Normal Pressure Hydrocephalus Overview

A neurological condition characterized by a triad of symptoms: broad-based gait (walking with an unsteady, wide-legged stance), frontal subcortical syndrome (slowed thinking, apathy, and difficulty with executive functions), and urinary incontinence.

The obstruction of cerebrospinal fluid (CSF) flow, often without a clear cause, leading to the accumulation of CSF within the brain's ventricles.

NPH's distinguishing feature: the pressure within the ventricles remains normal or even low despite the symptoms.

The brain's ventricles appear larger than expected compared to the amount of cortical atrophy (brain shrinkage) on imaging, along with periventricular signal changes (abnormal signals around the ventricles).

NPH needs to be differentiated from other conditions that may present similar symptoms, such as depression with pseudodementia or degenerative dementia.

In cases of NPH with recent onset and significant gait disturbance, a neurosurgical shunt procedure can improve CSF circulation by diverting excess CSF to another area of the body.

A lack of oxygen, often caused by conditions like suffocation or respiratory distress.

A state of abnormally low blood sugar levels.

A condition caused by inhaling carbon monoxide, often leading to brain injury.

The hippocampus and globus pallidus, regions of the brain involved in memory, learning, and movement control, are particularly vulnerable to damage from anoxia, hypoglycemia, and carbon monoxide poisoning.

The recovery time following anoxia, hypoglycemia, or carbon monoxide poisoning is generally shorter than that after traumatic brain injury, with less severe neurological consequences.

While uncommon, Parkinsonism, characterized by tremor, rigidity, and slow movement, can sometimes develop after a period of latency following anoxia, hypoglycemia, or carbon monoxide poisoning.

Memory impairments are the most common cognitive deficits observed in patients recovering from anoxia, hypoglycemia, or carbon monoxide poisoning.

Carbon monoxide poisoning is frequently caused by self-harm through exposure to car exhaust or accidental exposure due to poor ventilation in gas appliances or fires.

The severity of complications following carbon monoxide poisoning varies widely; residual symptoms, such as headaches, fatigue, and memory problems, can persist even in individuals who did not lose consciousness during the poisoning.

An autoimmune disease in which the body's immune system mistakenly attacks its own tissues, leading to inflammation and damage to various organs.

Neuropsychiatric symptoms, such as cognitive impairment, mood disorders, and psychosis, affect a significant portion of individuals with SLE.

About 10% of individuals experience neuropsychiatric symptoms at the initial presentation of SLE, while this figure rises to 20-75% during the course of the disease.

Cognitive dysfunction is the most prominent neuropsychiatric symptom in SLE, affecting areas such as memory, attention, concentration, and psychomotor speed (the speed of mental and physical processes).

Secondary neuropsychiatric syndromes are those that arise as a consequence of an underlying medical condition.

Secondary disorders are defined either by an underlying pathology (e.g., dementia) or a biological basis (e.g., epilepsy).

Some conditions not typically classified as neuropsychiatric can also be explained by biological mechanisms. For instance, fatigue and anxiety may result from physical illness.

The classification of secondary neuropsychiatric syndromes varies between the International Statistical Classification of Diseases and Related Health Problems (ICD-10) and the Diagnostic and Statistical Manual of Mental Disorders (DSM-5).

Secondary neuropsychiatric disorders arise from brain diseases, whereas those stemming from systemic (body-wide) diseases are categorized separately.

Features of secondary neuropsychiatric disorders often resemble those of primary (true) psychiatric disorders, making differentiation challenging.

Indicators suggesting a secondary syndrome include the presence of cerebral disease or dysfunction, a temporal relationship between the onset of physical and psychiatric conditions, and improvement in psychiatric symptoms after treating the underlying cause.

Conditions like temporal lobe disorders, Huntington's disease, basal ganglia lesions, and infections like neurosyphilis can be linked to psychosis.

Conditions like Alzheimer's disease, stroke, head trauma, multiple sclerosis, and metabolic disorders are often associated with mood disorders like depression and anxiety.

Frontotemporal dementias and various neurological conditions can trigger personality changes, leading to noticeable shifts in behavior, communication, and social interaction.

Obsessive-compulsive behaviors (repetitive thoughts and actions) are observed in individuals with frontotemporal dementias and basal ganglia disorders.

Multiple sclerosis (MS) is a common cause of chronic neurological disability in young adults.

Early diagnosis of MS can be challenging as physical symptoms may be misdiagnosed as psychiatric issues.

MS patients frequently experience psychiatric symptoms like fatigue and depression, with a significant risk of suicide.

The lifetime risk of depression among MS patients is 50%, independent of the clinical severity of the disease and the location of lesions in the brain.

Cognitive impairment impacts at least 40% of MS patients, possibly suggesting the presence of early or progressive disease.

Cognitive deficits in MS patients correlate with MRI findings of greater lesion load (damage to brain tissue) and callosal atrophy (shrinkage of the corpus callosum, a major communication pathway in the brain).

Encephalitis is defined as inflammation of the brain tissue, caused either by primary viral infections or autoimmune responses.

Herpes simplex virus is a common viral cause of encephalitis, and prompt treatment is crucial to prevent serious complications.

Early symptoms of encephalitis include headache, vomiting, altered consciousness, and seizures, making it essential to seek immediate medical attention.

Chronic complications following encephalitis can range from prolonged anxiety and depression to amnesic syndromes (memory problems), making ongoing care essential.

Autoimmune encephalitis, a growing area of recognition, involves autoantibodies (antibodies attacking the body's own tissues) directed at neuronal proteins, leading to psychiatric symptoms like delirium and psychosis.

Autoimmune encephalitis can present with psychiatric symptoms like delirium and psychosis, making early diagnosis and treatment crucial.