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Epidemiology and clinical features of keloids in Black Africans: a nested case-control study from Yaoundé, Cameroon
Emmanuel A Kouotou1,2,3, Jobert R Nansseu4, Edwige Omona Guissana1,3
1Yaoundé University Teaching Hospital, Yaoundé, Cameroon.
Background:
Keloids are a common presenting complaint in Black Africans but remain poorly documented in these populations. The aim of our study was to describe the epidemiological and clinical profiles of patients with keloids seen at dermatology outpatient consultations in Yaoundé (Cameroon) and to determine driving factors of keloid occurrence.
Methods:
This was a 1 : 2 case-control study conducted from February to May 2016 at the dermatology unit of five health facilities in Yaoundé, Cameroon. Cases were patients with black skin and diagnosed with keloids while controls had no keloid scar, paired to cases according to age and sex. The diagnosis of keloid was based on clinical history and findings.
Results:
Of 2,940 patients seen during the study period, 102 (54.9% females) had keloids, hence a prevalence of 3.5% (95% confidence interval [CI]: 2.8-4.2). The most affected age group was ≥25 years (69.6%). Lesions at the origin of keloids were mostly traumatic (66.7%). In 68 patients (66.7%), keloid scars were associated with pruritus. The presternal region was the predominant localization (26.5%). Existence of a family history of keloids was significantly associated with presence of keloids (adjusted odds ratio: 4.2, 95% CI: 2.4-7.2; P < 0.001).
Conclusions:
Keloids commonly affect black skin as recorded during dermatology consultations in Yaoundé, Cameroon. More often, they are secondary to skin trauma and seem to occur among those with a family history of keloids. Therefore, these people should be closely monitored accordingly.
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