A 34-year-old man is evaluated in the clinic due to easy bruising. The patient says that even minor trauma causes a bruise and that he sometimes has spontaneous bruising over his legs. He has also been experiencing generalized fatigue, poor appetite, and dull pain and stiffness in his lower back and joints at night. The patient has a history of Crohn disease that required a partial bowel resection a year ago. Three months ago, he was treated with oral antibiotics for a perianal fistula. His mother died of colon cancer when she was 56. Physical examination shows several large ecchymoses on his lower extremities. Which of the following is the most likely diagnosis?
Crohn disease typically presents with prolonged diarrhea and abdominal pain. Transmural inflammation of the bowel wall may result in the formation of fistulas, abscesses, and fibrotic strictures. Extraintestinal manifestations can include ankylosing spondylitis and peripheral arthritis, which often manifest with low back pain and joint stiffness that is worse at night. Constitutional symptoms (eg, low-grade fever, fatigue), malabsorption, and weight loss are also common.
The terminal ileum is frequently involved in Crohn disease. Bile acids, which are necessary for the absorption of fat and other nutrients, are normally reabsorbed in the terminal ileum, recycled in the liver, and then reused in the absorptive process. When the terminal ileum is inflamed or resected, bile acids are lost with feces. Loss of bile acids causes fat malabsorption, which may lead to deficiencies in fat-soluble vitamins (A, D, E, K).
Vitamin K is a cofactor for several carboxylase enzymes that are necessary for coagulation factor II, VII, IX, and X activation. Coagulation disorders such as vitamin K deficiency typically result in easy bruising, large hematoma formation in deep tissues and joints (eg, hemarthrosis) after minor trauma, and prolonged bleeding after surgery.
(Choice A) Autoimmune hepatitis is more common in women than in men and is more often associated with ulcerative colitis than Crohn disease. Patients may be asymptomatic or present with signs of liver dysfunction (eg, jaundice, hepatosplenomegaly, ascites), including easy bruising and gastrointestinal bleeding due to coagulopathy.
(Choice C) Factor VIII deficiency (hemophilia A) is an X-linked recessive coagulation disorder that can manifest as early as birth. Typical features include easy bruising, hemarthrosis, and prolonged bleeding after surgery (eg, tooth extraction).
(Choice D) Immune thrombocytopenic purpura is characterized by autoimmune destruction of platelets and is often associated with viral infections. Platelet abnormalities typically cause superficial microhemorrhages such as petechiae and mucosal bleeding (eg, epistaxis, gingival bleeding).
(Choice E) Leukocytoclastic vasculitis can be associated with antibiotic use (eg, penicillins, cephalosporins) or viral hepatitis infection; however, patients usually develop nonblanching petechiae or palpable purpura without significant bleeding.
Educational objective:
Crohn disease with ileal resection or extensive ileal involvement can cause bile acid malabsorption, which may lead to impaired absorption of fat-soluble vitamins (A, D, E, K). Vitamin K deficiency can result in impaired coagulation with easy bruising, large hematoma formation in deep tissues and joints (eg, hemarthrosis) after minor trauma, and prolonged bleeding after surgery.