ABSTRACT
BACKGROUND: The Kuopio University Hospital (KUH) idiopathic normal pressure hydrocephalus (iNPH) cerebrospinal fluid (CSF) shunting protocol is described together with the initial outcomes of 175 patients with probable iNPH treated according to this protocol from a defined population. Our secondary aim was to display the variety of differential diagnoses referred to the KUH iNPH outpatient clinic from 2010 until 2017. METHODS: Patients were divided into four groups according to the prognostic tests: tap test (positive or negative) and infusion test (positive or negative). The short-term outcome was compared between groups. The 3-month outcome following shunt surgery was assessed by measuring gait speed improvement, using a 12-point iNPH grading scale (iNPHGS) and the 15D instrument. RESULTS: From 341 patients suspected of iNPH, 88 patients were excluded from further research mostly due to deviation from the protocol's gait assessment guidelines. Hence 253 patients with suspected iNPH were included in the study, 177/253 (70%) of whom were treated with a CSF shunt. A favorable clinical outcome following surgery was observed in 79-93% of patients depending on the prognostic group. A moderate association (Cramer's V = 0.32) was found between the gait speed improvement rate and the prognostic group (X2, p = 0.003). Patients with a positive tap test had the highest gait speed improvement rate (75%). In addition, an improvement in walking speed was observed in 4/11 patients who had both a negative tap test and a negative infusion test. Other outcome measures did not differ between the prognostic groups. Conditions other than iNPH were found in 25% of the patients referred to iNPH outpatient clinic, with the most prevalent being Alzheimer's disease. CONCLUSIONS: Our results emphasize the importance of a systematic diagnostic and prognostic workup especially in cases with an atypical presentation of iNPH. Additional diagnostic testing may be required, but should not delay adequate care. Active surgical treatment is recommended in patients with a high clinical probability of iNPH. Other neurological conditions contributed to most of the non iNPH diagnoses.
Subject(s)
Cerebrospinal Fluid Shunts/methods , Hydrocephalus, Normal Pressure/diagnosis , Hydrocephalus, Normal Pressure/surgery , Aged , Female , Humans , Male , Treatment OutcomeABSTRACT
Behavioural variant frontotemporal dementia (bvFTD) and idiopathic normal pressure hydrocephalus (iNPH) are neurodegenerative diseases that can present with similar symptoms. These include decline in executive functions, psychomotor slowness, and behavioural and personality changes. Ventricular enlargement is a key radiological finding in iNPH that may also be present in bvFTD caused by the C9ORF72 expansion mutation. Due to this, bvFTD has been hypothesized as a potential comorbidity to iNPH but bvFTD patients have never been identified in studies focusing in clinical comorbidities with iNPH. Here we describe a patient with the C9ORF72 expansion-associated bvFTD who also showed enlarged ventricles on brain imaging. The main clinical symptoms were severe gait disturbances and psychiatric problems with mild cognitive decline. Cerebrospinal fluid removal increased the patient's walking speed, so a ventriculoperitoneal shunt was placed. After insertion of the shunt, there was a significant improvement in walking speed as well as mild improvement in cognitive function but not in neuropsychiatric symptoms relating to bvFTD. Comorbid iNPH should be considered in bvFTD patients who have enlarged ventricles and severely impaired gait.
