Clinical Neuroscience

Mid-term oral isotretinoin therapy causes a predominantly sensory demyelinating neuropathy

ALTUN Yasar1, INAN Esra2

MAY 30, 2019

Clinical Neuroscience - 2019;72(05-06)


Aim - The purpose of this prospective study was to investigate whether mid-term treatment with oral isotretinoin may impact peripheral nerve function. Methods - In this study, we included 28 patients with no apparent neurological or neurophysiological findings. The patients received treatment with oral isotretinoin for papulopustular or nodulocystic acne. The patients with normal findings in the first examination were given 1 mg/kg/day oral isotretinoin. Neurological examinations and electroneurographic studies were performed before and 6 months after the onset of isotretinoin treatment. Results - Clinical examinations and electroneurographic evaluations prior to treatment revealed no abnormalities in any of the patients. However, 20 patients (72%) displayed one or more abnormal values in the tested parameters after treatment. Although the mean amplitudes of compound muscle action potential of the ulnar and median nerves did not vary, significant decreases were observed in the mean sensory conduction velocities of median, ulnar, sural, medial plantar, medial dorsal cutaneous, and dorsal sural nerves 6 months after the onset of treatment. Conclusion - Systemic use of isotretinoin may cause electroneurographic changes. Probable electroneurographic alterations may be detected at a much earlier period via dorsal sural nerve tracing when electrophysiological methods used in routine clinical practice cannot detect these changes.


  1. Department of Neurology, Medical Faculty of Adiyaman University, Adiyaman, Turkey
  2. Department of Dermatology, Medical Faculty of Adiyaman University, Adiyaman, Turkey



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Clinical Neuroscience

The prevalence of sarcopenia and dynapenia according to stage among Alzheimer-type dementia patients

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Aim - In this study, the aim was to identify the prevalence of sarcopenia and dynapenia according to disease stage among Alzheimer-type dementia (AD) patients and collect data to suggest precautions related to reducing the disease load. Method - The study was completed with 127 patients separated into stages according to Clinical Dementia Rating Scale (CDR) criteria and 279 healthy volunteers aged 18-39 years and 70-80 years abiding by the exclusion criteria who agreed to participate in the research. Our prospective and cross-sectional study applied the CDR and mini mental test (MMSE) to patients with disorder in more than one cognitive area and possible AD diagnosis according to NINCDS-ADRDA (National Institute of Neurological and Communicative Disorders and Stroke-Alzheimer’s Disease and Related Disorders Association) diagnostic criteria. The patient and control groups had skeletal muscle mass index (SMMI), muscle strength and physical performance assessed with sarcopenia diagnosis according to European Working Group on Sarcopenia in Older People (EWGSOP) diagnostic criteria. Results - In our study, in parallel with the increase in disease stage of AD patients, the prevalence of sarcopenia (led by severe sarcopenia) and dynapenia was higher compared to a control group of similar age. Conclusion - In chronic, progressive diseases, like AD, identification of changes in parameters, like muscle mass and strength and reductions in physical performance in the early period, is important for identification and to take precautions in the initial stages considering the limitations of the preventive effects of treatment applied after diagnosis of AD.

Clinical Neuroscience

Hyperhomocysteinemia in female migraineurs of childbearing ages


Background and purpose - Migraine is a risk factor for ischemic stroke in women of childbearing ages. Previous researches revealed a higher prevalence of hyperhomocysteinemia in migraineurs. Possible differences on the frequencies of hyperhomocysteinemia between migraine with aura and migraine without aura could contribute the established variances in stroke risk between these migraine types. Therefore, we aimed to search if the frequency of hyperhomocysteinemia was different between these subtypes of migraine or not. Methods - We analyzed the findings of serum homocysteine levels in female migraineurs of 16-49 years old who admitted to our outpatient clinic. Results - Homocysteine level was elevated in 13.3% of study population. There were not any significant differences on median serum homocysteine levels between migraine with aura (8.0 mikromol/L) and without aura (8.5 mikromol/L). (p=0.426) The frequencies of hyperhomocysteinemia were also similar (9.1% versus 16.7%, respectively; p=0.373). Correlation analyses did not reveal any linear correlation between ages and homocysteine levels either in group of migraine with aura or in group of migraine without aura (p=0.417 and p=0.647, respectively). Similarly, any linear correlation between disease ages and homocysteine levels either in group of migraine with aura or in group of migraine without aura was not detected (p=0.359 and p=0.849, respectively). Conclusion - The median serum homocysteine levels and the frequencies of hyperhomocysteinemia are similar between migraine with aura and without aura in women of childbearing ages. Therefore, the variances on stroke risk ratios between these types of migraine are probably not originated from the differences of serum homocysteine status.

Clinical Neuroscience

The methylation status of NKCC1 and KCC2 in the patients with refractory temporal lobe epilepsy

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Purpose - Methylation is a key epigenetic modification of DNA and regarding its impact on epilepsy, it is argued that “DNA methylation may play an important role in seizure susceptibility and maintenance of the disorder”. DNA methylation status of KCC2 (SCL12A5) and NKCC1 (SCL12A2) associated with refractory temporal lobe epilepsy was investigated in our study. Materials and methods - Thirty-eight patients with temporal lobe epilepsy (TLE) who were diagnosed by video EEG monitoring and 32 healthy control subjects were included in the study. Twenty-three patients in TLE group were men and the remaining 15 were women. Among them, 27 had unilateral temporal focus (9 with right; 18 with left) and 11 patients had bilateral TLE. We analyzed promoter region methylation status of the KCC2 (SCL12A5) and NKCC1 (SCL12A2) genes in the case and control groups. Gene regions of interest were amplified through PCR and sequencing was accomplished with pyro-sequencing. Results - We found a significant relationship between TLE and methylation on the NKCC1. However, there was no association between TLE and methylation on the KCC2 gene. Also, we found no association between right or left and unilateral or bilateral foci of TLE. There was no relationship between TLE and methylation on the NKCC1and KCC2 genes in terms of mesial temporal sclerosis in cranial MRI, head trauma or febrile convulsions. Conclusion - The methylation of NKCC1 can be a mecha­nism of refractory temporal lobe epilepsy. There are limited findings about DNA methylation in TLE. Therefore, further studies with large sample sizes are necessary.

Clinical Neuroscience

[F-DOPA PET/MR based target definiton in the 3D based radiotherapy treatment of glioblastoma multiforme patients. First Hungarian experiences ]

SIPOS Dávid, TÓTH Zoltán, LUKÁCS Gábor, BAJZIK Gábor, HADJIEV Janaki, CSELIK Zsolt, REPA Imre, KOVÁCS Árpád

[Introduction - Radiotherapy plays important role in the complex oncological treatment of glioblastoma multiforme (GBM). The modern 3D radiotherapy treatments are based on cross-sectional CT and MR information, however more attention is being paid to functional hybrid imaging describing the biological and functional morphology of tumor lesions. 18F-DOPA is an amino acid tracer with high specificity and sensitivity, which may play an important role in the precise definition of target volume in the irradiation process of GBM patients. Our study presents the first experiences with 18F-DOPA based PET/CT/MR 3D irradiation planning process. Methods - In Hungary the 18F-DOPA radiotracer has been available for clinical use since September 2017. Between September 2017 and January 2018, at the Somogy County Kaposi Mór Teaching Hospital Dr. József Baka Diagnostic, Radiation Oncology, Research and Teaching Center 3 histologically verified glioblastoma multiforme patients received 18F-DOPA based 3D irradiation treatment. In the contouring process the native planning CT scanes were fused with the PET/MR series (T1 contrast enhanced, T2 and 18F-DOPA sequences). We defined 18F-DOPA uptake volume (BTV-F-DOPA), the T1 contrast enhanced MRI volume (GTV-T1CE), and the volume of the area covered by oedema on the T2 weighted MRI scan (CTV-oedema) in all patients. We also registered the BTV-F-DOPA volumes not covered by the conventional MR based target volumes. Results - Examining the 3 cases, the average volume of 18F-DOPA tumor was 22.7 cm3 (range 15.3-30.9; SD = 7.82). The average GTV T1 CE was found to be 8.7 cm3 (range 3.8-13.2; SD = 4.70). The mean CTV oedema volume was 40.3 cm3 (range 27.7-57.7; SD = 15.36). A non-overlapping target volume difference (BTV-F-DOPA not covered by CTV oedema area) was 4.5 cm3 (range 1-10.3; SD = 5.05) for PTV definition. Conclusion - Based on our results the tumor area defined by the amino acid tracer is not fully identical with the MRI defined T2 oedema CTV. 18F-DOPA defined BTV can modify the definiton of the PTV, and the radiotherapy treatment. ]

Clinical Neuroscience

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Clinical Neuroscience

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Clinical Neuroscience

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Clinical Neuroscience

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