When former Alabama linebacker Rolando McClain announced on March 10 that he has waged a private battle against Crohn’s disease since his freshman year of high school, plenty of reporters turned to Google for an explanation.

Crohn’s is an intestinal inflammation condition affecting an estimated 500,000 Americans, particularly adolescents and young adults. Conditions that cause intestinal swelling are relatively common (irritable bowel syndrome is one related condition), so Crohn’s is a diagnostic challenge.

To make it more difficult, the primary symptoms are far from any that suggest a clear-cut diagnosis: diarrhea and abdominal pain. Other symptoms include rectal bleeding, fever, weight loss and arthritis.

Quality of life is a challenge because Crohn’s patients are liable to flare-ups at any time without warning or cause. These episodes can be brief and fleeting or painfully long, and medicines are not always able to keep pace with the flare-ups.

The most common complication of Crohn’s is intestinal obstruction, which is caused by the inflammation and the development of scar tissue. While medication is often an effective tool to relieve intestinal blockages, surgery can be necessary.

Aside from the daily quality of life issues, there are long-term nutritional concerns that come about from Crohn’s. The inflammation can sometimes cause malabsorption, which can lead to deficiencies of life’s key building blocks like vitamins and proteins. Poor absorption of some vitamins, such as B12, can lead to problems with other organ systems, such as the nervous system.

Treatment of Crohn’s is a challenge, and there is no cure. Many patients do well with medication (McClain said he takes four or five pills a day to control his condition), though surgery is eventually required in approximately two-thirds of patients.

Medications aim to control symptoms (and therefore maximize quality of life) and reduce the number of flare-ups while addressing the nutritional deficiencies that result from the disease. They also try to control the intestinal swelling, and, as a result, blockages.

When medicines fail, the surgical alternative is an option, but not a cure. The cause of Crohn’s disease is unknown—one dominating hypothesis is that it an autoimmune disorder—and Crohn’s has been known to recur in patients who have had surgery, which often involves removal of part of the diseased intestine.

McClain’s announcement did not appear to have any effect on his prospects for stardom in the National Football League. Draft experts continue to project McClain, who said his condition has been well-managed, as a first-round pick.