{"id":22813,"date":"2026-04-28T16:39:40","date_gmt":"2026-04-28T06:39:40","guid":{"rendered":"https:\/\/mvec.mcri.edu.au\/?post_type=references&p=22813"},"modified":"2026-04-30T11:17:52","modified_gmt":"2026-04-30T01:17:52","slug":"discoloured-leg-syndrome","status":"publish","type":"references","link":"https:\/\/mvec.mcri.edu.au\/vi\/references\/discoloured-leg-syndrome\/","title":{"rendered":"Discoloured leg syndrome"},"content":{"rendered":"
<\/p>\n

L\u00fd l\u1ecbch<\/strong><\/h2>\n

Discoloured<\/span>\u00a0leg syndrome\u00a0<\/span>(DLS)\u00a0<\/span>is a\u00a0<\/span>rare\u00a0<\/span>phenomenon that\u00a0<\/span>C\u00f3 th\u1ec3\u00a0<\/span>occur<\/span>\u00a0<\/span>after receipt of an injected vaccine<\/span><\/span>.<\/span>\u00a0It<\/span>\u00a0is a transient condition<\/span>\u00a0<\/span>involv<\/span>

<\/div><\/span>\u00a0<\/span><\/span>either\u00a0<\/span><\/span><\/span>an even or patchy\u00a0<\/span>colour<\/span>\u00a0change\u00a0<\/span>to the skin\u00a0<\/span>in the lower\u00a0<\/span>extremities<\/span>\u00a0<\/span>(red,\u00a0<\/span>blue<\/span><\/span>\u00a0or purple)<\/span>\u00a0V\u00e0\u00a0<\/span>may or may not involve p<\/span>etechiae\u00a0<\/span>(<\/span><\/span>pin-point red spots on the\u00a0<\/span><\/span><\/span>skin<\/span><\/span><\/span>)\u00a0<\/span>ho\u1eb7c<\/span>\u00a0swelling<\/span>.<\/span><\/span><\/p>\n

Diagnosis<\/strong><\/h2>\n

DLS\u00a0<\/span>l\u00e0\u00a0<\/span>be diagnosed based on clinical presentation\u00a0(e.g.\u00a0symptom\u00a0profile, onset of\u00a0symptoms<\/span> and\u00a0symptom\u00a0resolution).<\/span><\/p>\n

Unlike\u00a0injection site reactions (ISRs)<\/a><\/span>, DLS does not radiate from the site of injection,\u00a0and\u00a0can\u00a0impact\u00a0<\/span>one<\/span>\u00a0or both<\/span>\u00a0leg<\/span>S<\/span>, even if only one injection has been administered. Discolouration can also extend up to the pelvis.<\/span><\/p>\n

Investigations are\u00a0generally not\u00a0required.\u00a0Despite\u00a0the presence of\u00a0petechiae,\u00a0there is no drop in\u00a0platelet\u00a0count.<\/span><\/p>\n

As DLS involves skin changes and symptoms can occur quickly, it is important to differentiate it from\u00a0anaphylaxis<\/span>, especially if symptoms start within 30 minutes of vaccination.<\/span><\/p>\n

Association and incidence<\/strong><\/h2>\n

DLS is reported at a rate of 58 per 100,000 children vaccinated. Although the median onset time for colour change is approximately 3.5 hours, DLS can be seen quite quickly post-vaccination (within 30 minutes). Where symptoms of petechiae occur, the median onset time is 12 hours following vaccination. Generally, colour change (median duration = approximately 2 hours) does not last as long as petechiae (median duration = 54 hours).<\/p>\n

S\u1ef1 \u0111\u1ed1i \u0111\u00e3i<\/h2>\n

As a precaution, assessment of airway, breathing and circulation is advised.<\/p>\n

Symptoms of DLS are transient and will resolve on their own without treatment.<\/p>\n

Any adverse event following immunisation (AEFI), including DLS, should be reported to the\u202fadverse event reporting service\u202fin your jurisdiction<\/a>. In Victoria, this is SAEFVIC<\/a>.<\/p>\n

H\u00e0m \u00fd cho li\u1ec1u l\u01b0\u1ee3ng trong t\u01b0\u01a1ng lai<\/strong><\/h2>\n

Recurrence\u00a0<\/span>of DLS\u00a0<\/span><\/span>l\u00e0\u00a0<\/span><\/span><\/span>uncommon, but<\/span><\/span><\/span>\u00a0<\/span><\/span><\/span>can occur<\/span><\/span>.<\/span><\/span><\/span>\u00a0<\/span><\/span>h<\/span><\/span><\/span>owever<\/span><\/span>, DLS<\/span><\/span><\/span>\u00a0l\u00e0\u00a0<\/span>not a contraindication to<\/span>\u00a0receiving<\/span>\u00a0future vaccin<\/span>es<\/span>. Given that DLS appears to be age-related, families can be reassured that children are l<\/span>ess likely to experience sym<\/span>p<\/span>toms as they get older.<\/span><\/span><\/p>\n<\/div>

<\/p>\n

T\u00e0i li\u1ec7u<\/h2>\n