Introduction Indications Dermatological indications IVIG in dermatomyositis Administration Duration of effects Risk of infection Precautions Contraindications Side-effects Skin side-effects Skin reaction causes IVIG re-exposure following a skin reaction
Intravenous immunoglobulin (IVIG) is a blood product derived from the pooled plasma of about 10,000 to 20,000 individuals. It is highly purified from plasma by cold alcohol fractionation. Most of the immunoglobulins in IVIG are of the subtype IgG, but there are small and variable amounts of IgA.
IVIG is used to prevent or reduce the severity of infections in persons with immunodeficiency. It provides the body with antibodies to protect against bacteria and viruses. Also, IVIG can also neutralise autoantibodies (antibodies directed against one's self) and hence can be used to treat a variety of autoimmune disorders.
It is approved by the US Food and Drug Administration (FDA) for the treatment of 8 conditions.
The first four conditions account for 70% of IVIG use [1].
However, given the broad action of IVIG, it can also be used off-label to treat a variety of other conditions. The majority of the disorders listed in the table below have documented the efficacy of IVIG in small numbers of patients in uncontrolled studies.
Primary immunodeficiency states |
Secondary Immunodeficiency states |
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Haematologic disorders |
Renal and vasculitic disorders |
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Neuromuscular disorders |
Sensitisation to HLA antigens before transplantation |
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Respiratory disorders |
Skin diseases |
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The use of IVIG in these and other conditions require further assessment using randomised double-blind placebo-controlled trials.
Dermatological conditions account for a small proportion of the total use of IVIG, but it is a rapidly growing indication for its use. Although IVIG has been used to treat several dermatological diseases, it must be noted that its effectiveness has only been shown through the treatment of small and mostly uncontrolled study groups. The exception is the use of IVIG in treating dermatomyositis, where several clinical studies, including a randomised double-blind placebo-controlled trial, have been performed.
The use of IVIG in these and other skin conditions requires further assessment using randomised double-blind placebo-controlled trials.
The mainstay of dermatomyositis treatment usually involves oral corticosteroids alone or in combination with an immunosuppressive agent such as methotrexate, azathioprine, cyclophosphamide and ciclosporin. These medicines all have significant side effects, and often a less than adequate response is achieved with this conventional therapy.
IVIG is a useful additional therapy for patients with dermatomyositis who fail to respond to conventional treatment or who experience unacceptable side effects. A dose of 1-2 g/kg per month administered over two days or 5 days of each month is recommended (currently there is no apparent difference in efficacy between the 2-day and 5-day regimen). A summary of clinical trials shows an overall response rate of 80% at about two months, with a maximal response at four months. Most patients require ongoing IVIG therapy in conjunction with conventional treatments given at lower and better-tolerated dosages.
With the treatment of other skin conditions, IVIG should also be used as an additional therapy. A review of all reported cases of IVIG use in dermatological diseases showed efficacy to be much more significant when IVIG is used as a complementary therapy, with a response rate of 88% compared with 46% if used alone.3
IVIG is given as an infusion into a vein over some time, usually from 2 to 24 hours. The frequency that it is given depends on the underlying condition and varies from once a day to once every 3 to 4 weeks. The dose is typically a total of 2 g/kg body weight delivered over 2 to 5 days.
The duration of the response from IVIG depends on the individual's metabolism and the disease state. On average, the effects of IVIG can last up to a month after each administration.
The pool of donors is carefully screened to eliminate anyone with abnormal liver function or exposure to viral hepatitis or HIV infection. The process of obtaining IVIG in itself removes viruses and bacteria from the plasma. Therefore, IVIG should not pose any risk of hepatitis C, hepatitis B or HIV transmission. Since the introduction of newer techniques of obtaining IVIG in 1987, there have been no cases of transmission of these viruses.
Although immunoglobulins are antibodies from human plasma, individuals with certain conditions need to use this medication with caution. The following medical conditions warrant discussion with your doctor:
IVIG should be avoided by:
Side effects of IVIG therapy are generally mild and self-limiting. The most common side effects occur 30–60 minutes after the onset of the infusion and include:
These symptoms can be managed by stopping the infusion, or a patient can be premedicated with antihistamines and intravenous hydrocortisone.
Other rare side effects include:
Skin reactions to IVIG are uncommon, and the exact incidence is unknown. Of all the reported rashes, a blistering type of eczema is the most common (a type of dermatitis) [2]. It often begins at about 8 to 10 days after exposure to IVIG. The rash characteristically starts as dyshidrotic eczema (pompholyx) with small itchy blisters on the palms, but this may be followed by a more generalised eczematous eruption that spreads throughout the body. The affected individual may become erythrodermic (red all over) and pruritic (itchy).
The skin lesions often resolve within a period of 1 to 4 weeks. The use of topical steroids or systemic steroids controls symptoms and may speed recovery.
Other skin reactions include:
The exact cause of skin reactions to IVIG is unknown. It is thought that the body's immune system reacts to one or several substances within IVIG, such as a stabilising agent, a part of the immunoglobulin, or T cells. The reaction may differ depending on the batch and type of IVIG as the immunoglobulin is obtained from a different pool of individuals.
When an individual develops a skin reaction to IVIG, a second exposure may cause the rash to appear earlier (generally around 8–10 days after infusion) and become more extensive. The immune system has developed memory T cells, and subsequent responses are faster and more severe. Switching the type of IVIG may cause a less severe reaction.
Approved datasheets are the official source of information for medicines, including approved uses, doses, and safety information. Check the individual datasheet in your country for information about medicines.
We suggest you refer to your national drug approval agency such as the Australian Therapeutic Goods Administration (TGA), US Food and Drug Administration (FDA), UK Medicines and Healthcare products regulatory agency (MHRA) / emc, and NZ Medsafe, or a national or state-approved formulary eg, the New Zealand Formulary (NZF) and New Zealand Formulary for Children (NZFC) and the British National Formulary (BNF) and British National Formulary for Children (BNFC).
