now appeals. For the following reasons, we reverse in part, vacate in part, and remand.
FACTS AND PROCEEDINGS BELOW Carmona was diagnosed with psoriasis when he was twelve or thirteen years old. Psoriasis is a skin disease characterized by thickened patches of inflamed, red skin, often covered by silvery scales. American Medical Association, Encyclopedia of Medicine 830 (Charles B. Clayman ed., Random House 1989). Although individual attacks of psoriasis can be completely relieved, the disease itself is not usually curable, and it tends to recur in attacks of varying severity. Id. Carmona began working as a flight attendant at Southwest in 1991.
In 1998, Carmona was diagnosed with psoriatic arthritis, which is a condition that develops in about thirty-five percent of people who have psoriasis. Psoriatic arthritis causes painful swelling and stiffness in the joints during attacks of psoriasis on the surface of the skin. During flare-ups of his psoriatic arthritis, Carmona cannot walk or move around without great pain. It also makes it harder for him to sleep. Carmona’s psoriatic arthritis flares up three or four times every month, and each flare-up lasts for three or four days. In other words, Carmona spends anywhere from about one-third to about one-half of each month unable to move without a great deal of pain. He filed for intermittent Family and Medical Leave Act (FMLA) leave so that he could be excused from work during these flare-ups. Southwest’s third-party FMLA administrator, Broadspire Administrator Services, Inc. (Broadspire), granted this leave in 1998. Broadspire renewed the leave periodically until April 2005, when it found that Carmona had not worked enough hours to be eligible for renewal.