Comparison of MALDI-TOF mass spectrometry and 16S rDNA sequencing for identification of environmental bacteria: a case study of cave mussel-associated culturable microorganisms

Matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) is routinely used as a rapid and cost-effective method for pathogen identification in clinical settings. In comparison, its performance in other microbiological fields, such as environmental microbiology, is still being tested, although isolates of environmental microbes are essential for in-depth in vivo studies of their biology, including biotechnological applications. We investigated the applicability of MALDI-TOF MS for the identification of bacterial isolates from a highly oligotrophic environment - Dinaric Karst caves, which likely harbor specific microorganisms. We cultured bacteria from the shell surface of the endemic mussel Congeria jalzici, one of the three known cave mussels in the world that lives in the Dinaric karst underground. The bacterial isolates were obtained by swabbing the shell surface of mussels living in microhabitats with different amounts of water: 10 air-exposed mussels, 10 submerged mussels, and 10 mussels in the hygropetric zone. A collection of 87 pure culture isolates was obtained, mostly belonging to the phylum Bacillota (72%), followed by Pseudomonadota (16%), Actinomycetota (11%), and Bacteroidota (1%). We compared the results of MALDI-TOF MS identification (Bruker databases DB-5989 and version 11, v11) with the results of 16S rDNA-based phylogenetic analysis, a standard procedure for bacterial identification. Identification to the genus level based on 16S rDNA was possible for all isolates and clearly outperformed the results from MALDI-TOF MS, although the updated MALDI-TOF MS database v11 gave better results than the DB-5989 version (85% versus 62%). However, identification to the species-level by 16S rDNA sequencing was achieved for only 17% of isolates, compared with 14% and 40% for the MALDI-TOF MS databases DB-5989 and v11 database, respectively. In conclusion, our results suggest that continued enrichment of MALDI-TOF MS libraries will result with this method soon becoming a rapid, accurate, and efficient tool for assessing the diversity of culturable bacteria from different environmental niches.

Molecular epidemiology and mechanisms of carbapenem and colistin resistance in Klebsiella and other Enterobacterales from treated wastewater in Croatia

Among the most problematic bacteria with clinical relevance are the carbapenem-resistant Enterobacterales (CRE), as there are very limited options for their treatment. Treated wastewater can be a route for the release of these bacteria into the environment and the population. The aim of this study was to isolate CRE from treated wastewater from the Zagreb wastewater treatment plant and to determine their phenotypic and genomic characteristics. A total of 200 suspected CRE were isolated, 148 of which were confirmed as Enterobacterales by MALDI-TOF MS. The predominant species was Klebsiella spp. (n = 47), followed by Citrobacter spp. (n = 40) and Enterobacter cloacae complex (cplx.) (n = 35). All 148 isolates were carbapenemase producers with a multidrug-resistant phenotype. Using multi-locus sequence typing and whole-genome sequencing (WGS), 18 different sequence types were identified among these isolates, 14 of which were associated with human-associated clones. The virulence gene analysis of the sequenced Klebsiella isolates (n = 7) revealed their potential pathogenicity. PCR and WGS showed that the most frequent carbapenemase genes in K. pneumoniae were blaOXA-48 and blaNDM-1, which frequently occurred together, while blaKPC-2 together with blaNDM-1 was mainly detected in K. oxytoca, E. cloacae cplx. and Citrobacter spp. Colistin resistance was observed in 40% of Klebsiella and 57% of Enterobacter isolates. Underlying mechanisms identified by WGS include known and potentially novel intrinsic mechanisms (point mutations in the pmrA/B, phoP/Q, mgrB and crrB genes) and acquired mechanisms (mcr-4.3 gene). The mcr-4.3 gene was identified for the first time in K. pneumoniae and is probably located on the conjugative IncHI1B plasmid. In addition, WGS analysis of 13 isolates revealed various virulence genes and resistance genes to other clinically relevant antibiotics as well as different plasmids possibly associated with carbapenemase genes. Our study demonstrates the important role that treated municipal wastewater plays in harboring and spreading enterobacterial pathogens that are resistant to last-resort antibiotics.

Treated municipal wastewater as a source of high-risk and emerging multidrug-resistant clones of E. coli and other Enterobacterales producing extended-spectrum β-lactamases

Extended-spectrum β-lactamase (ESBL)-producing Enterobacterales are a major public health problem, and wastewater from municipal wastewater treatment plants (WWTPs) is a potential means of spreading them into the environment and community. Our objective was to isolate ESBL-producing E. coli and other Enterobacterales from wastewater after treatment at Croatia's largest WWTP and to characterize these isolates by phenotypic and genotypic testing. Of the 200 bacterial isolates, 140 were confirmed as Enterobacterales by MALDI-TOF MS, with Escherichia coli and Klebsiella spp. predominating (69% and 7%, respectively). All 140 enterobacterial isolates were multidrug-resistant (MDR) and produced ESBLs. The most prevalent ESBL genes among the isolates tested were blaCTX-M-15 (60%), blaTEM-116 (44%), and blaCTX-M-3 (13%). Most isolates (94%) carried more than one ESBL gene in addition to blaCTX-M. Genes encoding plasmid-mediated AmpC, most notably blaEBC, were detected in 22% of isolates, whereas genes encoding carbapenemases (blaOXA-48, blaNDM-1, blaVIM-1) were less represented (10%). In E. coli, 9 different sequence types (ST) were found, with the emerging high-risk clones ST361 (serotype A-O9:H30) and pandemic ST131 (serotype B2-O25:H4) predominating (32% and 15%, respectively). Other high-risk E. coli clones included ST405 (3%), ST410 (3%), CC10 (3%), ST10 (3%), and ST38 (2%), and emerging clones included ST1193 (2%) and ST635 (2%). Whole-genome sequencing of three representative E. coli from two dominant clone groups (ST361 and ST131) and one extensively drug-resistant K. oxytoca revealed the presence of multiple plasmids and resistance genes to several other antibiotic classes, as well as association of the blaCTX-M-15 gene with transposons and insertion sequences. Our findings indicate that treated municipal wastewater contributes to the spread of emerging and pandemic MDR E. coli clones and other enterobacterial strains of clinical importance into the aquatic environment, with the risk of reintroduction into humans.

Metabolic Associated Fatty Liver Disease (MAFLD) and COVID-19 Infection: An Independent Predictor of Poor Disease Outcome?

Background and Objectives: Early reports on COVID-19 infection suggested that the SARS-CoV-2 virus solely attacks respiratory tract cells. As the pandemic spread, it became clear that the infection is multiorganic. Metabolic associated fatty liver disease (MAFLD) is a chronic liver disease strongly associated with insulin resistance and diabetes. The aim of this study was to assess a possible interplay between MAFLD and COVID-19 infection and its implication in COVID-19 outcome. Materials and Methods: A retrospective observational study, including 130 COVID-19 positive patients was conducted. MAFLD diagnosis was made based on the International Consensus criteria. Patients were divided into two groups, group A (MAFLD) and group B (nonMAFLD). Anthropometric and laboratory analysis were obtained. COVID-19 severity was assessed using the NEWS2 score. Disease outcome was threefold and regarded as discharged, patients who required mechanical ventilation (MV), and deceased patients. Results: MAFLD prevalence was 42%, 67% of patients were discharged, and 19% needed MV. Mortality rate was 14%. MAFLD patients were significantly younger (p < 0.001), and had higher body mass index (p < 0.05), respiratory rate (p < 0.05) and systolic blood pressure (p < 0.05) than nonMAFLD patients. Regarding metabolic syndrome and inflammatory markers: group A had significantly higher glycemia at admission (p = 0.008), lower HDL-c (p < 0.01), higher triglycerides (p < 0.01), CRP (p < 0.001), IL-6 (p < 0.05) and ferritin (p < 0.05) than group B. MAFLD was associated with more prevalent type 2 diabetes (p = 0.035) and hypertension (p < 0.05). MAFLD patients had a more severe disease course (NEWS2 score, 6.5 ± 0.5 vs. 3 ± 1.0, p < 0.05). MAFLD presence was associated with lower patient discharge (p < 0.01) and increased need for MV (p = 0.024). Multiple regression analysis showed that BMI (p = 0.045), IL-6 (p = 0.03), and MAFLD (p < 0.05) are significant independent risk factors for a poor COVID-19 outcome. Conclusions: The prevalence of MAFLD is relatively high. MAFLD patients had a more severe COVID-19 clinical course and worse disease outcome. Our results imply that early patient stratification and risk assessment are mandatory in order to avoid poor outcomes.

Resistance to critically important antibiotics in hospital wastewater from the largest Croatian city

The emergence of extended-spectrum β-lactamase (ESBL)- and especially carbapenemases in Enterobacterales has led to limited therapeutic options. Therefore, it is critical to fully understand all potential routes of transmission, especially in high-risk sources such as hospital wastewater. This study aimed to quantify four enteric opportunistic pathogens (EOPs), total, ESBL- and carbapenem-resistant coliforms and their corresponding resistance genes (two ESBL and five carbapenemase genes) and to characterize enterobacterial isolates from hospital wastewater from two large hospitals in Zagreb over two seasons. Culturing revealed similar average levels of total and carbapenem-resistant coliforms (3.4 × 10⁴ CFU/mL), and 10-fold lower levels of presumptive ESBL coliforms (3 × 10³ CFU/mL). Real-time PCR revealed the highest E. coli levels among EOPs (10⁵ cell equivalents/mL) and the highest levels of the bla_KPC gene (up to 10^-1 gene copies/16S copies) among all resistance genes examined. Of the 69 ESBL- and 90 carbapenemase-producing Enterobacterales (CPE) isolates from hospital wastewater, all were multidrug-resistant and most were identified as Escherichia coli, Citrobacter, Enterobacter, and Klebsiella. Among ESBL isolates, bla_CTX-M-15 was the most prevalent ESBL gene, whereas in CPE isolates, bla_KPC-2 and bla_NDM-1 were the most frequently detected CP genes, followed by bla_OXA-48. Molecular epidemiology using PFGE, MLST and whole-genome sequencing (WGS) revealed that clinically relevant variants such as E. coli ST131 (bla_CTX-M-15/bla_TEM-116) and ST541 (bla_KPC-2), K. pneumoniae ST101 (bla_OXA-48/bla_NDM-1), and Enterobacter cloacae complex ST277 (bla_KPC-2/bla_NDM-1) were among the most frequently detected clone types. WGS also revealed a diverse range of resistance genes and plasmids in these and other isolates, as well as transposons and insertion sequences in the flanking regions of the bla_CTX-M, bla_OXA-48, and bla_KPC-2 genes, suggesting the potential for mobilization. We conclude that hospital wastewater is a potential secondary reservoir of clinically important pathogens and resistance genes and therefore requires effective pretreatment before discharge to the municipal sewer system.

Prevalence of HEV RNA in Croatian blood donors

OBJECTIVES

HEV infection is asymptomatic for immunocompetent blood donors (BD). Transfused HEV-infected blood products may cause potentially hazardous HEV infection in immunocompromised patients. Evaluation of the need for routine BD HEV RNA screening primarily demands the establishment of HEV infection prevalence in Croatian BD.

MATERIALS AND METHODS

We tested BD samples in ID-NAT with the Procleix UltrioPlex E screening test for simultaneous detection of HBV DNA, HCV RNA, HIV-1,2 RNA, and HEV RNA (Grifols, Spain). HEV infection was confirmed with HEV RNA quantitative test (Altona Diagnostics, Germany) and HEV IgM and HEV IgG antibody test (DIA.PRO Diagnostic Bioprobes, Italy). We analysed the HEV RNA sequence and performed a phylogenetic analysis. We recorded BD's anamnestic data and dietary habits. BDs gave follow-up samples after two months and did not donate blood for six months.

RESULTS

Between December 2021 and March 2022, we tested 8,631 donations and found four HEV RNA-positive donations, which equals to one in 2,158 donations (0.046 %, 95 % confidence interval, 0.018 %-0.119 %). Confirmatory HEV RNA testing gave results from negative to 4.73E + 3 IU/ml HEV RNA. Three donations were in the serological window period. We have genotyped HEV RNA of two infected BD as genotype HEV-3c. Blood donors didn't report any health problems and their diet included pork. Testing on follow-up samples presented seroconversion and no HEV RNA could be detected.

CONCLUSION

The incidence of HEV RNA infection in BD in Croatia corresponds with other European data. The decision on implementation of HEV NAT screening in Croatia needs an expert team evaluation of the possible risk of TT-HEV infection.

Prevalence of enteric opportunistic pathogens and extended-spectrum cephalosporin- and carbapenem-resistant coliforms and genes in wastewater from municipal wastewater treatment plants in Croatia

Extended-spectrum β-lactamase (ESBL)- and carbapenemase-producing Enterobacterales are a critical global health problem and wastewater treatment plants (WWTPs) can promote their spread into the environment; yet their efficacy is not well characterized. Here, we have used conventional culturing to monitor coliform bacteria and quantitative PCR to monitor 2 ESBL and 5 carbapenemase (CP) genes and 4 enteric opportunistic pathogens (EOPs) in the influent and effluent of 7 Croatian WWTPs in two seasons. In general, levels of total, cefotaxime- and carbapenem-resistant coliforms were significantly reduced but not eliminated by conventional treatment in most WWTPs. Most WWTPs efficiently removed EOPs such as K. pneumoniae and A. baumannii, while E. coli and Enterococcus spp. were reduced but still present in relatively high concentrations in the effluent. ESBL genes (bla_TEM and bla_CTX-M-32) were only slightly reduced or enriched after treatment. CP genes, bla_KPC-3, bla_NDM and bla_OXA-48-like, were sporadically detected, while bla_IMP and bla_VIM were frequently enriched during treatment and correlated with plant size, number or size of hospitals in the catchment area, and COD effluent concentration. Our results suggest that improvements in wastewater treatment technologies are needed to minimize the risk of environmental contamination with top priority EOPs and ARGs and the resulting public health.

Prenatal RHD genotyping in Croatia: preliminary results

OBJECTIVES

Croatian Institute of Transfusion Medicine (CITM) implemented non-invasive fetal RHD genotyping as a request for targeted antenatal anti-D prophylaxis. The diagnostic performance of in-house RT-PCR method for fetal RHD genotyping and preliminary results are analyzed.

MATERIALS AND METHODS

Evaluation included results of RHD genotyping for 205 RhD negative pregnant women, 12-36th week of gestation, whose samples were received in period between 2015 and 2020. QIAsymphony SP DSP Virus Midi Kit was used for cffDNA extraction on QIAsymphony SP platform (Qiagen, Germany). Fragments of RHD exons 7 and 10 and later exon 5 were RT-PCR amplified. As internal controls, amplification of SRY gene or RASSF1A fragment and β-actin genes digested with BsTUI were used.

RESULTS

We identified 70.72% (145/205) positive and 28.78% (59/205) negative fetal RHD genotypes. We had one inconclusive result (0.50%) due to the interference of maternal DNA with variant genotype RHD*09.02.00/01/*01N.01. When compared to newborns RhD phenotypes, no false negative and three false positive results (3/199, 1.50%) were observed. The test yielded 100% sensitivity and 95.08% specificity, while diagnostic accuracy was 98.48%. We were able to determine one case of fetal variant genotype RHD*04.04/*01N.01 inherited from the father. The negative and positive predictive test values were 100% and 97.86%, respectively.

CONCLUSION

Automated cffDNA extraction and RT-PCR amplification of fetal RHD exons 5,7,10 and fragments of SRY, RASSF1A genes represents highly reliable system for determining fetal RHD status which enables targeted antenatal anti-D prophylaxis. To obtain high specificity of cffDNA extraction, strict and thoroughly cleaning procedures are required.

Anti-HBc prevalence among Croatian blood donors in a 14-year period (2004-2017): Assessment of trends, risks and need for implementing routine testing

OBJECTIVES

The anti-HBc prevalence over a 14-years period (2004-2017), trends, infectivity, residual risk, and need for testing in blood donors (BD) of the Croatian Institute of Transfusion Medicine were assessed.

MATERIAL AND METHODS

Anti-HBc was tested in 19,969 BD serum samples collected in 2004 (N=7561), 2013 (N=7318) and 2017 (N=5090). All serums were initially screened for HBsAg, anti-HCV, HIV Ag/Ab, and anti-TP. 2013 and 2017 samples were also tested by ID-NAT.

RESULTS

Over a 14-years period, the anti-HBc prevalence significantly decreased among Croatian BD (5.24% in 2004, 2.56% in 2013, and 1.32% in 2017). Similarly, the prevalence of anti-HBc-only profiles decreased from 0.62% in 2004, 0.25% in 2013, and 0.21% in 2017. The 4-time decreasing trend was observed in all age groups of BD from 2017 but mostly among repeat donors (5.90% to 1.38%). First-time donors showed no significant difference in anti-HBc prevalence probably due to their younger age (<29 years) and HBV vaccine status. However, similar anti-HBs carriage rates (80.56%, 87.57%, and 82.09%) were reported in anti-HBc positive donors over the study period. HBsAg and HBV DNA were not detected. No OBI infection was found in the study despite an OBI frequency of 1:10,900 donations previously reported in Croatia. A HBV decreasing residual risks of 68, 88, and 12 per million donations were estimated for years 2004, 2013, and 2017, respectively.

CONCLUSION

Anti-HBc testing is an additional measure of preventing HBV infection by transfusion. Implementation of anti-HBc testing will result in the deferral of 1.3% BD and should be supported by cost-benefit analyses.

Distribution and diversity of marine picocyanobacteria community: Targeting of Prochlorococcus ecotypes in winter conditions (southern Adriatic Sea)

Adriatic, the northernmost part of the Mediterranean Sea, due its oligotrophy, topography, and hydrology dynamics, and complex circulation patterns, was suggested as an important study site for rapid climatology impacts. Its southern part is mainly oligotrophic and dominated by picophytoplankton, with cyanobacteria as main representatives. Diversity and distribution patterns of different Prochlorococcus ecotypes were investigated by molecular tools and flow cytometry during the winter convection event in the southern Adriatic (BIOTA winter cruise; February/March 2015). Phylogenetic diversity based on clone libraries of the 16S-23S ribosomal DNA ITS region, as well as flow cytometry (histograms of red fluorescence), indicated presence of 2 different Prochlorococcus in the Adriatic. HLI, as a typical clade for Mediterranean Sea, was likewise found to be dominant Prochlorococcus in the Adriatic, followed by less abundant LLI clade. In addition, Prochlorococcus were found to co-occur with diverse Synechococcus population (53% and 47% of obtained ITS sequences, respectively). Different Prochlorococcus ecotypes had similar patterns of vertical distribution, predominantly occupying upper 100m depth layer, but their distribution was clearly affected by the heterogeneity of hydrological conditions, nitrogen concentration and temperature along vertical and horizontal sampling points. Different studies pointed out that, as a consequence of climate changes, serious alteration of biological and ecological patterns are already taking place Therefore, understanding of the distribution and abundance of picophytoplankton in Adriatic, being still limited, is much needed baseline for predicting possible biogeochemical impact of future environmental changes.

Quantitative Analysis of Phenolic Acids and Antiplatelet Activity of Melissa officinalis Leaf Extracts

The contents of total phenolic acids and rosmarinic acid were determined and the antiplatelet potential assessed of extracts of lemon balm ( Melissa officinalis L., Lamiaceae) leaf samples collected during 2014 and 2015. The quantity of total phenolic acids ranged from 4.8 to 8.5%, while the rosmarinic acid content ranged from 1.78 to 4.35%. Results of statistical analysis showed that the undiluted extracts have antiplatelet activity in the ADP test (final concentration 31.25 mg/L). While there are reports on antiplatelet activity of lemon balm essential oil, to the best of our knowledge, this is the first report on antiplatelet activity of lemon balm leaf extracts.

Quantitative Analysis of Phenolic Acids and Antiplatelet Activity of Melissa officinalis Leaf Extracts

The contents of total phenolic acids and rosmarinic acid were determined and the antiplatelet potential assessed of extracts of lemon balm (Melissa officinalis L., Lamiaceae) leaf samples collected during 2014 and 2015. The quantity of total phenolic acids ranged from 4.8 to 8.5%, while the rosmarinic acid content ranged from 1.78 to 4.35%. Results of statistical analysis showed that the undiluted extracts have antiplatelet activity in the ADP test (final concentration 31.25 mg/L). While there are reports on antiplatelet activity of lemon balm essential oil, to the best of our knowledge, this is the first report on antiplatelet activity of lemon balm leaf extracts.

The importance of combined 24-hour multichannel intraluminal impedance-pH monitoring in the evaluation of children with suspected laryngopharyngeal reflux

OBJECTIVE

The aim of this study was to investigate the diagnostic usefulness of combined multichannel intraluminal impedance-pH (MII-pH) monitoring in children with suspected laryngopharyngeal reflux (LPR).

DESIGN, SETTING AND PARTICIPANTS

A prospective study including children in whom, due to LPR suggestive symptoms, MII-pH monitoring was performed at tertiary medical centre from February 2012 to July 2015.

INTERVENTIONS

All included children underwent same diagnostic protocol which included examination by single pulmonologist and ENT specialist and underwent 24-hour MII-pH monitoring.

MAIN OUTCOMES

Primary outcome was to determine MII-pH characteristics of the children in whom LPR was suspected based on symptoms and ENT examination.

RESULTS

One hundred and four patients (mean age 8.9 years; range 0.4-17.9 years; male/female 57/47) participated in the study. In children with signs and symptoms suggestive of LPR, MII-pH monitoring found the median incidence of proximal gastro-oesophageal reflux (GER) of 15 (range 0-129), proximal acidic GER of 6.5 (range 0-66) and weakly acidic GER of 5 (range 0-102). There were significant positive correlations between the number of GER (proximal total, acidic and weakly acid) with Reflux Finding Score, Reflux Symptom Index and presence of eosinophils in nasal swabs. The only endoscopy ENT finding which significantly correlated with total proximal GER, acid proximal GER and weakly acidic proximal GER was arytenoid hyperaemia.

CONCLUSION

Both acid and non-acid reflux seem to have a significant role in the pathogenesis of LPR.

Trends in family planning and contraception carried out in primary health care in Croatia: 1995-2012: study based on routinely collected data

The lack of objective findings provided the reason to undertake this study with the main aim of exploring the trends in family planning and contraception carried out in primary health care in Croatia. Based on the Croatian health statistical yearbooks from 1995 to 2012, data were collected on the number and structure of visits and the number and type of prescribed contraceptives by public and private gynecological practices, and visits to family practices and school medicine services. The results showed that only a small number of fertile women received primary care for family planning issues, trends that are evident through the entire follow-up period. A trend of "migration" from the public to the private sector is also observed. Family doctors and school medicine are almost entirely excluded from the provision of family planning despite the magnitude of the family planning problem resulting in a waste of human and material resources.

Rejecting a general check-up: case report

65-old gentleman rejected the general check-up recommendation, because he felt healthy. As his chosen family doctor, I also perceive him as the healthy patient, not having any risks. In spite of my personal concerns, it was obvious that I had to respect his choice, because of Act on Patients Rights and the Physicians Ethical Code. But, at that moment I was not certain about the evidence on the effectiveness of general chech-ups and some professional dilemmas remain. Therefore, we did a limited literature search. A Cochrane systematic analysis as well as other systematic reviews has shown that there is no evidence on the effectiveness of general check-ups. In the professional recommendations general check-ups are replaced by preventive measures with proven effectiveness, such as those recommended by the Canadian Task Force on Preventive Health Care and the U.S. Preventive Task Force. It helps me to solve my professional dilemmas around this patient.

Trends in preventive activities for the adult population in family medicine in Croatia: 1995-2012

A few preventive activities were recorded in Croatian family medicine (FM) from 1995 until 2003, and then in 2004, additional fee-for-service reimbursement for general check-ups for people aged 45 to 65 years was introduced. The aim of this study was to investigate the trends in preventive activities before and after the introduction of those measures by using the Croatian Health Service Yearbooks for 1995-2012 as the main database. Data on the number of preventive, general, and total number of check-ups were collected. The results showed that the total number of check-ups registered in FM was low, suggesting that the additional reimbursement did not bring any improvements. In fact, the trend in the number decreased after 2004. These results are not unexpected because of the ineffectiveness of general check-ups as indicated in the literature. General check-ups should be replaced by targeted preventive interventions with evidence-based effectiveness.

Mammography Screening--how persistent should we be in the recommendations?

55 year old women came to me as her family doctor, seeking advice on mammography screening. She rather wouldn't do it because she feels well, is a bit afraid of radiation and thinks it's not important, since she doesn't have individual risk. Having in mind newly emerging evidence about the questionable value of the screening, especially in women without any risks, I was in dilemma what to recommend. Therefore, we did a limited literature search. Systematic reviews are questioning effectiveness of mammography as screening method, evidences show limited effect on reducing mortality and the burden of overdiagnosis and overtreatmnent. Professional recommendations vary from country to country. Overall impression is that many questions remain open and, until better method of screening is found, the decisions about breast cancer screening should be strongly individualized, according to the patients risks. We openly discussed it, she decided to postpone mammography for a while.

Identification and characterization of potential autochthonous starter cultures from a Croatian "brand" product "Slavonski kulen"

The microbial population of a traditional Croatian fermented sausage "Slavonski kulen" was isolated, identified and subjected to technological and functional characterization in order to select potential autochthonous functional starter cultures. Dominant microflora were lactic acid bacteria (LAB), followed by staphylococci. Identification of isolated lactobacilli showed domination of Leuconostoc mesenteroides and Lactobacillus acidophilus while Staphylococcus xylosus and Staphylococcus warneri outnumbered the staphylococcal microbiota. Most of the isolated LAB and Staphylococcus species displayed good growth in the presence of 5% of NaCl and at 12, 18 and 22°C. All LAB and most of the staphylococci possess proteolytic activity and only Staphylococcus xylosus had lipolytic activity. All lactobacilli and staphylococci isolates produced significant concentrations of lactic acid (as determined by HPLC) and showed antimicrobial activity against pathogenic test microorganisms. Dominant LAB and Staphylococcus species displayed growth in the presence of 1% bile. Most of the staphylococci and all of lactobacilli showed sensitivity to all antibiotics tested.

Severe psychomotor retardation in a boy with a small supernumerary marker chromosome 19p

We describe the clinical case of a nine-year-old boy with psychomotor retardation and a small supernumerary marker chromosome (sSMC) present in mosaic form. Fluorescence in situ hybridization (FISH) using centromere cross-hybridizing probes D1/5/19Z (pZ5.1), the whole chromosome paint probe 19, pool YACs19p (839B1, 872G3, 728C8), and pool YACs19q (767C4, 761C1, 786G6) demonstrated that the sSMC was derived from chromosome 19p. Based on GTG-banding and FISH analyses, the patient's karyotype was interpreted as: 47,XY,+mar.ish der(19) (:p13.3-->p11:)(839B1+, 872G3+,728C8+, D1/5/19Z+) de novo[52]/46,XY[48]. To our knowledge, only two other similar cases have been reported. This case helps to better delineate karyotype-phenotype correlations between sSMC 19p and associated clinical phenomena.

Prenatal diagnosis of complete trisomy 19q

This communication presents the first case of complete trisomy 19q, prenatally detected by ultrasound investigation. Real-time high-resolution ultrasound examination was performed at 19 weeks of gestation. After termination of the pregnancy, autopsy investigation was done. GTG-banding, fluorescence in situ hybridization m-(FISH) analysis, and FISH analysis with a 19q subtelomeric specific probe were used for identification of the fetal karyotype. Sonographic examination revealed an enlarged cisterna magna, cerebellar hypoplasia and aplasia of the inferior part of the vermis, combined and bilateral kidney malformations, significant nuchal fold, absence of fetal nasal bones, and intracardial calcifications. Autopsy confirmed ultrasound findings, but also revealed situs viscerum inversus of the lungs. Fetal karyotype was defined as: 46,XY,der(21)t(19;21)(q11;p13)mat. Our ultrasound and autopsy findings will certainly contribute to better knowledge of phenotype characterization of this rare chromosomal disorder.

Clinical validation of bronchial hyperresponsiveness, allergy tests and lung function in the diagnosis of asthma in persons with dyspnea

The aim of the study was to determine the most useful tests for decision making in the diagnosis of asthma in patients with dyspnea assessed by commonly used terms: sensitivity, specificity, positive and negative predictive values and diagnostic accuracy. In a group of 195 patients with dyspnea data were analyzed with respect to case histories and different diagnostic procedures: bronchial hyperresponsiveness (BHR), skin prick tests (SPT), total IgE, spirometry (FEV1), sputum eosinophils (SE) and blood eosinophilia (BE). Asthma was diagnosed in 141 subjects. The control group comprised 18 subjects. Sensitivity for BHR in asthma in subjects with dyspnea amounted to 97%, for SPT to 62%, while all other diagnostics were lower than 50%. Specificity was highest for SE (94%), and BHR (85%). Positive predictive value (PPV) in asthma was for BHR 94%, for SE 86%, for SPT 81%, for decreased FEV1 79%, total IgE 72% and BE 64%. The highest negative predictive value (NPV) was found for BHR (92%). Diagnostic accuracy was highest for BHR 93% and for SPT 62%, while all other tests were comparable or lower than 50%. It is not possible to conclude whether or not a person has asthma merely on the basis of data on skin sensitization to aeroallergens, total IgE, eosinophils or lung function tests. Bronchial hyperresponsiveness showed the highest values for sensitivity (97%), PPV (94%), NPV (92%) and accuracy (93%). The second most efficient test is the skin prick test, with PPV 81% and diagnostic accuracy 62%.

[Correlation of the size of the residual volume measured by whole body plethysmography and the single breath helium dilution method]

The value of residual volume, intrathoracic gas volume, functional residual capacity and total lung capacity obtained by the method of body plethysmography and helium dilution method was correlated by single-breath diffusing capacity. These parameters were correlated in 22 patients who had had complete functional diagnostics of the lung: spirometry, flow volume curve, body plethysmography and single-breath diffusing capacity. All findings were within normal limits, which was a condition for selection of patients for our group. Statistically significant differences (p = 0.01) of t-test were established between residual volumes by the plethysmographic and helium dilution method of single-breath diffusing capacity. The residual volume obtained by body plethysmography showed higher values for 526 ml, or 30%. The intrathoracic gas volume showed higher values for 682 ml, or 17%. Inspite of the fact that values of RV obtained by two methods had statistically significant differences, they were still within normal limits, if presented as percent of the predicted value.

[The frequency of bacteriuria in pregnancy]

The authors present the results of a bacteriological urine analysis of 1774 pregnant women controlled in the Gynecological Dispensary Pesćenica in Zagreb. In 2824 examined urine specimens sterile urinocultures were found in 67.6% and bacteriuria in 32.4%. Significant findings of bacteriuria were recorded in 10.5% and insignificant ones in 21.9% of the specimens. The most common bacteria were E. coli (45.24%), then Staphylococcus albus epidermidis (17.4%), Staphylococcus pyogenes aureus (14.64%), Proteus mirabilis (9.39%), and Enterococcus (5.24%). Urine specimens were taken by the dip slide method. A rather high percentage of significant asymptomatic bacteriurias (10.5%) suggests the early detection and therapy in urinary infections as the best prevention of pyelonephritis gravidarum and gestosis. A routine bacteriological urine analysis in pregnant women should be one of the factors included in prenatal care.