Whole exome sequencing in Serbian patients with hereditary spastic paraplegia.

Hereditary spastic paraplegia (HSP) is a group of neurodegenerative diseases with a high genetic and clinical heterogeneity. Numerous HSP patients remain genetically undiagnosed despite screening for known genetic causes of HSP. Therefore, identification of novel variants and genes is needed. Our previous study analyzed 74 adult Serbian HSP patients from 65 families using panel of the 13 most common HSP genes in combination with a copy number variation analysis. Conclusive genetic findings were established in 23 patients from 19 families (29%). In the present study, nine patients from nine families previously negative on the HSP gene panel were selected for the whole exome sequencing (WES). Further, 44 newly diagnosed adult HSP patients from 44 families were sent to WES directly, since many studies showed WES may be used as the first step in HSP diagnosis. WES analysis of cohort 1 revealed a likely genetic cause in five (56%) of nine HSP families, including variants in the ETHE1, ZFYVE26, RNF170, CAPN1, and WASHC5 genes. In cohort 2, possible causative variants were found in seven (16%) of 44 patients (later updated to 27% when other diagnosis were excluded), comprising six different genes: SPAST, SPG11, WASCH5, KIF1A, KIF5A, and ABCD1. These results expand the genetic spectrum of HSP patients in Serbia and the region with implications for molecular genetic diagnosis and future causative therapies. Wide HSP panel can be the first step in diagnosis, alongside with the copy number variation (CNV) analysis, while WES should be performed after.

Clinical score for early diagnosis of myotonic dystrophy type 2.

INTRODUCTION: Myotonic dystrophy type 2 (DM2) is a rare, multisystemic, autosomal dominant disease with highly variable clinical presentation. DM2 is considered to be highly underdiagnosed. OBJECTIVE: The aim of this study was to determine which symptoms, signs, and diagnostic findings in patients referred to neurological outpatient units are the most indicative to arouse suspicion of DM2. We tried to make a useful and easy-to-administer clinical scoring system for early diagnosis of DM2-DM2 early diagnosis score (DM2-EDS). PATIENTS AND METHODS: Two hundred ninety-one patients with a clinical suspicion of DM2 were included: 69 were genetically confirmed to have DM2, and 222 patients were DM2 negative. Relevant history, neurological, and paraclinical data were obtained from the electronic medical records. RESULTS: The following parameters appeared as significant predictors of DM2 diagnosis: cataracts (beta = 0.410, p < 0.001), myotonia on needle EMG (beta = 0.298, p < 0.001), hand tremor (beta = 0.211, p = 0.001), positive family history (beta = 0.171, p = 0.012), and calf hypertrophy (beta = 0.120, p = 0.043). In the final DM2-EDS, based on the beta values, symptoms were associated with the following values: cataracts (present 3.4, absent 0), myotonia (present 2.5, absent 0), tremor (present 1.7, absent 0), family history (positive 1.4, negative 0), and calf hypertrophy (present 1.0, absent 0). A cut-off value on DM2-EDS of 3.25 of maximum 10 points had a sensitivity of 84% and specificity of 81% to diagnose DM2. CONCLUSION: Significant predictors of DM2 diagnosis in the neurology outpatient unit were identified. We made an easy-to-administer DM2-EDS score for early diagnosis of DM2.

Autoimmune Diseases in Patients With Myotonic Dystrophy Type 2.

Introduction: Myotonic dystrophy type 2 (DM2) is a rare autosomal dominant multisystemic disease with highly variable clinical presentation. Several case reports and one cohort study suggested a significant association between DM2 and autoimmune diseases (AIDs). Aim: The aim of this study is to analyze the frequency and type of AIDs in patients with DM2 from the Serbian DM registry. Patients and Methods: A total of 131 patients with DM2 from 108 families were included, [62.6% women, mean age at DM2 onset 40.4 (with standard deviation 13) years, age at entering the registry 52 (12.8) years, and age at analysis 58.4 (12.8) years]. Data were obtained from Akhenaten, the Serbian registry for DM, and through the hospital electronic data system. Results: Upon entering the registry, 35 (26.7%) of the 131 patients with DM2 had AIDs including Hashimoto thyroiditis (18.1%), rheumatoid arthritis, diabetes mellitus type 1, systemic lupus, Sjogren's disease, localized scleroderma, psoriasis, celiac disease, Graves's disease, neuromyelitis optica, myasthenia gravis, and Guillain-Barre syndrome. At the time of data analysis, one additional patient developed new AIDs, so eventually, 36 (28.8%) of 125 DM2 survivors had AIDs. Antinuclear antibodies (ANAs) were found in 14 (10.7%) of 63 tested patients, including 12 without defined corresponding AID (all in low titers, 1:40 to 1:160). Antineutrophil cytoplasmic antibodies (ANCAs) were negative in all 50 tested cases. The percentage of women was significantly higher among patients with AIDs (82.9% vs. 55.2%, p <0.01). Conclusion: AIDs were present in as high as 30% of the patients with DM2. Thus, screening for AIDs in DM2 seems reasonable. Presence of AIDs and/or ANAs may lead to under-diagnosis of DM2.

Cognitive assessment in patients with myotonic dystrophy type 2.

Myotonic dystrophy type 2 (DM2) is an autosomal dominant multisystemic disorder. Previous studies conducted on small cohorts of DM2 patients indicated presence of a cognitive dysfunction. We aimed to assess cognitive functions in a larger cohort of Serbian DM2 patients using an extensive battery of neuropsychological tests. The study included 76 patients with a genetically confirmed DM2, 68 of whom had all tests for different cognitive domains performed. Patients underwent clinical and neuropsychological testing, including cognitive screening and assessment of general intellectual level, attention, executive and visuospatial abilities, memory, and language functions. Only 6% of patients achieved a below-average score on the general intellectual level test. Cognitive screening tests indicated presence of cognitive deficits in 5.5% of patients according to the Mini Mental State Examination test and 25.8% according to the Addenbrooke's Cognitive Examination Revised test. Twenty-four (35.3%) patients had a cognitive impairment (being two standard deviations out of norm in at least two cognitive domains). Around one quarter of DM2 patients had a significant cognitive impairment that interfered with their everyday functioning. Patients with significant cognitive impairment were older at testing and at disease onset, less educated, and had more severe muscle weakness.

Physical and Mental Aspects of Quality of Life in Patients With Charcot-Marie-Tooth Disease Type 1A.

Introduction: Charcot-Marie-Tooth type 1A (CMT1A) comprises ~50% of all CMT cases. CMT1A is a slowly progressive motor and sensory neuropathy that leads to significant disability. We aimed to investigate the quality of life (QoL) in Serbian patients with CMT1A and to assess sociodemographic and clinical features associated with their QoL. Material and Methods: Forty-five genetically confirmed patients with CMT1A were included -60% women [age 50.4 ± 12.6 years, disease duration 22 (12.5-31.5) years]. SF-36, Medical Research Council (MRC) Sum Score, CMT Examination Score (CMTES), Overall Neuropathy Limitation Scale (ONLS), Beck Depression Inventory (BDI), and Krupp's Fatigue Severity Scale (FSS) were used in the study. Results: Regarding SF-36, Mental Health and Social Functioning were the scales with the best achievements, whereas Role Physical was the worst domain. Worse QoL in patients with CMT1A was associated with elder age (rho = -0.34, p < 0.05), longer disease duration (rho = -0.31, p < 0.05), more pronounced muscle weakness measured by MRC-SS (rho = 0.43, p < 0.01), presence of tremor (p < 0.05), worse CMTES (rho = -0.68, p < 0.01), more severe disability in upper (rho = -0.70, p < 0.01) and lower limbs (rho = -0.61, p < 0.01) measured by ONLS scores, use of walking aids (p < 0.01), and with depression (p < 0.01) and fatigue (p < 0.01). Worse scores on CMTES (beta = -0.43, p < 0.01), BDI (beta = -0.39, p < 0.01), and FSS (beta = -0.36, p < 0.01) were significant independent predictors of worse QoL in patients with CMT1A (adjusted R 2 = 0.77, p < 0.001). Conclusion: Besides impairment made directly by CMT1A itself, QoL in these patients was also strongly affected by the presence of depression and fatigue. Since CMT1A is still not a curable disease, it is of interest to identify factors associated with QoL that are amenable to treatment.

Long-term outcome in patients with myasthenia gravis: one decade longitudinal study.

INTRODUCTION: Even treated, myasthenia gravis (MG) continues to represent a significant burden and might continuously affect patients' quality of life (QoL). The aim of our longitudinal study was to analyze QoL in a large cohort of MG patients after a 10-year follow-up period. METHODS: This study comprised 78 MG patients (60% females, 50 ± 16 years old at baseline, 70% AchR positive) who were retested after 10 years. Disease severity was evaluated by MGFA classification. QoL was assessed using SF-36 questionnaire and Myasthenia Gravis-specific Questionnaire (MGQ). Hamilton rating scales for depression and anxiety (HDRS and HARS), Multidimensional Scale of Perceived Social Support (MSPSS) and Acceptance of Illness Scale (AIS) were also used. RESULTS: Similar percentage of patients was in remission at both time points (42% and 45%). However, at baseline all patients were treated, while 32% were treatment-free at follow-up. SF-36, MGQ, MSPSS and AIS scores were similar at baseline and retest. Mean HDRS and HARS scores worsened during time (p < 0.05), although percentage of patients with depression and anxiety did not change significantly. Significant predictors of worse SF-36 score at retest were depression (ß = - 0.45, p < 0.01), poor disease acceptance (ß = - 0.44, p < 0.01) and older age (ß = - 0.30, p < 0.01). Significant predictors of worse MGQ score at retest were poor disease acceptance (ß = - 0.40, p < 0.01), retirement (ß = - 0.36, p < 0.01), lower education (ß = 0.25, p < 0.01), and depression (ß = - 0.18, p < 0.05). CONCLUSIONS: Although after 10 years, a significant number of MG patients were in remission, their QoL was still reduced. Neurologists should be aware that patients' perception of poor QoL may persist even if MG is well treated from a physician's perspective.

Yield of the PMP22 deletion analysis in patients with compression neuropathies.

INTRODUCTION: Hereditary neuropathy with liability to pressure palsies (HNPP) is a rare neuromuscular disorder, mostly caused by PMP22 deletion. AIM: To determine a yield of the genetic analysis of PMP22 gene deletion in patients with compression neuropathies. METHOD: We included 112 patients with clinical suspicion of HNPP diagnosis. Nerve conduction studies (NCS) were performed for motor and sensory nerves bilaterally. Number of the PMP22 gene copies was determined using a real-time polymerase chain reaction (RT-PCR). RESULTS: PMP22 deletion was found in 34 (30.3%) patients. Patients with genetically confirmed HNPP had 12 years earlier disease onset compared to other patients with compression neuropathies (p < 0.01), more nerves affected during lifespan (5.5 ± 3.5 vs. 3.0 ± 2.0, p < 0.01) and at the time of referral (2.7 ± 2.5 vs. 2.0 ± 1.9, p < 0.05). HNPP patients had positive family history more frequently (p < 0.01). Foot deformities (pes cavus and hammertoe), symmetric muscle atrophy in lower legs and absent muscle reflexes in lower limbs were more common in HNPP patients. NCS abnormalities were also more common in HNPP group. Multiple linear regression analysis identified positive family history (ß = + 0.35, p < 0.01) and decreased sensory conduction velocity in at least three sensory nerves (ß = + 0.40, p < 0.01) as independent predictors of the PMP22 deletion. CONCLUSION: Among patients with compression neuropathies, those with a positive family history, earlier symptom onset and NCS abnormalities had a higher chance to have PMP22 deletion.

Neuropathic pain in patients with Charcot-Marie-Tooth type 1A.

BACKGROUND: Only several studies analyzed the characteristics of neuropathic pain (NeP) more extensively in patients with Charcot-Marie-Tooth type 1A (CMT1A). Therefore, we sought to determine the frequency and features of NeP in CMT1A patients and to assess the association between NeP and sociodemographic and clinical characteristics of patients with CMT1A. METHODS: Our research included 51 genetically diagnosed CMT1A patients. The International Association for the Study of Pain (IASP) criteria were used for diagnosis of NeP. PainDETECT questionnaire (PD-Q) was used to assess NeP features. The Medical Research Council (MRC) Sum Score, CMT Neuropathy Score (CMTNS), Overall Neuropathy Limitation Scale (ONLS) score, and Beck Depression Inventory were also used. RESULTS: NeP was present in 15 (29.4%) patients with CMT1A. The average intensity of pain was 5.7 ± 2.2 out of 10. The most sensitive neuropathic symptoms were numbness, then tingling, and burning sensations, while the most specific symptom was allodynia. Patients with NeP more frequently reported pain in the back (p < 0.01) and the trunk (p < 0.05). Patients with NeP had more pronounced disability of the upper extremities and overall disability, as assessed by the ONLS score (p < 0.05). Depression was more frequent in patients with NeP compared with patients without NeP (66.7 to 13.9%, p < 0.01). CONCLUSION: NeP was present in almost one-third of the patients with CMT1A and it was moderate on average. Presence of NeP was associated with worse functional disability and depression.