Hereditary spastic paraplegias can be classified based on the symptoms; mode of inheritance; the patient’s age at onset; the affected genes; and biochemical pathways involved.

Clinical diagnosis is conducted on individuals with age onset between late teens and late forties who show the initial characteristics for the recessive autosomal cerebellar ataxia.

The following tests are performed:

- MRI brain screening for cerebellum atrophy.

- Molecular genetic testing for SYNE-1 sequence analysis.

- Electrophysiologic studies for polyneurotherapy

- Neurological examination

Prenatal diagnosis and preimplantation genetic diagnosis (PGD) can be performed to identify the mothers carrying the recessive genes for cerebellar ataxia.

Initial diagnosis of HSPs relies upon family history, the presence or absence of additional signs and the exclusion of other nongenetic causes of spasticity, the latter being particular important in sporadic cases.

Cerebral and spinal MRI is an important procedure performed in order to rule out other frequent neurological conditions, such as multiple sclerosis, but also to detect associated abnormalities such as cerebellar or corpus callosum atrophy as well as white matter abnormalities. Differential diagnosis of HSP should also exclude spastic diplegia which presents with nearly identical day-to-day effects and even is treatable with similar medicines such as baclofen and orthopedic surgery; at times, these two conditions may look and feel so similar that the only "perceived" difference may be HSP's hereditary nature versus the explicitly non-hereditary nature of spastic diplegia (however, unlike spastic diplegia and other forms of spastic cerebral palsy, HSP cannot be reliably treated with selective dorsal rhizotomy).

Ultimate confirmation of HSP diagnosis can only be provided by carrying out genetic tests targeted towards known genetic mutations.

Different types of ataxia:

- congenital ataxias (developmental disorders)

- ataxias with metabolic disorders

- ataxias with a DNA repair defect

- degenerative ataxias

- ataxia associated with other features.

Neuroimaging like MRI is important. However, there was considerable intrafamilial variability regarding neuroimaging, with some individuals showing normal MRI findings. Early individual prognosis of such autosomal recessive cerebellar ataxias is not possible from early developmental milestones, neurological signs, or neuroimaging.

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.

Diagnosis is suspected clinically and family history, neuroimaging and genetic study helps to confirm Behr Syndrome.

Detection of the disorder is possible with an organic acid analysis of the urine. Patients with SSADH deficiency will excrete high levels of GHB but this can be difficult to measure since GHB has high volatility and may be obscured on gas chromatography or mass spectrometry studies by a high urea peak. Other GABA metabolites can also be identified in urine such as glycine. Finally, succinic semialdehyde dehydrogenase levels can be measured in cultured leukocytes of the patient. This occurs due to the accumulation of 4,5-dihydroxyhexanoic acid which is normally undetectable in mammalian tissues but is characteristic of SSADH deficiency. This agent can eventually compromise the pathways of fatty acid, glycine, and pyruvate metabolism, and then become detectable in patients' leukocytes. Such enzyme levels can also be compared to non-affected parents and siblings.

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

Brain MRI shows vermis atrophy or hypoplasic. Cerebral and cerebellar atrophy with white matter changes in some cases.

In diagnosing autosomal dominant cerebellar ataxia the individuals clinical history or their past health examinations, a current physical examination to check for any physical abnormalities, and a genetic screening of the patients genes and the genealogy of the family are done. The large category of cerebellar ataxia is caused by a deterioration of neurons in the cerebellum, therefore magnetic resonance imaging (MRI) is used to detect any structural abnormality such as lesions which are the primary cause of the ataxia. Computed tomography (CT) scans can also be used to view neuronal deterioration, but the MRI provides a more accurate and detailed picture.

A prenatal diagnostic is possible and very reliable when mother is carrier of the syndrome. First, it's necessary to determine the fetus' sex and then study X-chromosomes. In both cases, the probability to transfer the X-chromosome affected to the descendants is 50%. Male descendants who inherit the affected chromosome will express the symptoms of the syndrome, but females who do will be carriers.

Elevated levels of serum cholestanol are diagnostic of CTX. Alternatively analysis of 27-hydroxycholesterol and 7 alpha hydroxycholesterol can be used. Genetic testing of the CYP27A1 gene is confirmatory and is increasingly being used as a first line test as part of symptom specific gene panels (genetic eye disease, ataxia, dementia).

The inheritance pattern is autosomal recessive. The disorder is caused by a mutation in the SGCG on chromosome 13. The mutation of the SACS gene causes the production of an unstable, poorly functioning SACSIN protein. It is unclear as to how this mutation affects the central nervous system (CNS) and skeletal muscles presenting in the signs and symptoms of ARSACS.

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.

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.

There is no known prevention of spinocerebellar ataxia. Those who are believed to be at risk can have genetic sequencing of known SCA loci performed to confirm inheritance of the disorder.

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).

A diagnosis can be made on the combination of clinical features. This can then be confirmed by gene sequencing.

Cranial computed topography, magnetic resonance imaging, and flurodeoxyglucose positron emission topography are just some of the neuroimaging modalities that have been used to diagnose patients with SSADH deficiency. On the basis of 29 previously published cases that had imaging results available, there were some common abnormalities found. These included increased T2-weighted signal abnormalities involving the globus pallidi bilaterally and symmetrically as well as the presence of subcortical white matter. Similar abnormalities have been identified in the brainstem and cerebellar dentate nucleus.

Signal intensity on a T2 image may be a result of edema or an inflammatory response. Because this type of imaging is a water detecting sequence, any form of calcification or mineralization would also appear dark, thus explaining why accumulation of extra blood or fluid would appear bright on a T2 image. Another explanation for signal intensity may be demyelination since the globus pallidi are traversed by a number of myelinated axons, thus confirming Ren and Mody’s 2003 work proving that repeated exposure of GHB to MAP kinase affected myelin expression, thus causing the numerous neurological dysfunctions seen in SSADH deficiency patients. Ultimately, because the globus pallidus is intimately linked with the basal ganglia and thalamus, it would be expected that some of the motor dysfunctions seen in SSADH patients such as ataxia and hyporeflexia would be common.

Three dimensional (3D) T1W, Axial, coronal, sagittal imaging is excellent for differentiation between gray matter and white matter acquisition of high-resolution anatomic information.T2W, Axial and coronal imaging for acquisition of high-resolution anatomic information; delineation of cortex, white matter, and gray matter nuclei. Diffusion tensor, axial imaging is used for evaluation of white matter microstructural integrity, identification of white matter tracts. CISS, axial + MPR imaging for evaluation of cerebellar folia, cranial nerves, ventricles, and foramina. Susceptibility weighted axial scan for Identification and characterization of hemorrhage, blood products, calcification, and iron accumulation.

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.

Electroencephalography (EEG) in one patient showed epileptiformic activities in the frontal and frontotemporal areas as well as increased spike waves while the patient was sleeping. Another patient's EEG showed occipital rhythms in background activity that was abnormal, focal discharges over the temporal lobe, and multifocial epileptiform activity. Several patients showed a loss of normal background activity.

Most patients begin to use a wheelchair for movement around age 30-40. Death usually occurs in their 60s, but some have been reported to live longer.

The diagnostic work up usually includes and MRI of the brain, an EEG, ophthalmic examination and a cardiac ECHO.

Muscle biopsy - which is not commonly done - may show storage of abnormal material and secondary mitochondrial abnormalities in skeletal muscle. Other features that may be seen on muscle biopsy include variability in fibre size, increase in internal and centralized nuclei, type 1 fibre hypotrophy with normally sized type 2 fibres, increased glycogen storage and variable vacuoles on light microscopy

The diagnosis is confirmed by sequencing of the EPG5.