I'm sorry I don't know about IgM but I think your doctor should be able to give you a simple explanation, enough to allay your concerns anyway.
A test result only has signifcance when viewed along with other test results and symptoms. This IgM seems to be often associated with infectious diseases so maybe your levels are high because of some recent infection but this is just me speculating
APS is a blood clotting condition and everybody with a lupus diagnosis should be tested for it if they were not already as part of the diagnostic testing.
APS stands for anti phospholipid syndrome.
The two main tests are for anticardiolipin antibodies, and then clotting tests for something called "lupus anticoagulant". The name was given because this was first identified in lupus patients but in fact more people have this abnormality without having lupus. There are some other tests that help determine if the high levels are due to autoimmune disease or infectious diseases which can give false positives, for lupus. About one third of people with lupus have the antibodies and about one third suffer from the strokes or thrombosis or repeated miscarriages that would lead to a diagnosis of APS, or so I have read.
If you have not suffered such symptoms you technically do not get an APS diagnosis, however there can be many other associated symptoms, such as headaches and cognitive problems.
The presence of the antibodies can also count towards a lupus diagnosis, see ACR Criteria.
Levels can be raised from time to time for other reasons, or either might be negative or not significantly high so usually both tests are run at an interval of at least six weeks.
Treatment is with blood thinners when there have been major associated incidents but aspirin is often given to try to thin the blood a bit in the hope of avoiding major problems occuring. Plaquenil has a role to play too as it slightly thins the blood and can often help with some of the associated symptoms. Many of us are on low dose aspirin ( about 75mgs a day) for several other reasons such as the very high risk of cardiac and artery disease in women with lupus. Any pain killing effects of the aspirin are incidental because there are much better ways of dealing with pain. At such a low dose I shouldn't think it would make that much difference to the sort of chronic joint pain suffered in lupus.
Cheers
Clare
