Erik Sörstedt

Dr. Erik Sörstedt


Research Focus & Metrics

Academic Career Length

11Years (2016-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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21 June 2016 in BMC Infectious Diseases
Verified
Journal Article
Open access
PDF file
ESErik Sörstedt
Erik Sörstedt
SNStaffan Nilsson
Staffan Nilsson
ABAnders Blaxhult
Anders Blaxhult
MGMagnus Gisslén
Magnus Gisslén
LFLeo Flamholc
Leo Flamholc
AYAylin Yilmaz
Aylin Yilmaz
Many HIV-1-infected patients on suppressive antiretroviral therapy (ART) have transiently elevated HIV RNA levels. The clinical significance of these viral blips is uncertain. We have determined the incidence of blips and investigated important associations in the Swedish HIV-cohort. HIV-1-infected ART naïve adults who commenced ART 2007–2013 were retrospectively included. Viral blips were defined as a transient viral load between 50 and 500 copies/mL Subjects not suppressed after six months on ART were excluded. Viral blips were found in 76/735 included subjects (10.3 %) and in 90/4449 samples (2.0 %). Median blip viral load was 76 copies/mL (range 56–138). Median follow-up time was 170 weeks (range 97–240). Baseline viral load was higher in subjects with viral blips (median log10 4.85 copies/mL) compared with subjects without blips (median log10 4.55 copies/mL) (p < 0.01). There was a significant association between viral blips and risk for subsequent virological failure (p < 0.001). The Swedish national HIV-cohort has a low incidence of viral blips (10 %). Blips were associated with high baseline viral load and an increased risk of subsequent virological failure.

1 May 2018 in International Journal of Antimicrobial Agents
Verified
Journal Article
Closed access
ESErik Sörstedt
Erik Sörstedt
CCChristina Carlander
Christina Carlander
LFLeo Flamholc
Leo Flamholc
BHBo Hejdeman
Bo Hejdeman
VSVeronica Svedhem
Veronica Svedhem
AYAylin Yilmaz
Aylin Yilmaz

24 September 2024 in Microorganisms
Verified
Journal Article
Open access
PDF file
ESErik Sörstedt
Erik Sörstedt
GAGustaf Ahlbeck
Gustaf Ahlbeck
USUlrika Snygg-Martin
Ulrika Snygg-Martin
Enterococcal bacteremia (EB) is on the rise both in Sweden and globally. While Enterococcus faecalis (E. faecalis) is susceptible to ampicillin and piperacillin/tazobactam (pip/taz), Enterococcus faecium (E. faecium) is not. Historically, most enterococcal infections have been caused by E. faecalis, but the epidemiology is changing with increasing recognition of enterococci as nosocomial pathogens and the emergence of resistance to commonly used antimicrobial agents. The use of pip/taz has increased dramatically in Sweden, but it is unknown if this has affected the relative incidence of E. faecalis/E. faecium bacteremia. Here, we investigate whether the number and proportion of E. faecium bacteremia (EfmB) cases have increased. Additionally, risk factors associated with EfmB with a focus on prior antibiotic exposure are analyzed. Medical journals of 360 patients with EB admitted to Sahlgrenska University Hospital are reviewed. The proportion of EfmB cases increased from 41% in 2015 to 51% in 2021. Hospital-acquired infection, previous exposure to pip/taz, and carbapenems are identified as independent risk factors for EfmB. There are considerable patient-related differences between the EfmB and EfsB groups, but there is no difference in mortality rates. In conclusion, the increasing proportion of EfmB cases is concerning and is seen parallel to the expanding use of pip/taz, one possible contributing factor. Our findings suggest that a cautious approach to antibiotic use is essential to prevent the spread of antibiotic-resistant bacteria.

12 November 2024 in The Journal of Infectious Diseases
Verified
Journal Article
Open access
GUGustaf Ulfhammer
Gustaf Ulfhammer
AYAylin Yilmaz
Aylin Yilmaz
ÅMÅsa Mellgren
Åsa Mellgren
ETErika Tyrberg
Erika Tyrberg
ESErik Sörstedt
Erik Sörstedt
MGMagnus Gisslén
Magnus Gisslén
Background: The incidence and clinical relevance of asymptomatic cerebrospinal fluid escape (CSFE) during antiretroviral therapy (ART) is uncertain. We examined the impact and incidence of asymptomatic CSFE in a Swedish HIV cohort. Methods: Neuroasymptomatic people with HIV (PWH) who have been on ART for at least 6 months with suppressed plasma viral load were followed longitudinally. CSFE was defined as either increased CSF HIV-1 RNA with concurrent plasma suppression or CSF HIV-1 RNA exceeding that in plasma when both were quantifiable. Paired CSF and plasma were analyzed for HIV-1 RNA, neopterin, neurofilament light protein (NfL), white blood cell (WBC) count, and albumin ratio. Results: Asymptomatic CSFE (cutoff 50 copies/mL) was found in 4 of 173 PWH (2%) and 5 of 449 samples (1%). The corresponding proportions were 8% of PWH and 4% for samples using a 20 copies/mL cutoff for CSF HIV-1 RNA. CSFE samples (cutoff 20 copies/mL) had a 25% higher geometric mean of CSF neopterin (P = .01) and 8% higher albumin ratio (P = .04) compared to samples without CSFE. No differences were observed in CSF NfL levels (P = .8). The odds ratio for increased CSF WBC (≥ 3 cells/μL) in samples with CSFE was 3.9 (P = .004), compared to samples without elevated CSF viral load. Conclusions: Asymptomatic CSFE was identified in only 4 (2%) PWH, with no cases of continuous CSFE observed. Increased CSF HIV-1 RNA was associated with biomarkers of CNS immune activation and blood-brain barrier impairment, but not with biomarkers of neuronal injury.

10 November 2022 in AIDS
Verified
Journal Article
Closed access
ESErik Sörstedt
Erik Sörstedt
MTMalte Mose Tetens
Malte Mose Tetens
SNStaffan Nilsson
Staffan Nilsson
PNPiotr Nowak
Piotr Nowak
CTCarl Johan Treutiger
Carl Johan Treutiger
AYAylin Yilmaz
Aylin Yilmaz
Background: The impact of pre-antiretroviral treatment (ART) HIV-RNA on time to successful virological suppression and subsequent failure in HIV patients remains poorly investigated. Methods: We used the Swedish InfCareHIV database and the Danish HIV Cohort Study to evaluate impact of pre-ART HIV-RNA on primary virological suppression (HIV-RNA < 50 copies/ml) and risk of secondary virological failure (two consecutive HIV-RNA > 200 copies/ml or one >1000 copies/ml). The study included 3366 Swedish and 2050 Danish ART naïve individuals who initiated ART in the period 2000–2018. We used Kaplan–Meier estimates and Cox regression analyses to estimate absolute risks and hazard ratios. Results: In both cohorts, more than 95% of patients with a pre-ART HIV-RNA 1 000 000 copies/ml. Almost all patients obtained virological suppression after four years irrespective of pre-ART HIV-RNA. In contrast, we observed no substantial impact of pre-ART HIV-RNA on risk of virological failure once virological suppression was obtained. Conclusion: High pre-ART HIV-RNA is strongly associated with increased time to successful virological suppression, but pre-ART HIV-RNA has no impact on risk of subsequent virological failure.

9 July 2024 in Preprints.org
Verified
Preprint
Open access
PDF file
ESErik Sörstedt
Erik Sörstedt
GAGustaf Ahlbeck
Gustaf Ahlbeck
USUlrika Snygg-Martin
Ulrika Snygg-Martin
Enterococcal bacteraemia (EB) is on the rise both in Sweden and globally. While Enterococcus faecalis (E. faecalis) is susceptible to ampicillin and piperacillin/tazobactam (pip/taz), Enterococcus faecium (E. faecium) is not. The use of pip/taz has increased dramatically in Sweden, but it is unknown if this has affected the relative incidence of E. faecalis/E. faecium bacteraemia. Here we investigate whether the number and proportion of E. faecium bacteraemia (EfmB) cases have increased. Additionalle, risk factors associated with EfmB with focus on prior antibiotic exposure are analyzed. Medical journals of 360 patients with EB admitted to Sahlgrenska University Hospital were reviewed. The proportion of EfmB cases increased from 41% in 2015 to 51% in 2021. Hospital-acquired infection, previous exposure to pip/taz, and carbapenems were identified as independent risk factors for EfmB. There were considerable patient related differences between the EfmB and EfsB groups but there was no difference in mortality rates. In conclusion, the increasing proportion of EfmB cases is concerning and was seen parallell to the expanding use of pip/taz, one possible contributing factor. Our findings suggest that a cautious approach to antibiotic use is essential to prevent the spread of antibiotic-resistant bacteria.