Vitamin K Deficiency

Etiology

Vitamin K Deficiency

Inadequate Dietary Vitamin K Intake
- Ethanol Abuse (see Ethanol)
- Long-Term Total Parenteral Nutrition (TPN) (see Total Parenteral Nutrition)
- Malnutrition (see Malnutrition)
Intestinal Vitamin K Malabsorption
- Ascaris (see Ascariasis)
- Biliary Disease: due to impaired bile acid secretion into small intestine
  - Cholestasis (see Elevated Liver Function Tests)
  - Common Bile Duct Obstruction
    - Biliary Stricture
    - Cholangiocarcinoma (see Cholangiocarcinoma)
    - Choledocholithiasis (Biliary Stone) (see Choledocholithiasis)
  - Primary Biliary Cirrhosis (PBC) (see Primary Biliary Cirrhosis)
  - T-Tube Drainage
- Celiac Disease (see Celiac Disease)
- Cholestyramine (see Cholestyramine): binds to bile acids
- Chronic Pancreatitis (see Chronic Pancreatitis)
- Crohn’s Disease (see Crohn’s Disease)
- Intestinal Bacterial Overgrowth
- Short Bowel Syndrome (see Short Bowel Syndrome): from multiple prior bowel resections
- Tropical Sprue
- Ulcerative Colitis (UC) (see Ulcerative Colitis)
Loss of Vitamin K Storage Sites
- Liver Disease/Cirrhosis (see Cirrhosis)
Drugs: mechanism of vitamin K deficiency from these agents is unknown
- Barbiturates (see Barbiturates)
- Phenytoin (Dilantin) (see Phenytoin)
- Cefamandole
- Cefoperazone (see Cefoperazone)
- Isoniazid (INH) (see Isoniazid)
- Rifampin (see Rifampin)
- Salicylates (see Salicylates)
- Sulfonamides (see Sulfonamides): some agents have been implicated
Other
- Chronic Illness
- Cystic Fibrosis (CF) (see Cystic Fibrosis)
- Disseminated Intravascular Coagulation (DIC) (see Disseminated Intravascular Coagulation, [[Disseminated Intravascular Coagulation]]): in severe cases
- Massive Transfusion

Vitamin K Antagonism

Coumadin (Warfarin) (see Coumadin): inhibits the hepatic gamma carboxylation of glutamic acid
Coumadin-Containing Herbs
- Chamomile (Matricaria Recutita, Chamaemelum Mobile) (see Chamomile)
- Fenugreek (Trigonella Foenum-Graecum) (see Fenugreek)
- Horse Chestnut (Aesculus hippocastanum)
- Motherworth (Leonurus Cardiaca)
- Red Clover (Trifolium Pratense)
High-Dose Vitamin E (see Vitamin E)

Clinical Manifestations

Hematologic Manifestations

Prolonged PT/INR (see Coagulopathy): vitamin K-dependent clotting factor activity is more reflected in the PT/INR than in the PTT
Factor II/VII/IX/X Levels: decreased
- If factor V is also low, as well, this suggests a defect in hepatic synthetic function and cannot be attributed to vitamin K deficiency alone

Rheumatologic Manifestations

Increased Risk of Fractures/Osteoporosis (see Osteoporosis): due to role of vitamin K in the synthesis of bone proteins, such as osteocalcin

Other Manifestations

Hemorrhagic Disease of the Newborn
- Early Onset: intracranial and retroperitoneal bleeding (occurring at 1-7 days postpartum)
- Late Onset (occuring as late as 3 months postpartum)
- To prevent this in newborns (who have minimal hepatic stores of vitamin K at birth), vitamin K is given prophylactically soon after birth

Treatment

Oral Vitamin Vitamin K1 (Phytonadione) (see Vitamin K): 5-10 mg /day
- Excellent absorption
- Expected improvement in INR within 1 day
Subcutaneous Vitamin K
- Absorption is erratic
Intravenous Vitamin K1 (Phytonadione) (see Vitamin K): 1 mg/day
- Faster normalization of INR than PO dosing
- Side Effects
  - Anaphylaxis (see Anaphylaxis)

MD Nexus

Vitamin K Deficiency

Etiology

Vitamin K Deficiency

Vitamin K Antagonism

Clinical Manifestations

Hematologic Manifestations

Rheumatologic Manifestations

Other Manifestations

Treatment

References