Neutropenia and immunisation

背景

Neutropenia is a condition where a person has a lower than 普通的 number of neutrophils. Neutrophils are a type of white blood cell responsible for fighting bacterial and fungal infections. Neutropenia is an immunocompromising condition that can be acute (temporary) or chronic (long。term)

是 引起的 certain medications or therapies, autoimmune conditions, infections, or other medical conditions.

Neutropenia and vaccines

Due to their lowered immunity, 我ndividuals with

eutropenia are more vulnerable to infection秒 and their complications, meaning protection is a priority. However, protection is complicated since some vaccines are contraindicated due to the risk of vaccine。associated disease. The following guidance refers to the immunisation of individuals with long。term 或者 chronic neutropenia.

建议

灭活疫苗

It is recommended and safe for people with chronic neutropenia to receive inactivated vaccines as per 这 routine National Immunisation Program (NIP) schedule. Given patients with neutropenia are at increased risk of bacterial infections, 额外的 肺炎球菌

Are also recommended. 年度的 我nfluenza vaccination is recommended for those aged 6 months and older.

Live。attenuated viral vaccines

Neutropenia itself is 不是 a contraindication to live‑attenuated viral vaccines, as patients with an isolated neutropenia would be expected to handle viral infections, and correspondingly live‑attenuated viral vaccines, in most circumstances.

In cases of an undefined neutropenia some caution should be exercised, given neutropenia can occur in the setting of conditions which also affect lymphocyte (another type of white blood cell) number and function.

A number of patients with chronic moderate。严重 neutropenia (neutrophil count < 1×10^9/L) will not have a defined molecular defect; the cause may be unclear, or they may have suspected immune neutropenia for which there is no diagnostic test. In these patients, an evaluation for an underlying immune defect is recommended prior to administration of live‑attenuated viral vaccines (e.g. rotavirus, 麻疹死亡率

). If there are no concerning features on history, examination or screening investigations, live‑attenuated viral vaccines are recommended, as per the NIP. If any abnormalities or concerns are raised, a formal immunology consult should be sought prior.

In patients for whom the neutropenia is expected to be transient, or further investigation is planned in the near future (e.g. bone marrow examination or molecular studies), consideration should be given to delaying live‑attenuated viral vaccines until this information is available.

Live‑attenuated viral vaccines are 禁忌 in patients with other inborn errors of immunity, such as leucocyte adhesion disorder, Chediak–Higashi syndrome or other defects in cytolytic granule release.

Live‑attenuated bacterial vaccines

Live‑attenuated bacterial vaccines (for example, the mycobacterial BCG vaccine, oral typhoid (Vivotif) vaccine) are generally 禁忌 in patients with neutropenia, including those with some phagocytic cell defects. This is due to an increased risk of 疫苗。associated adverse events in this group, including delayed healing at the BCG site. When indicated, typhoid protection can be provided by using the alternate inactivated vaccine (Typhim Vi).

If there is a high risk of tuberculosis exposure in an individual with neutropenia, such as travel to a endemic area to visit friends and relatives (VFR), BCG vaccine should be discussed with both an immunisation specialist and haematologist.

资源

• Australian Immunisation Handbook: Phagocytic and neutrophil disorders: recommendations for vaccination
• Australian Immunisation Handbook: Risk conditions for Pneumococcal Disease
• 澳大利亚免疫手册：免疫功能低下者的疫苗接种
• 2013 IDSA Clinical practice guideline for vaccination of the immunocompromised host
• Medical advisory committee of the immune deficiency foundation: Recommendations for live viral and bacterial vaccines in immunodeficient patients and their close contacts 2014
• Canadian Immunisation Guide: Immunization of immunocompromised persons
• Martire B, Azzari C, Badolato R, Canessa C, Cirillo E, Gallo V, et al. Vaccination in immunocompromised host: Recommendations of Italian Primary Immunodeficiency Network Centers (IPINET). Vaccine. 2018;36(24):3541-54