Arquivos de Neuro-Psiquiatria (Jul 2014)

Portable lactate analyzer for measuring lactate in cerebrospinal fluid (CSF) and plasma ? method-comparison evaluations

  • Sérgio Monteiro de Almeida,
  • Jennifer Marquie-Beck,
  • Archana Bhatt,
  • Scott Letendre,
  • Allen McCutchan,
  • Ron Ellis

DOI
https://doi.org/10.1590/0004-282X20140076
Journal volume & issue
Vol. 72, no. 7
pp. 500 – 505

Abstract

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Increased plasma lactate levels can indicate the presence of metabolic disorders in HIV infected individuals. Objective: To determine whether a portable analyzer is valid for measuring cerebrospinal fluid (CSF) and plasma lactate levels in HIV infected individuals. Method: CSF and plasma were collected from 178 subjects. Samples tested by the Accutrend® portable analyzer were compared to those tested by a reference device (SYNCHRON LX® 20). Results: The portable analyzer had in plasma sensitivity of 0.95 and specificity 0.87. For CSF the specificity was 0.95; the sensitivity 0.33; the negative predictive value was 95% and the positive predictive value 33%. Conclusions: These findings support the validity of the portable analyzer in measuring lactate concentrations in CSF that fall within the normal range. The relatively poor positive predictive value indicates that a result above the reference range may represent a “false positive test”, and should be confirmed by the reference device before concluding abnormality.

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