Evaluation of coexistence of Alzheimer’s disease in idiopathic normal pressure hydrocephalus using ELISA analyses for CSF biomarkers

Jun Young Choi,In Soo Joo,Young Chul Youn,Hyun Young Lee,Kyoon Huh,Tae Sung Lim,Byung Gon Kim,Sun Ah Park,So Young Moon

doi:10.1186/1471-2377-14-66

Abstract

BackgroundWe investigated levels of the β-amyloid 1–42 (Aβ42), total tau protein (T-tau) and tau phosphorylated at position threonine 181 (P-tau) in cerebrospinal fluid (CSF) of idiopathic normal pressure hydrocephalus (iNPH) patients and tried to find their clinical implications in the evaluation and treatment of iNPH.MethodTwenty-five possible iNPH patients were prospectively enrolled and their CSF was collected to analyze levels of Aβ42, T-tau and P-tau using ELISA method. Gait disturbance, urinary incontinence, and cognitive impairment were semi-quantified and detailed neuropsychological (NP) test was performed.ResultEight iNPH patients were classified into the lower CSF Aβ42 group and 17 patients were classified into the higher CSF Aβ42 group. There was no difference in the iNPH grading score and its improvement after LP between the two groups. The lower CSF Aβ42 group showed more deficits in attention, visuospatial function and verbal memory in the baseline NP test and less improvement in phonemic categorical naming and frontal inhibitory function after LP.ConclusionsOur study suggested that concomitant AD in iNPH patients might contribute to lumbar puncture or shunt unresponsiveness, especially in the field of cognitive dysfunction.

Highlights

We investigated levels of the β-amyloid 1–42 (Aβ42), total tau protein (T-tau) and tau phosphorylated at position threonine 181 (P-tau) in cerebrospinal fluid (CSF) of idiopathic normal pressure hydrocephalus patients and tried to find their clinical implications in the evaluation and treatment of iNPH
Our study suggested that concomitant Alzheimer’s disease (AD) in iNPH patients might contribute to lumbar puncture or shunt unresponsiveness, especially in the field of cognitive dysfunction
Since the introduction of ELISA method to detect cerebrospinal fluid (CSF) biomarkers for AD, there have been many studies about the differential role of levels of the β-amyloid 1–42 (Aβ42), T-tau protein (T-tau) and tau phosphorylated at position threonine 181 (P-tau) in CSF of iNPH patients [11,12,13,14,15]

Summary

Introduction

We investigated levels of the β-amyloid 1–42 (Aβ42), total tau protein (T-tau) and tau phosphorylated at position threonine 181 (P-tau) in cerebrospinal fluid (CSF) of idiopathic normal pressure hydrocephalus (iNPH) patients and tried to find their clinical implications in the evaluation and treatment of iNPH. Idiopathic normal pressure hydrocephalus (iNPH) is characterized by a clinical triad of symptoms including cognitive impairment, gait difficulty, and urinary incontinence along with ventricular enlargement in brain imaging [1,2]. It is a potentially reversible cause of cognitive and motor impairment in older adults using ventriculo-peritoneal (VP) shunt or ventriculo-atrial (VA) shunt operation. There are still debates about the level of each biomarker in two diseases and the implication of their changes [16,17]

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