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Giant melanosomes in melanocytes

MedGen UID:
812551
Concept ID:
C3806221
Finding
Synonym: Macromelanosomes
 
HPO: HP:0005592

Definition

The presence of large spherical melanosomes (1 to 6 micrometer in diameter) in the cytoplasm of melanocytes. [from HPO]

Term Hierarchy

CClinical test,  RResearch test,  OOMIM,  GGeneReviews,  VClinVar  
  • CROGVGiant melanosomes in melanocytes

Conditions with this feature

Chédiak-Higashi syndrome
MedGen UID:
3347
Concept ID:
C0007965
Disease or Syndrome
Chediak-Higashi syndrome (CHS) is characterized by partial oculocutaneous albinism, immunodeficiency, and a mild bleeding tendency. Approximately 85% of affected individuals develop the accelerated phase, or hemophagocytic lymphohistiocytosis, a life-threatening, hyperinflammatory condition. All affected individuals including adolescents and adults with atypical CHS and children with classic CHS who have successfully undergone allogenic hematopoietic stem cell transplantation (HSCT) develop neurologic findings during early adulthood.
Ocular albinism, type II
MedGen UID:
120643
Concept ID:
C0268505
Disease or Syndrome
Aland Island eye disease (AIED) is an X-linked recessive retinal disease characterized by fundus hypopigmentation, decreased visual acuity, nystagmus, astigmatism, protan color vision defect (303900), progressive myopia, and defective dark adaptation. Although AIED has been referred to as a form of albinism, there is no misrouting of the optic nerves, which excludes it from the formal diagnosis of classic albinism (King et al., 2001).
Ocular albinism, type I
MedGen UID:
90991
Concept ID:
C0342684
Disease or Syndrome
Ocular albinism type I (OA1) is the most common form of ocular albinism. Clinical presentation of OA1 in Caucasians is characterized by nystagmus, impaired visual acuity, iris hypopigmentation with translucency, albinotic fundus, macular hypoplasia, and normally pigmented skin and hair. Carrier females usually have punctate iris translucency and a mottled pattern of fundus pigmentation. In contrast to Caucasian patients, black or Japanese patients with OA1 often have brown irides with little or no translucency and varying degrees of fundus hypopigmentation, the so-called 'nonalbinotic fundus' (summary by Xiao and Zhang, 2009).
Ocular albinism with late-onset sensorineural deafness
MedGen UID:
337149
Concept ID:
C1845069
Congenital Abnormality
Ocular albinism is a genetic condition that primarily affects the eyes. This condition reduces the coloring (pigmentation) of the iris, which is the colored part of the eye, and the retina, which is the light-sensitive tissue at the back of the eye. Pigmentation in the eye is essential for normal vision.\n\nOcular albinism is characterized by severely impaired sharpness of vision (visual acuity) and problems with combining vision from both eyes to perceive depth (stereoscopic vision). Although the vision loss is permanent, it does not worsen over time. Other eye abnormalities associated with this condition include rapid, involuntary eye movements (nystagmus); eyes that do not look in the same direction (strabismus); and increased sensitivity to light (photophobia). Many affected individuals also have abnormalities involving the optic nerves, which carry visual information from the eye to the brain.\n\nUnlike some other forms of albinism, ocular albinism does not significantly affect the color of the skin and hair. People with this condition may have a somewhat lighter complexion than other members of their family, but these differences are usually minor.\n\nThe most common form of ocular albinism is known as the Nettleship-Falls type or type 1. Other forms of ocular albinism are much rarer and may be associated with additional signs and symptoms, such as hearing loss.

Recent clinical studies

Etiology

Margaryan NV, Gilgur A, Seftor EA, Purnell C, Arva NC, Gosain AK, Hendrix MJ, Strizzi L
Int J Mol Sci 2016 Mar 22;17(3):418. doi: 10.3390/ijms17030418. PMID: 27011171Free PMC Article
Ball NJ, Kho GT
J Cutan Pathol 2005 Sep;32(8):523-32. doi: 10.1111/j.0303-6987.2005.00376.x. PMID: 16115049
Cox NH, Malcolm A, Long ED
Dermatology 1997;194(3):213-6. doi: 10.1159/000246104. PMID: 9187835
Schneider BV, Schnyder UW
Arch Dermatol Res 1991;283(7):438-44. doi: 10.1007/BF00371779. PMID: 1801653
Abel EA, Reid H, Wood C, Hu CH
J Am Acad Dermatol 1985 Nov;13(5 Pt 1):761-8. doi: 10.1016/s0190-9622(85)70219-8. PMID: 4078071

Diagnosis

Margaryan NV, Gilgur A, Seftor EA, Purnell C, Arva NC, Gosain AK, Hendrix MJ, Strizzi L
Int J Mol Sci 2016 Mar 22;17(3):418. doi: 10.3390/ijms17030418. PMID: 27011171Free PMC Article
Shon W, Wada DA, Gibson LE, Flotte TJ, Scheithauer BW
J Cutan Pathol 2011 Nov;38(11):865-70. Epub 2011 Aug 8 doi: 10.1111/j.1600-0560.2011.01764.x. PMID: 21819442
Introne W, Boissy RE, Gahl WA
Mol Genet Metab 1999 Oct;68(2):283-303. doi: 10.1006/mgme.1999.2927. PMID: 10527680
Schallreuter KU, Frenk E, Wolfe LS, Witkop CJ, Wood JM
Dermatology 1993;187(4):248-56. doi: 10.1159/000247258. PMID: 8274781
Jimbow K, Horikoshi T
Am J Dermatopathol 1982 Oct;4(5):413-20. doi: 10.1097/00000372-198210000-00006. PMID: 6816084

Therapy

Shelley WB, Shelley ED, Burmeister V
J Am Acad Dermatol 1987 Jan;16(1 Pt 1):124-8. doi: 10.1016/s0190-9622(87)80175-5. PMID: 2948977
Abel EA, Reid H, Wood C, Hu CH
J Am Acad Dermatol 1985 Nov;13(5 Pt 1):761-8. doi: 10.1016/s0190-9622(85)70219-8. PMID: 4078071
Kanerva L, Niemi KM, Lauharanta J
Arch Dermatol Res 1984;276(1):2-11. doi: 10.1007/BF00412555. PMID: 6703775
Szekeres L, Orfanos CE
Dermatologica 1978;156(3):142-54. doi: 10.1159/000250911. PMID: 624428

Prognosis

Margaryan NV, Gilgur A, Seftor EA, Purnell C, Arva NC, Gosain AK, Hendrix MJ, Strizzi L
Int J Mol Sci 2016 Mar 22;17(3):418. doi: 10.3390/ijms17030418. PMID: 27011171Free PMC Article
Cox NH, Malcolm A, Long ED
Dermatology 1997;194(3):213-6. doi: 10.1159/000246104. PMID: 9187835
Schadendorf D, Haas N, Worm M, Ostmeier H, Kohlmus C, Gottschalk J, Algermissen B, Jautzke G, Czarnetzki BM
Br J Dermatol 1993 Nov;129(5):609-14. doi: 10.1111/j.1365-2133.1993.tb00496.x. PMID: 8251363
Sanal O, Küçükali T, Ersoy F, Tinaztepe K, Göğüş S
Turk J Pediatr 1993 Apr-Jun;35(2):115-9. PMID: 8249191
Eady RA, Gilkes JJ, Jones EW
Br J Dermatol 1977 Sep;97(3):267-78. doi: 10.1111/j.1365-2133.1977.tb15182.x. PMID: 921897

Clinical prediction guides

Margaryan NV, Gilgur A, Seftor EA, Purnell C, Arva NC, Gosain AK, Hendrix MJ, Strizzi L
Int J Mol Sci 2016 Mar 22;17(3):418. doi: 10.3390/ijms17030418. PMID: 27011171Free PMC Article
Motegi S, Yokoyama Y, Ogino S, Yamada K, Uchiyama A, Perera B, Takeuchi Y, Ohnishi H, Ishikawa O
Acta Derm Venereol 2015 Nov;95(8):978-84. doi: 10.2340/00015555-2123. PMID: 25917897
Incerti B, Cortese K, Pizzigoni A, Surace EM, Varani S, Coppola M, Jeffery G, Seeliger M, Jaissle G, Bennett DC, Marigo V, Schiaffino MV, Tacchetti C, Ballabio A
Hum Mol Genet 2000 Nov 22;9(19):2781-8. doi: 10.1093/hmg/9.19.2781. PMID: 11092754
Tobin DJ, Fenton DA, Kendall MD
J Invest Dermatol 1990 Jun;94(6):803-7. doi: 10.1111/1523-1747.ep12874660. PMID: 2355182
Hull MT, Epinette WW
Dermatologica 1984;168(3):112-6. doi: 10.1159/000249680. PMID: 6714502

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