Neurocognitive Impairment in Patients With Ataxia Telangiectasia and Their Unaffected Parents: Is It Similar?

BACKGROUND: Ataxia telangiectasia (AT) is a genetic multisystemic disorder affecting the nervous system. Data on neurocognitive functioning in AT are limited and focused on patients at various stages of disease. Because of the genetic nature of the disorder, parents of patients may also display subtle neurological problems. This study aimed to evaluate neurocognitive functioning in patients with AT and their unaffected parents. METHODS: The study included 26 patients with AT and 41 parents among which 13 patients and 18 parents were evaluated with neurocognitive tests. Clinical and radiological data were reviewed retrospectively. Data were analyzed with descriptive statistics. RESULTS: The median ages of patients and parents were 12.5 years (interquartile range [IQR] = 9.5) and 38.0 years (IQR = 12.0), respectively. Median intelligence quotients were 62.0 (IQR = 21.3) and 82.5 (IQR = 16.8), respectively, for patients and parents. Rates of intellectual disability for patients and parents were 100.0% and 83.3%, respectively. Areas of impairment in patients in decreasing order of frequency were motor skills, visual perception/memory, visual-manual coordination, spontaneous/focused and sustained attention (100.0% for each), social judgment, as well as vocabulary and arithmetic skills (75.0% for each). Areas of impairment in unaffected parents in decreasing order of frequency were visual-manual coordination (77.8%), working memory (76.5%), and visual perception and motor skills (66.7% for each). CONCLUSION: Intellectual disabilities, visual-spatial disabilities, and reduced visual-motor coordination seem to be similar in patients with AT and their parents. These results should be replicated with larger samples from multiple centers and may form putative cognitive endophenotypes for the disorder.

Corneal nerve fiber involvement in chronic inflammatory demyelinating polyneuropathy.

BACKGROUND: Despite the primary myelin-related pathophysiology, small fiber neuropathy (SFN) and axonal degeneration are also considered to be involved and associated with disabling symptoms and impaired quality of life in chronic inflammatory demyelinating polyneuropathy (CIDP). Demonstration of SFN usually requires complex or invasive investigations. OBJECTS: In vivo corneal confocal microscopy (IVCCM) has evolved as a non-invasive, easily applied method for quantification of small fiber involvement in peripheral nerve disorders. We aimed to investigate the potential role of IVCCM in CIDP. METHODS: In this cross-sectional study, 15 patients with CIDP underwent assessment with clinical disability scales, neuropathic pain (NP) and autonomic symptom questionnaires, nerve conduction studies, and IVCCM. IVCCM parameters were analyzed and compared to those from 32 healthy controls. RESULTS: Corneal nerve fiber density (CNFD) and corneal nerve fiber length (CNFL) were significantly decreased in the CIDP group, compared to those in controls (p = 0.03 and p = 0.024, respectively). Langerhans cells and fiber tortuosity were increased in CIDP patients (p = 0.005 and p = 0.001, respectively). IVCCM parameters were significantly lower in patients with NP compared to those in patients without NP. CONCLUSION: IVCCM shows promise as a non-invasive complementary biomarker in the assessment of demyelinating polyneuropathies, providing insights into the potential pathophysiology of these non-length-dependent neuropathies.

Impact of obstructive sleep apnea on neuromuscular transmission- a descriptive study.

Objective: Obstructive sleep apnea (OSA) is a sleep disorder accompanied by intermittent hypoxia. Neuromuscular transmission (NT) is known to be disturbed under chronic hypoxia. In this descriptive study, it has been aimed to test NT under intermittent hypoxia in OSA. Methods: Thirty-nine newly diagnosed OSA patients without any comorbidities or conditions that alter NT were included in the study. Jitter analysis was performed using a concentric needle electrode. Results: The mean jitter value of 39 OSA patients was 25.9 ± 3.7 µs. When compared to the mean reference jitter values, patients in the present study had significantly higher jitter (p < 0.001). Seven (17.9%) patients met the electrophysiological criteria for NT failure. Conclusion: The authors propose that intermittent hypoxia can be the trigger for NT failure in OSA. The interaction between increased oxidative stress and disturbed mitochondrial functions may also contribute.

Cutaneous silent period in myofascial pain syndrome.

INTRODUCTION: An increased response to painful stimuli without spontaneous pain suggests a role of central hyperexcitability of pain pathways in the pathogenesis of myofascial pain syndrome (MPS). In this study we aimed to test the hypothesis that spinal pain pathways are affected in MPS. We used cutaneous silent period (CSP) parameters to demonstrate the hyperexcitability of spinal pain pathways in MPS. METHODS: Twenty-nine patients diagnosed with MPS and 30 healthy volunteers were included in the study. The CSP recordings were performed in the right upper and left lower extremities. RESULTS: In both upper and lower extremities, patients had prolonged CSP latencies (P = 0.034 and P = 0.049 respectively) and shortened CSP durations (P = 0.009 and P = 0.008, respectively). DISCUSSION: Delayed and shortened CSP in MPS patients implies dysfunction in the inhibitory mechanism of the spinal/supraspinal pain pathways, suggesting central sensitization in the pathogenesis of MPS and supporting our research hypothesis. Muscle Nerve 57: E24-E28, 2018.

Executive functions in sarcoidosis: a neurocognitive assessment study.

Background: Sarcoidosis is a multisystem, inflammatory disease characterized by non-caseating granulomas in multiple organs. Neuropsychological impairment has been told to be present in about 10% of sarcoidosis patients with diagnosed central nervous system (CNS) involvement. Both anatomical lesions and changes in immunological parameters in sarcoidosis may cause cognitive impairment. Based on the information that soluble interleukin-2 receptors (sIL-2R) and tumour necrosis factor alpha (TNF-‱) which plays a role in the pathogenesis of sarcoidosis accumulate in the basal ganglia and prefrontal structures, impairment in executive functioning is most likely to be expected in sarcoidosis. In this study we aimed to evaluate executive functions in sarcoidosis patients. Method: This study included 21 sarcoidosis patients (14 females, 7 males) and 21 healthy controls (12 females, 9 males). All participants were given Beck Depression Inventory-Second Edition, Stroop Test, Verbal Fluency Tests, Digitspan Forward Test, Digitspan Backwards Test and Trail Making Test Part-B. Test results of sarcoidosis patients were compared with healthy controls. Results: No significant difference was detected between sarcoidosis patients and healthy controls by means of neuropsychological assessment tests (p>0.05). Conclusion: Our study showed that sarcoidosis patients did not have impairment in executive functions. This result may be commented in two different outcomes. One of them, would be the probable necessity of additional electrophysiological or radiological tests including detailed paradigmas for evaluation of executive functions. Secondly the effect of therapeutics used in sarcoidosis (steroids and/or immunosuppressants) on cognition should be questioned regarding the controversial previous data which released cognitive decline in sarcoidosis. (Sarcoidosis Vasc Diffuse Lung Dis 2018; 35: 26-34).

Medial plantar-to-radial amplitude ratio: does it have electrodiagnostic utility in distal sensory polyneuropathy?

PURPOSE OF THE STUDY: We proposed a new electrophysiological parameter medial plantar (MP)-to-radial amplitude ratio (MPRAR), similar to sural-to-radial amplitude ratio (SRAR), in the diagnosis of distal sensory polyneuropathy (DSP), based on the concept that distal nerves are affected more and earlier than proximal nerves in axonal neuropathies. We aimed to investigate the diagnostic sensitivity of this parameter in diabetic DSP, together with sensitivities of SRAR and MP nerve action potential (NAP) amplitude. MATERIALS AND METHODS: In 124 healthy controls and 87 diabetic patients with clinically defined DSP and normal sural responses, we prospectively performed sensory nerve conduction studies (NCS), and evaluated the MP NAP amplitude, MPRAR and SRAR values. We determined the lower limits of normal (LLN) of these parameters in the healthy controls and calculated their sensitivities and specificities in detecting DSP in diabetic patients. RESULTS: MP nerve amplitude and MPRAR values were significantly lower in the patient group, compared to controls. However, SRAR values did not differ significantly between the two groups. The LLN of MP NAP amplitude was found to be 4.1 µV. The cutoff values for SRAR and MPRAR were determined as 0.24 and 0.16, respectively. MPRAR was abnormal in 21.8% of patients. However, the most sensitive parameter in detection of DSP was MP NAP amplitude, which showed a sensitivity of 31% and a specificity of 100%. CONCLUSIONS: Although MPRAR is more sensitive than SRAR in detecting DSP, it does not provide additional diagnostic yield to the assessment of MP NCS alone in diabetic DSP patients with normal sural responses.

Executive functions in sarcoidosis: a neurocognitive assessment study.

Not available.