Hidradenitis suppurativa (HS) is an inflammatory skin disease affecting approximately 1% of people worldwide. HS can cause a severe decline in quality of life, with chronic, painful lesions (affected patches) in hair bearing sites such as armpits and buttocks. This study, performed by researchers from Turkey and Germany, looked at the role of a gene called MEFV gene in HS, using a group of 119 people with the disease. The researchers identified some clinical characteristics (e.g. severity, presence of other diseases) associated with complex HS, such as the patient having more severe HS and an additional inflammatory condition (e.g. severe acne, arthritis or Familial Mediterranean Fever (FMF, caused by mutations in the MEFV gene)). Patients were categorized into two subgroups, those with complex HS (38% of the 119 people) and those with noncomplex HS. The authors compared the percentage of MEFV mutations in the people with complex HS to those with noncomplex HS. Most of the patients in the complex HS group were men. The disease started earlier in the complex HS group when compared to HS patients in general, and a diagnosis of FMF was more common among HS patients when compared to the general population. The frequency of MEFV mutations in the group of patients with complex HS was higher than that in people without HS. The results of this study suggest that MEFV gene mutations may be a risk factor in a subset of HS patients, and this understanding may be important for the development of new treatments.