Background: West Nile virus neuroinvasive disease (WNND) occurs in less than 1% of infected people. Leukocytosis with lymphocytopenia, mild anaemia, thrombocytopenia, elevated liver and muscle enzymes and hyponatremia are occasionally present in patients with WNND. Cerebrospinal fluid (CSF) findings resemble other viral neuroinfections. The purpose of this study is to pre sent some of the most important laboratory findings of our patients with WNND and to evaluate their correlation with fatal outcome.
Methods: The study included 161 patients with WNND. Their blood and CSF samples were cytobiochemically analysed and the obtained variables were then tested for predictive significance of the disease outcome, or used for differentiation between two clinical syndromes (encephalitis vs meningitis).
Results: West Nile encephalitis was present in 127 (78.9%) patients and West Nile meningitis was diagnosed in 34 (21.1%) cases. Leukocytosis was found in 45.9% patients. CRP level higher than 100 mg/L was registered only in those with encephalitis (p=0.020). CSF leukocyte count was 146±171 per microlitre, with slight lymphocytic predominance (mean 52%). Hypoglycorrhachia was registered in 9.3% of our patients with WNND. Twenty-eight (17.4%) patients died and all of them had encephalitis. Independent predictors of fatal outcome in WNND were serum CRP > 100 mg/L (p=0.011) and CSF proteins > 1 g/L (p=0.002).
Conclusions: WNND usually affects older males. Prolonged neutrophilic predominance in CSF can occasionally be present, as well as hypoglycorrhachia. Patients with encephalitis, high serum CRP and high CSF protein level have a higher risk of fatal outcome.
Uvod: Do neuroinvazivnog oblika groznice Zapadnog Nila (WNND) dolazi kod manje od 1% zaraženih osoba. Kod bolesnika sa WNND se mogu registrovati leukocitoza sa limfocitopenijom, laka anemija, trombocitopenija, povišene vrednosti enzima jetre i mišića i hiponatrijemija. Nalaz u cerebrospinalnoj tečnosti (CST) sličan je kao kod drugih virusnih neuroinfekcija. Cilj rada je prikaz laboratorijskih parametara kod naših bolesnika sa WNND i određivanje njihove korelacije sa smrtnim ishodom.
Metode: U studiju je uključen 161 bolesnik sa WNND. Uzorci njihove krvi i CST su citobiohemijski analizirani i potom je testiran prediktivni značaj dobijenih varijabli na ishod bolesti ili značajnost razlike u zavisnosti od kliničkog sindroma (meningitis ili encefalitis).
Rezultati: West Nile encefalitis je dijagnostikovan kod 127 (78,9%) bolesnika, a West Nile meningitis kod 34 (21,1%) bolesnika. Kod 45,9% bolesnika je registrovana leukocitoza. Vrednosti CRP-a veće od 100 mg/L su zabeležene samo kod bolesnika sa encefalitisom (p=0,020). Zabeleženo je prosečno 146±171 leukocita po mikrolitru CST, sa lakom predominacijom limfocita (prosečno 52%). Hipoglikorahija je registrovana kod 9,3% bolesnika. Umrlo je 28 (17,4%) bolesnika, svi sa encefalitisom. Vrednosti serumskog CRP-a > 100 mg/L (p=0,011) i vrednosti proteina u CST > 1 g/L (p=0,002) bile su nezavisni prediktori smrtnog ishoda kod bolesnika sa WNND.
Zaključak: Od WNND najčešće obolevaju stariji muškarci. Prolongirana predominacija neutrofila u CST i hipoglikorahija se mogu povremeno registrovati. Rizik od smrtnog ishoda povećan je kod bolesnika sa encefalitisom, visokim vrednostima serumskog CRP-a i proteinorahije.
Keywords: CSF; West Nile; encephalitis; leukocytes; meningitis.