Neurological assessment and nerve conduction study findings in 22 patients with alkaptonuria from Jordan

Abstract

Alkaptonuria is a rare metabolic disease characterised by accumulative deposition of homogentisic acid in the connective tissue of the body. This results in early degeneration of tendons, cartilages, heart valves, and other tissues. The main objective of the study is to examine the possibility of the nervous system involvement in patients with alkaptonuria The sample consists of two groups; 22 patients with AKU and 20 controls. A neurological assessment has been carried out including detailed medical history, neurological examination, and a nerve conduction study of the nerves of the dominant hand. The prevalence of any abnormality was compared between the two groups using chi square test. The mean values of the nerve conduction study were compared between the two groups using student t-test. There was a higher prevalence of low back pain, hearing problems and tinnitus, numbness and neuropathic pain in alkaptonuria patients. There was no significant difference between the two groups in other conditions such as seizures, headache, and syncope. The values of the nerve conduction study did not show significant difference between the two groups. Neurologically related symptoms in alkaptonuria mostly represent complications of the connective tissue degeneration rather than direct involvement of the nervous system. This has been supported further by the normal findings of the neurophysiology study in patients with alkaptonuria.

Successful treatment of attention-deficit/hyperactivity disorder accompanying to alkaptonuria with methylphenidate and risperidone

“…The prevalence of symptoms such as loss of consciousness or seizures that may indicate the direct involvement of nervous system was comparable in AKU patients while the prevalence of symptoms such as low back pain, neuropathic pain, tinnitus, or hearing loss that may not indicate direct neuronal involvement was higher in AKU patients than the general population. In addition, it was shown that peripheral nerve conduction was preserved [23]. It was also known that there is an association between Parkinson disease and AKU [24].…”

Acute-Onset Multifocal Hand Dysfunction Due to Alkaptonuria

“…A statistically significant greater prevalence of extremity numbness, weakness, and neuropathic pain; tinnitus and hearing problems; visual blurring; and tremors were demonstrated in patients with alkaptonuria when compared with healthy controls. 4 Significant differences in neurophysiologic studies between patients with alkaptonuria and controls have not been shown, and peripheral neurologic symptoms are thus likely to be a result of vertebral degeneration and foraminal stenosis. However, a single case with severe generalized polyneuropathy of both axonal and demyelinating types has been described.…”

“…However, a single case with severe generalized polyneuropathy of both axonal and demyelinating types has been described. 4 Central symptoms such as ocular or aural dysfunction may be related to the deposition of material into and distortion of connective tissues, such as the tympanic membrane and orbital musculature.…”