Hermansky Pudlak syndrome: an unusual form of procto-colitis

Hermansky-Pudlak syndrome (HPS) is a rare autosomal recessive disorder consisting of oculocutaneous albinism, platelet dysfunction and systemic complications associated with lipofuscin deposition in the reticuloendothelial system. HPS has been associated with a granulomatous enterocolitis with pathologic features suggestive of Crohn's disease. It remains uncertain if HPS represents a truly distinct form of granulomatous enterocolitis. We report a series of two patients with HPS treated in Puerto Rico, and the results from medical and surgical intervention for gastrointestinal disease. Our experience with HPS patients has shown the difficult management of perineal disease similar in the management of Crohn's. However, complications from the bleeding diathesis necessitate caution during surgery and potential anesthesia complications. Furthermore, avoidance of a perineal wound is preferred, and when possible, ileostomies have fewer complications than colostomies as they do not involve the small bowel.

Mutation screening of the TYR and P gene in three patients with oculocutaneous albinism / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To identify the mutations of the tyrosinase gene (TYR) and P gene in patients with oculocutaneous albinism (OCA).</p><p><b>METHODS</b>Polymerase chain reaction (PCR) and denaturing high performance liquid chromatography (DHPLC) were applied to detect the mutations in all exons of TYR gene and P gene. Then DNA sequencing and restriction endonuclease analysis were used to confirm the mutations detected by DHPLC. Novel mutations were screened in 100 unrelated persons with normal phenotypes to exclude the possibility of polymorphism.</p><p><b>RESULTS</b>Two mutations were detected in the P gene of the three patients and none in TYR gene. Heterozygous mutation of T450M in exon 13 of the P gene was detected in patient 1. Patient 2 had a heterozygous mutation of T450M in exon 13 and a heterozygous mutation of G775R in exon 23 of the P gene. Patient 3 had a heterozygous mutation of G775R as well. Restriction endonuclease analysis of the P gene exon 13 showed that the Oli I site had partly disappeared resulting from the heterozygous mutation T450M in patient 1 and patient 2, but not in 100 unrelated individuals. The heterozygous mutation T450M is a novel mutation.</p><p><b>CONCLUSION</b>Gene diagnosis of OCA can be carried out effectively by combining PCR, DHPLC, DNA sequencing and restriction endonuclease analysis.</p>

Color vision in patients with the Hermansky-Pudlak syndrome

PURPOSE: To study color vision in patients with oculocutaneous albinism (OCA) METHODS: We evaluated color vision in 42 patients with OCA using the HRR color plates. Sixty seven percent of the patients had the Hermansky-Pudlak syndrome (HPS), diagnosed genetically or clinically. The remaining patients had unknown mutations leading to OCA. RESULTS: 47.6 of patients of OCA of all types included had a color vision defect. Of these, 55 were female and 45 were male patients. 50 of patients with the HPS (all types) had a color vision deficit. 42.9 of patients with OCA of unknown type had color weakness. 57.1 had normal color vision. CONCLUSIONS: Results suggest that many patients with OCA and the HPS have a mild red-green color perception deficiency that is not a sex linked trait. The prevalence of color vision deficits in our study population increased with decreasing visual acuity