Thrombosis with thrombocytopenia syndrome

Thrombosis with thrombocytopenia syndrome (TTS), also known as Vaccine-induced prothrombotic immune thrombocytopenia (VIPIT), is a rare and new syndrome which has been reported in people who have received COVID-19 AstraZeneca vaccination. The syndrome is characterised by thrombosis (such as central venous sinus thrombosis (CVST) or splanchnic thrombosis), thrombocytopenia and confirmed with a positive PF4-heparin ELISA.

There have been a number of reports of this worldwide, including in the UK, Germany, Scandinavia and Australia. There appears to be a causal link between administration of COVID-19 AstraZeneca and this syndrome.

How does COVID-19 AstraZeneca trigger TTS/VIPIT?

There is currently no exact mechanism identified to describe how COVID-19 AstraZeneca may trigger TTS/VIPIT. There is some indication that this is an immune-mediated process. In certain cases, anti-platelet factor 4 (anti-PF4 antibodies) have been found.

TTS/VIPIT appears similar to an autoimmune condition known as heparin induced thrombocytopenia (HIT), where an immune reaction to heparin used for anticoagulation impacts platelet function.

What is the risk of TTS/VIPIT?

The estimated risk of TTS/VIPIT is approximately 1 in 250,000 persons following administration of COVID-19 AstraZeneca. Current information suggests that TTS/VIPIT is more frequently reported following receipt of dose 1.

Is there a risk of developing other clotting disorders after receiving COVID-19 AstraZeneca?

There is no evidence that COVID-19 AstraZeneca increases the overall risk of thrombosis or clotting (eg. other clotting disorders such as deep vein thromboses, pulmonary emboli, myocardial infarction, stroke) beyond the baseline rate in the general population.

Who is at risk of TTS/VIPIT?

Evidence thus far indicates there to be a higher risk of TTS/VIPIT in the younger population (< 50 years old), although there has been a small number of cases identified in older adults. There is some evidence to suggest that the incidence is higher in women compared to men, although this may be because more vaccine doses have been given to women in vaccine rollouts worldwide thus far.

There is currently no evidence or biological risk factors that have been identified that either increase or decrease your risk of TTS/VIPIT.

Currently, ATAGI recommends that anyone with a history of either central venous sinus thrombosis (CVST) or HIT should defer vaccination with any COVID-19 vaccine as a precautionary measure.

TTS/VIPIT can cause serious long-term disability or death (with death occurring in approximately 25% of reported cases).

What are the potential very rare symptoms indicating TTS/VIPIT?

The features of TTS/VIPIT occur in days 4-20 after vaccination.

They may include symptoms of blood clots in various organs including (but not limited to):

  • Severe headaches unresponsive to simple analgesia
  • Abdominal pain
  • Significant respiratory symptoms/distress
  • Visual changes
  • Vomiting
  • Seizures
  • Focal neurological deficits/changes
  • Confusion/encephalopathy

NB: These symptoms are different from the common or expected side effects following vaccination which usually occur in the first 24-48 hours and last 1-2 days.

What types of investigations should be considered if there is a suspicion of TTS/VIPIT?

If TTS/VIPIT is suspected, there may be an investigation of platelet levels, clotting factors and special immunological and antibody tests, as well as imaging studies to determine the site and size of any potential thrombosis/clots. If warranted, decisions for specific treatments for this condition are to be made in consultation with a specialist haematologist and may include anticoagulation with a non-heparin anticoagulant and/or IVIG.

For more information please refer to THANZ advisory statement, April 1 2021: Suspected Vaccine Induced Prothrombotic Immune Thrombocytopenia (VIPIT) or Updated ATAGI statement for healthcare providers on a specific clotting condition being reported after COVID-19 vaccination.

Resources

Authors: Daryl Cheng (Paediatricican, Royal Children's Hospital), Francesca Machingaifa (MVEC Education Nurse Coordinator), Davina Buntsma (MVEC Immunisation Fellow) and Rachael McGuire (MVEC Education Nurse Coordinator)

Date: April 2021

Materials in this section are updated as new information and vaccines become available. The Melbourne Vaccine Education Centre (MVEC) staff regularly reviews materials for accuracy.

You should not consider the information in this site to be specific, professional medical advice for your personal health or for your family’s personal health. For medical concerns, including decisions about vaccinations, medications and other treatments, you should always consult a healthcare professional.

 

 

 

 

 

 

 

 

 

 

 


Tetanus prone wounds management

What is tetanus?

Tetanus is a bacterial infection caused by the bacteria Clostridium Tetani. It commonly lives in dirt, dust and animal waste and the spores are usually introduced into the body via lacerations or puncture wounds. The spores can survive in a wound for as long as 3 months before becoming active. The most common time frame for presentation of tetanus is around 14 days, but it can also be delayed (up to months), after the injury. Unlike other vaccine preventable diseases, tetanus is not transmissible from person to person.

Examples of wounds that are considered tetanus prone-

  • Bites, either animal or human
  • Deep penetrating wounds
  • Wounds with foreign bodies i.e. splinters
  • Burns
  • Open fractures
  • Cuts or lacerations with outdoor equipment
  • Tooth reimplantation post avulsion
  • IV drug use sites

Tetanus can occur following trivial or even unnoticed wounds. Tetanus prophylaxis should be strongly considered for all unimmunised or partially immunised persons, regardless of the nature of the wound.

Signs and Symptoms

People infected with tetanus commonly show signs of muscle spasm, mainly around the face and neck, including lock jaw. Spasms can last for significant amounts of time, requiring large amounts of analgesia.

Severe cases can lead to breathing difficulties, respiratory infections and heart attack. 1 in 10 people with tetanus will die despite receiving prompt medical treatment.

Prevention

Vaccination is the most effective way to prevent tetanus.

As per the National Immunisation Program (NIP), a primary course of tetanus vaccination is given at 6-weeks, 4-months, and 6-months of age (Infanrix hexa®).

Boosters are then scheduled at-

  • 18-months (Infanrix®/Tripacel®)
  • 4-years (Infanrix-IPV®/Quadracel®)
  • Year 7 (high school program)/12 to 13-years of age (Boostrix®)

A further booster dose as dTpa (Boostrix®/Adacel®) is recommended but not funded, for adults aged ≥ 50-years who have not received a dose of tetanus-containing vaccine in the last 10 years.

Regular booster doses every 10-years are no longer recommended. However immunisation advice regarding the management of a tetanus prone wound varies from this [see below].

Tetanus prone wounds

The correct management of a tetanus prone wound is vital in the prevention of tetanus [see resources: RCH Clinical Practice Guideline].

Key messages include:

  • Where applicable, wounds should be cleaned, disinfected, and surgically treated if required
  • In paediatric patients, a full immunisation history should be taken, ensuring that a primary course of tetanus vaccination has been completed
  • If a patient is > 5 years post a tetanus vaccine, then a booster is recommended
  • An important age group to consider for a booster are those aged between 9-13 yrs, as they are 5-years post their 4-year old vaccine, and may not have yet received their Year 7 (adolescent) booster

Children or adults who are unimmunised or only partially

Every person will receive an injury at some point in their life. Whether it is tetanus prone, will depend on medical assessment. Even the most superficial wounds could be at risk of tetanus depending on the mechanism of injury. 

An unimmunised or partially immunised person is at greatest risk of contracting tetanus. The elderly population are often included in this group due to timing of their last booster, most commonly being exposed whilst gardening.

A partially immunised person is one who has not yet completed a primary course, or has received < 3 doses of a tetanus containing vaccine. These people require not only a tetanus-containing vaccine but also tetanus immunoglobulin (TIG) [refer to resources for specific advice].

If immunisation history is in doubt, TIG and a tetanus-containing vaccine should be administered.

Immunoglobulin provides protection for up to 1 month after administration. Vaccination provides protection against the toxin and not the bacteria. A full course of 3 doses of a tetanus-containing vaccine should be completed to ensure ongoing immunity. If individual advice is required consider a referral to a Specialist Immunisation Clinic.

ADT® vaccine

The use of ADT® in children aged < 10-years is not recommended as it does not contain enough antigen to promote an adequate immune response in the unimmunised, however there are unlikely to be safety issues. Parents requesting this option should be made aware of the increased risk of contracting tetanus.

Management of immunosuppressed patients with a tetanus prone-wound

Immunosuppressive medications are becoming more common place in the management of particular medical conditions. Patients who may be immunosuppressed include:

  • Autoimmune conditions ie: IBD, lupus, rheumatologocial conditions
  • Solid organ transplant recipients, Haematopoietic stem cell transplant recipients
  • All oncology patients

Patients who are immunosuppressed should be considered unimmunised and treated accordingly with immunoglobulin and a vaccine.

Resources

Author: Lynne Addlem (Immunisation Nurse, The Royal Children’s Hospital) and Rachael McGuire (Education Nurse Coordinator)

Reviewed by: Lynne Addlem (Immunisation Nurse, The Royal Children’s Hospital)

Date: September 2020

Materials in this section are updated as new information becomes available. The Melbourne Vaccine Education Centre (MVEC) staff regularly review materials for accuracy.

You should not consider the information in this site to be specific, professional medical advice for your personal health or for your family’s personal health. For medical concerns, including decisions about vaccinations, medications and other treatments, you should always consult a healthcare professional.


Travel medicine

Travel medicine is a rapidly expanding discipline as more people (including children and adolescents) go on overseas trips, including visiting friends and relatives (VFRs).

Travel medicine includes general advice to minimise the risk of injury and infections, which will vary depending on the location of travel, duration and time of year.

The traveller may be at increased risk of vaccine preventable diseases. To help determine which routine and additional special travel vaccines may be required, there are a number of excellent websites, with country specific updates and information on emerging infections. For specific pre-travel advice this is best done 4-6 weeks prior to departure, to allow time for the vaccines to start to work before arriving at your overseas destination.

Resources

The RCH travel health resources

MVEC travel related resources

Yellow Fever vaccination centres

The CDC in the United States

Other resources

Authors: Nigel Crawford (Director SAEFVIC, Murdoch Children’s Research Institute) and Rachael McGuire (SAEFVIC Research Nurse, Murdoch Children’s Research Institute)

Reviewed by: Rachael McGuire (SAEFVIC Research Nurse, Murdoch Children's Research Institute)

Date: December 2020

Materials in this section are updated as new information and vaccines become available. The Melbourne Vaccine Education Centre (MVEC) staff regularly reviews materials for accuracy.

You should not consider the information in this site to be specific, professional medical advice for your personal health or for your family's personal health. For medical concerns, including decisions about vaccinations, medications and other treatments, you should always consult a healthcare professional.