Jana Lozar Krivec
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Jana Lozar Krivec has a total of 41 co-authors. Here are the top co-authors by number of shared publications:
Darja Paro-Panjan
Department of Neonatology, University Children’s Hospital, University Medical Centre Ljubljana; Faculty of Medicine, University of Ljubljana, Ljubljana
2 shared publications- Darja Paro-Panjan
Department of Neonatology, University Children’s Hospital, University Medical Centre Ljubljana, 1000 Ljubljana, Slovenia
2 shared publications A. Mahnič
Department for Microbiological Research, National Laboratory for Health, Environment and Food, Prvomajska ulica 1, Maribor, Slovenia
1 shared publicationA. PetrovčiČ
Faculty of Social Sciences, University of Ljubljana, Kardeljeva Ploščad 5, Ljubljana, Slovenia
1 shared publicationA. Valcl
Department of Pediatrics, https://dx.doi.org/37672General Hospital Slovenj Gradec, Gosposvetska ulica 3, Slovenj Gradec, Slovenia
1 shared publication- Aleksander Mahnič
Department for Microbiological Research, National Laboratory for Health, Environment and Food, 2000 Maribor, Slovenia
1 shared publication
Latest Publications
- Open Access
Probiotic Supplementation to Prevent Diaper Dermatitis in Antibiotic-Treated Neonates: Secondary Analysis of a Randomised Controlled Trial
Background/Objectives: Diaper dermatitis (DD) is a common dermatological condition that is often exacerbated by antibiotics. Probiotics may restore microbiota balance and influence the incidence of DD. This study aimed to evaluate whether 6 weeks of Limosilactobacillus (L.) reuteri DSM 17938 supplementation during and after antibiotic treatment affects the incidence of DD. Methods: A secondary analysis of a randomised, double-blind, placebo-controlled trial that included 89 term neonates treated with antibiotics during the first 3 weeks of life was conducted. Neonates were assigned to receive either a probiotic supplement or a placebo for a total of 6 weeks. DD incidence, onset of DD, and skin care data were collected for 87 infants. Faecal samples were collected 6 weeks after study enrolment to analyse the composition of gut microbiota. Results: Twenty-four (28%) infants developed DD, of whom six (25%) had fungal DD. There was no significant difference in the incidence of DD or fungal DD between the probiotic and placebo groups (30% vs. 25% and 7% in both groups, respectively). Probiotic supplementation had no significant effect on the gut microbiota composition or diversity. In an exploratory binary logistic regression analysis based on six fungal DD events, probiotic supplementation was not associated with fungal DD, whereas breastfeeding was associated with lower odds of fungal DD; however, the overall model was not statistically significant, and this finding should be interpreted with caution because of the small number of events. Conclusions: In this exploratory secondary analysis, supplementation with L. reuteri DSM 17938 was not associated with a reduced incidence of DD or alterations in gut microbiota composition in antibiotic-treated neonates. Breastfeeding was associated with lower odds of fungal DD; however, this finding should be confirmed in larger, adequately powered studies.
Open AccessProbiotic Supplementation to Prevent Diaper Dermatitis in Antibiotic-Treated Neonates: Secondary Analysis of a Randomised Controlled Trial
Background/Objectives: Diaper dermatitis (DD) is a common dermatological condition that is often exacerbated by antibiotics. Probiotics may restore microbiota balance and influence the incidence of DD. This study aimed to evaluate whether 6 weeks of Limosilactobacillus (L.) reuteri DSM 17938 supplementation during and after antibiotic treatment affects the incidence of DD. Methods: A secondary analysis of a randomised, double-blind, placebo-controlled trial that included 89 term neonates treated with antibiotics during the first 3 weeks of life was conducted. Neonates were assigned to receive either a probiotic supplement or a placebo for a total of 6 weeks. DD incidence, onset of DD, and skin care data were collected for 87 infants. Faecal samples were collected 6 weeks after study enrolment to analyse the composition of gut microbiota. Results: Twenty-four (28%) infants developed DD, of whom six (25%) had fungal DD. There was no significant difference in the incidence of DD or fungal DD between the probiotic and placebo groups (30% vs. 25% and 7% in both groups, respectively). Probiotic supplementation had no significant effect on the gut microbiota composition or diversity. In an exploratory binary logistic regression analysis based on six fungal DD events, probiotic supplementation was not associated with fungal DD, whereas breastfeeding was associated with lower odds of fungal DD; however, the overall model was not statistically significant, and this finding should be interpreted with caution because of the small number of events. Conclusions: In this exploratory secondary analysis, supplementation with L. reuteri DSM 17938 was not associated with a reduced incidence of DD or alterations in gut microbiota composition in antibiotic-treated neonates. Breastfeeding was associated with lower odds of fungal DD; however, this finding should be confirmed in larger, adequately powered studies.
- Open Access
- 31 October 2024
- Published by Walter de Gruyter GmbH in Beneficial Microbes
- Vol. 16 (2) , 157-169
Effects of Limosilactobacillus reuteri DSM 17938 in neonates exposed to antibiotics: a randomised controlled trial
Perinatal antibiotic exposure potentially leads to gut microbiota dysbiosis, which is associated with functional gastrointestinal disorders (FGIDs). We aimed to investigate the effects of Limosilactobacillus reuteri DSM 17938 supplementation on the development of FGIDs, crying and sleep duration, and the gut microbial composition in infants exposed to antibiotics during the neonatal period. In this randomised, double-blind, placebo-controlled study, we included 89 term neonates treated with antibiotics. Neonates received the study product for six weeks. FGIDs, assessed by the Infant Gastrointestinal Symptom Questionnaire, crying and sleep duration were assessed at four and eight weeks, and six months after enrolment. Faecal samples were collected six weeks and twelve months after enrolment. The gut microbial community composition was analysed using 16S amplicon sequencing and qPCR. The proportion of infants with FGIDs was greater in the control group, although the difference between the groups was significant only six months after enrolment. At all time points, the probiotic group presented a longer sleep duration and shorter crying time than the control group, but the difference was not statistically significant. Probiotic consumption had no significant effect on the gut microbiota composition except for increased L. reuteri DSM 17938 abundance in the probiotic group at six weeks after enrolment. At specific time points after supplementation with L. reuteri DSM 17938, a reduction in the prevalence of FGIDs was observed in the probiotic group. However, no observable effect on the gut microbiota was detected during the intervention. We believe that probiotic supplementation in neonates during and after antibiotic treatment to minimise the negative effects of antibiotics on gut function during this vulnerable period of human development warrants further investigation. The trial is registered at ClinicalTrials.gov (NCT02865564)
- 31 October 2024
- Published by Walter de Gruyter GmbH in Beneficial Microbes
- Vol. 16 (2) , 157-169
Open AccessEffects of Limosilactobacillus reuteri DSM 17938 in neonates exposed to antibiotics: a randomised controlled trial
Perinatal antibiotic exposure potentially leads to gut microbiota dysbiosis, which is associated with functional gastrointestinal disorders (FGIDs). We aimed to investigate the effects of Limosilactobacillus reuteri DSM 17938 supplementation on the development of FGIDs, crying and sleep duration, and the gut microbial composition in infants exposed to antibiotics during the neonatal period. In this randomised, double-blind, placebo-controlled study, we included 89 term neonates treated with antibiotics. Neonates received the study product for six weeks. FGIDs, assessed by the Infant Gastrointestinal Symptom Questionnaire, crying and sleep duration were assessed at four and eight weeks, and six months after enrolment. Faecal samples were collected six weeks and twelve months after enrolment. The gut microbial community composition was analysed using 16S amplicon sequencing and qPCR. The proportion of infants with FGIDs was greater in the control group, although the difference between the groups was significant only six months after enrolment. At all time points, the probiotic group presented a longer sleep duration and shorter crying time than the control group, but the difference was not statistically significant. Probiotic consumption had no significant effect on the gut microbiota composition except for increased L. reuteri DSM 17938 abundance in the probiotic group at six weeks after enrolment. At specific time points after supplementation with L. reuteri DSM 17938, a reduction in the prevalence of FGIDs was observed in the probiotic group. However, no observable effect on the gut microbiota was detected during the intervention. We believe that probiotic supplementation in neonates during and after antibiotic treatment to minimise the negative effects of antibiotics on gut function during this vulnerable period of human development warrants further investigation. The trial is registered at ClinicalTrials.gov (NCT02865564)
- Open Access
- 21 December 2023
- Published by University Clinical Centre Tuzla in Central European Journal of Paediatrics
- Vol. 19 (2) , 127-136
The Diagnostic Value of Lung Ultrasound in Neonates and Infants with Acute Bronchiolitis
Objective − We analysed the relationship between the lung ultrasound (LUS) score and clinical characteristics in order to evaluate the diagnostic and predictive value of LUS in neonates and infants with acute bronchiolitis. Subjects and Methods − Term infants aged up to 3 months, admitted to Ljubljana University Children’s Hospital due to acute bronchiolitis in the period from January to April 2020, were studied prospectively. LUS score and clinical assessment score (CAS) were determined upon admission. The patients were divided into groups according to LUS score and CAS. Clinical and laboratory characteristics were compared between the groups. Correlations between LUS score, duration of clinical signs prior to admission, CAS and partial carbon dioxide pressure in the capillary blood (PCO2) upon admission, length of hospitalization and duration of supplemental oxygen (O2) therapy were analysed. Additionally, the predictive value of LUS and CAS for the need of non-invasive respiratory support (NRS) was calculated. Results − The LUS score correlated with the clinical severity of acute bronchiolitis. Patients with higher LUS score had higher CAS (PConclusions − Larger studies are needed to evaluate the predictive and diagnostic value of LUS in neonates and young infants with acute bronchiolitis.
- 21 December 2023
- Published by University Clinical Centre Tuzla in Central European Journal of Paediatrics
- Vol. 19 (2) , 127-136
Open AccessThe Diagnostic Value of Lung Ultrasound in Neonates and Infants with Acute Bronchiolitis
Objective − We analysed the relationship between the lung ultrasound (LUS) score and clinical characteristics in order to evaluate the diagnostic and predictive value of LUS in neonates and infants with acute bronchiolitis. Subjects and Methods − Term infants aged up to 3 months, admitted to Ljubljana University Children’s Hospital due to acute bronchiolitis in the period from January to April 2020, were studied prospectively. LUS score and clinical assessment score (CAS) were determined upon admission. The patients were divided into groups according to LUS score and CAS. Clinical and laboratory characteristics were compared between the groups. Correlations between LUS score, duration of clinical signs prior to admission, CAS and partial carbon dioxide pressure in the capillary blood (PCO2) upon admission, length of hospitalization and duration of supplemental oxygen (O2) therapy were analysed. Additionally, the predictive value of LUS and CAS for the need of non-invasive respiratory support (NRS) was calculated. Results − The LUS score correlated with the clinical severity of acute bronchiolitis. Patients with higher LUS score had higher CAS (PConclusions − Larger studies are needed to evaluate the predictive and diagnostic value of LUS in neonates and young infants with acute bronchiolitis.
- Open Access
- 1 January 2023
- Published by The Korean Society of Pediatric Gastroenterology, Hepatology and Nutrition in Pediatric Gastroenterology, Hepatology & Nutrition
- Vol. 26 (1) , 70-77
Treatment of Symptomatic Focal Hepatic Hemangioma with Propranolol in Neonates: Is It Efficient?
Lozar Krivec J, et al. Pediatr Gastroenterol Hepatol Nutr. 2023 Jan;26(1):70-77. https://doi.org/10.5223/pghn.2023.26.1.70
- 1 January 2023
- Published by The Korean Society of Pediatric Gastroenterology, Hepatology and Nutrition in Pediatric Gastroenterology, Hepatology & Nutrition
- Vol. 26 (1) , 70-77
Open AccessTreatment of Symptomatic Focal Hepatic Hemangioma with Propranolol in Neonates: Is It Efficient?
Lozar Krivec J, et al. Pediatr Gastroenterol Hepatol Nutr. 2023 Jan;26(1):70-77. https://doi.org/10.5223/pghn.2023.26.1.70
- 26 April 2022
- Published by SAGE Publications in Journal of Neonatology
- Vol. 36 (3) , 246-249
Myositis Ossificans Mimicking Soft Tissue Infection in a Neonate—A Case Report
Myositis ossificans is characterized by heterotopic bone formation in skeletal muscle that may present as a tender, warm, palpable swelling, and mimicking soft tissue infection. We present the clinical and imaging evolution of the disease with a favorable outcome in a preterm baby with complicated postnatal course.
- 26 April 2022
- Published by SAGE Publications in Journal of Neonatology
- Vol. 36 (3) , 246-249
Myositis Ossificans Mimicking Soft Tissue Infection in a Neonate—A Case Report
Myositis ossificans is characterized by heterotopic bone formation in skeletal muscle that may present as a tender, warm, palpable swelling, and mimicking soft tissue infection. We present the clinical and imaging evolution of the disease with a favorable outcome in a preterm baby with complicated postnatal course.
- Open Access
- 16 December 2020
- Published by Springer Nature in BMC Infectious Diseases
- Vol. 20 (1) , 1-9
Genomic and phenotypic characterisation of invasive neonatal and colonising group B Streptococcus isolates from Slovenia, 2001–2018
Background: Group B Streptococcus (GBS) is the leading cause of invasive neonatal disease in the industrialized world. We aimed to genomically and phenotypically characterise invasive GBS isolates in Slovenia from 2001 to 2018 and contemporary colonising GBS isolates from screening cultures in 2018. Methods: GBS isolates from 101 patients (invasive isolates) and 70 pregnant women (colonising isolates) were analysed. Basic clinical characteristics of the patients were collected from medical records. Antimicrobial susceptibility and phenotypic capsular serotype were determined. Whole-genome sequencing was performed to assign multilocus sequence types (STs), clonal complexes (CCs), pathogenicity/virulence factors, including capsular genotypes, and genome-based phylogeny. Results: Among invasive neonatal disease patients, 42.6% (n = 43) were females, 41.5% (n = 39/94) were from preterm deliveries (< 37 weeks gestation), and 41.6% (n = 42) had early-onset disease (EOD). All isolates were susceptible to benzylpenicillin with low minimum inhibitory concentrations (MICs; ≤0.125 mg/L). Overall, 7 serotypes were identified (Ia, Ib, II-V and VIII); serotype III being the most prevalent (59.6%). Twenty-eight MLST STs were detected that clustered into 6 CCs. CC-17 was the most common CC overall (53.2%), as well as among invasive (67.3%) and non-invasive (32.9%) isolates (p < 0.001). CC-17 was more common among patients with late-onset disease (LOD) (81.4%) compared to EOD (47.6%) (p < 0.001). The prevalence of other CCs was 12.9% (CC-23), 11.1% (CC-12), 10.5% (CC-1), 8.2% (CC-19), and 1.8% (CC-498). Of all isolates, 2.3% were singletons. Conclusions: A high prevalence of hypervirulent CC-17 isolates, with low genomic diversity and characteristic profile of pathogenicity/virulence factors, was detected among invasive neonatal and colonising GBS isolates from pregnant women in Slovenia. This is the first genomic characterisation of GBS isolates in Slovenia and provides valuable microbiological and genomic baseline data regarding the invasive and colonising GBS population nationally. Continuous genomic surveillance of GBS infections is crucial to analyse the impact of IND prevention strategies on the population structure of GBS locally, nationally, and internationally.
- 16 December 2020
- Published by Springer Nature in BMC Infectious Diseases
- Vol. 20 (1) , 1-9
Open AccessGenomic and phenotypic characterisation of invasive neonatal and colonising group B Streptococcus isolates from Slovenia, 2001–2018
Background: Group B Streptococcus (GBS) is the leading cause of invasive neonatal disease in the industrialized world. We aimed to genomically and phenotypically characterise invasive GBS isolates in Slovenia from 2001 to 2018 and contemporary colonising GBS isolates from screening cultures in 2018. Methods: GBS isolates from 101 patients (invasive isolates) and 70 pregnant women (colonising isolates) were analysed. Basic clinical characteristics of the patients were collected from medical records. Antimicrobial susceptibility and phenotypic capsular serotype were determined. Whole-genome sequencing was performed to assign multilocus sequence types (STs), clonal complexes (CCs), pathogenicity/virulence factors, including capsular genotypes, and genome-based phylogeny. Results: Among invasive neonatal disease patients, 42.6% (n = 43) were females, 41.5% (n = 39/94) were from preterm deliveries (< 37 weeks gestation), and 41.6% (n = 42) had early-onset disease (EOD). All isolates were susceptible to benzylpenicillin with low minimum inhibitory concentrations (MICs; ≤0.125 mg/L). Overall, 7 serotypes were identified (Ia, Ib, II-V and VIII); serotype III being the most prevalent (59.6%). Twenty-eight MLST STs were detected that clustered into 6 CCs. CC-17 was the most common CC overall (53.2%), as well as among invasive (67.3%) and non-invasive (32.9%) isolates (p < 0.001). CC-17 was more common among patients with late-onset disease (LOD) (81.4%) compared to EOD (47.6%) (p < 0.001). The prevalence of other CCs was 12.9% (CC-23), 11.1% (CC-12), 10.5% (CC-1), 8.2% (CC-19), and 1.8% (CC-498). Of all isolates, 2.3% were singletons. Conclusions: A high prevalence of hypervirulent CC-17 isolates, with low genomic diversity and characteristic profile of pathogenicity/virulence factors, was detected among invasive neonatal and colonising GBS isolates from pregnant women in Slovenia. This is the first genomic characterisation of GBS isolates in Slovenia and provides valuable microbiological and genomic baseline data regarding the invasive and colonising GBS population nationally. Continuous genomic surveillance of GBS infections is crucial to analyse the impact of IND prevention strategies on the population structure of GBS locally, nationally, and internationally.
- Open Access
- 28 October 2018
- Published by Slovenian Medical Association in Slovenian Medical Journal
- Vol. 87 (9-10) , 405-416
Hemolitična bolezen novorojenčka
Haemolytic disease of the foetus and newborn (HDFN) occurs when maternal alloimmune antibodies cross the placenta to the foetal circulation and cause destruction of erythrocytes, resulting in anaemia and hyperbilirubinemia. It can result from naturally present antibodies, such as anti-A and anti-B antibodies, or isoantibodies produced by women previously sensitised during pregnancy or transfusion of incompatible erythrocytes such as anti-D antibodies. RhD antigen is the most immunogenic and causes severe HDFN, while the spectrum of HDFN due to AB0 incompatibility ranges from subclinical to severe, requiring exchange transfusion. Thanks to effective and widely implemented prophylaxis with administration of anti-D immunoglobulin to RhD negative women, the HDFN due to anti-D is nowadays a rare disease. Present paper provides an overview on the pathophysiology, clinical characteristics, diagnostics, treatment and prevention of HDFN. In the second part of the article we present the results of a cohort retrospective analysis of 109 patients with HDFN hospitalised at the tertiary neonatal unit during 2007–2016. In 84.4 % of cases the underlying cause of HDFN were antibodies anti-A or anti-B, in 9.2 % of cases antibodies anti-D and in 6.4 % other more rare antibodies. HDFN caused by different antibodies did not result in statistically significant differences in the evaluated hematological tests. Direct Coombs test was positive in all patients with HDFN RhD and in 64 % of newborns with HDFN AB0. All patients with HDFN RhD required exchange transfusion or intrauterine transfusion.
- 28 October 2018
- Published by Slovenian Medical Association in Slovenian Medical Journal
- Vol. 87 (9-10) , 405-416
Open AccessHemolitična bolezen novorojenčka
Haemolytic disease of the foetus and newborn (HDFN) occurs when maternal alloimmune antibodies cross the placenta to the foetal circulation and cause destruction of erythrocytes, resulting in anaemia and hyperbilirubinemia. It can result from naturally present antibodies, such as anti-A and anti-B antibodies, or isoantibodies produced by women previously sensitised during pregnancy or transfusion of incompatible erythrocytes such as anti-D antibodies. RhD antigen is the most immunogenic and causes severe HDFN, while the spectrum of HDFN due to AB0 incompatibility ranges from subclinical to severe, requiring exchange transfusion. Thanks to effective and widely implemented prophylaxis with administration of anti-D immunoglobulin to RhD negative women, the HDFN due to anti-D is nowadays a rare disease. Present paper provides an overview on the pathophysiology, clinical characteristics, diagnostics, treatment and prevention of HDFN. In the second part of the article we present the results of a cohort retrospective analysis of 109 patients with HDFN hospitalised at the tertiary neonatal unit during 2007–2016. In 84.4 % of cases the underlying cause of HDFN were antibodies anti-A or anti-B, in 9.2 % of cases antibodies anti-D and in 6.4 % other more rare antibodies. HDFN caused by different antibodies did not result in statistically significant differences in the evaluated hematological tests. Direct Coombs test was positive in all patients with HDFN RhD and in 64 % of newborns with HDFN AB0. All patients with HDFN RhD required exchange transfusion or intrauterine transfusion.