A variant of amaurotic idiocy, adult neuronal ceroid lipofuscinosis (Cuffs disease, CLN4), despite the name, debuts in childhood or in puberty; the first signs may manifest during the first three years. But in terms of its course, it is the mildest form of hereditary idiocy. You will learn about the peculiarities of the pathology, its diagnosis and correction from the article.
- What is Cuffs disease.
- Atypical forms.
What is Cuffs disease
Cuffs disease is an adult form of amaurotic idiocy that has the mildest course itself. The pathology deburs imperceptibly and manifests cognitive and behavioral abnormalities. As a result, mild dementia is formed. The longer the pathology exists, the more pronounced the extrapyramidal signs become, in particular facial dyskinesia. There are no problems with vision or hearing. Myoclonic seizures are possible in a few.
There are two types of the disease:
- With progressive myoclonic epilepsy.
- With neuropsychiatric disorders, dementia, motor, cerebellar and extrapyramidal disorders. The EEG records the reaction to photostimulation.
Most cases are sporadic, most probably autosomal recurrent, rarely dominant type of inheritance. Cytosomes with granulation as osmiophilic inclusions can be detected.
Atypia accounts for about 20% of all cases of pathology. There are 15 different classification groups, and there are less extensive gradations, but none is perfect. First of all, it is necessary to clarify whether atypical forms are independent nosologies. For example, the Norman-Wood type is characterized by the rapid development of fatal respiratory failure and epilepsy. It is believed.
That the trigger of the pathology is a deficiency of the lysosomal cathepsin D. The debut of the pathology is the appearance of ocular symptoms, dementia, and epileptic seizures. It is the nonlinear inclusions that become the distinguishing markers of this pathology from the adult form.
The pigmentary variant debuts in childhood, also demonstrates a long course, but is distinguished by visually accumulated inclusions. Both the infantile type of lysosomal pathology and cases of childhood pathology with chorea, spinocerebellar symptoms, neuropathy and slow disease progression have been described. There are several cases of pathological changes on the background of osteoporosis, which can progress from birth and even in the prenatal period.
Making a correct diagnosis of Cuffs syndrome can be difficult especially with atypical forms of the pathology. The electroretinogram, a characteristic EEG response to low-frequency light stimulation, helps. Atrophy of cerebral structures, which becomes visible on neuroimaging, usually manifests early, but not necessarily in the first year of the disease.
Minimization of the hypothalamic response, through which leptin is affiliated, is detectable in the adult form, late infancy, and is not specific for diagnosis. Molecular genetic testing by assessing palmitoyl-protein thioesterase content and tripeptyl-peptidase activity in adult forms of the pathology are considered the most effective diagnostic modalities.
Gene mutation analysis is possible in such forms of adult pathology for which a cloned gene exists. Methods for diagnosing rare forms of amaurotic idiocy are still being developed. Sometimes, imaging of characteristic inclusions in lymphocytes, skin, conjunctivae, or other tissues outside the nervous system remains the only diagnostic method available. No single type of inclusion can be considered specific to a particular form of idiocy, but there is usually a predominant type.
Biopsy results of tissues outside the nervous system can sometimes be negative. Sometimes a biopsy of the rectum can show neurons with pathological inclusions. Prenatal diagnosis of forms where a particular gene has already been identified is performed on the basis of the same molecular technologies. Morphological evaluation of inclusions in amniotic fluid or biopsy specimens of chorionic villi is also possible. One should not forget about mitochondrial ATPase in adult forms of the pathology in combination with DNA fusion. Carriers can be identified in individual cases of Cufs disease.
There are no pathogenetic methods. Today, it is practiced to correct the symptomatology in the adult version of amaurotic idiocy by antioxidants and vitamin-mineral complexes. Despite the mildness of the symptoms, such treatment does not give sufficient results. In many cases, when the seizure syndrome is pronounced or epileptic seizures are present, anticonvulsants are used. Valproate sodium, Clonazepam are effective. However, anticonvulsants must be chosen individually, taking into account that seizures can be completely refractory. Patients need supportive care to cope with a severe illness.
In Cuffs disease, the prognosis is most favorable because of the mild course of the pathology.