When people with psoriasis use TNF-alpha inhibitors, they sometimes develop new skin lesions. Doctors often call these cases paradoxical psoriasis because the medication seems to cause a flare-up of the original disease. However, some of these reactions might actually be something else entirely.
A small series of six patients showed that these skin problems were actually caused by a bacteria called Staphylococcus aureus. These infections can look very similar to psoriasis, making it hard for doctors to tell them apart at first glance. In every case in this group, the symptoms cleared up once the patients received antibiotics and topical treatments.
Because these infections can lead to the end of a patient's current treatment plan, it is important to check the skin closely. Doctors may need to look for signs of infection rather than assuming a flare-up. While this study only looked at six people, it highlights why a careful look at the skin can help patients get the right treatment.