Visual problems may also be the result of papilledema (swelling of the optic disc) due to obstruction by granulomas of the normal cerebrospinal fluid (CSF) circulation.Seizures (mostly of the tonic-clonic/"grand mal" type) are present in about 15 percent and may be the presenting phenomenon in 10 percent.Meningitis (inflammation of the lining of the brain) occurs in 3–26 percent of cases. Symptoms may include headache and nuchal rigidity (being unable to bend the head forward). It may be acute or chronic.Accumulation of granulomas in particular areas of the brain can lead to abnormalities in the function of that area. For instance, involvement of the internal capsule would lead to weakness in one or two limbs on one side of the body. If the granulomas are large, they can exert a mass effect and cause headache and increase the risk of seizures. Obstruction of the flow of cerebrospinal fluid, too, can cause headaches, visual symptoms (as mentioned above) and other features of raised intracranial pressure and hydrocephalus.Involvement of the spinal cord is rare, but can lead to abnormal sensation or weakness in one or more limbs, or cauda equina symptoms (incontinence to urine or stool, decreased sensation in the buttocks). Endocrine
Granulomas in the pituitary gland, which produces numerous hormones, is rare but leads to any of the symptoms of hypopituitarism: amenorrhoea (cessation of the menstrual cycle), diabetes insipidus (dehydration due to inability to concentrate the urine), hypothyroidism (decreased activity of the thyroid) or hypocortisolism (deficiency of cortisol).
Patients are treated similarly to patients suffering the counterparts those with multiple myeloma except that the focus is treating or preventing kidney damage using chemotherapy to reduce production of the monoclonal light chain and thereby stopping, reversing, or preventing kidney injury. Plasma cell leukemia
Plasma cell leukemia is a form of multiple myeloma in which significant numbers of typically immature appearing plasma cells, i.e. plasmablasts, circulate in the blood. Very small numbers of plasma cells may reach the circulation in non-IgM multiple myeloma, non-IgM SMM, and, exceptionally, non-IgM MGUS. In these plasma cell dyscrasias, the presence of even very small numbers of circulating plasma cells is a poor prognostic indicator. In plasma cell leukemia, however, circulating plasma cells reach far higher numbers and at these circulating levels are associated with exceptionally poor  survival rates. The International Myeloma Working Group has defined the diagnostic criteria for plasma cell leukemia as the presence in blood of >2x109 plasma cells per liter or, alternatively, >20% of nucleated blood cells being plasma cells. More recently, the Group has suggested that values of 0.5x109 or 5%, respectively, may be more appropriate from a therapeutic viewpoint and therefore should be studied as a definitive criterion for the disease. A recent study supported this suggestion in finding that multiple myeloma patients with >5% circulating plasma cells had a prognosis much worse than that for multiple myeloma and similar to that for plasma cell leukemia. Flow cytometry immunophenotyping of blood cells to detect clonal phenotypes of plasma cells seen in multiple myeloma (e.g.