A 54 year old woman presented with symptoms resulting from a
thrombosis of the lateral transverse and sagittal sinuses the day after an infusion of
intravenous immunoglobulin (
IVIg) replacement treatment. She had previously suffered a milder episode after
IVIg. Following recurrent bacterial chest
infections and
sinusitis for more than 40 years, a diagnosis of
IgG1 deficiency had been made two years earlier, after exclusion of other causes. She made a good recovery from the
thrombosis but high platelet counts were investigated and primary thrombocythaemia was diagnosed. Investigation of humoral immunity revealed protective amounts of
IgG antibodies to pathogens, and because the previous
IgG1 deficiency had resolved
IVIg infusions were not restarted. She made a good response to treatment with
hydroxyurea, with improvement of the
headaches and lowering of the platelet counts. Prophylactic
antibiotics reduced the number of bacterial chest
infections and nasal
corticosteroids improved the chronic
sinusitis. This case is presented to highlight the need to look for other contributing factors for severe recurrent
headaches after
IVIg treatment, and to consider the risk of
thrombosis even when replacement doses of
IVIg are used. It is also important to emphasise the need to ensure that an isolated
IgG subclass deficiency is not transient; that failure to produce specific
IgG antibodies to immunisation and/or exposure
antigens is confirmed, thus meeting the criteria for the diagnosis of
primary antibody deficiency. A thorough risk-benefit assessment is essential before blood product treatment is started.