195 Acne keloidalis nuchae: A population-based epidemiologic study in central and northeastern Pennsylvania

Abstract

Acne keloidalis nuchae (AKN) is reported to mainly occur in adult men of African descent. However, it has been our clinical observation that a large portion of our patients with AKN is not African-American (AA). This study is the largest analysis of demographic and epidemiologic data in non-AA patients with AKN. A retrospective search of the Geisinger Health System EPIC database was performed to identify patients with AKN between 2011-2018. 110 patients were identified and their demographic and epidemiologic data were obtained and analyzed. Comparisons between AA and non-AA groups were performed using the Chi-square or Fisher’s exact test, and two-sample T-test or Wilcoxon rank sum test. Mean age at diagnosis was 36.1 years old, most patients were male (88.2%), Caucasian (59.1%), and had an average BMI of 33.5 kg/m2 (32.9 vs. 33.8 for AA and non-AA respectively, p=0.62). A subset of patients had diabetes (10% vs. 5.9% for AA and non-AA respectively, p=0.46), hyperlipidemia (10% vs. 20.6% for AA and non-AA respectively, p=0.15), were current or former smokers (31.6% vs. 34.3% for AA and non-AA respectively, p=0.66) and took anticonvulsants (10% and 19.1% of AA and non-AA respectively, p=0.21). The most common treatments used for AKN were oral tetracyclines (54.1%), topical corticosteroids (61.2%) and topical antibiotics (41.2%), with non-AAs more likely to be treated with topical antibiotics (p=0.0004). Most patients with AKN in central and northeastern Pennsylvania are Caucasian males. This study identifies similarities and differences between AAs and non-AAs with AKN. Our results serve as a reminder that AKN should be on the differential for chronic scarring folliculitis and perifolliculitis of the posterior scalp and neck in Caucasians and highlight the potential association between obesity and AKN.