Untersuchungen zu Aquaporin 1 und Aquaporin 4 im Liquor von Patienten mit bakterieller und viraler Meningitis im Vergleich zu einer Kontrollgruppe

Abstract

Background: The bacterial meningitis has a lethality of 10-20%. A brain edema was developed by 14% of the patients with bacterial meningitis. Current research is looking into the importance of aquaporines for the development and resorption of brain edema, especially the cytotoxic and vasogenic brain edema. The aim of this study was to find out whether there are aquaporin 1 and 4 measurable in cerebrospinal fluid (and serum) of patients with bacterial or viral meningitis, compared to a healthy control group. Additionally we wanted to find out, if the measurement of aquaporines in the cerebrospinal fluid can be used to differentiate between bacterial and viral meningitis or if it can be used to give a prognosis on the dimensions of a brain edema or on the outcome of the patients with bacterial or viral meningitis. Method: Aquaporin 1 and 4 were measured in the cerebrospinal fluid (and serum) of patients with bacterial (nCSF = 35 , nserum = 20) and viral (nCSF = 22) meningitis as well as in a control group (nCSF = 27 , nserum = 12) using a (commercial) ELISA. Routinely taken clinical data and laboratory findings were compared and set into correlation with the aquaporin-concentrations. A subgroup of patients with bacterial meningitis (n = 8) underwent neuropsychological testing. Results: Aquaporin 1 and aquaporin 4 were detected in all three groups in the cerebrospinal fluid (and serum). In about 40% of the tests the concentration of aquaporin 4 could not be measured. There was a significant difference in the Kruskall-Wallis-test for aquaporin 1 (p = 0,0001) and aquaporin 4 (p = 0,035) in the cerebrospinal fluid comparing all three groups. In the group of patients with bacterial meningitis we found a negative correlation between aquaporin 1 and 4 in the cerebrospinal fluid (r = - 0,519, p = 0,002). There were no relevant correlations of clinical data, laboratory findings or the results of the neuropsychological testing with the aquaporin 1 or aquaporin 4 concentration. Conclusion: This work could for the first time proof that aquaporin 1 and aquaporin 4 are detectable in the cerebrospinal fluid (and serum) of patients with bacterial and viral meningitis as well as in a healthy control group. There was a significant difference in the concentration of aquaporin 1 and aquaporin 4 in the cerebrospinal fluid in the Kruskal-Wallis-test comparing all three groups. We were not able to draw any conclusion regarding the differentiation between viral and bacterial meningitis, the dimension of the brain edema or the prognosis using the aquaporin concentrations. Concerning the origin of the measured aquaporins, no final conclusion can be drawn. More basic research needs to be done here.