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.

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.

Embryos produced using in vitro fertilization may be genetically tested for HD using preimplantation genetic diagnosis (PGD). This technique, where one or two cells are extracted from a typically 4- to 8-cell embryo and then tested for the genetic abnormality, can then be used to ensure embryos affected with HD genes are not implanted, and therefore any offspring will not inherit the disease. Some forms of preimplantation genetic diagnosis—non-disclosure or exclusion testing—allow at-risk people to have HD-free offspring "without" revealing their own parental genotype, giving no information about whether they themselves are destined to develop HD. In exclusion testing, the embryos' DNA is compared with that of the parents and grandparents to avoid inheritance of the chromosomal region containing the HD gene from the affected grandparent. In non-disclosure testing, only disease-free embryos are replaced in the uterus while the parental genotype and hence parental risk for HD are never disclosed.

It is also possible to obtain a prenatal diagnosis for an embryo or fetus in the womb, using fetal genetic material acquired through chorionic villus sampling. An amniocentesis can be performed if the pregnancy is further along, within 14–18 weeks. This procedure looks at the amniotic fluid surrounding the baby for indicators of the HD mutation. This, too, can be paired with exclusion testing to avoid disclosure of parental genotype. Prenatal testing can be done when a parent has been diagnosed with HD, when they have had genetic testing showing the expansion of the HTT gene, or when they have a 50% chance of inheriting the disease. The parents can be counseled on their options, which include termination of pregnancy, and on the difficulties of a child with the identified gene.

In addition, in at-risk pregnancies due to an affected male partner, non-invasive prenatal diagnosis can be performed by analyzing cell-free fetal DNA in a blood sample taken from the mother (via venipuncture) between six and twelve weeks of pregnancy. It has no procedure-related risk of miscarriage (excepting via needle contamination).

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.

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.

The types of imaging techniques that are most prominently utilized when studying and/or diagnosing CBD are:

- magnetic resonance imaging (MRI)

- single-photon emission computed tomography (SPECT)

- fluorodopa positron emission tomography (FDOPA PET)

Developments or improvements in imaging techniques provide the future possibility for definitive clinical diagnosis prior to death. However, despite their benefits, information learned from MRI and SPECT during the beginning of CBD progression tend to show no irregularities that would indicate the presence of such a neurodegenerative disease. FDOPA PET is used to study the efficacy of the dopamine pathway.

Despite the undoubted presence of cortical atrophy (as determined through MRI and SPECT) in individuals experiencing the symptoms of CBD, this is not an exclusive indicator for the disease. Thus, the utilization of this factor in the diagnosis of CBD should be used only in combination with other clinically present dysfunctions.

Due to the condition's rarity, it is frequently misdiagnosed, often as cerebral palsy. This results in patients often living their entire childhood with the condition untreated.

The diagnosis of SS can be made from a typical history, a trial of dopamine medications, and genetic testing. Not all patients show mutations in the GCH1 gene (GTP cyclohydrolase I), which makes genetic testing imperfect.

Sometimes a lumbar puncture is performed to measure concentrations of biopterin and neopterin, which can help determine the exact form of dopamine-responsive movement disorder: early onset parkinsonism (reduced biopterin and normal neopterin), GTP cyclohydrolase I deficiency (both decreased) and tyrosine hydroxylase deficiency (both normal).

In approximately half of cases, a phenylalanine loading test can be used to show decreased conversion from the amino acid phenylalanine to tyrosine. This process uses BH4 as a cofactor.

During a sleep study (polysomnography), decreased twitching may be noticed during REM sleep.

An MRI scan of the brain can be used to look for conditions that can mimic SS (for example, metal deposition in the basal ganglia can indicate Wilson's disease or pantothenate kinase-associated neurodegeneration). Nuclear imaging of the brain using positron emission tomography (PET scan) shows a normal radiolabelled dopamine uptake in SS, contrary to the decreased uptake in Parkinson's disease.

Other differential diagnoses include metabolic disorders (such as GM2 gangliosidosis, phenylketonuria, hypothyroidism, Leigh disease) primarily dystonic juvenile parkinsonism, autosomal recessive early onset parkinsonism with diurnal fluctuation, early onset idiopathic parkinsonism, focal dystonias, dystonia musculorum deformans and dyspeptic dystonia with hiatal hernia.

- Diagnosis - main

- typically referral by GP to specialist Neurological Hospital e.g. National Hospital in London.

- very hard to diagnose as condition is dynamic w.r.t. time-of-day AND dynamic w.r.t. age of patient.

- correct diagnosis only made by a consultant neurologist with a complete 24-hour day-cycle observation(with video/film) at a Hospital i.e. morning(day1)->noon->afternoon->evening->late-night->sleep->morning(day2).

- patient with suspected SS required to walk in around hospital in front of Neuro'-consultant at selected daytime intervals to observe worsening walking pattern coincident with increased muscle tension in limbs.

- throughout the day, reducing leg-gait, thus shoe heels catching one another.

- diurnal affect of condition: morning(fresh/energetic), lunch(stiff limbs), afternoon(very stiff limbs), evening(limbs worsening), bedtime(limbs near frozen).

- muscle tension in thighs/arms: morning(normal), lunch(abnormal), afternoon(very abnormal), evening(bad), bedtime(frozen solid).

- Diagnosis - additional

- lack of self-esteem at school/college/University -> eating disorders in youth thus weight gains.

- lack of energy during late-daytime (teens/adult) -> compensate by over-eating.

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)

One of the most significant problems associated with CBD is the inability to perform a definitive diagnosis while an individual exhibiting the symptoms associated with CBD is still alive. A clinical diagnosis of CBD is performed based upon the specified diagnostic criteria, which focus mainly on the symptoms correlated with the disease. However, this often results in complications as these symptoms often overlap with numerous other neurodegenerative diseases. Frequently, a differential diagnosis for CBD is performed, in which other diseases are eliminated based on specific symptoms that do not overlap. However, some of the symptoms of CBD used in this process are rare to the disease, and thus the differential diagnosis cannot always be used.

Postmortem diagnosis provides the only true indication of the presence of CBD. Most of these diagnoses utilize the Gallyas-Braak staining method, which is effective in identifying the presence of astroglial inclusions and coincidental tauopathy.

Different genetic causes and types of Leigh syndrome have different prognoses, though all are poor. The most severe forms of the disease, caused by a full deficiency in one of the affected proteins, cause death at a few years of age. If the deficiency is not complete, the prognosis is somewhat better and an affected child is expected to survive 6–7 years, and in rare cases, to their teenage years.

Other diseases can have a similar clinical presentation to Leigh syndrome; excluding other causes of similar clinical symptoms is often a first step to diagnosing Leigh disease. Conditions that can appear similar to Leigh disease include perinatal asphyxia, kernicterus, carbon monoxide poisoning, methanol toxicity, thiamine deficiency, Wilson's disease, biotin-responsive basal ganglia disease, and some forms of encephalitis. Perinatal asphyxia can cause bilateral ganglial lesions and damage to the thalamus, which are similar to the signs seen with Leigh syndrome. When hyperbilirubinemia is not treated with phototherapy, the bilirubin can accumulate in the basal ganglia and cause lesions similar to those seen in Leigh syndrome. This is not common since the advent of phototherapy.

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.

CARASIL is diagnosed by MRI scans of the brain. Diffuse white matter changes (leukoencephalopathy) and multiple lacunar infarcts in basal ganglia of thalamus are usually determining factors seen on MRI scans of affected individuals. Further genetic testing can be used to confirm the presence of the disease.

A 2006 study of 279 patients found that of those with symptoms (185, 66%), 95% had suffered an encephalopathic crises usually with following brain damage. Of the persons in the study, 49 children died and the median age of death was 6.6 years. A Kaplan-Meier analysis of the data estimated that about 50% of symptomatic cases would die by the age of 25.

Currently, no treatment slows the neurodegeneration in any of the neuroacanthocytosis disorders. Medication may be administered to decrease the involuntary movements produced by these syndromes. Antipsychotics are used to block dopamine, anticonvulsants treat seizures and botulinum toxin injections may control dystonia. Patients usually receive speech, occupational and physical therapies to help with the complications associated with movement. Sometimes, physicians will prescribe antidepressants for the psychological problems that accompany neuroacanthocytosis. Some success has been reported with Deep brain stimulation.

Mouthguards and other physical protective devices may be useful in preventing damage to the lips and tongue due to the orofacial chorea and dystonia typical of chorea acanthocytosis.

In those with SS, symptoms typically dramatically improve with low-dose administration of levodopa (L-dopa). L-DOPA exists as a biochemically significant metabolite of the amino acid phenylalanine, as well as a biological precursor of the catecholamine dopamine, a neurotransmitter. (Neurotransmitters are naturally produced molecules that may be sequestered following the propagation of an action potential down a nerve towards the axon terminal, which in turn may cross the synaptic junction between neurons, enabling neurons to communicate in a variety of ways.) Low-dose L-dopa usually results in near-complete or total reversal of all associated symptoms for these patients. In addition, the effectiveness of such therapy is typically long term, without the complications that often occur for those with Parkinson's disease who undergo L-dopa treatment. Thus, most experts indicate that this disorder is most appropriately known as dopa-responsive dystonia (SS).

No data are available on mortality associated with SS, but patients surviving beyond the fifth decade with treatment have been reported. However, in severe, early autosomal recessive forms of the disease, patients have been known to pass away during childhood. Girls seem to be somewhat more commonly affected. The disease less commonly begins during puberty or after age 20, and very rarely, cases in older adults have been reported.

Due to commonly being misdiagnosed, it is common for the disease to remain untreated. When left untreated, patients often need achilles tendon surgery by the age of 21. They will also struggle with walking, an ability that will degrade throughout the day. Power napping can provide temporary relief in untreated patients. It also impairs development into adulthood, reduces balance, and reduces calf muscle development. Socially, it can result in depression, lack of social skills, and inability to find employment.

Stress caused by infection, fever or other demands on the body may lead to worsening of the signs and symptoms, with only partial recovery.

Computed tomography (CT) scans of people with PD usually appear normal. MRI has become more accurate in diagnosis of the disease over time, specifically through iron-sensitive T2* and SWI sequences at a magnetic field strength of at least 3T, both of which can demonstrate absence of the characteristic 'swallow tail' imaging pattern in the dorsolateral substantia nigra. In a meta-analysis, absence of this pattern was 98% sensitive and 95% specific for the disease. Diffusion MRI has shown potential in distinguishing between PD and Parkinson plus syndromes, though its diagnostic value is still under investigation. CT and MRI are also used to rule out other diseases that can be secondary causes of parkinsonism, most commonly encephalitis and chronic ischemic insults, as well as less frequent entities such as basal ganglia tumors and hydrocephalus.

Dopamine-related activity in the basal ganglia can be directly measured with PET and SPECT scans. A finding of reduced dopamine-related activity in the basal ganglia can rule out drug-induced parkinsonism, but reduced basal ganglia dopamine-related activity is seen in both PD and the Parkinson-plus disorders so these scans are not reliable in distinguishing PD from other neurodegenerative causes of parkinsonism.

Treatment depends upon the underlying disorder. Movement disorders have been known to be associated with a variety of autoimmune diseases.

The treatment of 2-Hydroxyglutaric aciduria is based on seizure control, the prognosis depends on how severe the condition is.

Research is underway worldwide to increase scientific understanding of these disorders as well to identify prevention and treatment methods. Known genetic mutations provide a basis for studying some of the conditions.

Magnetic Resonance Imaging (MRI) in one family showed mild atrophy of the cranial vermis as well as a small pons. Different types of atrophy including cerebellar in four individuals and basal ganglia has been evident through MRIs.