Cerebrospinal fluid lactate as a predictive biomarker for tuberculous meningitis diagnosis

Cerebrospinal Fluid Biomarkers of Symptomatic Neurosyphilis in People With HIV Compared with Uninfected Individuals

We evaluated the diagnostic clinical performance characteristics (DCPC) of cerebrospinal fluid (CSF) total protein (TP), white blood cell count (WBC), and lactate (LA) with different cutoff points as adjunct biomarkers of confirmed or presumptive symptomatic neurosyphilis (NS) and the impact of HIV infection. From 5,640 participants who underwent lumbar punctures, 236 participants were included, and classified as either people with HIV (PWH) or people without HIV (PWoH) according to the CDC criteria for confirmed NS (n = 42), presumptive NS (n = 74), systemic syphilis (SS) (n = 38), serological diagnosis of syphilis (n = 18), PWH without SS and NS (n = 10), and negative control (n = 72). In PWoH, for presumptive NS, the combination of CSF TP > 45 mg/dL and/or WBC > 5.0 cells/mm3 is valuable for screening, whereas in PWH, it is not recommended for either screening or case-finding NS, however the DCPC were better in the suppressed group. In PWoH, the value of CSF TP > 45 mg/dL is adequate for both screening and confirmation of presumptive NS, subject to prevalence. For WBC count > 20 cell/mm3, the positive predictive value (PPV) of the test is almost perfect, suggesting a confirmatory test. In PWH, CSF TP is an inadequate marker of NS. The WBC count, with cutoffs of > 10 or > 20 cells/mm3, was moderately applicable for screening.As conclusions: CSF WBC count and TP showed distinct DCPC in confirmed or presumptive NS, better in the former. These biomarkers could be included for presumptive NS diagnosis. DCPC of these biomarkers for the diagnosis of NS is greatly affected by HIV co-infection.

Cytokine profile in patients with acute bacterial meningitis

BACKGROUND

Bacterial meningitis is a life-threatening disease with high mortality and common long-term sequelae. The inflammatory response in the subarachnoid space, modulated by different cytokines, plays a major role in the pathogenesis of acute central nervous system infections. We aimed to examine correlations of interleukin (IL)-6, IL-8, IL-10, IL-12(p40), and tumor necrosis factor (TNF)-α levels with disease severity, complications, and outcome in patients with acute bacterial meningitis.

METHODS

The study involved 30 patients with bacterial meningitis/meningoencephalitis admitted to the University Hospital St. George, Plovdiv over a period of 4 years. Patients were selected based on clinical presentation and laboratory abnormalities, consistent with a neuroinfection. Enzyme-linked immunosorbent assay was used to measure the studied cytokines in both cerebrospinal fluid (CSF) and serum in parallel. For microbiological diagnosis multiplex, polymerase chain reaction, and CSF culture were used.

RESULTS

In patients with acute bacterial meningitis CSF levels of IL-6, IL-8, IL-10, and TNF-α are significantly increased than in serum. CSF TNF-α, CSF IL-8, and CSF IL-10 had a moderate negative correlation to CSF glucose. It was found that serum IL-8 is significantly elevated in patients who experienced neurological complications, have severe clinical course, and in deceased patients. CSF IL-10 is increased only in patients with severe acute bacterial meningitis.

CONCLUSION

Among patients with acute bacterial meningitis serum IL-8 could delineate these with increased risk of neurological complications, severe clinical course, and fatal outcome. Serum IL-8 and CSF IL-10 could be used as indicators of disease severity.