5th International Conference on Primary Care and Global Healthcare

Rohit Renjhen is an experienced consultant psychiatrist with over 17 years of practice, currently serving at the Midlands Partnership Foundation Trust since 2013. He completed his MBBS and Diploma in Psychological Medicine (DPM), followed by membership of the Royal College of Psychiatrists (MRCPsych) in 2005. He is also a Fellow of the Royal Society of Medicine (FRSM), which reflects his commitment to maintaining high standards in his practice and contributing to the advancement of medical knowledge. In addition to his clinical work, he holds a masters in medical law and ethics from De Montfort University Leicester (2018), which complements his extensive expertise in both psychiatry and medical ethics. He is a qualified trainer for the approved clinician course for capacity assessment in the elderly and is up-to-date with his deprivation of liberty safeguards training. His focus is on providing expert assessments, especially in the domains of functional and organic conditions in the elderly, ADHD in adults, and the complex issues surrounding capacity assessments for wills and power of attorney. His special interests include the management and assessment of complicated dementia cases, where his expertise in both clinical psychiatry and legal considerations allows him to provide comprehensive care and guidance. He is a respected member of two peer groups, ensuring that his knowledge and skills remain current and evidence-based. His well-rounded experience makes him a valuable asset to both his patients and the medical community.

Aims: To present a diagnostically complex case of late-onset psychiatric and behavioural disturbance associated with evolving neurocognitive and neurological pathology, highlighting the overlap between psychiatry, neurology, and neurodegenerative disease. The case demonstrates the challenge of distinguishing functional psychiatric illness from progressive organic pathology, particularly in suspected Normal Pressure Hydrocephalus (NPH), Parkinsonism, and mixed dementia.

Background: Psychiatric symptoms in older adults may represent prodromal manifestations of neurodegenerative or structural neurological disease. NPH is classically characterised by gait disturbance, cognitive impairment, and urinary incontinence; however, psychiatric symptoms such as psychosis, compulsive behaviours, apathy, and personality change may precede these features. This can result in delayed diagnosis and fragmented management across specialties.

Methods: A longitudinal review of psychiatric, neurological, neuroimaging, and collateral clinical information was undertaken during inpatient and outpatient care between 2024 and 2026. Data included serial cognitive assessments, MRI and PET imaging, behavioural observations, medication history, multidisciplinary reviews, and collateral history from family members. Relevant literature regarding psychiatric presentations of NPH and neurodegenerative disease was reviewed.

Outcome: The patient initially presented with fixed somatic delusions following spinal surgery and was treated for probable delusional disorder over several years. He later developed progressive executive dysfunction, impaired verbal fluency, emotional blunting, compulsive behaviours, gait disturbance, urinary symptoms, and marked sexual disinhibition. MRI demonstrated ventriculomegaly with temporal lobe atrophy, while PET imaging suggested mixed vascular and early Alzheimer-type changes. Differential diagnoses included behavioural variant frontotemporal dementia, Parkinson’s disease, mixed dementia, and NPH. Due to escalating behavioural disturbance and safeguarding concerns, he was detained under the Mental Health Act and referred for neurosurgical assessment, including consideration of cerebrospinal fluid drainage.

Conclusion: This case highlights the importance of repeated reassessment of late-onset psychiatric presentations for evolving organic pathology. NPH and neurodegenerative disorders may initially mimic primary psychiatric illness when behavioural symptoms predominate. Early multidisciplinary assessment, collateral history, and repeat neuroimaging are essential to avoid diagnostic delay and support timely intervention.