Quantification of cerebrospinal fluid lactic acid in the differential diagnosis between HIV chronic meningitis and opportunistic meningitis

Abstract

Background Approximately 40% of HIV infected patients have chronic meningitis at various stages during the infection, 59% are asymptomatic. This is a diagnosis of exclusion and a confounding factor in cerebrospinal fluid (CSF) analysis, any other causes of chronic meningitis by opportunistic or co-infection must be ruled out. The aim of this study was to analyze CSF lactic acid (LA) as an adjuvant biomarker in chronic meningitis due to HIV. Methods CSF LA was quantified in 223 CSF samples by the Dimension AR (Dade Behring, Deerfield, IL, USA), distributed into nine groups: 1) HIV positive with an increase in CSF WBCs (n = 17); 2) HIV positive with normal CSF (n = 20); 3) enterovirus meningitis (n = 33); 4) Herpesviridae meningoencephalitis (n = 30); 5) fungal meningitis (n = 25); 6) tuberculosis (TB) meningitis (n = 17); 7) toxoplasmosis (n = 18); 8) neurosyphilis (n = 6); 9) control group (n = 57). Results CSF LA (median; IQR) was higher in samples with TB meningitis (5.5; 2.9–7.5 mmol/L) and Cryptococcus neoformans meningitis (3.9; 2.7–5.8 mmol/L) compated with samples with HIV chronic meningitis (1.7; 1.4–1.9 mmol/L) and other groups (p≤0.0001). For the diagnosis of HIV chronic meningitis, using a cut-off of 3.5 mmol/L, CSF LA showed high sensitivity and negative predictive value, although low specificity. Conclusions CSF LA helps to discriminate between C. neoformans or TB meningitis and HIV chronic meningitis: CSF LA can be included with the methods currently used to identify these specific pathogens, though it does not replace them. It is rapid, inexpensive and easy to perform, and can be used in developing countries.

Transient and asymptomatic meningitis in human immunodeficiency virus-1 subtype C: a case study of genetic compartmentalization and biomarker dynamics

“…The WBC count is less than that measured in the present case, with a median (IQR) count of 10 (8; 22) cells/mm 3 (de Almeida et al 2011). This is an exclusion diagnosis in which any other causes of chronic meningitis by opportunistic or co-infection must be ruled out (Marshall et al 1988; Hollander et al 1994).…”

Cerebrospinal fluid abnormalities in meningeosis neoplastica: a retrospective 12-year analysis

“…In a recent receiver operating characteristic (ROC) curve analysis, CSF lactate had the highest accuracy for discriminating bacterial from viral meningitis with a cutoff set at 3.5 mmol/l [18]. Using a cutoff of 3.5 mmol/l, CSF lactate was also very useful to discriminate between cryptococcal or tuberculous meningitis and HIV chronic meningitis [19]. In acute Lyme neuroborreliosis, an atypical bacterial CNS infection with low pathogen concentrations in CSF and symptoms, which may resemble meningeosis carcinomatosa (in particular, radicular lesions and cranial nerve involvement), only 5 of 118 patients (4%) had a CSF lactate ≥3.5 mmol/l, and the mean CSF lactate level was not elevated [20].…”

Cerebrospinal Fluid Lactate as a Prognostic Marker of Disease Severity and Mortality in Cryptococcal Meningitis

“…[1] However, despite the high sensitivity, CSF lactate measurements are highly nonspecific and are also found to be elevated in several other infectious and noninfectious neurological conditions, including cerebral malaria, tuberculous meningitis, cryptococcal meningitis, cerebral injury, subarachnoid hemorrhage, seizures, and ischemia. [3][4][5][6][7] As a diagnostic tool, the current recommended clinical application to use CSF lactate, as dictated by the Infectious Diseases Society of America guidelines, is in the diagnostic work up of bacterial meningitis after postoperative neurological procedures. [5,8] As a prognostic marker in cases of bacterial meningitis, individuals with higher CSF lactate levels demonstrate a trend towards lower Glasgow coma score and higher mortality.…”