Publications by authors named "Ivan Zak"

4 Publications

  • Page 1 of 1

Cognitive changes after methanol exposure: Longitudinal perspective.

Toxicol Lett 2021 Oct 17;349:101-108. Epub 2021 Jun 17.

Department of Neurology and Centre of Clinical Neuroscience, First Faculty of Medicine, Charles University and General University Hospital, Prague, Czech Republic. Electronic address:

Background: From 2012 to 2013, there was a mass methanol poisoning outbreak in the Czech Republic. Methanol metabolites can cause specific lesions in the basal ganglia, subcortical white matter, and optic nerve. However, long-term sequelae of methanol poisoning on cognitive functioning have not yet been explored. The current study aimed to delineate the cognitive changes observed in methanol poisoning survivors in the seven years since 2012.

Methods: We conducted longitudinal research with repeated measurements in 2013, 2015, 2017 and 2019 to evaluate the development of cognitive changes after acute methanol poisoning. A complex neuropsychological battery consisted of tests of global cognitive performance, auditory and visual attention, executive functioning, learning and memory, working memory and language. Motor performance measures and depression scale were also included.

Results: Repeated measures ANOVA of four measurements with post-hoc tests showed a significant decline in the Mini-Mental State Examination (p = 0.007); however, other parameters were not significantly decreasing. In comparison to normative values, the z-scores for each test measure, in the memory domain, in particular, ranged from 43 to 60 % of participants below 1.5 SD. Mild to severe depression levels from the onset of poisoning improved during the seven years, returning to normal in up to 27 % of participants.

Conclusion: In the longitudinal perspective, methanol poisoning survivors manifest progressive global cognitive decline and overall persistent below-average cognitive performance with some improvements in the frequency of depressive symptoms.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.toxlet.2021.06.008DOI Listing
October 2021

Efficiency of I-ioflupane SPECT as the marker of basal ganglia damage in acute methanol poisoning: 6-year prospective study.

Clin Toxicol (Phila) 2021 Mar 7;59(3):235-245. Epub 2020 Aug 7.

Department of Occupational Medicine, First Faculty of Medicine, Charles University, Prague, Czech Republic.

Context: Investigate whether I-ioflupane SPECT (DaT SPECT) has the potential as a marker of basal ganglia damage in acute methanol poisoning.

Methods: Prospective, single-centre, cohort study of patients with confirmed methanol poisoning was conducted. DaT SPECT was performed twice with semi-quantification using DaTQUANT and MRI-based volumetry was calculated. Specific binding ratios (SBR) of striatum, caudate nucleus, and putamen were correlated with laboratory parameters of outcome, volumetric data, and retinal nerve fibres layer (RNFL) thickness measurements.

Results: Forty-two patients (mean age 46.3 ± 4.2 years; 8 females), including 15 with MRI-detected putamen lesions (group I) and 27 patients with intact putamen (group II), underwent DaT SPECT. Volumetry was calculated in 35 of the patients assessed. SBR values for the left putamen correlated with putamen volume ( = 0.665;  < 0.001). Decreased bilateral SBR values were determined for the striatum and the putamen, but not for the nucleus caudate, in group I ( < 0.05). Significant correlation was observed between the SBR of the posterior putamen and arterial blood pH ( = 0.574;  < 0.001) and other toxicological parameters of severity of poisoning/outcome including serum lactate, glucose, and creatinine concentrations ( < 0.05). The SBR of the posterior putamen positively correlated with the global RNFL thickness ( < 0.05). ROC analysis demonstrated a significant discriminatory ability of SBR of the posterior putamen with AUC = 0.753 (95%CI 0.604-0.902;  = 0.007). The multivariate regression model demonstrated that arterial blood pH, age, and gender were the most significant factors associated with SBR of the posterior putamen.

Conclusion: DaT SPECT demonstrates significant potential for the diagnosis of methanol-induced basal ganglia damage.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1080/15563650.2020.1802033DOI Listing
March 2021

Peripheral polyneuropathy after acute methanol poisoning: Six-year prospective cohort study.

Neurotoxicology 2020 07 5;79:67-74. Epub 2020 May 5.

Toxicological Information Centre, General University Hospital, Prague, Czech Republic; Department of Occupational Medicine, 1st Faculty of Medicine, Charles University, Prague, Czech Republic.

Background: Methanol is a widely used industrial short-chain aliphatic alcohol with known neurotoxic properties. Mass poisoning outbreaks due to the consumption of methanol-adulterated alcoholic drinks present a challenge to healthcare providers due to the high mortality and serious central nervous system (CNS) damage in survivors. However, the impact of methanol exposure on the peripheral nervous system is unknown.

Objectives: To investigate the role of acute methanol exposure in the development of peripheral polyneuropathy (PNP) during the years following discharge from the hospital.

Methods: A total of 55 patients with confirmed methanol poisoning (mean age of 47.9 ± 3.6 years; 9 females) were examined 4 times within a 6-year prospective longitudinal cohort study. The program included neurological and electromyographic examinations, visual evoked potentials, ocular examinations with retinal nerve fibre layer thickness measurements, brain magnetic resonance imaging, and a series of biochemical and toxicological tests.

Results: PNP was observed in 20/55 (36 %) patients, which, in most of the cases, was mild axonal sensorimotor neuropathy. In 8/55 (15 %) patients, worsening of electromyographic findings was registered during the follow-up period, including 5 cases with newly diagnosed PNP and 3 cases of PNP progression. In one subject, complete reversal of PNP was registered after cessation of alcohol intake. The patients with PNP were significantly older (57.3 ± 5.3 versus 42.5 ± 3.9 years; p < 0.001), with higher blood glucose (5.93 ± 0.97 versus 4.81 ± 0.32 mmol/L; p = 0.035) and lower vitamin B (45.5 ± 7.4 versus 57.5 ± 5.2 ug/L; p = 0.015) concentrations. The number of chronic alcohol abusers was significantly higher in the PNP group (17/20 versus 20/35; p = 0.034). No associations between PNP prevalence/ dynamics and acute parameters of poisoning severity, arterial blood pH (7.26 ± 0.07 with PNP versus 7.18 ± 0.09 without PNP; p = 0.150), or serum methanol (1320.0 ± 700.0 with PNP versus 1430.0 ± 510.0 mg/L without PNP; p = 0.813) and ethanol (460.0 ± 560.0 with PNP versus 340.0 ± 230.0 mg/L without PNP; p = 0.675) concentrations at admission were found. No difference in the number of patients with visual (9/20 with PNP versus 12/35 patients without PNP; p = 0.431) and CNS sequelae (9/20 with PNP versus 15/35 patients without PNP; p = 0.877) of poisoning was present.

Discussion: Despite the relatively high number of PNP cases, no association was found between the severity of acute methanol poisoning and the prevalence of PNP and its dynamics during six years of observation. We did not find an association between methanol-induced visual/ brain damage and the prevalence of PNP in survivors of poisoning. A high prevalence of PNP and its progression might be attributed to other causes, mainly a history of chronic alcohol abuse and insufficiently treated diabetes mellitus. Our results highlight the importance of complete cessation of alcohol consumption and better control of glycaemia in diabetic patients in the prevention and treatment of peripheral PNP.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.neuro.2020.04.010DOI Listing
July 2020

Acute exposures to e-cigarettes and heat-not-burn products reported to the Czech Toxicological Information Centre over a 7-year period (2012-2018).

Basic Clin Pharmacol Toxicol 2020 Jul 19;127(1):39-46. Epub 2020 Mar 19.

Toxicological Information Centre, General University Hospital, Prague, Czech Republic.

E-cigarettes and heat-not-burn cigarettes (HNBC) present new health risks due to their rising popularity, high content of nicotine and serious adverse effects. The objective of the study was to analyse the cases of acute exposure to e-cigarettes, e-liquids and HNBC products containing nicotine that led to toxicological consultations at our poisons control centre during a 7-year period (2012-2018) and identify the categories of special concern that require further investigation and intervention. The demographic, toxicological and clinical data were analysed by descriptive statistics. Poisoning severity score (PSS) was estimated. From 119 229 consultations, 148 cases concerned acute exposure to e-cigarettes. Children and adolescents were exposed in 91 (61%) cases, including exposure of neonates and infants in 54 (36%) cases. The main route of exposure was ingestion in 129 (87%), inhalation in nine (6%), ocular in six (4%) and intravenous administration in three (2%) cases. The source of exposure was the cartridge with e-liquid (107; 72%), refillable tank in 29 (20%) and HNBC refill in nine (6%) cases. The reason for exposure was accidental in 110 (74%), incorrect application of the device in 10 (7%), abuse in six (4%), suicide attempt in six (4%) and other/unknown in 16 (11%) cases. The dose estimation was severe/lethal in 6 (4%), toxic in 53 (36%), low-to-moderate in 35 (24%) and unknown in 54 (36%) cases. Vomiting was observed in 38 (26%) patients; 72% of patients were hospitalised. In symptomatic cases, 41 patient had PSS 1, 12 patients had PSS 2, and one patient had PSS 3. Activated charcoal was applied in 57 (39%) patients, and symptomatic treatment was recommended in 75 (51%) patients. Cases of unintentional exposure of children demonstrate the need for preventive risk reduction measures.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1111/bcpt.13393DOI Listing
July 2020
-->