Received: 29 November 2018
Accepted: 15 January 2019
First Online: 1 February 2019
Ethics approval and consent to participate
: Ethical approval was obtained from the Ethics and Research Committee of the University of Calabar Teaching Hospital, Nigeria, before collection of samples. Informed consent was obtained from the subjects before recruiting them for the study.
: Written informed consent was obtained from the participants for publication of their individual details and accompanying images in this manuscript. The consent form is held by the authors and is available for review by the Editor-in-Chief.
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