A thorough analysis of the occurrence, removal and environmental risks of organic micropollutants in a full-scale hybrid membrane bioreactor fed by hospital wastewater

The Urban Wastewater Treatment Directive recent draft issued last October 2022 pays attention to contaminants of emerging concern including organic micropollutants (OMPs) and requires the removal of some of them at large urban wastewater treatment plants (WWTPs) calling for their upgrading. Many investigations to date have reported the occurrence of a vast group of OMPs in the influent and many technologies have been tested for their removal at a lab- or pilot-scale. Moreover, it is well-known that hospital wastewater (HWW) contains specific OMPs at high concentration and therefore its management and treatment deserves attention. In this study, a 1-year investigation was carried out at a full-scale membrane bioreactor (MBR) treating mainly HWW. To promote the removal of OMPs, powdered activated carbon (PAC) was added to the bioreactor at 0.1 g/L and 0.2 g/L which resulted in the MBR operating as a hybrid MBR. Its performance was tested for 232 target and 90 non-target OMPs, analyzed by UHPLC-QTOF-MS using a direct injection method. A new methodology was defined to select the key compounds in order to evaluate the performance of the treatments. It was based on their frequency, occurrence, persistence to removal, bioaccumulation and toxicity. Finally, an environmental risk assessment of the OMP residues was conducted by means of the risk quotient approach. The results indicate that PAC addition increased the removal of most of the key OMPs (e.g., sulfamethoxazole, diclofenac, lidocaine) and OMP classes (e.g., antibiotics, psychiatric drugs and stimulants) with the highest loads in the WWTP influent. The hybrid MBR also reduced the risk in the receiving water as the PAC dosage increased mainly for spiramycin, lorazepam, oleandomycin. Finally, uncertainties and issues related to the investigation being carried out at full-scale under real conditions are discussed.

Insight into the degradation of amino substituted benzimidazo[1,2-a]quinolines via a combined experimental and density functional theory study

Heterocyclic compounds have been shown to be potential chemotherapeutic agents, especially the benzimidazole derivatives studied in this work. The ultimate goal in the search for biologically active and effective molecules is to commercialize a product whose stability must be reliable. Therefore, in the development of drugs, forced degradation experiments are performed under the environmental conditions to which they are subjected during transportation and storage to ensure quality and safety before marketing. Hydrolytic, thermal, photolytic, and degradation in the presence of hydrogen peroxide are experimental stress tests to which the newly synthesized compounds were subjected to gain insight into the degradation pathways of the analytes. Degradation of two benzimidazole derivatives was observed under all applied conditions while the major impact showed photolysis with ten and four degradation products, respectively. In total, eighteen major degradation products were detected and identified using high-resolution mass spectrometry. Computer models in the TEST program were applied to the proposed structures to evaluate the bioaccumulation factor, toxicity, and mutagenicity of the analyzed compounds, while density functional theory analysis (DFT) revealed factors affecting the vulnerability of systems towards exceeding acidic/basic conditions and H2O2.

Simultaneous determination of macrolides in water samples by solid-phase extraction and capillary electrophoresis

Solid-phase extraction (SPE) coupled with capillary electrophoresis (CE) for the determination of macrolide antibiotics (azithromycin, clarithromycin, roxithromycin, tylosin) and tiamulin in water samples was described in this article. These compounds were extracted with different types of sorbents ( Oasis HLB, C18, C8, SDB, and Strata-X) and different masses of sorbents (60 mg, 200 mg, and 500 mg) using different organic solvents (methanol, ethanol, and acetonitrile) and different pH values of water samples (pH 7.00, 8.00, and 9.00). It was found that the highest extraction efficiency of the studied compounds was obtained with 200 mg/3 mL C18 cartridges with methanol as eluent at pH 9.00 of the water sample. The developed SPE-CE method for macrolide antibiotics and tiamulin was validated for linearity, precision, repeatability, the limit of detection (LOD), the limit of quantification (LOQ), and recovery. Good linearity was obtained in the range of 0.3-30 mg L-1 depending on the drug, with correlation coefficients higher than 0.9958 in all cases except clarithromycin (0.9873). Expanded measurement uncertainties were calculated for each pharmaceutical, accounting for 20.31 % (azithromycin), 38.33 % (tiamulin), 28.95 % (clarithromycin), 26.99 % (roxithromycin), and 21.09 % (tiamulin). Uncertainties associated with precision and calibration curves contributed the most to the combined measurement uncertainty. The method was successfully applied to the analysis of production waste-water from the pharmaceutical industry.

Optimisation of Solid-Phase Extraction and LC-MS/MS Analysis of Six Breast Cancer Drugs in Patient Plasma Samples

In the development of bioanalytical LC-MS methods for the determination of drugs in plasma samples in a clinical setting, adequate sample preparation is of utmost importance. The main goals are to achieve the selective extraction of the analytes of interest and attain thorough matrix removal while retaining acceptable ecological properties, cost-effectiveness, and high throughput. Solid-phase extraction (SPE) offers a versatile range of options, from the selection of an appropriate sorbent to the optimisation of the washing and elution conditions. In this work, the first SPE method for the simultaneous extraction of six anticancer drugs used in novel therapeutic combinations for advanced breast cancer treatment-palbociclib, ribociclib, abemaciclib, anastrozole, letrozole, and fulvestrant-was developed. The following sorbent chemistries were tested: octylsilyl (C8), octadecylsilyl (C18), hydrophilic-lipophilic balance (HLB), mixed-mode cation-exchange (MCX and X-C), and mixed-mode weak cation-exchange (WCX), with different corresponding elution solvents. The samples were analysed using LC-MS/MS, with a phenyl column (150 × 4.6 mm, 2.5 μm). The best extraction recoveries (≥92.3%) of all analytes were obtained with the C8 phase, using methanol as the elution solvent. The optimised method was validated in the clinically relevant ranges, showing adequate precision (inter-day RSD ≤ 14.3%) and accuracy (inter-day bias -12.7-13.5%). Finally, its applicability was successfully proven by the analysis of samples from breast cancer patients.

Influence of Organic Matter on the Sorption of Cefdinir, Memantine and Praziquantel on Different Soil and Sediment Samples

Pharmaceuticals are known for their great effects and applications in the treatment and suppression of various diseases in human and veterinary medicine. The development and modernization of science and technologies have led to a constant increase in the production and consumption of various classes of pharmaceuticals, so they pose a threat to the environment, which can be subjected to the sorption process on the solid phase. The efficiency of sorption is determined by various parameters, of which the physicochemical properties of the compound and the sorbent are very important. One of these parameters that determine pharmaceutical mobility in soil or sediment is the soil−water partition coefficient normalized to organic carbon (Koc), whose determination was the purpose of this study. The influence of organic matter, suspended in an aqueous solution of pharmaceutical (more precisely: cefdinir, memantine, and praziquantel), was studied for five different types of soil and sediment samples from Croatia. The linear, Freundlich, and Dubinin−Raduskevich sorption isotherms were used to determine specific constants such as the partition coefficient Kd, which directly describes the strength of sorbate and sorbent binding. The linear model proved to be the best with the highest correlation coefficients, R2 > 0.99. For all three pharmaceuticals, a positive correlation between sorption affinity described by Kd and Koc and the amount of organic matter was demonstrated.

Photocatalytic Activity of TiO2 for the Degradation of Anticancer Drugs

To prevent water pollution, photocatalysis is often used to remove small molecules such as drugs by generating reactive species. This study aimed to determine the photocatalytic activity of two anticancer drugs, imatinib and crizotinib, and to investigate various influences that may alter the kinetic degradation rate and ultimately the efficacy of the process. In order to obtain optimal parameters for the removal of drugs with immobilized TiO₂, the mutual influence of the initial concentration of the contaminant at environmentally relevant pH values was investigated using the response surface modeling approach. The faster kinetic rate of photocatalysis was obtained at pH 5 and at the smallest applied concentration of both drugs. The photocatalytic efficiency was mostly decreased by adding various inorganic salts and organic compounds to the drug mixture. Regarding the degradation mechanism of imatinib and crizotinib, hydroxyl radicals and singlet oxygen showed a major role in photochemical reactions. The formation of seven degradation products for imatinib and fifteen for crizotinib during the optimal photocatalytic process was monitored by high-resolution mass spectrometry (HPLC-QqTOF). Since the newly formed products may pose a hazard to the environment, their toxicity was studied using Vibrio fischeri, where the significant luminescence inhibition was assessed for the mixture of crizotinib degradants during the photocatalysis from 90 to 120 min.

Removal of micropollutants using a membrane bioreactor coupled with powdered activated carbon - A statistical analysis approach

The occurrence of micropollutants in wastewater is largely documented as well as the environmental risk posed by their residues in the aquatic environment. Many investigations have been carried out and plan to study and improve their removal efficiency in existing wastewater treatment plants. At the same time, efforts are being made to develop new technologies or upgrade existing ones to increase the removal of a selection of micropollutants. Due to the great variability in their chemical and physical properties, it would be advisable to find representative compounds or identify the factors which most influence the removal mechanisms under specific conditions. This study analyses the removal efficiencies of a great number of micropollutants in wastewater treated in a membrane bioreactor coupled with powdered activated carbon (PAC), which was the subject of a review article we have recently published. The main operational parameters (i.e. PAC dosage, PAC retention time and sludge retention time) and compound physico-chemical properties (i.e. octanol-water distribution coefficient, charge and molecular weight) were first selected on the basis of a dedicated screening step and then an attempt was carried out to clarify their influence on the removal of micropollutants from wastewater during its treatment. To this end, a statistical analysis, mainly based on exploratory methods (cluster analysis and principal component analysis) and regression analysis, was carried out to compare and discuss the different results published in the scientific literature included in the cited review article. It emerged, that, based on the collected dataset, micropollutant charge and LogD_ow seem to play the most important role in the removal mechanisms occurring in MBR coupled with PAC.

Sorption of cefdinir, memantine, praziquantel and trimethoprim in sediment and soil samples

The everyday use of various pharmaceuticals to treat humans or animals means that they are increasingly found in the environment. Contamination of the soil can cause the active ingredients to be strongly sorbed to the soil or sediment. In the worst case, they can also be expected to occur in the aquatic environment due to their different polarity. In this study, four drugs from different therapeutic classes (trimetoprim, memantine, cefdinir, praziquantel) were used in dissolved form in two sediment and three soil samples to obtain data that can describe their fate and behavior in the environment. The sorption affinities of the pharmaceuticals were described using linear, Freundlich and Dubinin-Radushkevich sorption isotherms. The highest K_d values were obtained for cefdinir, while memantine and praziquantel tended to be present in water due to their very low sorption coefficients. The studied influence of pH showed a negative trend for memantine and trimetoprim, while an increase in ionic strength resulted in higher K_d values for all drugs. The sorption mechanism for all tested samples was best described by the pseudo-secondary kinetic model (R² > 0.9999).

Activated carbon coupled with advanced biological wastewater treatment: A review of the enhancement in micropollutant removal

This study consists of a review on the removal efficiencies of a wide spectrum of micropollutants (MPs) in biological treatment (mainly membrane bioreactor) coupled with activated carbon (AC) (AC added in the bioreactor or followed by an AC unit, acting as a post treatment). It focuses on how the presence of AC may promote the removal of MPs and the effects of dissolved organic matter (DOM) in wastewater. Removal data collected of MPs are analysed versus AC dose if powdered AC is added in the bioreactor, and as a function of the empty bed contact time in the case of a granular activated carbon (GAC) column acting as a post treatment. Moreover, the enhancement in macropollutant (organic matter, nitrogen and phosphorus compounds) removal is analysed as well as the AC mitigation effect towards membrane fouling and, finally, how sludge properties may change in the presence of AC. To sum up, it was found that AC improves the removal of most MPs, favouring their sorption on the AC surface, promoted by the presence of different functional groups and then enhancing their degradation processes. DOM is a strong competitor in sorption on the AC surface, but it may promote the transformation of GAC in a biologically activated carbon thus enhancing all the degradation processes. Finally, AC in the bioreactor increases sludge floc strength and improves its settling characteristics and sorption potential.

Miniaturized analytical methods for determination of environmental contaminants of emerging concern - A review

The determination of contaminants of emerging concern (CECs) in environmental samples has become a challenging and critical issue. The present work focuses on miniaturized analytical strategies reported in the literature for the determination of CECs. The first part of the review provides brief overview of CECs whose monitoring in environmental samples is of particular significance, namely personal care products, pharmaceuticals, endocrine disruptors, UV-filters, newly registered pesticides, illicit drugs, disinfection by-products, surfactants, high technology rare earth elements, and engineered nanomaterials. Besides, an overview of downsized sample preparation approaches reported in the literature for the determination of CECs in environmental samples is provided. Particularly, analytical methodologies involving microextraction approaches used for the enrichment of CECs are discussed. Both solid phase- and liquid phase-based microextraction techniques are highlighted devoting special attention to recently reported approaches. Special emphasis is placed on newly developed materials used for extraction purposes in microextraction techniques. In addition, recent contributions involving miniaturized analytical flow techniques for the determination of CECs are discussed. Besides, the strengths, weaknesses, opportunities and threats of point of need and portable devices have been identified and critically compared with chromatographic methods coupled to mass chromatography. Finally, challenging aspects regarding miniaturized analytical methods for determination of CECs are critically discussed.

Nitrofurantoin in sediments and soils: Sorption, isotherms and kinetics

Nitrofurantoin is nitrofuran antibacterial drug that is most used as a veterinary pharmaceutic compound. This compound, as well as other pharmaceuticals can greatly affect the environment, the soil and organisms in it and pollute aquatic ecosystems. Since it has been used for only a few decades, knowledge of their fate and behaviour in the environment is still limited. Because of that, the aim of this study was to experimentally determine the K_d values of nitrofurantoin in seven different natural soil and seven different sediment samples with different physico-chemical properties. Sorption phenomena were described with Linear, Freundlich and Dubinin-Radushkevich sorption isotherms. Obtained sorption coefficients (K_d) ranged from 3.967 to 5.121 mLg^-1 for sediment samples and 3.634-43.06 mL g^-1 for soil samples. The influence of ionic strength and pH of the nitrofurantoin solution and kinetics of the sorption and desorption process were also investigated. Results show that an increase in ionic strength and pH reduces the values of sorption coefficient while the mechanism of nitrofurantoin sorption is the best described with the kinetic model of pseudo-second order.

GC-MS Modified Quechers Method for Multiresidue Pesticide Determination in Red Wine

This work reports a new selective and accurate multiresidue procedure for determination of 25 pesticides in red wine by GC-MS. Proposed procedure uses an original approach in sample preparation technique based on QuEChERS theory. Main focus of method development was modification of salts thus increasing ionic strength of solution which improved pesticides partitioning and extraction efficiency. LOQs were in the range 0.01–250 μg L–1 with 56 % of target pesticides below or equal to 10 μg L–1. RSD for most pesticides was < 20 % and recoveries were in the range 70–120 %. Matrix effect was found to be high for five pesticides confirming sample preparation procedure to be efficient. The proposed procedure was applied to 12 wine samples of different variety with determination of 40 % of target pesticides. Developed GC-MS methodology provides novel, selective and accurate approach for determination of 25 pesticide residues in red wine.

Fate of febantel in the aquatic environment-the role of abiotic elimination processes

Febantel is widely used anthelmintic drug active against a range of gastrointestinal parasites in animals. Despite the fact that it has been detected in the aquatic environment, there is no information on its environmental fate. Therefore, abiotic elimination processes of febantel in the aquatic environment have been studied. The results of direct and indirect photodegradation experiments showed that febantel was persistent against solar radiation. Kinetics of hydrolytic elimination was pH and temperature dependent with half-lives in the range from 210 min to 99 days. Febantel metabolites, fenbendazole and fenbendazole sulfone, were found as major degradation products using high-resolution mass spectrometry. The proposed hydrolytic degradation pathway consisted of the base catalyzed hydrolysis followed by consecutive oxidative cyclization to the five-membered ring of the benzo-imidazole derivative. Aquatic toxicity of febantel and its hydrolytic mixture were evaluated toward the luminescence bacteria Vibrio fischeri. Investigation of febantel sorption onto river sediments showed that the best agreement was obtained with the linear model (R² > 0.99), while the rate of sorption is the best described with the kinetic model of pseudo-second order. The organic carbon-normalized sorption coefficient, K_OC, ranged from 1490 to 3894 L kg^-1 for five sediment samples. The results of this research demonstrate that febantel persist in the natural waters and potentially could travel far from the source.

Sorption of albendazole in sediments and soils: Isotherms and kinetics

Albendazole is a broad-spectrum anthelmintic drug effective against gastrointestinal parasites in humans and animals. Despite the fact that it has been detected in environment (water, sediment and soil), there is no information on its fate in the environment. So, in order to understand the sorption process of albendazole in environment, the sorption mechanism and kinetic properties were investigated through sorption equilibrium and sorption rate experiments. For that purpose, batch sorption of albendazole on five sediment samples and five soil samples from Croatia's region with different physico-chemical properties was investigated. Except physico-chemical properties of used environmental solid samples, the effects of various parameters such as contact time, initial concentration, ionic strength and pH on the albendazole sorption were studied. The K_d parameter from linear sorption model was determined by linear regression analysis, while the Freundlich and Langmuir sorption models were applied to describe the equilibrium isotherms. The estimated K_d values varied from 29.438 to 104.43 mLg^-1 at 0.01 M CaCl₂ and for natural pH value of albendazole solution (pH 6.6). Experimental data showed that the best agreement was obtained with the linear model (R² > 0.99), while the rate of albendazole sorption is the best described with the kinetic model of pseudo-second-order. Obtained results point to a medium or even strong sorption of albendazole for soil or sediment particles, which is particularly dependent on the proportion of organic matter, pH, copper and zinc in them.

Isotherm, kinetic, and thermodynamic study of ciprofloxacin sorption on sediments

In this study, equilibrium isotherms, kinetics and thermodynamics of ciprofloxacin on seven sediments in a batch sorption process were examined. The effects of contact time, initial ciprofloxacin concentration, temperature and ionic strength on the sorption process were studied. The K _d parameter from linear sorption model was determined by linear regression analysis, while the Freundlich and Dubinin-Radushkevich (D-R) sorption models were applied to describe the equilibrium isotherms by linear and nonlinear methods. The estimated K _d values varied from 171 to 37,347 mL/g. The obtained values of E (free energy estimated from D-R isotherm model) were between 3.51 and 8.64 kJ/mol, which indicated a physical nature of ciprofloxacin sorption on studied sediments. According to obtained n values as measure of intensity of sorption estimate from Freundlich isotherm model (from 0.69 to 1.442), ciprofloxacin sorption on sediments can be categorized from poor to moderately difficult sorption characteristics. Kinetics data were best fitted by the pseudo-second-order model (R ² > 0.999). Thermodynamic parameters including the Gibbs free energy (ΔG°), enthalpy (ΔH°) and entropy (ΔS°) were calculated to estimate the nature of ciprofloxacin sorption. Results suggested that sorption on sediments was a spontaneous exothermic process.

The sorption of sulfamethazine on soil samples: isotherms and error analysis

In this paper, batch sorption of sulfamethazine on eight soil samples (six from Croatia and two from Bosnia and Hercegovina) with different organic matter contents ranging from 1.52 to 12.8% was investigated. The effects of various parameters such as agitation time, initial concentration, and ionic strength on the sulfamethazine sorption were studied. The experimental data were analysed using a one-parameter model, Linear isotherm, and two two-parameter models, the Freundlich and Dubinin-Radushkevich isotherms. The goodness of fit was measured using the linear regression and the determination coefficient (R(2)) value. Also, the equilibrium data of the two-parameter models were analysed using the residual root mean square error (RMSE), the sum of squares of errors (ERRSQ), and a composite fractional error function (HYBRID). Non-linear regression has better characteristics for analysing experimental data. The obtained sorption coefficients Kd (from 0.25 to 8.10 mL/g) and the Freundlich sorption coefficients KF (from 1.16 to 7.99 (μg/g)(mL/μg)(1/n)) exhibited quite low values, which indicated that sulfamethazine is weakly adsorbed on the evaluated soils, is highly mobile, and has a great potential to penetrate and pollute the ground water. The Dubinin-Radushkevich isotherm was used to estimate the apparent free energy of sorption.

Optimization of matrix solid-phase dispersion for liquid chromatography tandem mass spectrometry analysis of 12 pharmaceuticals in sediments

The matrix solid-phase dispersion (MSPD) technique accompanied with LC-MS/MS detection for the purpose of determination of 12 pharmaceuticals (sulfaguanidine, sulfadiazine, sulfamethazine, sulfamethoxazole, trimethoprim, roxithromycin, praziquantel, febantel, enrofloxacin, ciprofloxacin, norfloxacin and procaine) applied to sediment samples has been described in this paper. Different parameters, such as the type of solid phase, the elution solvent and its volume have been investigated. The analytes were successfully extracted by C18 as an MSPD sorbent with 5 mL of acetonitrile:5% of oxalic acid=6:4 (v/v) as an elution solvent. The proposed method provides a linear response over the concentration range of 0.0005-100 μg/g, depending on pharmaceuticals with correlation coefficients above 0.9928 in all cases except for trimethoprim (0.9889). Also, the method has revealed low limits of detection (0.125-500 ng/g), good precision (intra and inter-day), a relative standard deviation below 15% and recoveries above 80%, except for roxithromycin, febantel and enrofloxacin. The method has been successfully applied to analysis of different sediment samples.

RO/NF membrane treatment of veterinary pharmaceutical wastewater: comparison of results obtained on a laboratory and a pilot scale

BACKGROUND

Emerging contaminants (ECs) are commonly derived from industrial wastewater, which is often a consequence of an inadequate treatment of the latter. Improperly pretreated pharmaceutical wastewater could cause difficulties in operations of wastewater treatment plants while incomplete elimination of ECs during the processing might result in their appearance in drinking water.

METHODS

This paper deals with membrane treatment of pharmaceutical wastewater on a laboratory and a pilot scale as well as with the removal of the following veterinary pharmaceuticals (VPs) (sulfamethoxazole, trimethoprim, ciprofloxacin, dexamethasone, and febantel).

RESULTS

The pretreatment of pharmaceutical wastewater by means of coagulation and microfiltration (MF) prevented the irreversible fouling of the fine porous structure of the reverse osmosis (RO) and nanofiltration (NF) membranes which were used in the final stage of wastewater processing. The percentage of the removal of the selected VPs ranges from 94% to almost 100% in the case of NF and RO membranes in both scales. The recovery percentage concerning the pilot scale amounted to 88%. Membrane cleaning was successfully carried out in both scales.

CONCLUSIONS

The differences in retention between laboratory and pilot tests are due to different raw wastewater quality and different recovery and hydrodynamic of the two systems. Fouling and concentration polarization were more pronounced in laboratory setup (frame-plate module) than in pilot unit (spiral module). The proposed integrated membrane treatment (coagulation, MF, NF, and RO) can be employed for treatment of wastewater originating from pharmaceutical factory. The obtained permeate can be safely discharged to sewer system or could be reused in manufacturing process.

[Clinical characteristics and therapy of neurosyphilis in patients who are negative for human immunodeficiency virus]

INTRODUCTION

Neurosyphilis is still a significant medical problem in developing countries and its occurrence in HIV infection is the reason for a growing number of new cases in developed countries [1-4]. Personality changes are the commonest symptom of late neurosyphilis [5]. Neurologic deficits are usually due to syphilitic vasculitis with lacunar infarctions [6]. The laboratory confirmation of neurosyphilis must depend on a cluster of tests (Venereal Disease Research Laboratories--VDRL; Fluorescent Treponemal Antibody-Absorption--FTA-ABS; Treponema Pallidum Immobilization--TPI or Nelson-Mayer). The diagnosis of active neurosyphilis also requires an inflammatory cerebrospinal fluid (CSF) test [4].

METHODS

A retrospective study of hospitalized neurosyphilitic patients at the Institute of Neurology, Belgrade, Serbia, was carried out. Between 1990 and 1996 seven cases were found: five males and two females, aged from 22 to 66 years, mean 56 years. All were in tertiary stage and HIV negative. None of them reported previous veneral disease and only one reported meningitis. In all patients neurological examination, VDRL and TPI in blood and CSF, CT or MRI of the brain, Mini Mental State (MMS) test [11] and psychiatric evaluation were performed. To patients with active disease 24 million units of crystalline penicillin were administered, in divided daily doses in continuous intravenous infusions for three weeks.

RESULTS

Symptoms. Five patients (71%) had gait disturbances, four (57%) headache, three (43%) hearing loss, speech complaints, forgetfulness, mood changes, and two (29%) seizures and stroke-like episodes. Malaise, diplopia, visual loss, vertigo, loss of sphincter control and paresthesia were noticed in one patient (14%). Neurologic findings. Five patients (71%) had pupillary changes. In four (57%) of them we found hemiparesis, gait disturbances and signs of cerebellar involvement, in three (43%) hearing loss, dysarthria, paraparesis, hypesthesia for light touch, mood disorders (depression in two, hypomania in one), mild cognitive decline and tremor of the tongue and hands. Lesion of the second and the sixth cranial nerve, position sense and positive release signs were recorded in one patient (14%). Gonarthrotic changes were observed in two (29%) patients. Cerebrospinal fluid. Elevated cell count and high protein level were detected in four (57%) patients. Three had also positive oligoclonal bands. Serological tests. In six patients (86%) serological tests for syphilis were positive (VDRL and/or Nelson-Mayer Test) in serum and in three (43%) in CSF. Results in one patient were negative both regarding serum and CSF, as he was treated for secondary syphilis in his twenties (now 65 years old) presumably as a "burnt out" case with neurologic sequelae. Neuroimaging. CT and MRI of the brain showed cortical and subcortical reduction in the brain parenchyma in four (57%) and multiischaemic changes in two (29%) patients. Therapy. Crystalline penicillin was administered to five patients with no side effects. Improvement of mood and cognitive status were noted in three patients, improvement of neurologic status in two subjects and arrest of progression in two patients.

DISCUSSION

None of our patients reported previous venereal disease. They complained of impaired gait, headache, hearing loss, speech difficulties, forgetfulness, and mood changes. Pupillary changes, hemiparesis, gait disturbances and cerebellar signs, hearing loss, dysarthria, paraparesis, hypesthesia, mood disorders, mild cognitive decline and tremor of the tongue and hands were found during the examination. Pupillary signs are the most important symptoms because they can point to neurosyphilis. A two-step approach is recommended for establishing the diagnosis of syphilis with simple nontreponemal tests for screening purpose, and specific treponemal tests for its confirmation [21]. In our patients all but one were positive for syphilis in serum-tests and/or CSF. (ABS

[Diagnosis of Lyme neuroborreliosis]

Lyme neuroborreliosis is a disease of the central and/or peripheral nervous system caused by spirochete Borrelia burgdorferi. The diagnosis of Lyme neuroborreliosis is based on the clinical picture, differential diagnosis, serological tests with two-step approach and confirmation of positive results, monitoring of antibody titers and effects of adequate therapy. In failure revision of diagnosis is necessary, and if the diagnosis of Lyme neuroborreliosis is correct the effects of the therapy should patiently be expected. Relapse or reinfection are confirmed by new raise in titer of specific antibodies, new symptomatology and new antigens.

[Idiopathic normotensive hydrocephalus. Neuropsychologic evaluation after ventriculo-atrial shunt]

Two patients with normal-pressure hydrocephalus were assessed with Luria Nebraska Neuropsychological Battery, before ventriculo-atrial shunting and six months later. The best improvement was recorded in attention, visuospatial and intellectual functions. It is well documented that normal-pressure hydrocephalus dementia can be reversible if proper selection for neurosurgical treatment is made. Cognitive outcome of ventriculo-atrial shunting in normal-pressure hydrocephalus is best assessed with the appropriate neuropsychological testing.