A 30-year-old man comes to the office due to low back pain and stiffness for 2 months. His pain is worse in the morning and improves with activity. The patient has also had intermittent diarrhea and lower abdominal pain for the past 3 months. He tried ibuprofen, which helped his back pain but made his diarrhea worse. He has not traveled outside the United States. The patient has been sexually active with the same female partner for 2 years. He has no other medical problems and does not use tobacco, alcohol, or recreational drugs. Vital signs are normal. Physical examination shows limited spine flexion and tenderness in the lower back. Laboratory studies show anemia and thrombocytosis. Stool cultures are negative. Plain radiographs reveal sacroiliac joint inflammation. Which of the following is the most likely cause of this patient's symptoms?

Question

A 30-year-old man comes to the office due to low back pain and stiffness for 2 months.  His pain is worse in the morning and improves with activity.  The patient has also had intermittent diarrhea and lower abdominal pain for the past 3 months.  He tried ibuprofen, which helped his back pain but made his diarrhea worse.  He has not traveled outside the United States.  The patient has been sexually active with the same female partner for 2 years.  He has no other medical problems and does not use tobacco, alcohol, or recreational drugs.  Vital signs are normal.  Physical examination shows limited spine flexion and tenderness in the lower back.  Laboratory studies show anemia and thrombocytosis.  Stool cultures are negative.  Plain radiographs reveal sacroiliac joint inflammation.  Which of the following is the most likely cause of this patient's symptoms?

Quizplus · Accepted Answer

This patient likely has inflammatory bowel disease (IBD) complicated by spondylarthritis. IBD, which includes Crohn disease and ulcerative colitis, frequently presents in patients age 15-40 and again at age 50-80. Both Crohn disease and ulcerative colitis have multiple extraintestinal manifestations, including arthritis, eye (eg, uveitis, episcleritis) and skin (eg, pyoderma gangrenosum) involvement, and hepatobiliary disease (eg, primary sclerosing cholangitis). Arthritis occurs in up to 45% of patients with IBD and can involve axial (eg, spine) or peripheral (eg, knee) joints. Patients with spondylarthritis or sacroiliitis commonly report prolonged stiffness and low back or buttock pain that improves with activity. There are no specific tests for the diagnosis of IBD-associated arthritis. Nonsteroidal anti-inflammatory drugs (NSAIDs) can relieve arthritis symptoms but exacerbate the underlying bowel disease. Consequently, although NSAIDs are frequently tried, many of the medications (eg, sulfasalazine) used to treat the bowel disease itself are also used to treat joint disease. (Choice A) Gluten-sensitive enteropathy (celiac disease) causes malabsorptive diarrhea, which is frequently greasy. It is not worsened by NSAID administration, and thrombocytosis is uncommon. The characteristic cutaneous finding is dermatitis herpetiformis. (Choice C) Gastrointestinal (GI) paraneoplastic syndromes include secretory, watery diarrhea due to vasoactive intestinal peptide-secreting tumors, carcinoid syndrome (cutaneous flushing, watery diarrhea, respiratory difficulties) due to carcinoid tumors, and gastroparesis due to autoimmune destruction of GI neurons caused by a variety of tumors. None of these syndromes would explain the arthritis or the worsening with ibuprofen. (Choice D) Reactive arthritis may follow infectious diarrhea caused by Shigella, Salmonella, Yersinia, Campylobacter, or Clostridium difficile. It typically occurs within 2-3 weeks of the onset of diarrhea and is often characterized by concomitant urethritis, conjunctivitis/uveitis, malaise, and cutaneous findings (eg, keratoderma blennorrhagica, balanitis circinata). (Choice E) Rheumatoid arthritis is more commonly associated with peripheral arthritis (eg, metacarpophalangeal joints), and the lumbar or sacral spine is rarely involved. Moreover, although rheumatoid arthritis can involve multiple other organ systems, GI tract involvement is rare. (Choice F) Spinal osteomyelitis can also present with subacute worsening of back pain, but it is frequently worse at night and improved with rest (not activity). Educational objective: Inflammatory bowel disease is frequently complicated by arthritis, which occurs in up to 45% of patients and can involve axial or peripheral joints. Treatment with nonsteroidal anti-inflammatory drugs may exacerbate the underlying disease. References: Extraintestinal manifestations of inflammatory bowel disease. (http://www.ncbi.nlm.nih.gov/pubmed/26154136) Extraintestinal manifestations of inflammatory bowel disease: do they influence treatment and outcome? (http://www.ncbi.nlm.nih.gov/pubmed/21734777) The joint-gut axis in inflammatory bowel diseases. (http://www.ncbi.nlm.nih.gov/pubmed/21122514)

A 30-Year-Old Man Comes to the Office Due to Low