Author: Dr Diana Purvis, Paediatric Dermatologist, Starship Hospital, Auckland, New Zealand. Reviewed by Gary Reynolds PhD (Immunology) FRNZCGP, GP Medical Advisor to IMAC, April 2012.
Immunodeficiency is defined as inadequate functioning of the immune system. Immunodeficiency can be caused by inherited syndromes, infections, drugs, medical conditions, pregnancy, ageing and many other factors. It can occur at multiple points across the immune response. It can then lead to:
Immunodeficient people that become unwell should be carefully evaluated and infection should be treated aggressively.
Immunosuppression is a general dampening of the immune response, usually in response to immunosuppressive drugs. The immune response is still mounted but it is not as efficient or efficacious.
Immunosuppressive drugs include:
Lower doses or shorter courses of systemic steroids are not considered significantly immunosuppressive. Low-dose methotrexate used for skin diseases mainly acts as an anti-inflammatory drug and is only weakly immunosuppressive.
It is essential that people with immunodeficiency are adequately immunised against vaccine-preventable diseases.
Effective immunisation can be due to natural infection or vaccination. Prior to starting immunosuppressive therapy, determine the following:
The government-funded New Zealand National Immunisation Schedule (2018) includes the following vaccines:
Vaccines recommended for travel may include hepatitis A, cholera and yellow fever (unfunded).
Live injected vaccines are MMR, oral polio (not IPV), varicella, zoster (shingles), yellow fever and BCG. There are live oral vaccines for rotavirus and typhoid and live nasal vaccine for influenza. These are best avoided while on immunosuppressive medication because they may result in severe vaccine reactions.
Check varicella, measles, hepatitis A/B/C and HIV serology. (There are no vaccines for hepatitis C or HIV).
To avoid the risks of preventable infections:
*New Zealand Immunisation Schedule 1 April 2018
All patients on immunosuppressants should be warned that they are at risk of more severe infections than usual. They should be told to alert their care team if they are exposed to chickenpox (varicella) or measles.
Passive antibody protection is not considered necessary for those who have evidence of immunity with detectable IgG antibodies and are taking methotrexate as their only immunosuppressive drug.
There is a significant risk of varicella if a non-immune person is exposed to the virus during the infectious period. This occurs from 2 days before the rash appears until the blisters have crusted over. The incubation period after exposure is 7-21 days. ‘Significant’ exposure is considered to be 15 minutes of close contact/play with a contagious individual.
Chickenpox may also occur after direct contact with shingles/herpes zoster blisters.
If an immune suppressed patient is in contact with varicella, passive protection should be provided with varicella zoster immune globulin (VZIG) within 96 hours (ideally 72 hours) of contact.
There is a significant risk of measles if a non-immune person is exposed to the virus during the infectious period. This occurs from 5 days before the rash appears until 4 days after the onset of rash. The incubation period for measles is 10-14 days after exposure. ‘Significant’ exposure is considered to be 15 minutes of close contact/play with a contagious individual. Measles in the contact should be confirmed by viral serology, as measles rash may appear similar to other viral exanthems or morbilliform drug eruptions.
If an immune suppressed patient is in contact with measles, the following treatment is recommended regardless of antibody status.
Zostavax Vaccine for Shingles — Do Not Use in Immunocompromised Patients. Medsafe Prescriber Update 38(3): 41-42 September 2017.
See the DermNet NZ bookstore.
© 2019 DermNet New Zealand Trust.
DermNet NZ does not provide an online consultation service. If you have any concerns with your skin or its treatment, see a dermatologist for advice.