HLA - B5 Test

HLA (human leukocyte antigen) B5 has two splits B•51 and B•52 of which only B•51 is important in the etiology of Behcet's disease (Behçet's disease is an inflammation of the wall of blood vessels that can involve the eyes, skin, and the rest of the body.). It is most prevalent in the Middle East and the Far East. HLA B• 51 and B•52 have almost similar distribution in Indian population ranging from 6.8- 15% in various ethnic groups in the country. Ocular involvement, which could lead to serious complications, is a very important feature of Behcets disease. HLA- B •51 positivity increases the risk for Behcet's disease by six times. HLA B•52 is not associated with additional risk.

No special preparations required. Inform your doctor about your past medications, if any. Keep the reports handy. It is advisable that you should either wear a sleeve-less or a half-sleeve shirt or wearing a shirt with full- sleeves that can easily be rolled-up till elbow so that the doctor can take a blood sample easily.

Homozygotes of B51 shows considerably high risk for disease indicating a possible gene-dose effect. B51 is capable of distinguishing several varieties of disease. HLA B5 would be a negative factor in visual prognosis in Behçet's disease. patients presenting with frequent ocular attacks had significantly higher HLA B5 positivity than the patients with rare attacks.

Blood for an HLA test is drawn in the same way as standard blood tests, the HLA blood sample is usually forwarded to a specialized lab for processing. Sample required: A blood sample drawn from a vein in your arm; sometimes, for HLA typing, a swab from the inside of the cheek (buccal swab) An alcohol pad is used to clean the skin. AA needle is then injected through the part of rinsed skin into to your vein or heel; specifically in the one that can be seen from the skin. The blood is dragged out from the needle by a nozzle. Then, it’s collected in a vessel with the relative label on it. (Put some ice on the injected part if you feel any irritation and find any bruises or rashes there.)