ABSTRACT
Background
Oculocutaneous albinism (OCA) could be either non-syndromic or syndromic. There are significant challenges in clinically recognizing and differentiating Hermansky-Pudlak syndrome (HPS) from non-syndromic OCA.
Materials and Methods
In a prospective consecutive case series, 63 patients (less than 18 years old) with a molecular genetic diagnosis of albinism (except OCA1A), Ocular albinism (OA) and Hermansky-Pudlak syndrome seen over a 3-year period were evaluated and analyzed. Hair colour, iris colour was graded, compared and correlated with the degree of fundus pigmentation and foveal development.
Results
A total of 63 patients were evaluated. Forty-five patients had non-syndromic OCA (11 OCA1B, 24 OCA2, 9 OCA4, and 1 OCA6), 5 patients had OA and 13 patients had HPS. All 3 BLOC-related HPS categories were seen (1 with BLOC1, 7 with BLOC-2 and 5 with BLOC-3 related HPS). All patients with OA were hyperopic, had darker fundus pigmentation, but had poor foveal development. All HPS patients had lighter fundus pigmentation. The degree of fundus pigmentation correlated positively with the iris pigmentation and also with the foveal development only in OCA2.
Conclusions
Careful observation of the phenotype by comparison of the skin, hair, iris colour, with the degree of fundus pigmentation and foveal development may help clinically differentiate HPS from OCA patients of Chinese ethnicity even in the absence of any bleeding tendency.
Acknowledgments
We sincerely acknowledge our hospital directors Mrs. Sharon Li and Prof Dennis Lam for their phenomenal support to our work at the International albinism clinic. We also sincerely thank all the albinism and HPS patients and their families.
Disclosure statement
The authors report no conflicts of interest. The authors alone are responsible for the content and writing of this article.
Correction Statement
This article has been corrected with minor changes. These changes do not impact the academic content of the article.