| 1. |
- Holmbom, Martin, 1984-
(författare)
-
Clinical Impact of Bloodstream Infections – Characterization, Risk factors and Outcome
- 2021
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Bloodstream infection (blood poisoning) and antibiotic resistance are increasing worldwide, and already cause the loss of millions of human lives each year. According to the World Health Organisation (WHO), bloodstream infections (BSIs) represent 20% of global mortality on a par with cardiac infarct, stroke, and major trauma. BSI may occur when bacteria from a focus of infection gain access to the circulation (bacteraemia). BSIs are usually divided into two subclasses: community- and hospital-onset infections, since disease this involves different patient groups, types of bacteria, and reasons for infection. Compared to other countries, Sweden has been fortunate in having a relatively low death rate from BSI and low antibiotic resistance. However, as our lifestyle changes, the age of the population increases with more disease as a result, and as the healthcare system responds, death from infection and antibiotic resistance are on the increase. It is important that we recognise ”warning symptoms” if we are to manage BSIs correctly and initiate effective treatment. It is difficult to design individualised empirical treatment, so it is very important to be aware of risk factors for BSI and local resistance patterns, and to have an effective management programme. Bacterial resistance to antibiotics is an increasing problem, especially in bowel organisms that can cause infections that are very difficult to treat. In short, antibiotic resistance arises as a result of evolutionary processes where bacteria protect themselves by developing resistance genes. These genes can be exchanged between similar organisms or transmitted to others that in turn cause resistant infection. The use of antibiotics leads to an evolutionary/selection process leading to resistance in bacteria, both normal and pathogenic, enabling resistant organisms to survive, thrive, and go on to cause infection. Antibiotic resistance is a threat to global health. This thesis aims to increase our awareness of a large group of patients who suffer bloodstream infection. BSIs are increasing globally, and the death toll is high. Antibiotic resistance is an increasing threat to the health of the population, and we are inundated by alarming reports of resistance getting out of control. What is the situation in Sweden, and can we identify risk factors for BSI and mortality? In Study I, our aim was to study the incidence and mortality of BSI in Östergötland. To be able to do this, a large patient population stretching over several years was required. The study design was thus population-based in the form of an observational cohort study where all blood culture results from 2000 to 2013 were analysed, and evaluated from clinical data. A total of 109,938 results were analysed resulting in 11,480 BSIs. We saw that the incidence of BSI increased by 64% (mostly community-onset BSIs). We also saw that mortality increased by 45%. These results illustrate the importance of nationwide cooperation to combat the increasing problem of BSI and its mortality, and the establishment of a nationwide BSI register. The aim of Study II was to assess resistance development in Östergötland and its relationship to mortality. A total of 9,587 microorganisms were analysed between 2008 and 2016. We observed an increase in quinolone resistance (3.7-7.7%) and cephalosporin resistance (2.5-5.2%) amongst Enterobacteriaceae. We then looked at BSIs caused by multiresistant bacteria showing a total of 245 cases (2.6%); an increase of 300%. Despite this, we did not see an increased mortality in this group. There are several possible explanations for the increase in BSI mortality of which antibiotic resistance is a predominant factor globally. We were unable to show this in our study, even so mortality is increasing and is currently at a high level. In Study III we therefore analysed risk factors associated with death during a community-acquired BSI, focusing on preliminary prehospital and hospital management. In a retrospective case-control study on 195 deaths matched 1:1 regarding age, gender, and microorganism, with 195 survivors (controls). Results showed that many patients had contacted the primary healthcare system because of infection before they became severely ill, and that the strongest affectable risk factor for death was delay (>24h) between primary healthcare visit and admission to hospital. This shows the need for increased awareness in society and amongst the medical profession of those patients at risk and symptoms that should raise the alarm, leading to more rapid treatment. In Studies I and II we found an increase in both BSIs and mortality, we also saw an increase in antibiotic resistance and multiresistant bacteria, mainly ESBL-producing E. coli. On the other hand, we did not see any coupling between multiresistance and mortality in this Swedish population. E. coli is a gram-negative bacteria that causes most BSIs. Since E. coli is predominantly a urine tract pathogen, Study IV aimed to study BSIs caused by ESBL-producing E. coli originating from the urinary tract. We studied the prevalence of E. coli clones, resistance genes and risk factors, as well as any signs of increased mortality from ESBL-producing E. coli compared to sensitive E. coli. Our main finding was a surprisingly low mortality from ESBL-producing E. coli (3%). Most patients in the ESBL-producing E. coli group received inadequate antibiotic treatment for at least 48h, but we did not see any sign of increased mortality or risk for serious sepsis with circulatory failure in this group. This finding is interesting and opens up for new studies on virulence factors and immunological factors that govern the immune response to BSI. The implementation of cost-effective monitoring systems including clinical microbiological epidemiology and early identification of BSI, together with information campaigns aimed at the public as well as healthcare personnel regarding patients at risk and symptoms giving cause for alarm, should lead to a radical reduction in morbidity and mortality from BSI. This requires new diagnostic tools to individualise both antibiotic treatment and targeted management based on microorganism virulence factors. Modernisation of the medical journal system with algorithms aimed at early identification of risk patients and automated suggestions for empirical antibiotic treatment based on antibiotic resistance seen in previous cultures and local resistance patterns, would certainly improve management. Furthermore, new immunological tests showing the type of immunological reaction to a serious BSI will lead to individualised immunotherapy that, together with antibiotic treatment, will further improve patient care in this important group.
|
|
| 2. |
- Aljabery, Firas
(författare)
-
Staging and tumor biological mechanisms of lymph node metastasis in invasive urinary bladder cancer
- 2017
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Aim: To study the possibility of detecting lymph node metastasis in locally advanced urinary bladder cancer (UBC) treated with radical cystectomy (RC) by using preoperative positron emission tomography/computed tomography (PET/CT) and peroperative sentinel node biopsy (SNB) technique. We also investigate the clinical significance of macrophage traits expression by cancer cells, M2-macrophage infiltration (MI) in tumor stroma and the immunohistochemical expression of biomarkers in cancer cells in relation to clinicopathologic data.Patients and Methods: We studied prospectively 122 patients with UBC, pathological stage pT1–pT4 treated with RC and pelvic lymph node dissection (PLND) during 2005–2011 at the Department of Urology, Linköping University Hospital. In the first study, we compared the results of preoperative PET/CT and conventional CT with the findings of postoperative histopathological evaluation of lymph nodes (LNs). In the second study we investigated the value of SNB technique for detecting pathological LNs during RC in patients with UBC. W also examined the significance of the primary tumor location in the bladder in predicting the site of LN metastases, and the prognostic significance of lympho-vascular invasion (LVI) and lymph node metastasis density (LNMD) on survival. In the third study, we investigate the clinical significance of macrophage infiltration (MI) in tumor stroma and macrophage-traits expression by tumor cells. In the fourth study, we investigate the cell cycle suppression proteins p53, p21, pRb, p16, p14 ARF as well as tumors proliferative protein Ki67 and DNA repair protein ERCC1 expression in cancer cells. The results were compared with clinical and pathological characteristics and outcome.Results: Prior to RC, PET/CT was used to detect LN metastasis in 54 patients. PET/CT had 41% sensitivity, 86% specificity, 58% PPV, and 76% NPV, whereas the corresponding figures for conventional CT were 41%, 89%, 64%, and 77%. SNB was performed during RC in 103 patients. A median number of 29 (range 7–68) nodes per patient were examined. SNs were detected in 83 out of 103 patients (81%). The sensitivity and specificity for detecting metastatic disease by SNB varied among LN stations, with average values of 67% -90%. LNMD or ≥8% and LVI were significantly related to shorter survival. In 103 patients, MI was high in 33% of cases, while moderate and low infiltration occurred in 42% and 25% of tumors respectively. Patients with tumors containing high and moderate compared to low MI had low rate of LN metastases (P=0.06) and improved survival (P=0.06), although not at significant level. The expression of different tumor suppression proteins was altered in 47-91% of the patients. There were no significant association between cancer specific survival (CSS) and any of the studied biomarkers. In case of altered p14ARF, ERCC1 or p21, CSS was low in case of low p53 immunostaining but increased in case of p53 accumulation, although not at a significant level, indicating a possible protective effect of p53 accumulation in these cases.Conclusion: PET/ CT provided no improvement over conventional CT in detection and localization of regional LN metastases in bladder cancer. It is possible to detect the SN but the technique is not a reliable for perioperative localization of LN metastases; however, LVI and LNMD at a cut-off level of 8% had significant prognostic values. MI in the tumor microenvironment but not CD163 expression in tumor cells seems to be synergistic with the immune response against urinary bladder cancer. Our results further indicate that altered p53 might have protective effect on survival in case of altered p14ARF, p21, or ERCC1 indicating an interaction between these biomarkers.
|
|
| 3. |
- Andersson-Evelönn, Emma, 1983-
(författare)
-
DNA methylation as a prognostic marker in clear cell Renal Cell Carcinoma
- 2020
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Clear cell renal cell carcinoma (ccRCC) is the most common type of renal cell carcinoma worldwide. Metastatic ccRCC is correlated to poor prognosis whereas non-metastatic disease has a 5-year survival rate up to 90%. Due to increased accessibility to different types of diagnostic imaging the frequency of metastatic ccRCC at diagnosis has decreased since the beginning of the 21st century. This has led to an earlier detection of primary tumors before patients present symptoms. However, 20-30% of the non-metastatic patients at diagnosis will progress and metastasize within five years of primary nephrectomy. Identifying patients at high risk of tumor progression at an early stage after diagnosis is of importance to improve outcome and survival. Currently, in Sweden, the Mayo scoring system is used to divide tumors into low, intermediate or high risk for tumor progression.DNA methylation has been associated with tumor development and progression in different malignancies. In this thesis, Illumina Infinium HumanMeth27 BeadChip Arrays and Human Meth450K BeadChip Arrays have been used to evaluate the relationship between methylation and clinicopathological variables as well as ccRCC outcome in 45 and 115 patients.Our studies identified an association between higher level of promoter-associated DNA methylation and clinicopathological variables in ccRCC. There was a significant stepwise increase of average methylation from tumor-free tissue, via non-metastatic tumors to metastatic disease. Cluster analysis divided patients into two distinct groups that differed in average methylation levels, TNM stage, Fuhrman nuclear grade, tumor size, survival and tumor progression. We also presented two prognostic classifiers for non-metastatic tumors; the promoter methylation classifier (PMC) panel and the triple classifier. The PMC panel divided tumors depending on the methylation level, PMC low or PMC high, with significantly worse prognosis in the PMC high group. This data was verified in an independent, publically available cohort. The triple classifier was created using a combination of clinicopathological variables, previously identified CpGs biomarkers and a novel cluster analysis approach (Directed Cluster Analysis). The triple classifier had a higher specificity compared to the clinically used Mayo scoring system and predicted tumor progression with higher accuracy at a fixed sensitivity.The identification of two epigenetic classifiers that predicted outcome in non-metastatic ccRCC further establishes the role of DNA methylation as a prognostic marker. This knowledge can contribute to identification of patients with a high risk of tumor progression and can be of importance in the decision regarding adjuvant treatment post-nephrectomy.
|
|
| 4. |
- Rosenblatt, Robert, 1982-
(författare)
-
Neoadjuvant chemotherapy in muscle-invasive urinary bladder cancer : studies on treatment response, tumor draining lymph nodes and blood transfusion
- 2020
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Muscle-invasive urinary bladder cancer is a deadly disease. Mortality rates remained unchanged for decades despite radical surgery.After several randomized trials, we today know that cisplatin based chemotherapy given prior to cystectomy, improves survival for every tenth patient. Markers that predict responsiveness to chemotherapy would spare unnecessary treatment to the majority of patients. In the search for signs of chemosensitivity, we performed a retrospective analysis of the Nordic cystectomy trials 1 & 2: Chemo treated patients had an almost doubled increase in tumor downstaging compared to the controls. More importantly, this group presented with a reduced absolute risk of death of more than 30% compared to the rest of the patients. These results were presented in paper I.Many cancers spread through the lymphatic system. Usually, there is at least one tumor draining lymph node, referred to as the sentinel node. If this node is free of metastases, there is no lymphatic spread of the disease, and consequently, no use of excavating all neighboring lymph nodes.Sentinel node detection, is an established method in breast cancer, penile cancer and malignant melanoma. Based on the same principles, members of our group developed a similar detection technique in bladder cancer. Unfortunately, sensitivity and specificity were too low to rely on this method as a diagnostic tool for lymphatic spread. Instead, it turned out in recent years that sentinel nodes in muscle invasive bladder cancer are valuable for translational research-lines - mainly in tumor immunology. As for example, sentinel nodes contain tumor specific T cells that are useful in adoptive immunotherapy.In paper II, we set out to test whether sentinel node detection was feasible after chemotherapy and/or tumor downstaging. In a prospective cohort of patients, we saw no difference in detection rates between the groups. Thus, we concluded, neither chemotherapy nor downstaging appeared to hamper the identification of sentinel nodes.The concept was expanded in paper III. After recruiting more patients to the cohort mentioned above, the average numbers of sentinel nodes in different categories of patients were compared. We saw a pattern of decreased number of sentinel nodes in those with locally advanced tumors. It seemed that the number of sentinel nodes had prognostic implications.In the last study, published in paper IV, we wanted to widen our knowledge on the clinical effects of blood transfusion. Mounting data suggests that perioperative blood products have a negative impact on long term survival after cancer surgery. How much allogenic blood was given during the chemotherapy prior to surgery ? It turned out that one third of the bladder cancer patients received blood, and these patients demonstrated a significantly worse overall survival.Neoadjuvant chemotherapy has added a new beneficial dimension to the treatment of muscle invasive bladder cancer. In these four studies, we addressed the effects of chemotherapy on pathoanatomical outcomes, on tumor lymphatics and further; we are suggesting consequences of neoadjuvant chemotherapy in conjunction with blood transfusion. It appears that the immune system is involved in all aspects investigated above. Most likely, an improved scientific understanding of the immune system will be crucial for future bladder cancer treatment options.
|
|
| 5. |
- Åkerlund, John, et al.
(författare)
-
End-stage renal disease after renal cancer surgery : risk factors and overall survival
- 2024
-
Ingår i: Scandinavian journal of urology. - : Medical Journals Sweden. - 2168-1805 .- 2168-1813. ; 59, s. 109-116
-
Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: Several risk factors for end-stage renal disease (ESRD), in patients undergoing surgical treatment for renal cell carcinoma (RCC), have been suggested by others. This study aimed to investigate such risk factors and disclose the effect of developing ESRD, postoperatively, on overall survival. The risk of developing ESRD after RCC diagnosis was also evaluated.MATERIAL AND METHODS: The data of 16,220 patients with RCC and 162,199 controls were extracted from the Renal Cell Cancer Database Sweden, with linkages across multiple national registers between 2005 and 2020. Cox proportional hazards regression, Kaplan-Meier curves and cumulative incidence were used for statistical analysis.RESULTS: The 5-year cumulative incidence of ESRD following RCC diagnosis was 2.4% (95% confidence interval [CI] 2.1-2.6) and 0.4% (95% CI 0.3-0.4) for the patients with RCC and controls, respectively. Age, chronic kidney disease, higher T-stage and radical nephrectomy (RN) were significant risk factors for ESRD within 1-year of surgery. A total of 104 and 12,152 patients with and without ESRD, respectively, survived 1-year postoperatively. The 5-year overall survival rates of patients with ESRD and those with RCC only were 50% (95% CI 0.40-0.60) and 80% (95% CI 0.80-0.81), respectively.CONCLUSIONS: Patients who developed ESRD following renal cancer surgery had significantly poorer survival outcomes. Advanced age, comorbidities, higher-stage tumours and RN were identified as risk factors for developing ESRD. Surgical decisions are crucial. Efforts to spare renal function, including nephron-sparing surgery and active surveillance in appropriate cases, are highly relevant to reduce the development of severe kidney dysfunction.
|
|
| 6. |
- Åkerlund, John, et al.
(författare)
-
Predictors for complication in renal cancer surgery : a national register study
- 2023
-
Ingår i: Scandinavian journal of urology. - : Taylor & Francis. - 2168-1805 .- 2168-1813. ; 58:1, s. 38-45
-
Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: Nationwide register data provide unique opportunities for real-world assessment of complications from different surgical methods. This study aimed to assess incidence of, and predictors for, post-operative complications and to evaluate 90-day mortality following different surgical procedures and thermal ablation for renal cell carcinoma (RCC).MATERIAL AND METHODS: All patients undergoing surgical treatment and thermal ablation for RCC in Sweden during 2015-2019 were identified from the National Swedish Kidney Cancer Register. Frequencies and types of post-operative complications were analysed. Logistic regression models were used to identify predictors for 90-day major (Clavien-Dindo grades III-V) complications, including death.RESULTS: The overall complication rate was 24% (1295/5505), of which 495 (8.7%) were major complications. Most complications occurred following open surgery, of which bleeding and infection were the most common. Twice as many complications were observed in patients undergoing open surgery compared to minimally invasive surgery (20% vs. 10%, P < 0.001). Statistically significant predictors for major complications irrespective of surgical category and technique were American society of anesthiologists (ASA) score, tumour diameter and serum creatinine. Separating radical and partial nephrectomy, surgical technique remained a significant risk factor for major complications. Most complications occurred within the first 20 days. The overall 90-day readmission rate was 6.2%, and 30- and 90-day mortality rates were 0.47% and 1.5%, respectively.CONCLUSIONS: In conclusion, bleeding and infection were the most common major complications after RCC surgery. Twice as many patients undergoing open surgery suffer a major post-operative complication as compared to patients subjected to minimally invasive surgery. General predictors for major complications were ASA score, tumour size, kidney function and surgical technique.
|
|
