Evaluation of the STANDARD M10 MDR-TB and MTB/NTM assays for the detection of Mycobacterium tuberculosis, rifampicin and isoniazid resistance, and nontuberculous mycobacteria in a low-incidence setting.

Rapid detection is crucial for tuberculosis (TB) control. GeneXpert (Cepheid) is a widely used PCR system, known for its simplicity, random access, and point-of-care compatibility. SD BIOSENSOR recently introduced a similar system, STANDARD M10, including a Mycobacterium tuberculosis (MTB) and rifampicin (RIF) and isoniazid resistance (herein, MDR-TB) assay and an MTB/nontuberculous mycobacteria (NTM) assay. We evaluated these assays for the potential to replace the established Xpert MTB/RIF Ultra assay in a low-TB incidence setting. We analyzed 160 clinical respiratory samples (45 MTB-positive and 35 NTM-positive) and further 24 drug-resistant MTB, 30 mycobacterial species (2 MTB, 28 NTM), and 37 non-mycobacterial isolates. Compared with culture, clinical sensitivities and specificities for MTB detection were 88.9% (95% confidence interval [CI] = 76.1-95.6%) and 97.4% (CI = 92.3-99.4%) with Xpert Ultra, 88.9% (95% CI = 76.1-95.6%) and 98.3% (CI = 93.5-99.9%) with M10 MDR-TB, and 84.4% (CI = 70.9-94.4%) and 98.3% (CI = 93.5-99.9%) with M10 MTB/NTM, respectively. For NTM detection, M10 MTB/NTM showed sensitivity and specificity of 65.7% (CI = 49.1-79.2%) and 96.8% (CI = 91.8-99.0%). Compared with phenotypic drug susceptibility testing (DST), sensitivity and specificity for detecting RIF resistance were 100% (CI = 77.3-100%) and 95.6% (CI = 84.4-99.6%) with Xpert Ultra, and 100% (CI = 74.9-100%) and 95.5% (CI = 84.0-99.6%) with M10 MDR-TB. M10 MDR-TB showed 92.3% sensitivity (CI = 74.7-99.0%) and 100% specificity (CI = 87.3-100%) for detecting isoniazid resistance. All discrepancies in DST by PCR were concordant with whole-genome sequencing. While M10 MDR-TB demonstrated great potential as an alternative to Xpert Ultra, M10 MTB/NTM had limitations in NTM screening. Additionally, the M10 sputum pretreatment did not inactivate MTB efficiently, which should be considered in process risk assessment. IMPORTANCE: The molecular diagnostic STANDARD M10 system is highly analogous to the widely established GeneXpert system, which significantly increases the relevance of this evaluation study in the field of rapid detection of M. tuberculosis. To our knowledge, this is the first clinical evaluation describing the performance of the STANDARD M10 MDR-TB and MTB/NTM assays, including an extensive analytical specificity panel (inclusivity and exclusivity) for the detection of M. tuberculosis, drug resistance, and nontuberculous mycobacteria.

Novel Biomarkers: Soluble Urokinase-Type Plasminogen Activator Receptor and Procalcitonin- and Histological Chorioamnionitis after Preterm Premature Rupture of Membranes.

Fetal inflammatory response syndrome or infection after preterm premature rupture of membranes (PPROM) increases neonatal morbidity in preterm deliveries. Biochemical markers from the amniotic fluid (AF) have been used to evaluate possible intra-amniotic infection during the asymptomatic phase after PPROM. This study aimed to describe whether soluble urokinase-type plasminogen activator receptor (suPAR) or procalcitonin (PCT) from AF or maternal sera could reveal fetal inflammatory response or infection after PPROM. AF and maternal serum samples were collected weekly after PPROM (23+ 0 - 34+ 6 gestational weeks) until delivery from twenty women and two women with possible chorioamnionitis with intact membranes. Levels of suPAR, PCT, interleukin-6 (IL-6), glucose, lactate dehydrogenase (LDH), and bacterial PCR were determined from AF and suPAR and PCT and IL-6 from maternal sera. Fetal infection or inflammation response were determined by the histology of the placenta after delivery. AF glucose was significantly lower and AF LDH higher in the fetal site histologic chorioamnionitis (HCA) group, while AF suPAR concentrations tended to be higher in this group. AF suPAR correlated significantly with AF glucose and LDH. Based on receiver operating characteristic (ROC) analysis, AF glucose had the best predictability for fetal site histological chorioamnionitis. The findings of AF PCT were insignificant considering HCA. AF glucose had the highest accuracy in predicting fetal site histologic chorioamnionitis. AF suPAR may be a promising marker; however, our findings were limited by a small study population.

Assessment of a novel BLOOMY score for predicting mortality in hospitalised adults with bloodstream infection.

PURPOSE: A German multicentre study BLOOMY was the first to use machine learning approach to develop mortality prediction scores for bloodstream infection (BSI) patients, but the scores have not been assessed in other cohorts. Our aim was to assess how the BLOOMY 14-day and 6-month scores estimate mortality in our cohort of 497 cases with BSI. METHODS: Clinical data, laboratory data, and patient outcome were gathered retrospectively from patient records. The scores were calculated as presented in the BLOOMY study with the exception in the day of the evaluation. RESULTS: In our cohort, BLOOMY 14-day score estimated death by day 14 with an area under curve (AUC) of 0.87 (95% Confidence Interval 0.80-0.94). Using ≥ 6 points as a cutoff, sensitivity was 68.8%, specificity 88.1%, positive predictive value (PPV) 39.3%, and negative predictive value (NPV) 96.2%. These results were similar in the original BLOOMY cohort and outweighed both quick Sepsis-Related Organ Failure Assessment (AUC 0.76) and Pitt Bacteraemia Score (AUC 0.79) in our cohort. BLOOMY 6-month score to estimate 6-month mortality had an AUC of 0.79 (0.73-0.85). Using ≥ 6 points as a cutoff, sensitivity was 98.3%, specificity 10.7%, PPV 25.7%, and NPV 95.2%. AUCs of 6-month score to estimate 1-year and 5-year mortality were 0.80 (0.74-0.85) and 0.77 (0.73-0.82), respectively. CONCLUSION: The BLOOMY 14-day and 6-month scores performed well in the estimations of mortality in our cohort and exceeded some established scores, but their adoption in clinical work remains to be seen.

Streptococcus intermedius causing primary bacterial ventriculitis in a patient with severe periodontitis - a case report.

BACKGROUND: Streptococcus intermedius is a member of the S. anginosus group and is part of the normal oral microbiota. It can cause pyogenic infections in various organs, primarily in the head and neck area, including brain abscesses and meningitis. However, ventriculitis due to periodontitis has not been reported previously. CASE PRESENTATION: A 64-year-old male was admitted to the hospital with a headache, fever and later imbalance, blurred vision, and general slowness. Neurological examination revealed nuchal rigidity and general clumsiness. Meningitis was suspected, and the patient was treated with dexamethasone, ceftriaxone and acyclovir. A brain computer tomography (CT) scan was normal, and cerebrospinal fluid (CSF) Gram staining and bacterial cultures remained negative, so the antibacterial treatment was discontinued. Nine days after admission, the patient's condition deteriorated. The antibacterial treatment was restarted, and a brain magnetic resonance imaging revealed ventriculitis. A subsequent CT scan showed hydrocephalus, so a ventriculostomy was performed. In CSF Gram staining, chains of gram-positive cocci were observed. Bacterial cultures remained negative, but a bacterial PCR detected Streptococcus intermedius. An orthopantomography revealed advanced periodontal destruction in several teeth and periapical abscesses, which were subsequently operated on. The patient was discharged in good condition after one month. CONCLUSIONS: Poor dental health can lead to life-threatening infections in the central nervous system, even in a completely healthy individual. Primary bacterial ventriculitis is a diagnostic challenge, which may result in delayed treatment and increased mortality.

Evaluation of the FluoroType Mycobacteria assay for identification of mycobacteria.

Accurate species identification is a prerequisite for successful management of tuberculosis and non-tuberculous mycobacterial (NTM) diseases. The novel FluoroType Mycobacteria assay combines three established GenoType DNA strip assays (CM, AS, and NTM-DR), allowing detection of Mycobacterium tuberculosis and 32 NTM species/subspecies in a single assay with automatic detection and result analysis. We evaluated the clinical performance of the FluoroType assay and its feasibility in replacing the GenoType Mycobacterium CM assay as the initial method for mycobacterial identification. A total of 191 clinical mycobacterial cultures were analyzed in this study: 180 identified for one mycobacterial species, 6 for multiple, and 5 for no mycobacterial species. Positive percent agreement (PPA) for the FluoroType assay was 87.8% (n = 158), with full agreement for 23/29 species. Weakest PPA was observed for Mycobacterium gordonae (50%, n = 9/18), Mycobacterium interjectum (40%, n = 2/5), and Mycobacterium intracellulare (42%, n = 5/12). Clinical and mixed cultures containing multiple mycobacterial species gave equally single species and genus level identifications (n = 30). No cross-reactivity with non-mycobacterial species was observed (n = 22). In a separate in silico analysis of 2016-2022 HUS area (Finland) register data (n = 2,573), the FluoroType assay was estimated to produce 18.8% (n = 471) inadequate identifications (genus/false species) if used as the primary identification method compared to 14.2% (n = 366) with the GenoType CM assay. The FluoroType assay was significantly more convenient in terms of assay workflow and result interpretation compared to the entirely manual and subjective GenoType CM assay. However, the feasibility of the assay should be critically assessed with respect to the local NTM species distribution. IMPORTANCE: This study is the first clinical evaluation report of the novel FluoroType Mycobacteria assay. The assay has the potential to replace the established GenoType NTM product family in identification of culture-enriched mycobacteria. However, our research results suggest that the assay performs suboptimally and may not be feasible for use in all clinical settings.

P-suPAR may reflect the inflammatory response after pancreatic surgery.

BACKGROUND: Several different scoring systems have been developed to predict post-pancreatectomy complications. Currently used inflammatory markers are of only limited value in predicting complications after pancreatic surgery. Plasma soluble urokinase plasminogen activator receptor (P-suPAR) is a prognostic biomarker associated with different inflammatory conditions. The aim of this study was to investigate P-suPAR levels before and after pancreatic surgery. METHODS: One hundred and seventy-six patients evaluated for pancreatic surgery due to suspected malignant or premalignant lesion were recruited for this study at Tampere University Hospital between 2016 and 2021. P-suPAR was analyzed before the planned operation and on postoperative days (PODs) one and three. RESULTS: One hundred and thirty-three patients [median age 67 (range 33-84) years, 50 % male] underwent a pancreatic surgery procedure. Compared to preoperative values [median 3.7 (IQR 3.1-4.7) ng/mL], P-suPAR was significantly lower on PODs 1 [3.2 (2.5-3.9) ng/mL; p < 0.001] and 3 [3.2 (2.7-4.1) ng/mL; p < 0.001]. P-suPAR on POD 1 was significantly lower in patients with postoperative pancreatic fistula (POPF) [2.6 (2.1-3.4) ng/mL] than in patients with no POPF [3.2 (2.6-3.8) ng/mL; p = 0.007]. Similar decreases in P-suPAR values were seen in patients with postoperative acute pancreatitis (POAP) and surgical site infection (SSI). CONCLUSIONS: After pancreatic surgery, P-suPAR level on POD 1 is significantly lower in patients with POPF, POAP or SSI. P-suPAR is decreased after pancreatic resection in all patients. This type of postoperative P-suPAR profile has not previously been described, and may reflect the compensatory anti-inflammatory reaction following the initial systemic inflammatory reaction caused by surgical trauma.

Evaluation of the new 2.0 version of the Roche SARS-CoV-2 Rapid Antigen Test.

We evaluated the new 2.0 version of the Roche Diagnostics SARS-CoV-2 Rapid Antigen Test (RAT 2.0) for the detection of SARS-CoV-2. Our evaluation material comprised of nasopharyngeal samples of 140 persons positive for SARS-CoV-2 nucleic acid amplification test (NAAT) and of 100 persons negative for SARS-CoV-2 NAAT. The sensitivity limit of the RAT 2.0 was further estimated with the additional selected samples of 27 persons with high NAAT cycle threshold (Ct) value representing low viral load. For the detection of possible cross-reactions in the RAT 2.0, routine respiratory samples positive for influenza A (N = 5), respiratory syncytial virus (RSV) (N = 4), or combined RSV and human coronavirus OC43 (N = 1) were included in the study material. The overall sensitivity of the RAT 2.0 was 92.1% and specificity 100%. When evaluating the samples with NAAT Ct value ≤ 30, the sensitivity was 97.0%. All samples for cross-reactivity testing containing other viruses instead of SARS-CoV-2 remained negative in RAT 2.0. According to our findings, this RAT 2.0 offers a reliable tool for the diagnostics of acute COVID-19 in this pandemic environment.

Incidence, seasonal pattern, and clinical manifestations of Streptococcus dysgalactiae subspecies equisimilis bacteremia; a population-based study.

Streptococcus dysgalactiae subspecies equisimilis (SDSE) is a human pathogen causing severe invasive infections. Population-based studies on SDSE bacteremia are limited. The purpose of this study was to investigate the incidence, seasonal pattern, clinical manifestations, and recurrence of SDSE bacteraemia. Records regarding patients aged ≥ 18 years with SDSE bacteremia in the Pirkanmaa health district in August 2015 to July 2018 were retrospectively reviewed. A total of 230 SDSE bacteremia episodes were identified, with 217 episodes (involving 211 patients) available for analysis. The mean annual incidence rate of SDSE bacteremia was 16.9/100 000 inhabitants. Most episodes (33%) were detected in the summer (June to August) (p = 0.058). Episodes with bacteremic cellulitis were statistically significantly more common during the summer compared with other seasons (p = 0.008). Cellulitis was the most common presenting clinical manifestation of SDSE bacteremia (68% of all episodes). Risk factors of recurring bacteremia were chronic eczema and/or skin erosion (OR 3.96 [95% CI 1.11-14.1]), heart disease (OR 3.56 [95% CI 1.22-10.4]), diabetes (OR 3.77 [95% CI 1.35-10.5]) and a history of cellulitis. We found a remarkably high incidence of SDSE bacteraemia in the Pirkanmaa health district. Bacteraemic cellulitis, which was the predominant clinical manifestation is more often occurred in the summer. Risk factors of recurring SDSE bacteremia were a history of cellulitis, chronic eczema or skin erosion, diabetes, and heart disease.

Major risk factors for Streptococcus dysgalactiae subsp. equisimilis bacteremia: a population-based study.

BACKGROUND: Streptococcus dysgalactiae subspecies equisimilis is a human pathogen causing severe invasive infections. Detailed information on S. dysgalactiae subsp. equisimilis bacteremia and especially of predisposing factors are lacking. The purpose of the study is to investigate the risk factors of S. dysgalactiae subsp. equisimilis bacteremia compared to the general population in Finland. METHODS: We retrospectively reviewed all patients older than 18 years with S. dysgalactiae subsp. equisimilis bacteremia in the Pirkanmaa health district from August 2015 to July 2018. The risk factors for S. dysgalactiae subsp. equisimilis bacteremia were investigated with respect to the normal population in Finland using the Finhealth study data provided by the Finnish institute for health and welfare. The study group was matched with the Finhealth study by age and sex. RESULTS: Altogether 230 cases of S. dysgalactiae subsp. equisimilis bacteremia were detected. The medical records of 217 episodes of S. dysgalactiae subsp. equisimilis bacteremia (involving 211 patients) were available for analysis. Obesity was a statistically significant risk factor for S. dysgalactiae subsp. equisimilis bacteremia (Odds Ratio 2.96 [95% CI 2.22-3.96]). Diabetes and coronary artery disease were also associated with an increased risk of S. dysgalactiae subsp. equisimilis bacteremia (OR 4.82 [95% CI 3.62-6.42]) and (OR 3.03 [95% CI 2.18-4.19]). CONCLUSIONS: We found obesity, diabetes, and coronary artery disease to be associated with an increased risk for S. dysgalactiae subsp. equisimilis bacteremia. These results provide an increased understanding of risk factors for S. dysgalactiae subsp. equisimilis bacteremia.

Plasma soluble urokinase-type plasminogen activator receptor (P-suPAR) in the diagnostics between malignant and non-malignant pancreatic lesions.

BACKGROUND: Soluble urokinase-type plasminogen activator receptor (suPAR) is a biomarker elevated in several inflammatory conditions and cancers. It has recently been shown to be elevated in pancreatic ductal adenocarcinoma (PDAC). Plasma suPAR (P-suPAR) predicts the severity of the disease in first acute alcohol-induced pancreatitis (AAP) and ten-year mortality after recovery from first AAP. According to our previous results, P-suPAR is not elevated in chronic pancreatitis (CP) and could possibly be used in distinguishing pancreatic cancer (PC) from CP. When imaging creates a suspicion of a pancreatic lesion, the distinction between malignant and non-malignant disease is crucial. Additional tools are needed, and we still lack a sufficiently sensitive and specific biomarker. Our aim was to further investigate whether preoperatively measured P-suPAR is beneficial in distinguishing between malignant and non-malignant pancreatic lesions. METHODS: One hundred and seventy-six patients evaluated in Tampere University Hospital for pancreatic surgery for suspected malignant pancreatic lesion were recruited for the study. The final study group consisted of 113 patients. P-suPAR and other covariates were measured before the planned operation. RESULTS: P-suPAR was significantly higher in patients with pancreatic cancer (PC) [median 4.1 (IQR 3.3-5.1) ng/mL] than in patients with non-malignant [3.3 (2.9-4.4) ng/mL; p = 0.012] histology. ROC curve analysis resulted in an AUC of 0.65 (95% CI 0.55-0.76); p = 0.007 and a cutoff value of 3.2 ng/mL. Crosstabulation yielded sensitivity of 82% and specificity of 43%. A combination of positive P-suPAR and elevated plasma carbohydrate antigen 19-9 (P-CA19-9) tests did not improve sensitivity but elevated specificity up to 86-88%. CONCLUSIONS: Preoperative P-suPAR is elevated in patients with PC compared to patients with a non-malignant pancreatic lesion. Combining P-suPAR with P-CA19-9 may improve diagnostic accuracy.

Nasal nitric oxide is decreased in acute mild COVID-19 and related to viral load.

Gaseous nitric oxide levels from the lungs (FeNO) and from the nose (nNO) have been demonstrated to react to acute infection or influenza vaccination. There are no published data on nNO levels during acute COVID-19, but normal levels of FeNO have been reported in one study. Our aim was to assess if acute mild COVID-19 alters nasal or bronchial NO output at the time of acute infection and at a two-month follow up, and if this is related to symptoms or viral load. This study included 82 subjects with mild acute airway infection who did not need hospitalization: 43 cases (reverse transcription polymerase chain reaction (RT-PCR)-positive for SARS-CoV-2 in routine testing from nasopharynx) and 39 age- (±5 years) and gender-matched controls (RT-PCR-negative for SARS-CoV-2). During acute infection, the cases had lower nNO compared to controls (158 [104-206] vs. 232 [203-279] nl min-1;p< 0.001), but after two months, there was no significant difference between the groups (230 [179-290] vs. 268 [222-320] nl min-1;p= 0.162). There was no difference in FeNO between the groups at either of the visits. Nasal NO correlated with the cycle threshold (Ct) value of the nasopharyngeal RT-PCR test for SARS-CoV-2 (Spearman'srs= 0.550;p< 0.001), that is, nNO was lower with a higher viral load. Nasal NO output was decreased in acute COVID-19 in relation to higher viral load, suggesting that the type and intensity of inflammatory response affects the release of NO from airway mucosa. In these subjects without significant lower airway involvement, there were no clinically relevant findings regarding FeNO.

Evaluation of the Roche-SD Biosensor rapid antigen test: Antigen is not reliable in detecting SARS-CoV-2 at the early stage of infection with respiratory symptoms.

We evaluated a rapid antigen test against SARS-CoV-2 virus (Roche-SD Biosensor; RSDB-RAT) in children and adults with respiratory symptoms compared to those with nonrespiratory symptoms or asymptomatic. Also the performance of RSDB-RAT with respect to the duration of respiratory symptoms was assessed. A viral cross-reactivity panel was included. RSDB-RAT was reliable in detecting SARS-CoV-2 in children and adults if the respiratory symptoms had endured 1 to 7 days. If the respiratory symptoms had lasted less than 1 day, the sensitivity was significantly lower. No cross-reactivity with other respiratory viruses was observed.

Sampling site for SARS-CoV-2 RT-PCR-An intrapatient four-site comparison from Tampere, Finland.

BACKGROUND: SARS-CoV-2 diagnosis relies on the performance of nasopharyngeal swabs. Alternative sample sites have been assessed but the heterogeneity of the studies have made comparing different sites difficult. OBJECTIVES: Our aim was to compare the performance of four different sampling sites for SARS-CoV-2 samples with nasopharynx being the benchmark. STUDY DESIGN: COVID-19 positive patients were recruited prospectively, and samples were collected and analysed for SARS-CoV-2 with RT-PCR from all four anatomical sites in 43 patients, who provided written informed consent. RESULTS: All anterior nasal and saliva samples were positive, while two oropharyngeal samples were negative. There was no significant difference in the cycle threshold values of nasopharyngeal and anterior nasal samples while saliva and oropharynx had higher cycle threshold values. CONCLUSIONS: Anterior nasal swab performs as good as nasopharynx swab with saliva also finding all the positives but with higher cycle threshold values. Thus, we can conclude that anterior nasal swabs can be used for SARS-CoV-2 detection instead of nasopharyngeal swabs if the situation would require so.

Comparison of 2 fully automated tests detecting antibodies against nucleocapsid N and spike S1/S2 proteins in COVID-19.

Automated assays for detecting severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibodies in coronavirus disease 2019 (COVID-19) diagnostics have recently come available. We compared the performance of the Elecsys® Anti-SARS-CoV-2 and LIAISON® SARS-CoV-2 S1/S2 IgG tests. The seroconversion panel comprised of 120 samples from 13 hospitalized COVID-19 patients. For the sensitivity and specificity testing, samples from COVID-19 outpatients >15 days after positive nucleic acid amplification test (NAAT) result (n = 35) and serum control samples collected before the COVID-19 era (n = 161) were included in the material. Samples for the detection of possible cross-reactions were also tested. Based on our results, the SARS-CoV-2 antibodies can be quite reliably detected 2 weeks after NAAT positivity and 3 weeks after the symptom onset with both tests. However, since some COVID-19 patients were positive only with Elecsys®, the antibodies should be screened against N-antigen (Elecsys®) and reactive samples confirmed with S antigen (LIAISON®), but both results should be reported. In some COVID-19 patients, the serology can remain negative.

Plasma suPAR may help to distinguish between chronic pancreatitis and pancreatic cancer.

OBJECTIVES: SuPAR (soluble urokinase-type plasminogen activator receptor) is a biomarker reflecting the inflammatory state of the human body. Earlier studies suggest that urinary suPAR/creatinine ratio levels are elevated in chronic pancreatitis (CP), and that plasma suPAR (P-suPAR) level is elevated in pancreatic cancer (PC). Our aim was to study the levels of P-suPAR in CP in a long-term prospective follow-up setting to explore the possibility of distinguishing between PC and CP. MATERIALS AND METHODS: Two patient groups were compared. The first group included 83 patients who were prospectively followed up after their first acute alcohol-induced pancreatitis (AAP) for median 7.0 (range 0.3-9.8) years. Twelve patients in this group developed CP during follow-up, and two patients were further excluded from the CP cohort. The second group consisted of 25 patients operated on for suspicion of pancreatic malignancy and final pathological diagnosis of PC. P-suPAR levels were measured and compared within and between these groups. RESULTS: P-suPAR levels remained low during follow-up despite the development of CP. P-suPAR was significantly higher in PC patients [median 3.7 (IQR 3.1-4.4) ng/mL] than in CP patients [2.6 (1.8-3.6) ng/mL]; p = .014. A cutoff value of 2.8 ng/mL resulted from a ROC curve with area under curve (AUC) of 0.79 (95% CI 0.61-0.97), p = .009 in differentiation between PC and CP with a sensitivity and a specificity of 88% and 70% respectively. CONCLUSION: P-suPAR is higher in patients with PC than in patients with CP, and it could thus be used in differentiating between PC and CP.

Differential mobility spectrometry classification of bacteria.

Aim: Rapid identification of bacteria would facilitate timely initiation of therapy and improve cost-effectiveness of treatment. Traditional methods (culture, PCR) require reagents, consumables and hours to days to complete the identification. In this study, we examined whether differential mobility spectrometry could classify most common bacterial species, genera and between Gram status within minutes. Materials & methods: Cultured bacterial sample gaseous headspaces were measured with differential mobility spectrometry and data analyzed using k-nearest-neighbor and leave-one-out cross-validation. Results: Differential mobility spectrometry achieved a correct classification rate 70.7% for all bacterial species. For bacterial genera, the rate was 77.6% and between Gram status, 89.1%. Conclusion: Largest difficulties arose in distinguishing bacteria of the same genus. Future improvement of the sensor characteristics may improve the classification accuracy.

Chlamydia trachomatis samples testing falsely negative in the Aptima Combo 2 test in Finland, 2019.

Since February 2019, over 160 Chlamydia trachomatis (CT) cases testing negative or equivocal by Aptima Combo 2 (AC2) but positive by Aptima CT test run with Panther instruments occurred in Finland. The AC2 test targets chlamydial 23S rRNA while the CT test targets 16S rRNA. Sequencing of 10 strains revealed a nucleotide substitution in 23S rRNA. The significance of this for the failure of the AC2 test to detect the variant is not yet known.

Antibody response to the 23-valent pneumococcal polysaccharide vaccine after conjugate vaccine in patients with chronic lymphocytic leukemia.

The 23-valent pneumococcal polysaccharide vaccine (PPV23) given alone is ineffective in patients with chronic lymphocytic leukemia (CLL) and better antibody response is achieved with pneumococcal conjugate vaccines (PCVs). In this study, we determine whether CLL patients would achieve a significant antibody response and broaden their serotype coverage against invasive pneumococcal disease (IPD) with PPV23 given five years after the 7-valent conjugate vaccine (PCV7). A total of 24 patients with CLL and eight controls were vaccinated with PPV23 five years after PCV7. Blood samples for evaluation of antibody response to PCV7 serotypes and PPV23 serotypes 5 and 7 were taken before vaccination and one month after it. Post-vaccination samples were available from 20 patients. IgG antibodies were measured with ELISA. Antibody concentrations after PPV23 were significantly lower in CLL patients for six of the PCV7 serotypes and for both PPV23 serotypes. Only 10% to 15% of CLL patients achieved an antibody response suggested to be protective against IPD. Hence, PCV7 given five years before PPV23 did not improve antibody response in patients with CLL. Based on our results, PPV23 given after a PCV primer is not useful against IPD in CLL patients.