Carl Spindler

Clonal and Capsular Types Decide Whether Pneumococci Will Act as a Primary or Opportunistic Pathogen

BACKGROUND Streptococcus pneumoniae is a major cause of morbidity and mortality worldwide. The role of the different capsular and clonal types in invasive disease severity remains to be defined. METHODS Disease severity and disease type were correlated to age, underlying disease, capsular serotype, and clonal type of the causative agent for 494 adult patients with invasive pneumococcal disease. RESULTS Pneumococcal isolates of serotypes 1 and 7F were genetically homogenous, had the highest potential to infect previously healthy individuals, and were not causing deaths. Also, type 1 isolates were only found among younger adults, whereas other serotypes were mainly found among elderly persons (e.g., type 23F). Some serotypes and/or clones were more prone to cause more-severe disease, as observed by high APACHE II scores calculated at admission, and were also associated with a high mortality (e.g., clones of type 3 and 11A). We found no evidence of an impact of penicillin resistance on disease severity and disease type. CONCLUSIONS We suggest that clones with capsular types 1 and 7F, which are known to have a high invasive disease potential, behave as primary pathogens, whereas clones with other capsular types with a lower relative risk of causing invasive disease are more opportunistic, primarily affecting patients with underlying disease. Disease caused by the latter group, however, was more severe, even in previously healthy individuals.

Swedish guidelines on the management of community-acquired pneumonia in immunocompetent adults-Swedish Society of Infectious Diseases 2012

Abstract This document presents the 2012 evidence based guidelines of the Swedish Society of Infectious Diseases for the in- hospital management of adult immunocompetent patients with community-acquired pneumonia (CAP). The prognostic score ‘CRB-65’ is recommended for the initial assessment of all CAP patients, and should be regarded as an aid for decision-making concerning the level of care required, microbiological investigation, and antibiotic treatment. Due to the favourable antibiotic resistance situation in Sweden, an initial narrow-spectrum antibiotic treatment primarily directed at Streptococcus pneumoniae is recommended in most situations. The recommended treatment for patients with severe CAP (CRB-65 score 2) is penicillin G in most situations. In critically ill patients (CRB-65 score 3–4), combination therapy with cefotaxime/macrolide or penicillin G/fluoroquinolone is recommended. A thorough microbiological investigation should be undertaken in all patients, including blood cultures, respiratory tract sampling, and urine antigens, with the addition of extensive sampling for more uncommon respiratory pathogens in the case of severe disease. Recommended measures for the prevention of CAP include vaccination for influenza and pneumococci, as well as smoking cessation.

Prognostic score systems and community-acquired bacteraemic pneumococcal pneumonia

The aim of this study was to evaluate the accuracy of three score systems: the pneumonia severity index (PSI); CURB-65 (confusion; urea >7 mM; respiratory rate ≥30 breaths·min-1; blood pressure <90 mmHg systolic or ≤60 mmHg diastolic; aged ≥65 yrs old); and modified American Thoracic Society rule for predicting intensive care unit (ICU) need and mortality due to bacteraemic pneumococcal pneumonia. All adult patients (n = 114) with invasive pneumococcal pneumonia at the Karolinska University Hospital, Sweden, 1999–2000, were included in the study. Severity scores were calculated and the independent prognostic importance of different variables was analysed by multiple regression analyses. PSI ≥IV, CURB-65 ≥2, and the presence of one major or more than one minor risk factor in mATS all had a high sensitivity, but somewhat lower specificity for predicting death and ICU need. The death rate was 12% (13 out of 114). Severity score and treatment in departments other than the Dept of Infectious Diseases were the only factors independently correlated to death. Patients treated in other departments more often had severe underlying illnesses and were more severely ill on admission. However, a significant difference in death rates remained after adjustment for severity between the two groups. In conclusion, all score systems were useful for predicting the need for intensive care unit treatment and death due to bacteremic pneumococcal pneumonia. The pneumonia severity index was the most sensitive, but CURB-65 was easier to use.

Effects of a large-scale introduction of the pneumococcal polysaccharide vaccine among elderly persons in Stockholm, Sweden

In October 1998 Stockholm County launched a 3-year vaccination campaign with the 23-valent pneumococcal polysaccharide vaccine (PPV-23) directed towards all elderly persons. We analysed the impact of this campaign on the incidence and serotype distribution of invasive pneumococcal disease (IPD) in Stockholm County, where the vaccine coverage was 36%, as compared to Skåne County, where no vaccination campaign was performed. The incidence of vaccine-type IPD in Stockholm declined significantly during the study period (1997-2001) in elderly persons, from 50 to 28.9/100,000, but not in other age groups in Stockholm, nor in any age group in Skåne.

Clinical manifestations of invasive pneumococcal disease by vaccine and non-vaccine types.

Pneumococcal conjugated vaccines (PCVs) have shown protection against invasive pneumococcal disease by vaccine serotypes, but an increase in non-vaccine serotype disease has been observed. Type-specific effects on clinical manifestation need to be explored. Clinical data from 2096 adults and 192 children with invasive pneumococcal disease were correlated to pneumococcal molecular serotypes. Invasive disease potential for pneumococcal serotypes were calculated using 165 invasive and 550 carriage isolates from children. The invasive disease potential was lower for non-PCV13 compared to vaccine-type strains. Patients infected with non-PCV13 strains had more underlying diseases, were less likely to have pneumonia and, in adults, tended to have a higher mortality. Furthermore, patients infected with pneumococci belonging to clonal serotypes only expressing non-PCV13 capsules had a higher risk for septicaemia and mortality. PCV vaccination will probably lead to a decrease in invasive pneumococcal disease but an alteration in the clinical manifestation of invasive pneumococcal disease. Genetic lineages causing invasive pneumococcal disease in adults often express non-vaccine serotypes, which can expand after vaccination with an increased risk of infection in patients with underlying diseases. Pneumococcal non-vaccine type strains cause severe disease, but with different spectrums of clinical manifestations http://ow.ly/ABYnz

The IRIDICA PCR/Electrospray Ionization-Mass Spectrometry Assay on Bronchoalveolar Lavage for Bacterial Etiology in Mechanically Ventilated Patients with Suspected Pneumonia.

We studied the diagnostic performance of the IRIDICA PCR/electrospray ionization–mass spectrometry (PCR/ESI-MS) assay applied on bronchoalveolar lavage (BAL) samples, from 51 mechanically ventilated patients with suspected pneumonia, in a prospective study. In 32 patients with X-ray verified pneumonia, PCR/ESI-MS was positive in 66% and BAL culture was positive in 38% (p = 0.045), and either of the methods was positive in 69%. The following BAL result combinations were noted: PCR/ESI-MS+/culture+, 34%; PCR/ESI-MS+/culture-, 31%; PCR/ESI-MS-/culture+, 3.1%; PCR/ESI-MS-/culture-, 31%; kappa 0.36 (95% confidence interval (CI), 0.10–0.63). In pneumonia patients without prior antibiotic treatment, optimal agreement was noted with 88% PCR/ESI-MS+/culture+ and 12% PCR/ESI-MS-/culture- (kappa 1.0). However, in patients with prior antibiotic treatment, the test agreement was poor (kappa 0.16; 95% CI, -0.10–0.44), as 10 patients were PCR/ESI-MS+/culture-. In 8/10 patients the pathogens detected by PCR/ESI-MS could be detected by other conventional tests or PCR tests on BAL. Compared with BAL culture, PCR/ESI-MS showed specificities and negative predictive values of ≥87% for all individual pathogens, an overall sensitivity of 77% and positive predictive value (PPV) of 42%. When other conventional tests and PCR tests were added to the reference standard, the overall PPV increased to 87%. The PCR/ESI-MS semi-quantitative level tended to be higher for PCR/ESI-MS positive cases with pneumonia compared with cases without pneumonia (p = 0.074). In conclusion, PCR/ESI-MS applied on BAL showed a promising performance and has potential to be clinically useful in mechanically ventilated patients with suspected pneumonia. The usefulness of the method for establishment of pneumonia etiology and selection of antibiotic therapy should be further studied.

Transthoracic fine-needle aspiration in the aetiological diagnosis of community-acquired pneumonia

Abstract To investigate the safety and practicability of conducting transthoracic fine-needle aspiration (TFNA) in a general hospital setting, we applied the TFNA procedure to 20 patients hospitalized with community-acquired pneumonia (CAP) within 36 h of admission. Also, a preliminary assessment was made of the potential value of adding TFNA to conventional methods of diagnostic microbiology. TFNA was easy to perform and caused little discomfort, and no serious adverse events were observed. In spite of ongoing antimicrobial treatment, a likely aetiological diagnosis was established for 14 of 20 (70%) of the patients. TFNA may provide important additional information on the aetiology of CAP.

Developing a decision support system for patients with severe infection conditions in pre-hospital care

OBJECTIVE To develop and validate a pre-hospital decision support system (DSS) for the emergency medical services (EMS), enabling the identification and steering of patients with critical infectious conditions (i.e., severe respiratory tract infections, severe central nervous system (CNS) infections, and sepsis) to a specialized emergency department (ED) for infectious diseases. METHODS The development process involved four consecutive steps. The first step was gathering data from the electronic patient care record system (ePCR) on patients transported by the EMS, in order to identify retrospectively appropriate patient categories for steering. The second step was to let a group of medical experts give advice and suggestions for further development of the DSS. The third and fourth steps were the evaluation and validation, respectively, of the whole pre-hospital DSS in a pilot study. RESULTS A pre-hospital decision support tool (DST) was developed for three medical conditions: severe respiratory infection, severe CNS infection, and sepsis. The pilot study included 72 patients, of whom 60% were triaged to a highly specialized emergency department (ED-Spec) with an attending infectious disease physician (ID physician). The results demonstrated that the pre-hospital emergency nurses (PENs) adhered to the DST in 66 of 72 patient cases (91.6%). For those patients steered to the ED-Spec, the assessment made by PENs and the ID physician at the ED was concordant in 94% of cases. CONCLUSIONS The development of a specific DSS aiming to identify patients with three different severe infectious diseases appears to give accurate decision support to PENs when steering patients to the optimal level of care.

Management of community-acquired pneumonia in immunocompetent adults : updated Swedish guidelines 2017

Abstract Based on expert group work, Swedish recommendations for the management of community-acquired pneumonia in adults are here updated. The management of sepsis-induced hypotension is addressed in detail, including monitoring and parenteral therapy. The importance of respiratory support in cases of acute respiratory failure is emphasized. Treatment with high-flow oxygen and non-invasive ventilation is recommended. The use of statins or steroids in general therapy is not found to be fully supported by evidence. In the management of pleural infection, new data show favourable effects of tissue plasminogen activator and deoxyribonuclease installation. Detailed recommendations for the vaccination of risk groups are afforded.