IgM clearance/Albumin clearance [Ratio] in Serum and CSF

IgM/Alb clear Ser+CSF-Rto

Definition

CSF IgM, IgA, and IgG indexes are indicators of intrathecal immunoglobulin synthesis. The calculations incorporate the CSF-serum albumin quotient, an indicator of blood-brain-barrier (BBB) function, in order to differentiate whether the immunoglobulins found in the CSF were produced intrathecally or leaked across the BBB. These immunoglobulin indexes can be useful in the diagnosis of central nervous system infections, neoplasms and primary neurologic diseases such as multiple sclerosis. They also have the potential to monitor treatment efficacy in conditions such as systemic lupus erythematosus with CNS involvement, in which one study found that all three indexes decreased significantly along with CNS symptoms during successful treatment. The CSF IgM index is calculated as (CSF IgM/serum IgM)/(CSF albumin/serum albumin), which can also be represented as (CSF IgM x serum albumin)/(serum IgM x CSF albumin). [PMID: 3899036]

Alb; Alb clear; Both serum and cerebrospinal fluid; Cerebral spinal fluid; Cerebrospinal Fl; Chemistry; Cl; Clear; Clearanc; Clearances; Clr; Immune globulin M; Immunoglobulin M; Point in time; Protein.albumin; QNT; Quan; Quant; Quantitative; Random; Ratios; Rto; Serum; Spinal Fl; Spinal Fld; Spinal Flu; Spinal Fluid; SR