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.

Earlier age of symptom onset in younger generation of familial cases of multiple sclerosis.

AIM: The aim of this study was to assess the prevalence of familial MS (fMS) in Belgrade MS population, discern the differences between the persons with fMS and sporadic MS, and to detect the presence of anticipation phenomenon in fMS patients. METHODS: The data on the demographic and clinical characteristics of MS patients was obtained from the Belgrade MS population Registry. In cases of vertical transmission of MS, the family members were divided into the younger and older generation, in order to assess the potential presence of anticipation phenomenon. To adjust for follow-up time bias, a secondary analysis including only patients who had the onset of symptoms before 39 years (75.percentile), and those who were 39 + years, was performed. RESULTS: The prevalence of fMS in Belgrade MS population is 6.4%. FMS cases had earlier age at MS symptom onset (30.4 vs. 32.3 years) compared to sporadic MS cohort. When comparing fMS cases across generations, the younger generation had significantly lower age at onset compared with the older one (25.8 vs. 35.7 years, p < 0.001). After adjustment for the different length of the follow-up, the difference in age at symptom onset between the groups was reduced, but it still existed and was statistically significant (30.0 years in younger vs. 36.4 years in older generation, p = 0.040). CONCLUSION: In our study, the analysis of fMS cases across generations, showed an earlier age of symptom onset in the younger generation, even after adjustment. These results indicate the possibility of existence of anticipation phenomenon.

Impact of comorbidities on the disability progression in multiple sclerosis.

OBJECTIVES: Investigation of the comorbidity burden in persons with multiple sclerosis (PwMS) has become increasingly important. The aim of this study was to investigate the relationships of cardiovascular disease (CVD) comorbidities and type 2 diabetes with the disability progression. MATERIALS & METHODS: The retrospective cohort study was conducted at the Clinic of Neurology, Belgrade. The Belgrade MS population Registry, which comprises 2725 active MS cases, was used as the source of data. The mean duration of the disease was 21.6 ± 12.5 years. Expanded Disability Status Scale (EDSS) was followed in all PwMS in the Registry. In the statistical analysis, the Cox proportional hazard regression analysis and Kaplan-Meier curve were performed. RESULTS: Hypertension statistically significantly contributed to more rapid reaching investigated levels of irreversible disability (EDSS 4.0, 6.0, and 7.0), while the presence of any of the investigated CVD comorbidities and type 2 diabetes significantly contributed to faster reaching EDSS 4.0 and EDSS 6.0. In a multivariable model, progression index (PI) was singled out (HR = 3.171, p < .001), indicating that higher progression index (PI) was an independent predictor of CVD occurrence in MS patients. In the case of type 2 diabetes, PI (p < .001) and MS phenotype (p = .015) were statistically significant in multivariable Cox regression analysis. CONCLUSIONS: Our study confirms the impact of CVD comorbidities and type 2 diabetes in MS on the progression of disability as measured by EDSS in the large cohort of PwMS from the population Registry.

Occurrence of malignant diseases in patients with multiple sclerosis: population-based MS Registry data.

INTRODUCTION: Among different comorbidities occurring in multiple sclerosis (MS), the presence of malignant diseases in these patients is of the particular importance. The aim of this study was to determine the malignant diseases burden in a whole cohort of patients with MS in the Belgrade region, based on the Belgrade population registry data. MATERIAL AND METHODS: This study comprises 2725 MS patients from the MS Registry, which represents a source for all necessary demographic and clinical data. Firstly, the Registry was searched for all persons with MS who had cancer comorbidity, during the period 1996-2019. Diagnosis of cancer was validated by the patients' medical documentation. In order to investigate factors associated with the occurrence of any type of the cancer and/ or breast cancer only, in persons with MS, different logistic regression analyses were performed. RESULTS: A total of 64 persons with 69 malignant diseases were observed (prevalence 2.53%). The most frequent malignancies in males were skin cancer (50.0%) and in females, breast cancer (23.2%). The cumulative incidence of cancer comorbidity in persons with MS was 324.9 new cases per 100,000 person-years for the total population (137.6/100,000 in males and 403.6 per 100,000 in females). Comparison of cancer incidence rate between MS and general Belgrade population revealed lower risk for malignancy occurrence in the MS population in total (standardized incidence ratio, SIR = 0.58, 95% CI 0.16-1.49). CONCLUSIONS: Our findings demonstrate that MS patients in the Belgrade region have lower risk for the development of malignancy than age- and sex-matched general population.

The prevalence of comorbidities in patients with multiple sclerosis: population-based registry data.

BACKGROUND: Comorbidities occur frequently in persons with multiple sclerosis (MS). The aim of the present study was to determine the prevalence of the most common comorbidities in the population of MS patients in Belgrade, Serbia. MATERIAL AND METHODS: Data on diagnosed and fully documented comorbidities were taken from the Belgrade MS population registry. The list of explored comorbidities included cardiovascular, malignant, and autoimmune diseases; psychiatric disorders; epilepsy; and type 2 diabetes. In the data analysis, crude, age- and gender-specific, and age-adjusted prevalence was calculated. Additionally, comorbidities were analyzed in patients with various MS phenotypes. RESULTS: The most prevalent group of comorbidities were psychiatric (prevalence (Prev) = 20.59%, 95% CI 19.10-22.17) and cardiovascular comorbidities (Prev = 15.23%, 95% CI 13.93-16.63). The most prevalent single comorbidities were depression (Prev = 11.82%, 95% CI 10.64-13.11) and hypertension (Prev = 11.41%, 95% CI 10.25-12.68). Type 2 diabetes was significantly more prevalent in patients with primary progressive MS compared with the patients with relapsing-remitting and secondary progressive MS (p < 0.001). We found statistically significant positive correlation between number of comorbidities and progression index (p < 0.001). Patients treated with disease-modifying therapies (DMTs) had significantly higher risk of developing comorbidity, after treatment initiation, compared with those who were untreated (p = 0.001). CONCLUSIONS: Our study demonstrated high prevalence of comorbidities in persons with MS, with psychiatric and cardiovascular diseases being the most common. Furthermore, our findings confirmed the association of comorbidities with progression of disability and emphasized their role in treatment decision-making in MS.

Baseline characteristic of patients presenting with lacunar stroke and cerebral small vessel disease may predict future development of depression.

OBJECTIVE: Cerebral small vessel disease (SVD) is associated with late-onset depression and increases the risk for depression after stroke. We aimed to investigate baseline predictors of depression after long-term follow-up in patients with SVD, initially presenting with first-ever lacunar stroke, free of depression and cognitive impairment. METHODS: A total of 294 patients with SVD were evaluated 3-5 years after the qualifying event. We analyzed baseline demographic data, vascular risk factors, functional status expressed as a score on modified Rankin Scale (mRS), cognitive status, presence of depression, total number of lacunar infarcts and severity of white matter hyperintensities (WMH) on MRI with Age-Related White Matter Changes scale total score (tARWMC) and Fazekas scale periventricular and deep subcortical scores. RESULTS: On follow-up, depression was registered in 117 (39.8%) SVD patients. At the baseline, patients with depression compared with non-depressed were older (64.4 vs 60.9 years; p = 0.007), had higher mRS score (2.8 ± 0.7 vs 1.5 ± 0.7; p < 0.0001) and had more severe lesions on MRI scales (p < 0.0001 for all parameters). On follow-up, depressed patients more frequently exhibited cognitive decline (75.2% depressed vs 56.5% non-depressed; p = 0.003). No difference was detected in risk factor frequency between groups. Multivariate Cox regression analysis adjusted by age and gender revealed independent predictors of depression: baseline mRS >2 (HR 2.17, 95%CI 1.74-2.72; p < 0.0001) and tARWMC (HR 1.05, 95%CI 1.02-1.09; p = 0.005), and cognitive decline on follow-up (HR 1.80, 95%CI 1.12-2.89; p = 0.015). CONCLUSIONS: Baseline functional status and severity of WMH and development of cognitive decline predict the occurence of late-onset depression in patients with SVD.

Transcranial Parenchymal Sonographic Findings in Patients With Cerebral Small Vessel Disease: A Preliminary Study.

OBJECTIVES: Patients with cerebral small vessel disease often present with various motor, cognitive, and emotional changes, including gait disturbances, parkinsonism, and depression. Substantia nigra hyperechogenicity, brain stem raphe hypoechogenicity, ventricle diameters, and sonographic characteristics of other brain structures on transcranial sonography have been increasingly used as biomarkers in a range of neurologic diseases. We aimed to explore the frequency and clinical correlates of transcranial sonographic findings in symptomatic patients with small vessel disease. METHODS: In a cross-sectional study, neurologic, cognitive, and emotional statuses and transcranial sonographic and magnetic resonance imaging findings were compared between 102 patients with small vessel disease and 45 healthy age- and sex-matched control participants. RESULTS: Compared to healthy controls, small vessel disease cases had more frequent brain stem raphe hypoechogenicity (55.9% versus 11.1%; P < .0001), substantia nigra hyperechogenicity (30.4% versus 11.1%; P = .022), and enlarged third ventricles (P < .0001). Substantia nigra hyperechogenicity correlated with gait disturbances, extrapyramidal features, and cognitive impairment. Brain stem raphe hypoechogenicity was associated with the diagnosis of depression. Enlargement of the third and lateral ventricles was more frequent in patients with cognitive impairment. Pathologic substantia nigra hyperechogenicity and enlarged ventricles were associated with the severity of cerebral ischemic lesions. CONCLUSIONS: Transcranial sonography shows pathologic findings in a substantial number of patients with small vessel disease, probably reflecting disruption of frontostriatal pathways.

Altered basal ganglia echogenicity early in sporadic Creutzfeldt-Jakob disease.

Creutzfeldt-Jakob disease (CJD) is a fatal neurodegenerative disease caused by conformational alteration of the ubiquitous prion protein. Sporadic CJD appears to progress faster if the basal ganglia are shown to be affected on magnetic resonance imaging. Transcranial B-mode sonography (TCS) enables visualization of differences in tissue echogenicity, which can be associated with changes in the cerebral metabolism of various metals. These metabolic changes are considered 1 of the potential mechanisms of the brain damage in CJD; TCS hyperechogenicity may reflect changes in metal homeostasis in CJD. We report a 63-year-old woman who presented with typical sporadic CJD. One month after she fell ill, a magnetic resonance imaging scan of her brain showed diffuse cortical but no obvious basal ganglia involvement. However, TCS revealed moderate hyperechogenicity of both lentiform nuclei. The patient's disease progressed quickly and she died 2 months later. TCS may show basal ganglia alteration early in the disease course of patients with quickly progressing CJD, thus aiding in premortem diagnosis.

Exclusive breastfeeding may be a protective factor in individuals with familial multiple sclerosis. A population registry-based case-control study.

BACKGROUND: Multiple sclerosis (MS) is an immune-mediated disease that affects the central nervous system, which most likely results from the interplay between environmental and genetic factors. The aim of our study was to assess the effect of breastfeeding on the risk of developing familial multiple sclerosis (fMS) in persons with positive MS history, being the first such investigation performed in fMS cohort. METHODS: A case-control study based on the Belgrade population MS Registry was conducted. Cases for the sporadic MS (sMS) control group were randomly selected from the Registry, and matched with individuals with fMS at a ratio of 1:1. Spouses of the persons with fMS were included as a healthy control (HC) group. A specific questionnaire that was previously validated was used to obtain the data. To evaluate risk factors associated with breastfeeding for fMS occurrence compared with sMS and HC, multinomial regression analysis was performed to compute the relative risk ratios (RRR) along with 95% confidence intervals (95% CI). The analysis was afterwards repeated, stratified by sex. Both models were adjusted for potential confounding factors. RESULTS: A total of 393 participants were included in our case-control study, 131 per group. There were more individuals who were exclusively breastfed longer than six months in the sMS group compared to fMS group (RRR 2.01, 95% CI 1.22-3.32). After stratification by sex, exclusive breastfeeding was shown to be a protective factor for fMS only in male population, for individuals breastfed ≥4 months. The results of both the main and stratified analysis remained robust after adjustment. CONCLUSION: Our study findings indicate that breastfeeding reduces the risk of MS in infants with family history of the disease, although this protective effect may be limited to the male population. Further investigation into the differences in risk factors between fMS and sMS is warranted to gain a more comprehensive understanding of the disease.

Impact of the autonomic dysfunction on the quality of life in people with NMOSD and MS: An international cross-sectional study.

BACKGROUND: A substantial autonomic nervous system (ANS) dysfunction has been described in multiple sclerosis (MS) and recently, also in neuromyelitis optica spectrum disorder (NMOSD). The prevalence of ANS symptoms contributes to the chronic symptom burden in both diseases. The aim of our study was to assess ANS dysfunction in people with (pw) NMOSD and MS, using the Composite Autonomic Symptom Score-31 (COMPASS-31), and additionally, to evaluate if ANS dysfunction have impact on the quality of life of these patients. METHODS: We conducted cross-sectional study at three national referral neurological clinics in Serbia, Croatia, and Montenegro. A total of 180 consecutive subjects, 80 pwNMOSD and 100 pwMS, followed-up at these clinics, were enrolled in the study. Subjects included in the study completed: the validated versions of the COMPASS-31 and the Multiple Sclerosis Quality of Life-54 (MSQoL-54), and the Beck Depression Inventory (BDI). RESULTS: This study demonstrated that the total COMPASS-31 score > 0.0, implicating the presence of ANS dysfunction, was detected in almost all NMOSD and MS study participants tested (80/80, and 97/100, respectively). Our findings showed that autonomic symptom burden was statistically significantly correlated with decreased quality of life, in both NMOSD and MS cohorts. The independent predictors of the better quality of life in pwNMOSD were lower autonomic burden, particularly the absence of the orthostatic intolerance (p = 0.005), along with lower EDSS and BDI score (p ≤ 0.001). Similarly, in pwMS, independent predictors were EDSS, BDI, orthostatic intolerance, and the total COMPASS-31 (p ≤ 0.001). CONCLUSION: Our study demonstrated that a significant proportion of persons with both NMOSD and MS have considerable dysautonomic symptom burden which is correlated with the decreased quality of life. Further investigations are warranted in order to optimize treatment interventions in MS and NMOSD.

COVID-19 and vaccination against SARS-CoV-2 in patients with neuromyelitis optica spectrum disorders.

BACKGROUND: Reports on outcomes of COVID-19 in patients with neuromyelitis optica spectrum disorder (NMOSD) are scarce, as well as those related to the safety profile of the vaccines in this population. The aim of this survey is to present demographic and clinical characteristics of patients with NMOSD who developed COVID-19 and safety data of the COVID-19 vaccines in these persons. METHODS: This study comprise all patients from the Hospital registry of NMOSD, of the Clinic of Neurology in Belgrade, who fulfilled the 2015 NMOSD diagnostic criteria, and who after invitation by phone call, from April 10 to May 10, 2021, accepted to participate and provide information regarding COVID-19 and vaccination against Sars-CoV-2 (n = 53). RESULTS: Sixteen out of 53 enrolled NMOSD patients were diagnosed with COVID-19. In three cases (18.8%), severity of COVID-19 clinical manifestations warranted hospitalization, and one of these patients, died due to COVID-19 (case fatality ratio = 6.25%), after invasive mechanical ventilation. The remaining two patients had grade II COVID -19 severity and were hospitalized because of pneumonia, not requiring supplemental oxygen. Median EDSS in patients requiring hospitalization was 4.5, and in the non-hospitalized group, it was 3.0. Nine out of 53 patients received two doses of vaccine against Sars-Cov-2 (8 Sinopharm and one Pfizer). Pain at the site of application was the only vaccine-related adverse effect. CONCLUSIONS: Our survey indicates overall favourable COVID-19 outcome and encouraging safety profile of the vaccines in persons with NMOSD, in our cohort. Prospective studies are warranted to confirm these data.

Humoral response to SARS-CoV-2 infection and vaccines against COVID-19 in patients with neuromyelitis optica spectrum disorders: Impact of immunosuppressive treatment.

The aim of this study was to evaluate the humoral response to the SARS-CoV-2 infection and vaccination in the NMOSD patients, treated with various immunosuppresants (ISs). Serum IgG against the complete sequence of the receptor binding domain of the spike protein was measured using ELISA SARS-CoV-2 IgG, INEP, Belgrade. Seroconversion occurred in 8/10 patients with COVID-19, and in 5/9 after vaccination. One out of four patients treated with inebilizumab seroconverted (after COVID-19); antibodies were not detected in any of the remaining 3 patients who were vaccinated. Antibodies developed after COVID-19 in 4/5 patients treated with azathioprine and all treated with mycophenolate-mofetil, and after vaccination, in 5/6 patients treated with these ISs. Post-vaccination humoral response was impaired in our NMOSD patients treated with B-cell depleting therapies; seroconversion occurred in almost all patients treated with conventional synthetic disease modifying ISs.

Transverse myelitis following COVID-19: Insights from a multi-center study and systematic literature review.

INTRODUCTION: We aimed to provide insights into transverse myelitis (TM) following COVID-19 by analyzing cases treated at tertiary care neurology centers and a systemic review of the literature. METHODS: The retrospective observational multi-center study was conducted at the four university neurology departments in Croatia, Slovenia, Serbia, and Austria. We searched for acute myelitis cases that occurred during or after COVID-19. A systemic review of the literature on COVID-19 and transverse myelitis was performed. RESULTS: We identified 76 persons with TM associated with COVID-19, 13 from the multi-center study and 63 from the literature review. Most of the participants (55.6%) had an intermediate latency, 25.4% had short and 19% long latency from COVID-19 symptoms to TM. The clinical presentation consisted of the typical TM signs. More than half of the participants had inflammatory changes in the CSF, with rare patients having intrathecal OCB synthesis and positive serology for anti-MOG or anti-AQP4 antibodies. Persons with autonomic symptoms and CSF pleocytosis were significantly more common to have an intermediate latency of 8 to 21 days from COVID-19 to TM (p = 0.005 and p = 0.003; respectively). According to logistic regression analysis, only participants with lesions evident on spinal cord MRI compared to normal spinal cord MRI had reduced risks for poor recovery. >80% of participants were treated with a combination of corticosteroids and intravenous immunoglobulins or plasma exchange with 73% having incomplete recovery. CONCLUSION: Our study further characterizes clinical, laboratory, and MRI features, as well as treatment of TM associated with COVID-19.

Humoral response to SARS-CoV-2 COVID-19 vaccines in patients with multiple sclerosis treated with immune reconstitution therapies.

BACKGROUND: It has been generally accepted that people with MS (PwMS) should be vaccinated against COVID-19. The aim of our investigation was to evaluate the humoral response to natural SARS-CoV-2 infection and to two COVID-19 vaccines (BNT162b2 Pfizer-BioNTech and Beijing/Sinopharm BBIBP-CorV) in our cohort of PwMS under high efficacy disease modifying therapies (DMTs), cladribine and alemtuzumab. METHODS: Twenty two PwMS treated at the Clinic of Neurology, in Belgrade, who developed COVID-19 and/or were vaccinated against SARS-CoV-2, during treatment with cladribine and alemtuzumab, were included. Out of 18 patients treated with cladribine, 11 developed COVID-19, and 11 were vaccinated against SARS-CoV-2 (four with mRNA vaccine, 7 with Sinopharm). Four MS patients under alemtuzumab were vaccinated against SARS-CoV-2; three with mRNA, and one with Sinopharm vaccine. SARS-Cov-2 IgG response was measured using ELISA anti-spike protein-based serology (INEP, Belgrade, Serbia). RESULTS: All 7 patients under cladribine treatment who suffered from COVID-19, developed IgG antibodies, 2.0-5.5 months after last symptoms. All four (100%) patients under cladribine who were vaccinated with Pfizer-BioNTech vaccine, and three out of seven (42.9%) vaccinated with Sinopharm, developed antibodies. All 4 patients under alemtuzumab developed antibodies after vaccination. In all cases, seroprotection occurred, irrespective of timing of vaccination and absolute lymphocyte count. CONCLUSION: Our findings in a small number of highly active PwMS in whom, lymphodepleting, immune reconstitution therapies, were applied in order to successfully manage MS, indicate that in a number of these patients it was possible to develop at the same time seroprotection in these patients after COVID-19 vaccination in these complex circumstances.

Variations of gamma-ray background in the Belgrade shallow underground low-level laboratory.

During the last three years we investigated the variations of background simultaneously in two laboratories, the ground level (GLL) and the underground laboratory. The Forbush-like effect from March 2010 was observed in the GLL using a Ge detector and plastic veto scintillator. The underground plastic scintillator saw the same effect but the coincident veto spectrum did not detect the decrease of cosmic-ray intensity. Using a time series analysis of prominent post-radon lines, a significant radon daily variability was detected in the Ge detector background spectrum, but only in the GLL.

Correlative and multivariate analysis of increased radon concentration in underground laboratory.

The results of analysis using correlative and multivariate methods, as developed for data analysis in high-energy physics and implemented in the Toolkit for Multivariate Analysis software package, of the relations of the variation of increased radon concentration with climate variables in shallow underground laboratory is presented. Multivariate regression analysis identified a number of multivariate methods which can give a good evaluation of increased radon concentrations based on climate variables. The use of the multivariate regression methods will enable the investigation of the relations of specific climate variable with increased radon concentrations by analysis of regression methods resulting in 'mapped' underlying functional behaviour of radon concentrations depending on a wide spectrum of climate variables.