagulants falls, but so do protein C, protein S and antithrombin. Factor VIII and VWF are maintained or increased, ADAMTS13 falls, platelets may be low from portal sequestration and thrombopoietin deficiency, and fibrinolysis varies. This creates a vulnerable rebalance that can tip toward bleeding or thrombosis with infection, renal failure, endothelial injury or intervention. INR was standardised for warfarin monitoring and cannot represent this whole system.

When bleeding occurs, identify the source. Portal pressure and variceal rupture are treated with resuscitation, vasoactive therapy, antibiotics and urgent endoscopy; plasma correction alone does not control them and its volume can worsen portal pressure. Trauma or surgery needs anatomical haemostasis. Low fibrinogen during active bleeding may justify cryoprecipitate or fibrinogen concentrate; platelets are guided by clinical severity and procedure. Viscoelastic testing can help in centres with validated liver or major-haemorrhage algorithms but is not a universal gold standard.

Phytomenadione is appropriate when deficiency or VKA effect is plausible and is safe enough not to withhold solely because liver disease also exists. In life-threatening warfarin bleeding, four-factor PCC provides rapid factors while intravenous vitamin K sustains reversal. PCC is not routine correction for non-bleeding cirrhosis and carries thrombosis risk. After stabilisation, address nutrition, cholestasis, antibiotics, alcohol-related disease, portal hypertension and anticoagulant indication, and ensure thromboprophylaxis is reconsidered rather than assuming an elevated INR is protective.

Key points

Vitamin K deficiency typically prolongs PT first because factor VII has the shortest half-life; severe deficiency can prolong both PT and APTT and cause mucosal, gastrointestinal, operative or intracranial bleeding.
First-line assessment is medication and nutrition history, FBC and film, PT, APTT, fibrinogen, renal and liver profiles, bilirubin pattern and evaluation for cholestasis, malabsorption, antibiotics, warfarin, DIC and active bleeding.
A prompt PT improvement after phytomenadione supports deficiency, whereas non-correction suggests hepatocellular failure, ongoing VKA effect, consumption or another defect; do not delay emergency haemostasis to use this as a diagnostic test.
Cirrhosis creates rebalanced haemostasis: INR measures selected procoagulant factors but not reduced natural anticoagulants, high VWF, platelet function or fibrinolysis and does not reliably predict procedure bleeding.
Do not give plasma merely to normalise INR in stable non-bleeding liver disease. Treat the bleeding source and correct clinically relevant platelets or fibrinogen under a procedure or major-haemorrhage protocol.
For severe or life-threatening VKA-related bleeding, use four-factor PCC at the product-specific weight and pretreatment-INR dose plus phytomenadione 5–10 mg by slow intravenous injection.
For suspected nutritional or cholestatic deficiency without life-threatening bleeding, oral or slow intravenous phytomenadione is selected by urgency and absorption; recheck PT and address the cause.
Patients with cirrhosis still need VTE risk assessment. Use mechanical or pharmacological prophylaxis and therapeutic anticoagulation from individual thrombosis, platelet, bleeding, renal and variceal risk, not from INR alone.

02AetiologyUnderlying causes, associations and risk factors, with why each one matters.

Reduced vitamin K delivery

Poor intake, malabsorption, cholestasis, prolonged broad-spectrum antibiotics and biliary or pancreatic disease reduce absorption or microbial supply of fat-soluble vitamin K.

Vitamin K antagonism

Warfarin blocks vitamin K recycling, while selected cephalosporins and other medicines can add impaired synthesis or platelet effects in vulnerable patients.

Hepatocellular and portal disease

Acute liver failure, cirrhosis and severe hepatic injury reduce procoagulant and anticoagulant proteins, thrombopoietin and clearance while portal hypertension drives thrombocytopenia and variceal bleeding.

03PathophysiologyThe causal sequence from the underlying abnormality to symptoms and harm.

1
Failed gamma-carboxylation
Vitamin K deficiency produces under-carboxylated factors II, VII, IX and X and proteins C and S, impairing calcium-dependent membrane binding and thrombin generation.
2
Early PT prolongation
Factor VII has a short half-life, so PT and INR usually become abnormal before APTT in vitamin K deficiency or warfarin exposure.
3
Rebalanced liver haemostasis
Liver disease lowers clotting factors but also protein C, protein S and antithrombin, while VWF rises and ADAMTS13 falls, creating fragile balance rather than simple auto-anticoagulation.
4
Portal and systemic drivers
Varices, infection, renal failure, endothelial dysfunction, hyperfibrinolysis, low fibrinogen and procedural injury often determine bleeding more than INR itself.

04Clinical features and red flagsSymptoms, examination findings, patterns of presentation and time-critical warnings.

Deficiency context

Poor intake, diarrhoea, biliary obstruction, prolonged antibiotics or warfarin with new bruising and PT prolongation makes vitamin K deficiency plausible.

Liver failure context

Jaundice, ascites, encephalopathy, splenomegaly, low albumin and broader synthetic dysfunction indicate hepatic disease rather than isolated vitamin depletion.

Portal bleeding

Haematemesis, melaena, shock or encephalopathy in cirrhosis needs immediate upper-GI haemorrhage management regardless of the initial INR.

Thrombotic presentation

Painful unilateral leg swelling, pleuritic breathlessness or new portal-vein occlusion can occur despite prolonged PT in advanced liver disease.

Acute liver failureRed flag

New encephalopathy with jaundice, coagulopathy, hypoglycaemia or lactate elevation needs urgent liver-centre and critical-care escalation.

Red flags requiring action

Haematemesis or melaena with cirrhosis is a portal-hypertensive emergency until endoscopy establishes the source; correcting INR must not delay vasoactive therapy, antibiotics and endoscopic haemostasis.
New confusion, severe headache, focal deficit or reduced consciousness with coagulopathy requires urgent intracranial imaging and reversal or haemostatic support based on the actual cause.
Jaundice, hypoglycaemia, rapidly rising INR, encephalopathy, lactate elevation or kidney injury may represent acute liver failure and requires immediate specialist liver-centre discussion.

05InvestigationsWhat to request, why it matters and how to interpret it.

Investigation order

Read from the initial assessment onwards. Tests may run in parallel in urgent care; first-line, preferred, confirmatory, definitive and gold-standard labels appear only when the chapter explicitly states them.

01
First-line: FBC, PT, APTT and fibrinogenFirst stepFirst line
Why
Define the pattern, consequences and possible consumption alongside clinical bleeding.
Interpretation and limitations
Isolated PT prolongation fits early vitamin K deficiency; thrombocytopenia and low fibrinogen suggest advanced liver disease, DIC or major haemorrhage and require trends.
02
First-line: liver, renal and nutritional assessmentFirst line
Why
Separate impaired synthesis from malabsorption and identify modifiers of bleeding and medicine clearance.
Interpretation and limitations
Use bilirubin fraction, ALP, ALT, albumin, creatinine, history, imaging and targeted malabsorption tests. Albumin and INR reflect severity but are not bleeding tests in isolation.
03
Phytomenadione response
Why
Support vitamin K deficiency when diagnosis is uncertain and treatment is clinically appropriate.
Interpretation and limitations
Improvement in PT after correctly administered vitamin K supports deficiency; absent response raises severe liver failure, ongoing antagonist, DIC or an inhibitor. Mixed disease may partially correct.
04
Cause-specific anticoagulant testing
Why
Identify VKA or DOAC contribution before reversal and procedure decisions.
Interpretation and limitations
Use medication timing, INR for warfarin and validated drug-specific anti-Xa or dilute-thrombin methods when results will change urgent care; routine tests cannot quantify every DOAC.
05
Bleed-source and procedure assessment
Why
Find the anatomical lesion and the haemostatic components most likely to alter outcome.
Interpretation and limitations
Urgent endoscopy, CT, ultrasound or surgical assessment takes priority by site. Consider fibrinogen, platelets, renal failure and infection rather than using an arbitrary INR alone.

06Differential diagnosisRealistic alternatives and the features that help distinguish them.

Disseminated intravascular coagulation

A compatible systemic trigger, falling platelets and fibrinogen, rising D-dimer and evolving multiorgan injury support consumption, which may coexist with liver disease.

Direct anticoagulant effect

DOAC timing and renal function can explain bleeding with variable routine tests; a normal PT or APTT does not exclude clinically important drug concentration.

Factor inhibitor

An isolated APTT that fails to correct on mixing, especially with new soft-tissue bleeding, suggests acquired haemophilia rather than hepatic synthetic failure.

Primary platelet disorder

Mucosal bleeding with adequate fibrinogen and near-normal PT may reflect antiplatelet medicine, uraemia or inherited platelet dysfunction, sometimes superimposed on cirrhosis.

07ManagementImmediate care, first-line treatment, alternatives and escalation.

01Prolonged PTSeparate deficiency, drug and liver diseaseFirst stepPT or INR is newly prolonged with or without bleeding.

1Verify sampling, review warfarin and interacting medicines, nutrition, antibiotics, diarrhoea, cholestasis, alcohol and known hepatic disease.
2Check FBC, film, APTT, fibrinogen, liver and renal profiles and D-dimer when DIC is clinically plausible.
3Give vitamin K when deficiency is likely, repeat PT at an urgency-appropriate interval and investigate persistent or mixed abnormalities.

02Major VKA bleedingReverse immediately and durablyWarfarin contributes to life-threatening, organ-threatening or uncontrolled major haemorrhage.

1Stop warfarin, send urgent INR and crossmatch and begin resuscitation and anatomical haemostasis without waiting for the result when exposure is known.
2Give product-specific four-factor PCC by weight and pretreatment INR plus 5–10 mg phytomenadione by slow intravenous injection.
3Recheck INR and clinical haemostasis, monitor thrombosis and set a documented plan for if and when anticoagulation should restart.

03Bleeding in cirrhosisTreat source, not INRA person with liver disease has active gastrointestinal, procedural, traumatic or spontaneous bleeding.

1Activate the site-specific pathway, including vasoactive therapy, antibiotics and urgent endoscopy for suspected variceal bleeding.
2Correct shock, temperature and calcium and use platelets, fibrinogen or plasma only for a defined clinical deficit within the major-haemorrhage plan.
3Treat infection, renal failure and portal pressure and reassess frequently; avoid repeated plasma solely to reach a normal INR.

04Planned procedureMatch haemostasis to procedural riskAn invasive procedure is proposed in chronic liver disease or persistent vitamin K-related abnormality.

1Classify procedure site and compressibility, urgency, operator experience, platelet count, fibrinogen, renal function, infection and antithrombotic exposure.
2Correct demonstrated vitamin K deficiency and use liver or haemostasis specialist advice for high-risk procedures instead of a universal INR threshold.
3Arrange image guidance, local control, component availability and post-procedure observation proportionate to the actual bleeding consequence.

Key medicines and prescribing safety3 treatments · regimens, roles and cautions

Restores hepatic gamma-carboxylation when vitamin K is deficient or antagonised and provides sustained warfarin reversal.

Phytomenadione

For severe or life-threatening VKA-related haemorrhage, give 5–10 mg by slow intravenous injection with four-factor PCC; for non-emergency deficiency, choose an oral or intravenous dose from the current BNF or product protocol according to absorption and urgency, then recheck PT.

Intravenous administration must be slow because severe hypersensitivity is possible. Large doses can cause prolonged warfarin resistance; do not expect vitamin K to correct loss of hepatic synthetic capacity.

Rapidly replaces vitamin K-dependent factors during major VKA bleeding or emergency surgery where immediate reversal is necessary.

Four-factor prothrombin-complex concentrate

For Beriplex urgent VKA reversal, dose factor IX units/kg by pretreatment INR with weight capped at 100 kg: INR 2.0–3.9, 25 units/kg; INR 4.0–6.0, 35 units/kg; INR above 6.0, 50 units/kg; give vitamin K concurrently.

This is product-specific and not routine liver-disease correction. Monitor haemostasis, INR, thrombosis, DIC and hypersensitivity; Beriplex contains heparin and is contraindicated in a known HIT history.

Provides concentrated fibrinogen when depletion materially impairs haemostasis in advanced liver disease, DIC or major blood loss.

Cryoprecipitate

For clinically significant bleeding with low fibrinogen, give two pooled adult doses intravenously under the major-haemorrhage protocol, then repeat fibrinogen and clinical assessment before further replacement.

Use a clinically relevant threshold and treatment target rather than routine prophylaxis. Balance thrombosis, component exposure and fluid status, and obtain anatomical source control.

08ComplicationsImportant consequences, why they occur and why they matter clinically.

Portal-hypertensive haemorrhage

Variceal bleeding reflects venous pressure and collateral rupture as well as haemostatic disturbance and needs urgent portal-source treatment.

Procedure-related bleeding

Low platelets, low fibrinogen, renal failure, infection and high-risk anatomy may combine during biopsy, surgery or line placement; INR alone predicts poorly.

Venous and portal thrombosis

Cirrhosis does not protect from DVT, pulmonary embolism or portal-vein thrombosis because natural anticoagulants and flow are also impaired.

Treatment-related thrombosis or overload

PCC and unnecessary factor replacement can tip balance toward thrombosis, while repeated plasma can cause portal-pressure increase and circulatory overload.

09Monitoring and follow-upTreatment response, safety checks and longer-term review.

After vitamin K, repeat PT or INR on a timescale determined by bleeding and route, and investigate non-response rather than giving repeated empirical doses indefinitely.
During major haemorrhage, monitor haemodynamics, haemoglobin, platelets, fibrinogen, temperature, ionised calcium, renal function and visible or imaging-defined blood loss.
After PCC, assess clinical haemostasis and INR promptly and monitor for myocardial, cerebral, venous or portal thrombosis, especially when liver disease already creates prothrombotic risk.
In chronic liver disease, follow the underlying disease, portal complications, nutrition, infection and renal function; serial INR alone is not a haemostasis monitoring strategy.
At discharge, document anticoagulant changes, vitamin K cause, planned nutrition or biliary treatment, VTE prevention and ownership of repeat blood tests.

10Special situationsVariants, exceptions and circumstances that change the usual approach.

INR was built for warfarin

Its standardisation does not capture the parallel fall in hepatic natural anticoagulants or the rise in VWF during cirrhosis.

Factor VII moves first

Its short half-life explains why PT becomes abnormal before APTT during early vitamin K depletion or VKA therapy.

Varices are pressure lesions

Haemostatic support may be needed, but vasoactive treatment and urgent endoscopic source control determine whether portal bleeding stops.

Cirrhosis does not anticoagulate

DVT, pulmonary embolism and portal thrombosis remain possible because anticoagulant proteins and venous flow are also reduced.

Plasma has a physiological cost

Large volumes can cause circulatory overload and may raise portal pressure while producing limited INR change in severe liver disease.

11Common pitfallsFrequent interpretation and management errors.

01
Equating a high INR in cirrhosis with protection from thrombosis.
02
Transfusing plasma solely to reach a normal INR.
03
Delaying endoscopy while attempting laboratory correction.
04
Assuming vitamin K will correct severe hepatocellular failure.
05
Using PCC routinely before low-risk procedures in cirrhosis.
06
Forgetting malabsorption when oral vitamin K does not work.