Outbreak of Listeria monocytogenes in hospital linked to a fava bean product, Finland, 2015 to 2019.

Listeria monocytogenes (Lm) is a bacterium widely distributed in the environment. Listeriosis is a severe disease associated with high hospitalisation and mortality rates. In April 2019, listeriosis was diagnosed in two hospital patients in Finland. We conducted a descriptive study to identify the source of the infection and defined a case as a person with a laboratory-confirmed Lm serogroup IIa sequence type (ST) 37. Six cases with Lm ST 37 were notified to the Finnish Infectious Diseases Registry between 2015 and 2019. Patient interviews and hospital menus were used to target traceback investigation of the implicated foods. In 2021 and 2022, similar Lm ST 37 was detected from samples of a ready-to-eat plant-based food product including fava beans. Inspections by the manufacturer and the local food control authority indicated that the food products were contaminated with Lm after pasteurisation. Our investigation highlights the importance that companies producing plant-based food are subject to similar controls as those producing food of animal origin. Hospital menus can be a useful source of information that is not dependent on patient recall.

Staphylococcus aureus bacteremia in alcoholics.

BACKGROUND: Alcoholism associates with increased Staphylococcus aureus bacteremia incidence and mortality. The objective was to compare disease progression, treatment and prognosis of Staphylococcus aureus bacteremia in alcoholics versus non-alcoholics. METHODS: The study design was a multicenter retrospective analysis of methicillin-sensitive Staphylococcus aureus bacteremia with 90-day follow-up. Patients were stratified as alcoholics or non-alcoholics based on electronic health record data. Altogether 617 Staphylococcus aureus bacteremia patients were included of which 83 (13%) were alcoholics. RESULTS: Alcoholics, versus non-alcoholics, were younger, typically male and more commonly had community-acquired Staphylococcus aureus bacteremia. No differences in McCabe´s classification of underlying conditions was observed. Higher illness severity at blood culture sampling, including severe sepsis (25% vs. 7%) and intensive care unit admission (39% vs. 17%), was seen in alcoholics versus non-alcoholics. Clinical management, including infectious disease specialist (IDS) consultations and radiology, were provided equally. Alcoholics, versus non-alcoholics, had more pneumonia (49% vs. 35%) and fewer cases of endocarditis (7% vs. 16%). Mortality in alcoholics versus non-alcoholics was significantly higher at 14, 28 and 90 days (14% vs. 7%, 24% vs. 11% and 31% vs. 17%), respectively. Considering all prognostic parameters, male sex (OR 0.19, p = 0.021) and formal IDS consultation (OR 0.19, p = 0.029) were independent predictors of reduced mortality, whereas ultimately or rapidly fatal comorbidity in McCabe´s classification (OR 12.34, p < 0.001) was an independent predictor of mortality in alcoholics. CONCLUSIONS: Alcoholism deteriorates Staphylococcus aureus bacteremia prognosis, and our results suggests that this is predominantly through illness severity at bacteremia onset. Three quarters of Staphylococcus aureus bacteremia patients we studied had identified deep infection foci, and of them alcoholics had significantly less endocarditis but nearly half of them had pneumonia.

Molecular characteristics of Cryptosporidium spp. in human cases in five Finnish hospital districts during 2021: first findings of Cryptosporidium mortiferum (Cryptosporidium chipmunk genotype I) in Finland.

The aims of the study were to characterise the distribution of Cryptosporidium spp. and subtypes causing infections in Finland during 2021. This was carried out with 60 clinical samples from the hospital districts of Helsinki and Uusimaa, Vaasa, Kymenlaakso, South Karelia, and Central Finland, as well as with Finnish Infectious Diseases Register (FIDR) data. Additionally, the study aimed to explore the potential exposures related to Cryptosporidium mortiferum (Cryptosporidium chipmunk genotype I) infections via interview. Species identification was carried out with quantitative real-time PCR (qPCR) and 18S sequencing. Further typing was performed with gp60 subtyping. Over 70% of the samples were identified as Cryptosporidium parvum and 20% as C. mortiferum, which had not been identified in Finland before. Two cases of Cryptosporidium hominis were identified from patients reported to have travelled outside Europe. The C. parvum subtype IIaA15G2R1 and the C. mortiferum subtype XIVaA20G2T1 were the most common subtypes identified. The interviewed C. mortiferum cases did not report shared exposures such as contact with wild rodents. In conclusion, C. parvum and C. mortiferum were the major causes of cryptosporidiosis in the five studied Finnish hospital districts.

Severe acute otitis media and mastoiditis caused by group A beta-hemolytic streptococcus.

OBJECTIVE: To describe the characteristics, diagnostics, treatment, and outcome of severe acute otitis media (AOM) and acute mastoiditis (AM) caused by group A beta-hemolytic streptococcus (GAS). STUDY DESIGN: A retrospective cohort study. METHODS: The yearly incidence of inpatient care-needing GAS AOM/AM patients in our hospital catchment area between 2002 and 2018 was investigated. A detailed analysis was performed for cases treated during the last GAS epidemic in 2017-2018. Anamnesis, signs and symptoms, pure-tone audiometry results, treatment, complications, and outcome were collected from medical charts. Patients responded to an otology-specific health-related quality of life survey (EOS-16) 1.5 to 3 years after their treatment. RESULTS: The number of GAS infections peaks at approximately 7-year intervals. During 2017 and 2018, altogether 37 patients (29 adults and 8 children) were hospitalized due to GAS AOM/AM. AM was diagnosed in 14 (38%) patients. The disease progression was typically very rapid. At presentation, all patients had severe ear pain, 68% tympanic membrane perforation and discharge, 43% fever, and 43% vertigo. In pure-tone audiometry, there was usually a marked mixed hearing loss at presentation. There was a significant recovery in both air and bone conduction thresholds; the pure tone average improvement from presentation was 32.3 ± 14.8 dB. Rapid strep tests (RST) proved to be more sensitive than bacterial culture in identifying GAS as a cause of AOM/AM. CONCLUSION: GAS AOM/AM has a rapid onset. Hearing loss usually includes a sensorineural component, which is usually reversible with adequate treatment. RST seems to be useful in detecting GAS from middle ear discharge. LEVEL OF EVIDENCE: 4.

Matrix metalloproteinase MMP-8, TIMP-1 and MMP-8/TIMP-1 ratio in plasma in methicillin-sensitive Staphylococcus aureus bacteremia.

BACKGROUND: Matrix metalloproteinase-8 (MMP-8) and tissue inhibitor of metalloproteinases-1 (TIMP-1) have been shown to predict prognosis in sepsis. However, MMP-8 and TIMP-1 in Staphylococcus aureus bacteremia (SAB) lacks evaluation and their role in the pathogenesis of SAB is unclear. METHODS: MMP-8 and TIMP-1 and MMP-8/TIMP-1 molar ratio were determined at days 3, 5 and 28 from positive blood cultures in patients with methicillin-sensitive SAB and the connection to disease severity and early mortality was determined. RESULTS: Altogether 395 SAB patients were included. Patients with severe sepsis or infection focus presented higher MMP-8 levels at day 3 and 5 (p<0.01). Higher day 3 and 5 MMP-8 levels were associated to mortality at day 14 and 28 (p<0.01) and day 90 (p<0.05). Day 3 MMP-8 cut-off value of 203 ng/ml predicted death within 14 days with an area under the curve (AUC) of 0.70 (95% CI 0.57-0.82) (p<0.01). Day 5 MMP-8 cut-off value of 239 ng/ml predicted death within 14 days with an AUC of 0.76 (95% CI 0.65-0.87) (p<0.001). The results for MMP-8/TIMP-1 resembled that of MMP-8. TIMP-1 had no prognostic impact. In Cox regression analysis day 3 or 5 MMP-8 or day 3 MMP-8/TIMP-1 had no prognostic impact whereas day 5 MMP-8/TIMP-1 predicted mortality within 14 days (HR, 4.71; CI, 95% 1.67-13.3; p<0.01). CONCLUSION: MMP-8 and MMP-8/TIMP-1 ratio were high 3-5 days after MS-SAB diagnosis in patients with an infection focus, severe sepsis or mortality within 14 days suggesting that matrix metalloproteinase activation might play a role in severe SAB.

Real-life clinical sensitivity of SARS-CoV-2 RT-PCR test in symptomatic patients.

BACKGROUND: Understanding the false negative rates of SARS-CoV-2 RT-PCR testing is pivotal for the management of the COVID-19 pandemic and it has implications for patient management. Our aim was to determine the real-life clinical sensitivity of SARS-CoV-2 RT-PCR. METHODS: This population-based retrospective study was conducted in March-April 2020 in the Helsinki Capital Region, Finland. Adults who were clinically suspected of SARS-CoV-2 infection and underwent SARS-CoV-2 RT-PCR testing, with sufficient data in their medical records for grading of clinical suspicion were eligible. In addition to examining the first RT-PCR test of repeat-tested individuals, we also used high clinical suspicion for COVID-19 as the reference standard for calculating the sensitivity of SARS-CoV-2 RT-PCR. RESULTS: All 1,194 inpatients (mean [SD] age, 63.2 [18.3] years; 45.2% women) admitted to COVID-19 cohort wards during the study period were included. The outpatient cohort of 1,814 individuals (mean [SD] age, 45.4 [17.2] years; 69.1% women) was sampled from epidemiological line lists by systematic quasi-random sampling. The sensitivity (95% CI) for laboratory confirmed cases (repeat-tested patients) was 85.7% (81.5-89.1%) inpatients; 95.5% (92.2-97.5%) outpatients, 89.9% (88.2-92.1%) all. When also patients that were graded as high suspicion but never tested positive were included in the denominator, the sensitivity (95% CI) was: 67.5% (62.9-71.9%) inpatients; 34.9% (31.4-38.5%) outpatients; 47.3% (44.4-50.3%) all. CONCLUSIONS: The clinical sensitivity of SARS-CoV-2 RT-PCR testing was only moderate at best. The relatively high false negative rates of SARS-CoV-2 RT-PCR testing need to be accounted for in clinical decision making, epidemiological interpretations, and when using RT-PCR as a reference for other tests.

Tuberculosis contact investigation results among paediatric contacts in low-incidence settings in Finland.

Tuberculosis (TB) risk is highest immediately after primary infection, and young children are vulnerable to rapid and severe TB disease. Contact tracing should identify infected children rapidly and simultaneously target resources effectively. We conducted a retrospective review of the paediatric TB contact tracing results in the Hospital District of Helsinki and Uusimaa from 2012 to 2016 and identified risk factors for TB disease or infection. Altogether, 121 index cases had 526 paediatric contacts of whom 34 were diagnosed with TB disease or infection. The maximum delay until first contact investigation visit among the household contacts under 5 years of age with either TB disease or infection was 7 days. The yield for TB disease or infection was 4.6% and 12.8% for household contacts, 0.5% and 0% for contacts exposed in a congregate setting and 1.4% and 5.0% for other contacts, respectively. Contacts born in a TB endemic country (aOR 3.07, 95% CI 1.10-8.57), with household exposure (aOR 2.96, 95% CI 1.33-6.58) or a sputum smear positive index case (aOR 3.96, 95% CI 1.20-13.03) were more likely to have TB disease or infection.Conclusions: Prompt TB investigations and early diagnosis can be achieved with a well-organised contact tracing structure. The risk for TB infection or disease was higher among contacts with household exposure, a sputum smear positive index case or born in a TB endemic country. Large-scale investigations among children exposed in congregate settings can result in a very low yield and should be cautiously targeted. What is Known: • Vulnerable young children are a high priority in contact tracing and should be evaluated as soon as possible after TB exposure What is New: • Prompt investigations for paediatric TB contacts and early diagnosis of infected children can be achieved with a well-organised contact tracing structure • Large-scale investigations among children exposed in congregate settings can result in a very low yield and should be cautiously targeted.

Changes in hemostasis parameters in nonfatal methicillin-sensitive Staphylococcus aureus bacteremia complicated by endocarditis or thromboembolic events: a prospective gender-age adjusted cohort study.

The aim of this study was to examine the changes in hemostasis parameters in endocarditis and thromboembolic events in nonfatal methicillin-sensitive Staphylococcus aureus bacteremia (MS-SAB) - a topic not evaluated previously. In total, 155 patients were recruited and were categorized according to the presence of endocarditis or thromboembolic events with gender-age adjusted controls. Patients who deceased within 90 days or patients not chosen as controls were excluded. SAB management was supervised by an infectious disease specialist. Patients with endocarditis (N = 21), compared to controls (N = 21), presented lower antithrombin III at day 4 (p < 0.05), elevated antithrombin III at day 90 (p < 0.01), prolonged activated partial thromboplastin time at days 4 and 10 (p < 0.05), and enhanced thrombin-antithrombin complex at day 4 (p < 0.01). Thromboembolic events (N = 8), compared to controls (N = 34), significantly increased thrombin-antithrombin complex at day 4 (p < 0.05). In receiver operating characteristic analysis, the changes in these hemostasis parameters at day 4 predicted endocarditis and thromboembolic events (p < 0.05). No differences in hemoglobin, thrombocyte, prothrombin fragment, thrombin time, factor VIII, D-dimer or fibrinogen levels were observed between cases and controls. The results suggest that nonfatal MS-SAB patients present marginal hemostasis parameter changes that, however, may have predictability for endocarditis or thromboembolic events. Larger studies are needed to further assess the connection of hemostasis to complications in SAB.

Seasonal influenza vaccines induced high levels of neutralizing cross-reactive antibody responses against different genetic group influenza A(H1N1)pdm09 viruses.

Influenza A(H1N1)pdm09 viruses have been circulating throughout the world since the 2009 pandemic. A/California/07/2009 (H1N1) virus was included in seasonal influenza vaccines for seven years altogether, providing a great opportunity to analyse vaccine-induced immunity in relation to the postpandemic evolution of the A(H1N1)pdm09 virus. Serum antibodies against various epidemic strains of influenza A(H1N1)pdm09 viruses were measured among health care workers (HCWs) by haemagglutination inhibition and microneutralization tests before and after 2010 and 2012 seasonal influenza vaccinations. We detected high responses of vaccine-induced neutralizing antibodies to six distinct genetic groups. Our results indicate antigenic similarity between vaccine and circulating A(H1N1)pdm09 strains, and substantial vaccine-induced immunity against circulating epidemic viruses.

Formal Infectious Diseases Specialist Consultation Improves Long-term Outcome of Methicillin-Sensitive Staphylococcus aureus Bacteremia.

BACKGROUND: Formal infectious diseases specialist (IDS) consultation has been shown to improve short-term outcomes in Staphylococcus aureus bacteremia (SAB), but its effect on long-term outcomes lacks evaluation. METHODS: This retrospective study followed 367 methicillin-sensitive (MS) SAB patients for 10 years. The impact of formal IDS consultation on risk for new bacteremia and outcome during long-term follow-up was evaluated. Patients who died within 90 days were excluded to avoid interference from early deceased patients. RESULTS: Three hundred four (83%) patients had formal IDS consultation, whereas 63 (17%) received informal or no IDS consultation. Formal consultation, compared with informal or lack of consultation, was associated with a reduced risk of new bacteremia caused by any pathogen within 1 year (odds ratio [OR], 0.39; 95% confidence interval [CI], 0.18-0.84; P = .014; 8% vs 17%) and within 3 years (OR, 0.39; 95% CI, 0.19-0.80; P = .010; 9% vs 21%), whereas a trend toward lower risk was observed within 10 years (OR, 0.56; 95% CI, 0.29-1.08; P = .079; 16% vs 25%). Formal consultation, compared with informal or lack of consultation, improved outcomes at 1 year (OR, 0.16; 95% CI, 0.06-0.44; P < .001; 3% vs 14%), at 3 years (OR, 0.19; 95% CI, 0.09-0.42; P < .001; 5% vs 22%), and at 10 years (OR, 0.43; 95% CI, 0.24-0.74; P = .002; 27% vs 46%). Considering all prognostic parameters, formal consultation improved outcomes (HR, 0.42; 95% CI, 0.27-0.65; P < .001) and lowered risk for any new bacteremia (OR, 0.45; 95% CI, 0.23-0.88; P = .02) during 10 years of follow-up. CONCLUSIONS: MS-SAB management by formal IDS consultation, compared with informal or lack of IDS consultation, reduces risk for new bacteremia episodes and improves long-term prognosis up to 10 years.

Outbreak of multiple strains of non-O157 Shiga toxin-producing and enteropathogenic Escherichia coli associated with rocket salad, Finland, autumn 2016.

In August 2016, an outbreak of Shiga toxin-producing Escherichia coli (STEC) and enteropathogenic E. coli (EPEC) with 237 cases occurred in the Helsinki metropolitan area, Finland. Gastroenteritis cases were reported at 11 events served by one catering company. Microbiological and epidemiological investigations suggested rocket salad as the cause of the outbreak. STEC ONT: H11 and EPEC O111:H8 strains isolated from food samples containing rocket were identical to the patient isolates. In this outbreak, the reported symptoms were milder than considered before for STEC infection, and the guidelines for STEC control measures need to be updated based on the severity of the illness. Based on our experience in this outbreak, national surveillance criteria for STEC have been updated to meet the practice in reporting laboratories covering both PCR-positive and culture-confirmed findings. We suggest that EPEC could be added to the national surveillance since diagnostics for EPEC are routinely done in clinical laboratories.

Comparable Effectiveness of First Week Treatment with Anti-Staphylococcal Penicillin versus Cephalosporin in Methicillin-Sensitive Staphylococcus aureus Bacteremia: A Propensity-Score Adjusted Retrospective Study.

The objective was to compare the prognostic impact of first week treatment with anti-staphylococcal penicillin (ASP) versus cephalosporin in methicillin-sensitive Staphylococcus aureus bacteremia (MS-SAB). Altogether 580 patients were retrospectively followed and categorized according to first week treatment; 84% (488) received ASP (cloxacillin) and 16% (92) cephalosporin (cefuroxime or ceftriaxone). SAB management was optimized with formal bedside infectious disease specialist consultation in 88%, deep infection foci diagnosed in 77% and adjunctive rifampicin therapy given to 61% of patients. The total case fatality in 580 patients was 12% at 28 days and 18% at 90 days. When comparing effectiveness of first week ASP versus cephalosporin treatment there were no significant differences in 28-days (11% vs. 12%, OR; 1.05, 95% CI, 0.53-2.09) or 90-days (17% vs. 21% OR; 1.25, 95% CI, 0.72-2.19) outcome. In univariate analysis no prognostic impact of either first week ASP or cephalosporin treatment was observed for 28-days (OR; 0.96, 95% CI, 0.48-1.90 and OR; 1.05, 95% CI, 0.53-2.09) or 90-days (OR; 0.80, 95% CI, 0.46-1.39 and OR; 1.25, 95% CI, 0.72-2.19) outcome. Propensity-score adjusted Cox proportional regression analysis for first week treatment with cephalosporin demonstrated no significant prognostic impact at 28-days (HR 1.54, 95% CI 0.72-3.23) or 90-days (HR 1.56, 95% CI 0.88-2.86). IN CONCLUSION: There is a comparable effectiveness with respect to 28- and 90-days outcome for first week treatment with ASP versus cephalosporin in MS-SAB. The results indicate that the difference in prognostic impact between first week ASP and cephalosporin may be non-significant in patient cohorts with SAB management optimized by infectious disease specialist consultation.

[Recognize tuberculosis--prevent outbreak]. / Tunnista tuberkuloosi--ehkäise epidemia.

INTRODUCTION: The number of tuberculosis cases in Finland has decreased. Cases among immigrants have, however, increased, and the disease may not be recognized early enough. METHODS: We describe four group exposures to tuberculosis that occurred in Finland, the index patient coming from a country with a high incidence rate of tuberculosis. RESULTS: Over 900 persons were exposed to tuberculosis. Coordination of the surveys was hampered by the fact that several healthcare operators participated in the study. Three index patients had drug-resistant tuberculosis, one of which was multidrug resistant. CONCLUSIONS: Extensive operations of tracking and prevention could have been avoided, if the symptoms would have been recognized earlier.

Predictive Value of C-Reactive Protein (CRP) in Identifying Fatal Outcome and Deep Infections in Staphylococcus aureus Bacteremia.

INTRODUCTION: Clear cut-off levels could aid clinicians in identifying patients with a risk of fatal outcomes or complications such as deep infection foci in Staphylococcus aureus bacteremia (SAB). Cut-off levels for widely used clinical follow-up parameters including serum C-reactive protein (CRP) levels and white blood cell counts (WBC) have not been previously studied. METHODS: 430 adult SAB patients in Finland took part in prospective multicentre study in which their CRP levels and WBC counts were measured on the day of the positive blood culture, every other day during the first week, twice a week during hospitalization and at 30 days. Receiver operating characteristic (ROC) analysis was used to evaluate the prognostic value of CRP and WBC on the day of the positive blood culture and at days 4, 7, and 14 in predicting mortality and the presence of deep infections at 30 days. Adjusted hazard ratios (HR) for CRP level and WBC count cut-off values for mortality were calculated by the Cox regression analysis and adjusted odds ratios (OR) for cut-off values to predict the presence of deep infection by the binary logistic regression analysis. RESULTS: The succumbing patients could be distinguished from the survivors, starting on day 4 after the positive blood culture, by higher CRP levels. Cut-off values of CRP for day 30 mortality in adjusted analysis, that significantly predicted fatal outcome were at day 4 CRP >103 mg/L with sensitivity of 77%, specificity of 55%, and HR of 3.5 (95% CI, 1.2-10.3; p = 0.024), at day 14 CRP >61 mg/L with a sensitivity of 82%, specificity of 80% and HR of 3.6 (95% CI, 1.1-10.3; p<0.039) and cut-off value of WBC at day 14 >8.6 x109/L was prognostic with sensitivity of 77%, specificity of 78% and HR of 8.2 (95% CI, 2.9-23.1; p<0.0001). Cut-off values for deep infection in adjusted analysis were on the day of the positive blood culture CRP >108 mg/L with sensitivity of 77%, specificity of 60%, and HR of 2.6 (95% CI, 1.3-4.9; p = 0.005) and at day 14 CRP >22 mg/L with sensitivity of 59%, specificity of 68%, and HR of 3.9 (95% CI, 1.6-9.5; p = 0.003). The lack of decline of CRP in 14 days or during the second week were neither prognostic nor markers of deep infection focus. CONCLUSIONS: CRP levels have potential for the early identification of SAB patients with a greater risk for death and deep infections.

Improved outcome with early rifampicin combination treatment in methicillin-sensitive Staphylococcus aureus bacteraemia with a deep infection focus - a retrospective cohort study.

INTRODUCTION: Rifampicin has been used as adjunctive therapy in Staphylococcus aureus bacteraemia (SAB) with a deep infection focus. However, data for prognostic impact of rifampicin therapy is unestablished including the optimal initiation time point. We studied the impact of rifampicin therapy and the optimal initiation time for rifampicin treatment on prognosis in methicillin-sensitive S. aureus bacteraemia with a deep infection. METHODS: Retrospective, multicentre study in Finland including 357 SAB patients with a deep infection focus. Patients with alcoholism, liver disease or patients who died within 3 days were excluded. Patients were categorised according to duration of rifampicin therapy and according to whether rifampicin was initiated early (within 7 days) or late (7 days after) after the positive blood cultures. Primary end point was 90 days mortality. RESULTS: Twenty-seven percent of patients received no rifampicin therapy, 14% received rifampicin for 1-13 days whereas 59% received rifampicin ≥14 days. The 90 day mortality was; 26% for patients treated without rifampicin, 16% for rifampicin therapy of any length and 10% for early onset rifampicin therapy ≥14 days. Lack of rifampicin therapy increased (OR 1.89, p=0.026), rifampicin of any duration decreased (OR 0.53, p=0.026) and rifampicin therapy ≥14 days with early onset lowered the risk for a fatal outcome (OR 0.33, p<0.01) during 90 days follow-up. CONCLUSION: Rifampicin adjunctive therapy for at least 14 days and initiated within 7 days of positive blood culture associated with improved outcome among SAB patients with a deep infection.

High cell-free DNA predicts fatal outcome among Staphylococcus aureus bacteraemia patients with intensive care unit treatment.

INTRODUCTION: Among patients with bacteraemia or sepsis the plasma cell-free DNA (cf-DNA) biomarker has prognostic value and Pitt bacteraemia scores predict outcome. We evaluated the prognostic value of plasma cf-DNA in patients with Staphylococcus aureus bacteraemia (SAB) treated in the ICU or in the general ward. METHODS: 418 adult patients with positive blood culture for S. aureus were prospectively followed for 90 days. SAB patients were grouped according to ICU treatment: 99 patients were treated in ICU within 7 days of documented SAB whereas 319 patients were managed outside ICU. Pitt bacteraemia scores were assessed at hospital arrival and cf-DNA was measured at days 3 and 5 from positive blood culture. RESULTS: SAB patients with high Pitt bacteraemia scores and ICU treatment presented higher cf-DNA values as compared to SAB patients with low Pitt bacteraemia scores and non-ICU treatment at both days 3 and 5. Among ICU patients cf-DNA >1.99 µg/ml at day 3 predicted death with a sensitivity of 67% and a specificity of 77% and had an AUC in receiver operating characteristic analysis of 0.71 (p<0.01). The cut-off cf-DNA >1.99 µg/ml value demonstrated a strong association to high Pitt bacteraemia scores (≥ 4 points) (p<0.000). After controlling for all prognostic markers, Pitt bacteraemia scores ≥ 4 points at hospital admission (OR 4.47, p<0.000) and day 3 cf-DNA (OR 3.56, p<0.001) were the strongest factors significantly predicting outcome in ICU patients. cf-DNA at day 5 did not predict fatal outcome. CONCLUSION: High cf-DNA concentrations were observed among patients with high Pitt bacteraemia scores and ICU treatment. Pitt bacteraemia scores (≥ 4 points) and cf-DNA at day 3 from positive blood culture predicted death among SAB patients in ICU and were found to be independent prognostic markers. cf-DNA had no prognostic value among non-ICU patients.

[Tuberculosis is transmitted in hospital and autopsy room--an epidemic in healthcare personnel]. / Tuberkuloosi tarttuu sairaalassa ja ruumiinavaussalissa--terveydenhuollon henkilökunnan epidemia.

We describe an epidemic of tuberculosis of occupational origin in five healthcare workers, which originated from a patient with tuberculous peritonitis. The source of the infection was not revealed until one year after the patient's death. Over 300 workers were exposed to tuberculosis. Up-to-date microbiological molecular technology was applied to the investigation of the infection among the exposed workers. This was the first time that an electronic reporting system for biological exposures was utilized for the investigation of an epidemic. Within this epidemic it is assumed that another five workers will develop a symptomatic tuberculosis infection during their lifetime.

Characterization of infecting strains and superantigen-neutralizing antibodies in Staphylococcus aureus bacteremia.

Staphylococcus aureus superantigens (SAgs) are highly potent T cell mitogens. Antibodies against non-enterotoxin gene cluster (non-egc) SAgs are common in healthy adults, whereas neutralizing antibodies against egc SAgs are rare. We investigated the infecting S. aureus strains and the anti-SAg antibody response during S. aureus bacteremia (SAB). This prospective clinical study (www.clinicaltrials.gov, NCT00548002) included 43 injection drug users (IDUs) and 44 group-matched nonaddicts with SAB. spa genotypes and SAg gene patterns (multiplex PCR) of the S. aureus isolates were determined. The neutralizing capacities of sera obtained at the acute phase and the convalescent phase of SAB were tested against the SAg cocktail of the respective infecting strain and a panel of recombinant SAgs. The lineages CC59 and CC30 were more prevalent among bacteremia strains from IDUs than among strains from nonaddicts. SAg gene patterns in isolates from IDUs and nonaddicts were similar. At the acute phase of bacteremia, IDUs had more neutralizing antibodies against non-egc SAgs than did nonaddicts. Antibody titers frequently increased during infection. In contrast, there were no neutralizing antibodies against egc SAgs at disease onset and such antibodies were not induced by SAB. SAB triggers an antibody response only against non-egc SAgs. Preimmunization in IDU patients is probably due to previous exposure to the infecting strain.

Methicillin-sensitive Staphylococcus aureus bacteraemia and endocarditis among injection drug users and nonaddicts: host factors, microbiological and serological characteristics.

BACKGROUND: Endocarditis has been associated with lower mortality and fewer complications among injection drug users (IDUs) than nonaddicts in Staphylococcus aureus bacteraemia (SAB). The better prognosis of IDUs has not been clarified but it has generally been explained by younger age and other host factors. In this study, bacterial strains, their virulence factors, and host immune responses were compared among IDUs and nonaddicts with SAB, including those with and without endocarditis. METHODS: A total of 430 consecutive adult patients with methicillin-sensitive SAB were followed prospectively for 3 months. All 44 IDUs were included, and 44 nonaddicts as controls for them. According to the modified Duke criteria, 20 patients in both groups had endocarditis. For each addict without endocarditis, an age and sex matched nonaddict was selected as a control. S. aureus isolates were assigned a genotype by PFGE, Panton-Valentine leukocidin (PVL), staphylokinase (SAK), protease, and haemolysin production. Acute and convalescent sera were tested for antibodies to alpha-haemolysin (ASTA) and teichoic acid (TAA). RESULTS: There were no differences between IDUs and nonaddicts with SAB in the proportion of patients with a deep infection (98% vs 86%, P=0.06) or a thromboembolic complication (30% vs 14%, P=0.12). Endocarditis among IDUs was not associated with any specific strains, and only the FIN-4 strain was observed more often in IDUs than in nonaddicts (21% vs 5%, P=0.03). The majority of isolates (98%) were PVL negative, and there were no differences in the numbers of SAK, protease and haemolysin production among strains between IDUs and nonaddicts. However, haemolytic properties were found more frequently in strains from IDUs without endocarditis than those with endocarditis (88% vs 47%, P=0.007). IDUs displayed more often elevated TAA titers than nonaddicts, especially in endocarditis at acute phase (33% vs 5%, P=0.04) and at convalescent phase (50% vs 10%, P=0.01). The ASTA titer was more frequently initially positive among IDUs without endocarditis than with endocarditis (44% vs 6%, P=0.01). CONCLUSIONS: Characterization of the bacterial strains and their virulence factors, and host immune responses did not reveal significant differences between IDUs and nonaddicts with similar clinical picture of SAB. Serological tests were not helpful in identifying patients with endocarditis.

Clinical manifestations and outcome in Staphylococcus aureus endocarditis among injection drug users and nonaddicts: a prospective study of 74 patients.

BACKGROUND: Endocarditis is a common complication in Staphylococcus aureus bacteremia (SAB). We compared risk factors, clinical manifestations, and outcome in a large, prospective cohort of patients with S. aureus endocarditis in injection drug users (IDUs) and in nonaddicts. METHODS: Four hundred and thirty consecutive adult patients with SAB were prospectively followed up for 3 months. Definite or possible endocarditis by modified Duke criteria was found in 74 patients: 20 patients were IDUs and 54 nonaddicts. RESULTS: Endocarditis was more common in SAB among drug abusers (46%) than in nonaddicts (14%) (odds ratio [OR], 5.12; 95% confidence interval [CI], 2.65-9.91; P < 0.001). IDUs were significantly younger (27 +/- 15 vs 65 +/- 15 years, P < 0.001), had less ultimately or rapidly fatal underlying diseases (0% vs 37%, P < 0.001) or predisposing heart diseases (20% vs 50%, P = 0.03), and their SAB was more often community-acquired (95% vs 39%, P < 0.001). Right-sided endocarditis was observed in 60% of IDUs whereas 93% of nonaddicts had left-sided involvement (P < 0.001). An extracardiac deep infection was found in 85% of IDUs and in 89% of nonaddicts (P = 0.70). Arterial thromboembolic events and severe sepsis were also equally common in both groups. There was no difference in mortality between the groups at 7 days, but at 3 months it was lower among IDUs (10%) compared with nonaddicts (39%) (OR, 5.73; 95% CI, 1.20-27.25; P = 0.02). CONCLUSION: S. aureus endocarditis in IDUs was associated with as high complication rates including extracardiac deep infections, thromboembolic events, or severe sepsis as in nonaddicts. Injection drug abuse in accordance with younger age and lack of underlying diseases were associated with lower mortality, but after adjusting by age and underlying diseases injection drug abuse was not significantly associated with mortality.