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Blood tests usually come back normal in affected individuals, so they do not serve as a reliable means of diagnosis. Blood tests can show low serum ferritin levels. However, this is unreliable as method of diagnosis, as some patients show typical serum ferritin levels even at the latest stages of neuroferritinopathy. Cerebral spinal fluid tests also are typically normal.
Ferritin found in the skin, liver, kidney, and muscle tissues may help in diagnosing neuroferritinopathy. More cytochrome c oxidase-negative fibers are also often found in the muscle biopsies of affected individuals.
Genetic testing can confirm a neuroferritinopathy diagnosis. A diagnosis can be made by analyzing the protein sequences of affected individuals and comparing them to known neuroferritinopathy sequences.
A neurological examination would show evidence of muscle rigidity; weakness; and abnormal postures, movements, and tremors. If other family members are also affected, this may help determine the diagnosis. Genetic tests can confirm an abnormal gene causing the disease. However, this test is not yet widely available. Other movement disorders and diseases must be ruled out. Individuals exhibiting any of the above listed symptoms are often tested using MRI (Magnetic Resonance Imaging) for a number of neuro-related disorders. As PKAN is a disease prominently evident in the brain, MRIs are very useful in making a sound diagnosis. An MRI usually shows iron deposits in the basal ganglia. Development of diagnostic criteria continues in the hope of further separating PKAN from other forms of neurodegenerative diseases featuring NBIA.
Microscopic features of PKAN include:
- Iron granules
- Spheroid bodies
- Lewy bodies within neurons
To gain a better understanding of the disease, researchers have retrospectively reviewed medical records of probands and others who were assessed through clinical examinations or questionnaires. Blood samples are collected from the families of the probands for genetic testing. These family members are assessed using their standard medical history, on their progression of Parkinson's like symptoms (Unified Parkinson's Disease Rating Scale), and on their progression of cognitive impairment such as dementia (Folstein Test).
Standard MRI scans have been performed on 1.5 Tesla scanners with 5 mm thickness and 5 mm spacing to screen for white matter lesions in identified families. If signal intensities of the MRI scans are higher in white matter regions than in grey matter regions, the patient is considered to be at risk for HDLS, although a number of other disorders can also produce white matter changes and the findings are not diagnostic without genetic testing or pathologic confirmation.
Children of affected individuals are obligate carriers for aceruloplasminemia. If the CP mutations has been identified in a related individual, prenatal testing is recommended. Siblings of those affected by the disease are at a 25% of aceruloplasminemia. In asymptomatic siblings, serum concentrations of hemoglobin and hemoglobin A1c should be monitored.
To prevent the progression of symptoms of the disease, annual glucose tolerance tests beginning in early teen years to evaluate the onset of diabetes mellitus. Those at risk should avoid taking iron supplements.
Diagnosis of this disorder depends on blood tests demonstrating the absence of serum ceruloplasmin, combined with low serum copper concentration, low serum iron concentration, high serum ferritin concentration, or increased hepatic iron concentration. MRI scans can also confirm a diagnosis; abnormal low intensities can indicate iron accumulation in the brain.
Protein function tests that demonstrate a reduce in chorein levels and also genetic analysis can confirm the diagnosis given to a patient. For a disease like this it is often necessary to sample the blood of the patient on multiple occasions with a specific request given to the haematologist to examine the film for acanthocytes. Another point is that the diagnosis of the disease can be confirmed by the absence of chorein in the western blot of the erythrocyte membranes.
A diagnosis of beta-mannosidosis is suspected based on the persons clinical presentation. Urine testing to identify abnormal oligosaccharides is a useful screening test, and enzymatic analysis or molecular testing can be used for confirmation.
Niemann–Pick type C is diagnosed by assaying cultured fibroblasts for cholesterol esterfication and staining for unesterified cholesterol with filipin. The fibroblasts are grown from a small skin biopsy taken from a patient with suspected NPC. The diagnosis can be confirmed by identifying mutations in the NPC1 or NPC2 genes in 80–90% of cases. This specialized testing is available at Thomas Jefferson University Lysosomal Disease Testing Lab and the Mayo Clinic.
Diagnostic techniques for this condition can be done to offer a DDx, via lectin histochemistry to distinguish between α-mannosidosis and beta-mannosidosis.
The lifespan of patients with NPC is usually related to the age of onset. Children with antenatal or infantile onset usually succumb in the first few months or years of life, whereas adolescent and adult onset forms of Niemann–Pick type C have a more insidious onset and slower progression, and affected individuals may survive to the seventh decade. Adult cases of NPC are being recognized with increasing frequency. It is suspected that many patients affected by NPC are undiagnosed, owing to lack of awareness of the disease and the absence of readily available screening or diagnostic tests. For the same reasons the diagnosis is often delayed by many years.
An effective treatment has yet to be found. In many cases electrical stimulation of the globus pallidus has been shown to produce improvement of dystonia severity, however it has not been shown to delay neurodegeneration. There is often overlap in the phenotypes of the symptoms both between different NBIA disorders and between NBIA and other disorders, leading to misdiagnoses. Treatments typically treat or ameliorate the symptoms and do not address the accumulation of iron. Psychotherapy, such as dopaminergic drugs, anticholinergics, tetrabenazine, is often used to treat the symptoms but does not improve the long term outcome of the patient.
The group includes the following disorders:
- Pantothenate kinase-associated neurodegeneration (PKAN) also known as neurodegeneration with brain iron accumulation 1 (NBIA1) and Hallervorden–Spatz syndrome
- PLAN (PLA2G6-associated neurodegeneration)
- MPAN (Mitochondrial membrane protein-associated neurodegeneration)
- BPAN (Beta-propeller protein-associated neurodegeneration)
- FAHN (Fatty acid hydroxylase-associated neurodegeneration)
- Kufor–Rakeb syndrome
- Neuroferritinopathy
- Aceruloplasminemia
- Woodhouse–Sakati syndrome
- CoPAN (CoA synthase protein-associated neurodegeneration)
- Idiopathic NBIA
- Neurodegeneration with brain iron accumulation 2B (NBIA2B)
- Neurodegeneration with brain iron accumulation 3 (NBIA3)
CT and MRI are most commonly used to observe the brain for cerebral atrophy. A CT scan takes cross sectional images of the brain using X-rays, while an MRI uses a magnetic field. With both measures, multiple images can be compared to see if there is a loss in brain volume over time.
Cerebral atrophy can be hard to distinguish from hydrocephalus because both cerebral atrophy and hydrocephalus involve an increase in cerebrospinal fluid (CSF) volume. In cerebral atrophy, this increase in CSF volume comes as a result of the decrease in cortical volume. In hydrocephalus, the increase in volume happens due to the CSF itself.
Neurodegeneration with brain iron accumulation (NBIA) is a group of inherited neurological disorders in which iron accumulates in the basal ganglia, resulting in progressive dystonia, Parkinsonism, spasticity, optic atrophy or retinal degeneration and neuropsychiatric abnormalities. NBIA disorders have been associated with genes in synapse and lipid metabolism related pathways. Describes a group of disorders characterized by an accumulation of brain iron and the presence of axonal spheroids in the central nervous system. Iron accumulation can occur any where in the brain, with accumulation typically occurring in globus pallidus, substantia nigra, pars reticula, striatum and cerebellar dentate nuclei. Symptoms can include various movement disorders, seizures, visual disturbances, and cognitive decline, usually in combination. The known causes of NBIA disorders are mutations in genes directly involved in iron metabolism, impaired phospholipid and ceramide metabolism, lysosomal disorders, as well as mutations in genes with unknown functions. Onset can occur at different ages, from early childhood to late adulthood. Magnetic resonance imaging (MRI) is used to distinguish between the different forms of NBIA due to the accumulation of iron in different areas of the brain. Patients typically fall into two different categories: (1) early onset, rapid progression or (2) late onset, slow progression. The first type is considered to be the classic presentation, while the second type is the atypical presentation. Phenotypes of the different disorders appear to be dependent on age, i.e. amount of iron accumulation and cognitive ability.
Diagnosis is suspected clinically and family history, neuroimaging and genetic study helps to confirm Behr Syndrome.
Of the many medical imaging techniques available, single photon emission computed tomography (SPECT) appears to be superior in differentiating Alzheimer's disease from other types of dementia, and this has been shown to give a greater level of accuracy compared with mental testing and medical history analysis. Advances have led to the proposal of new diagnostic criteria.
PiB PET remains investigational, but a similar PET scanning radiopharmaceutical called florbetapir, containing the longer-lasting radionuclide fluorine-18, has recently been tested as a diagnostic tool in Alzheimer's disease, and given FDA approval for this use.
Amyloid imaging is likely to be used in conjunction with other markers rather than as an alternative. Volumetric MRI can detect changes in the size of brain regions. Measuring those regions that atrophy during the progress of Alzheimer's disease is showing promise as a diagnostic indicator. It may prove less expensive than other imaging methods currently under study.
In 2011 An FDA panel voted unanimously to recommend approval of florbetapir, which is currently used in an investigational study. The imaging agent can help to detect Alzheimer's brain plaques, but will require additional clinical research before it can be made available commercially.
Diffuse, symmetric white matter abnormalities were demonstrated by magnetic resonance imaging (MRI) suggesting that Behr syndrome may represent a disorder of white matter associated with an unknown biochemical abnormality.
Emphasis in Alzheimer's research has been placed on diagnosing the condition before symptoms begin. A number of biochemical tests have been developed to attempt earlier detection. One such test involves the analysis of cerebrospinal fluid for beta-amyloid or tau proteins, both total tau protein and phosphorylated tau protein concentrations.
The treatment to battle the disease chorea-acanthocytosis is completely symptomatic. For example, Botulinum toxin injections can help to control orolingual dystonia.
Deep Brain Stimulation is a treatment that has varied effects on the people suffering from the symptoms of this disease, for some it has helped in a large way and for other people it did not help whatsoever, it is more effective on specific symptoms of the disease. Patients with chorea-acanthocytosis should undergo a cardiac evaluation every 5 years to look for cardiomyopathy.
Genetic testing is available for symptomatic individuals and asymptomatic relatives.
Diagnosis of mitochondrial trifunctional protein deficiency is often confirmed using tandem mass spectrometry. It should be noted that genetic counseling is available for this condition. Additionally the following exams are available:
- CBC
- Urine test
Menkes syndrome can be diagnosed by blood tests of the copper and ceruloplasmin levels, skin biopsy, and optical microscopic examination of the hair to view characteristic Menkes abnormalities. X-rays of the skull and skeleton are conducted to look for abnormalities in bone formation. Urine homovanillic acid/vanillylmandelic acid ratio has been proposed as a screening tool to support earlier detection. Since 70% of MNK cases are inherited, genetic testing of the mother can be performed to search for a mutation in the ATP7A gene.