BIOCHEMICAL MARKERS IN TUBERCULOSIS MENINGITIS

In the search for finding biochemical markers in patients with tubercu losis meningitis (TBM), amino acids, nitrite (metabolite of nitric oxi de), vitamin B12, homocysteine along with catecholeamines and their me tabolites are quantitated in cerebrospinal fluid. Among the amino acid s, aspartic acid (ASP) and glutamic acid (GLU) both excitatory amino a cid, GABA, glycine (GLY),phenylalanine (PHE),tryptophan (TRP) were all significantly increased where as taurine (TAU) is significantly decre ased in TBM patients. The levels of nitrite and its precursor arginine (ARG) were significantly higher in TBM patients and are linearly rela ted. There is also a positive correlation between GLU and ARG and nitr ite indicating that GLU, ARG and nitrite are interrelated and contribu te simultaneously to the neuronal death in TBM. Among the catecholamin es, noradrenaline (NA) and its metabolite 3-methoxy 4-hydroxyphenylgly col (MHPG) are significantly increased where as unchanged levels of do pamine (DA) and its metabolite homovalinic acid (HVA), and increased l evel of 3,4-dihydroxy phenylacetic acid (DOPAC) were observed. Among t he indoleamines, 5-hydroxy 3-indoleacetic acid (5-HIAA) is unchanged w here as serotonin (5-HT) level is significantly increased. A significa nt increased. level of CSF homocysteine (HC) and a decreased level of vitamin B12 was found in TBM patients. This indicates that TBM patient s are particularly prone to vitamin B12 deficiency resulting into incr ease level of HC. This study shows the importance of these biological markers which could be used in designing the therapy and confirming th e diagnosis of these patients.