Acquired progressive kinking of the hair. Clinical features, pathological study, and follow-up of 7 patients

Background: Acquired progressive kinking of the hair (APKH) is a relatively rare condition, with fewer than 20 cases reported in the literature. Whether APKH is a separate entity or a variety of androgenetic alopecia is still controversial. This study reviews the clinical and pathological features and long-term follow-up of 7 patients with APKH. Observations: Since January 1989, we have diagnosed APKH in 7 males aged 15 to 22 years. All patients had strong family history for androgenetic alopecia. Hair kinking affected the frontotemporal region and/or the vertex where the hair appeared curly, frizzy, and lusterless. The pathological features of the affected scalp were consistent with the diagnosis of the early stages of androgenetic alopecia. In all patients, APKH evolved into androgenetic alopecia during the follow-up period. Mean follow-up was 4.5 years (range, 2-9 years). Treatment with topical minoxidil did not prevent development of hair-thinning in the scalp areas affected by hair kinking. Conclusions: The term acquired progressive kinking of the hair encompasses a number of conditions characterized by acquired curling of the scalp hair. Acquired hair kinking on the androgen-dependent areas of the scalp represents a modality of onset of androgenetic alopecia associated with poor prognosis.