When I was first diagnosed with thyroid cancer, I didn't feel any odd lumps or nodules in my neck, but I was suffering from muscle weakness, tiredness and getting constant colds. After a particularly nasty bug I noticed that my lymph nodes never seemed to go down in size.
SIRS is nonspecific and can be caused by ischemia, inflammation, trauma, infection, or several insults combined. Thus, SIRS is not always related to infection. Venn diagram showing overlap of infection, bacteremia, sepsis, systemic inflammatory response syndrome (SIRS), and multiorgan dysfunction.
The causes of PMS are not clear, but several factors may be involved. Changes in hormones during the menstrual cycle seem to be an important cause. These changing hormone levels may affect some women more than others. Chemical changes in the brain may also be involved.