Periodontal infections and community-acquired pneumonia: a case–control study

The aim of this study was to evaluate if the presence of periodontal infections (PI) is associated with community-acquired pneumonia (CAP) in a group of patients admitted to a hospital. A total of 140 patients were enrolled in this case–control study, with 70 patients having CAP (case group) and the other 70 patients diagnosed with other systemic diseases (control group). A periodontal examination was carried out to assess pocket probing depth (PPD), clinical attachment loss (CAL), bleeding on probing (BOP), and presence of bacterial plaque (BP). CAL and BOP showed higher scores in the case group over the control group. They were, respectively, 3.16?±?2.43 mm and 0.33?±?0.24 % for the case group, and 1.99?±?2.23 mm and 0.25?±?0.24 % for the control group (p?<?0.05). High scores for BP were observed in both groups (case: 97.1 %; control: 98.6 %, p?=?1.0000). Chronic periodontitis (CP) was more frequent in patients with CAP (case: 61.4 %; control: 41.4 %). The presence of moderate or severe CP increased the risk for CAP [odds ratio (OR)?=?4.4, 95 % confidence interval (CI)?=?1.4–13.8], even when adjusted for age, ethnicity, gender, and smoking. Moderate and severe chronic periodontitis were associated with CAP in this study.     

Risk factors for Cutibacterium acnes spinal implant-associated infection: a case–case–control study

ObjectivesThe aim was to determine the characteristics of patients who developed Cutibacterium acnes spinal implant-associated infection (SIAI) and the associated risk factors.MethodsWe conducted two parallel case–control studies comparing 59 patients with SIAI caused by C. acnes (cases 1) and 93 patients with SIAI caused by other microorganisms (cases 2) diagnosed during 2010–2015 with 302 controls who underwent spinal instrumentation without subsequent infection.ResultsLate-onset infections (median time to diagnosis, 843 days versus 23 days; p < 0.001) were more common in cases 1 than in cases 2. However, 20/59 (34%) of cases 1 occurred within the first 3 months after the index surgery. In addition, cases 1 were less likely to have fever (27%, 16/59 versus 58%, 54/93; p 0.001) or wound inflammation (39%, 23/59 versus 72%, 67/93; p < 0.001). Moreover, 24/59 (40%) of cases 1 presented with polymicrobial infections, and staphylococcal pathogens accounted for 22/24 (92%) of the co-infections. By comparing and contrasting the two multivariate risk models (cases 1 versus controls and cases 2 versus controls), the following factors associated with C. acnes SIAI development were identified: age <54 years (adjusted odds ratio (aOR) 2.43, 95% confidence interval (CI) 1.09–5.58, p 0.03), a body mass index <22 kg/m² (aOR 2.47, 95% CI 1.17–5.29, p 0.02), and thoracic instrumentation (aOR 16.1, 95% CI 7.57–37.0, p < 0.001).ConclusionsFuture therapeutic and prophylactic studies on C. acnes SIAI should focus on young, thin patients who undergo spinal instrumentation procedures involving the thoracic spine.     

Risk factors for candidaemia in hospitalized patients with liver cirrhosis: a multicentre case–control–control study

ObjectivesThe aim of this study was to evaluate the risk factors for candidaemia in patients with liver cirrhosis.MethodsThis was a case–control–control (1:2:2) study performed in four Italian tertiary centres from 2006 to 2015. Cases were patients with liver cirrhosis developing candidaemia. For every case of candidaemia we enrolled two additional patients undergoing blood cultures for suspected infection yielding isolation of a bacterial pathogen (control A) and two additional patients undergoing blood cultures for suspected infection yielding negative results (control B). Patients were matched according to age, sex and model for end stage liver disease at hospital admission.ResultsDuring the study period 90 cases, 180 controls A and 180 controls B were included. At multivariate analysis assessed by means of multinomial conditional regression models, factors independently associated with candidaemia were previous (<30 days) acute-on-chronic liver failure (relative risk ratio (RRR) 2.22 (95% confidence interval (CI) 1.09–4.54), p = 0.046), previous(<30 days) gastrointestinal endoscopy (RRR 2.38 (95% CI 1.19–4.78) p = 0.014), previous(<30 days) antibiotic treatment for at least 7 days (RRR 2.74 (95% CI 1.00–7.48), p = 0.049), presence of central venous catheter (RRR 2.77 (95% CI 1.26–6.09, p = 0.011), total parenteral nutrition (RRR 3.90 (95% CI 1.62–9.40), p = 0.002) at infection onset and length of in-hospital stay >15 days (RRR 4.63 (95% CI 2.11–10.18), p <0.001] Conversely, rifaximin treatment was associated with lower rate of candidaemia (RRR 0.38 (95% CI 0.19–0.77), p = 0.007). Multivariable analysis for 30-day mortality showed that patients with isolation of Candida spp. from blood cultures had worse outcome when compared with controls even though the difference did not reach a statistical significance (hazard ratio 1.64 (95% 0.97–2.75) p = 0.06).ConclusionsWe identified previous antibiotic use, gastrointestinal endoscopy or acute-on-chronic liver failure and presence of central venous catheter especially for parenteral nutrition as independent factors associated with candidaemia. Surprisingly, chronic rifaximin use was a protective factor.     

Polymicrobial pneumococcal bacteraemia: a case–control study

European Journal of Clinical Microbiology & Infectious Diseases - Polymicrobial bacteraemia involving Streptococcus pneumoniae and other bacteria (e.g. Escherichia coli, Staphylococcus aureus,...     

Risk factors for Clostridium difficile toxin-positive diarrhea: a population-based prospective case–control study

Increased incidence and severity of Clostridium difficile infections (CDIs) is of major concern. However, by minimizing known risk factors, the incidence can be decreased. The aim of this investigation was to calculate the incidence and assess risk factors for CDI in our population. A 1-year prospective population-based nationwide study in Iceland of CDIs was carried out. For risk factor evaluation, each case was matched with two age- and sex-matched controls that tested negative for C. difficile toxin. A total of 128 CDIs were identified. The crude incidence was 54 cases annually per 100,000 population >18?years of age. Incidence increased exponentially with older age (319 per 100,000 population >86?years of age). Community-acquired origin was 27?%. Independent risk factors included: dicloxacillin (odds ratio [OR]: 7.55, 95?% confidence interval [CI]: 1.89-30.1), clindamycin (OR: 6.09, 95?% CI: 2.23-16.61), ceftriaxone (OR: 4.28, 95?% CI: 1.59-11.49), living in a retirement home (OR: 3.9, 95?% CI: 1.69-9.16), recent hospital stay (OR: 2.3, 95?% CI: 1.37-3.87). Proton pump inhibitors (PPIs) were used by 60/111 (54?%) versus 91/222 (41?%) (p?=?0.026) and ciprofloxacin 19/111 (17?%) versus 19/222 (9?%) (p?=?0.027) for cases and controls, respectively. In all, 75?% of primary CDIs treated with metronidazole recovered from one course of treatment. CDI was mostly found among elderly patients. The most commonly identified risk factors were broad-spectrum antibiotics and recent contact with health care institutions. PPI use was significantly more prevalent among CDI patients.     

Risk factors for MRSA infection in companion animals: Results from a case–control study within Germany

Increasing numbers of companion animals suffering from infections with methicillin-resistant Staphylococcus aureus (MRSA) have been reported in the recent past. These infections are of particular concern because of the limited treatment options for MRSA and their transferability to humans. Since MRSA lineages isolated from infected companion animals often mirror typical human epidemic strains circulating in the same region, successful strategies to combat MRSA need strong and coordinated efforts from both, the human and the veterinary field according to the “One Health” concept. Hence, to identify potential risk factors related to MRSA infections in dogs, cats and horses, a case–control study was conducted, including data on 106 MRSA-infected animal patients as cases and 102 MSSA-infected animals as controls, originating from 155 different veterinary settings within Germany. Demographic data on animal patients, patient history and administration of antibiotics as well as practice/clinic specific parameters were assessed as putative risk factors. Multivariable logistic regression identified the following variables as risk factors for MRSA infection compared to MSSA infection: number of employees working at the veterinary setting (n > 10; p < 0.001), antibiotic treatment prior to sampling (systemic: p = 0.002; local: p = 0.049, both: p = 0.011) and surgical site infection (p < 0.001). Spa typing revealed predominantly clonal complexes well-known for hospital-associated lineages spreading in human health-care settings in Germany (CC5 and CC22) for isolates of dog and cat origin. CC398-MRSA dominated among equine isolates, a CC that was described as a nosocomial pathogen in equine clinical settings before.     

Factors associated with local invasion in infective endocarditis: a nested case–control study

ObjectiveA substantial proportion of infective endocarditis (IE) cases are complicated by local invasion. The purpose of this study was to identify patient and disease characteristics associated with local invasion in surgically treated IE patients.MethodsThis was a nested case–control study. All episodes of IE for patients admitted to Cleveland Clinic from 1 January 2013 to 30 June 2016 were identified from the Cleveland Clinic IE Registry. Patients ≥18 years of age who underwent surgery for IE were included. Among these, cases were those with local invasion, controls were those without. Local invasion, defined as periannular extension, paravalvular abscess, intracardiac fistula or pseudoaneurysm, was ascertained from the surgical operative note. Associations of selected factors with local invasion were examined in a multivariable logistic regression model.ResultsAmong 511 patients who met inclusion criteria, 215 had local invasion. Mean age was 56 years; 369 were male. Overall 345 (68%) had aortic valve, 228 (45%) mitral valve, and 66 (13%) tricuspid or pulmonic valve involvement. Aortic valve involvement (OR 6.23, 95% CI 3.55–11.44), bioprosthetic valve (OR 3.88, 95% CI 2.36–6.44), significant paravalvular leak (OR 3.80, 95% CI 1.60–9.89), new atrioventricular nodal block (OR 3.77, 95% CI 1.87–7.90), infection with streptococci other than viridans group streptococci (OR 7.54, 95% CI 2.42–24.87) and presence of central nervous system emboli (OR 1.85, 95% CI 1.13–3.04) were associated with local invasion.DiscussionIntracardiac and microorganism factors, but not comorbid conditions, are associated with local invasion in IE.     

Risk factors for community-onset bloodstream infection with extended-spectrum β-lactamase-producing Enterobacteriaceae: national population-based case–control study

ObjectivesThe aim was to investigate risk factors for community-onset bloodstream infections with extended-spectrum β-lactamase-producing Enterobacteriaceae (EPE BSI).MethodsIt is mandatory to report EPE BSI to a national register at the Public Health Agency of Sweden. Using this register, we performed a population-based case–control study from 2007 to 2012 of 945 cases and 9390 controls. Exposure data on comorbidity, hospitalization, in- and outpatient antibiotic consumption and socio-economic status were collected from hospital and health registers.ResultsThe overall incidence of EPE BSI was 1.7 per 100 000 person-years. The 30-day mortality was 11.3%. Urological disorders inferred the highest EPE BSI risk, adjusted odds ratio (aOR) 4.32 (95% Confidence Interval (CI) 3.41–5.47), followed by immunological disorders, aOR 3.54 (CI 2.01–6.23), haematological malignancy, aOR 2.77 (CI 1.57–4.87), solid tumours, aOR 2.28 (1.76–2.94) and diabetes, aOR 2.03 (1.58–2.61). Consumption of fluoroquinolones or mostly non-EPE-active antibiotics with selective Gram-negative spectrum of activity within the previous 3 months was associated with EPE BSI, aORs 5.52 (CI 2.8–11.0) and 3.8, CI 1.9–7.7) respectively. There was a dose–response relationship in EPE BSI risk with increasing number of consecutive regimens. Antibiotic consumption >3 months before EPE BSI was not associated with increased risk. Higher age, malignancies and education ≤12 years (aORs >2) were associated with increased 30-day mortality.ConclusionsTargeted interventions should be directed towards improving care for patients with immunosuppression, urological disorders and subjects with lower socio-economic status. Antibiotic stewardship should focus on reduction of fluoroquinolones.     

Diet as a risk factor for antimicrobial resistance in community-acquired urinary tract infections in a middle-aged and elderly population: a case–control study

ObjectivesThere is an ongoing debate as to what extent antimicrobial resistance (AMR) can be transmitted from animals to humans via the consumption of animal products. Because epidemiological data on the role of diet in AMR in humans are lacking, we investigated this association between diet and AMR for different antimicrobial drugs in Escherichia coli (E. coli) in urinary tract infections (UTIs).MethodsSusceptibility of E. coli in urinary cultures and information on diet (with food frequency questionnaires) were obtained from participants of the Rotterdam study, a population-based prospective cohort study. The association between intake of several food groups (meat, seafood, eggs, dairy products, crops) and resistance of E. coli to several antimicrobial drugs (amoxicillin, amoxicillin-clavulanic acid, trimethoprim, sulfamethoxazole-trimethoprim, first-generation cephalosporins, cefotaxime, nitrofurantoin, norfloxacin) was studied.ResultsUrinary cultures with E. coli were obtained from 612 individuals, of whom 481 (78.6%) were women. Resistance rates varied from 246/611 (40.3%) for amoxicillin and 167/612 (27.3%) for trimethoprim to only 29/612 (4.7%) for nitrofurantoin and 16/462 (3.5%) for cefotaxime. A higher intake of chicken was associated with cefotaxime resistance (OR 2.18; 95% CI 1.05–4.51 per tertile increase); a higher intake of pork was associated with norfloxacin resistance (OR 1.42; 95% CI 1.04–1.95 per quartile increase). In contrast, a higher intake of cheese was associated with lower AMR to amoxicillin (OR 0.84; 95% CI 0.72–0.99 per quartile increase) and amoxicillin-clavulanic acid (OR 0.67; 95% CI 0.53–0.86 per quartile increase).ConclusionsThese findings support the hypothesis that diet may play a role in the AMR of E. coli in UTIs.     

Bacteraemic urinary tract infections may mimic respiratory infections: a nested case–control study

Daily practice suggests that respiratory signs may be observed in bacteraemic urinary infections (BUI). Our objective was to search for an association between the presence of respiratory symptoms and the bacteraemic nature of urinary tract infections (UTI). A nested case–control study was carried out based on our computerised dashboard from January 2011 to June 2015. Cases were defined as patients with a BUI due to Enterobacteriaceae species, identified in blood and urine cultures. Controls had fever and a positive urinary sample but sterile blood cultures (NBUI) and a final diagnosis of urinary infection. Patients from the BUI group were 1:1 matched to the NBUI group according to four parameters: age, gender, cardiovascular and pulmonary comorbid conditions. Subjects with cognitive impairment limiting clinical accuracy and those with healthcare-associated infections were excluded. We compared systematically recorded respiratory and urinary symptoms between groups: signs on auscultation, dyspnoea, chest pain, cough and sputum, dysuria with burning, pollakiuria, flank or costovertebral angle tenderness and ischuria. One hundred BUI were compared to 100 NBUI, both groups exhibiting a similar rate for all considered comorbid conditions. In the BUI group, 58 % showed at least one respiratory sign vs. 20 % in the NBUI group, p?<?0.001, while urinary signs were less frequent: 54 % vs. 71 %, p?=?0.013. In the multivariate analysis, BUI was associated with the presence of abnormal pulmonary auscultation [adjusted odds ratio (AOR), 5.91; p?<?0.001] and a trend towards less urinary symptoms (AOR, 1.58; p?=?0.058). Patients with BUI presented with significantly more respiratory signs, which overshadowed urinary symptoms, compared to those with non-bacteraemic UTI. Such observations impact clinical decision-making.     

Pneumocystis jirovecii pneumonia in renal transplant recipients occurring after discontinuation of prophylaxis: a case–control study

A case–control study was conducted to identify risk factors for Pneumocystis jirovecii pneumonia (PCP) in renal transplant recipients. Eleven cases of PCP were matched with 22 controls. Cases occurred a median of 18 months after transplantation, and none of the recipients was receiving prophylaxis. Univariate analysis showed that graft rejection, duration of steroid use, use of mammalian target of rapamycin (mTOR) inhibitors and lymphocytopenia at the time of prophylaxis discontinuation were risk factors for PCP. In the multivariate model, only graft rejection (OR 8.66, p 0.017) remained significantly associated with PCP. In patients with a history of graft rejection, PCP prophylaxis should be maintained, especially among those with lymphocytopenia.     

Risk of breast cancer in symptomatic women in primary care: a case–control study using electronic records

Background

Breast cancer is the most common cancer in the UK. GPs are encouraged to refer all women whose symptoms may represent cancer, rather than selecting those at highest risk.

Aim

To identify and quantify features of breast cancer in primary care.

Design and setting

A UK case–control study using the Clinical Practice Research Database (CPRD).

Method

Possible features of breast cancer were identified in the year before diagnosis, and odds ratios calculated using conditional logistic regression. Positive predictive values (PPVs) were estimated for consulting women.

Results

A total of 3994 women aged ≥40 years with breast cancer between 2000 and 2009, and 16 873 age-, sex-, and practice-matched controls were studied. Median age at diagnosis was 63 years (interquartile range 55–74 years). Four features were significantly associated with breast cancer: breast lump (odds ratio [OR] 110; 95% confidence interval [CI] = I88 to150), breast pain (OR = 4.2; 95% CI = 3.0 to 6.0), nipple retraction (OR = 26; 95% CI = 10 to 64), nipple discharge (OR = 19; 95% CI = 8.6 to 41): all P-values <0.01. In the year before diagnosis, 1762 (44%) of cases had a breast lump compared with 132 (0.8%) controls. The PPV of breast cancer with a breast lump was 4.8% in women aged 40–49 years, rising to 48% in women aged >70 years. PPVs were lower in women who also reported breast pain.

Conclusion

Generally, the figures support current referral practice. However, the low likelihood of cancer for all the non-lump symptoms means that the current guidance recommends investigation for possible cancer at a more liberal risk threshold than for other cancers. Although supported by patients, this may not meet current NHS criteria for cost–benefit.     

Development of diagnostic prediction tools for bacteraemia caused by third-generation cephalosporin-resistant enterobacteria in suspected bacterial infections: a nested case–control study

ObjectivesCurrent guidelines for the empirical antibiotic treatment predict the presence of third-generation cephalosporin-resistant enterobacterial bacteraemia (3GCR-E-Bac) in case of infection only poorly, thereby increasing unnecessary carbapenem use. We aimed to develop diagnostic scoring systems which can better predict the presence of 3GCR-E-Bac.MethodsA retrospective nested case–control study was performed that included patients ≥18 years of age from eight Dutch hospitals in whom blood cultures were obtained and intravenous antibiotics were initiated. Each patient with 3GCR-E-Bac was matched to four control infection episodes within the same hospital, based on blood-culture date and onset location (community or hospital). Starting from 32 commonly described clinical risk factors at infection onset, selection strategies were used to derive scoring systems for the probability of community- and hospital-onset 3GCR-E-Bac.Results3GCR-E-Bac occurred in 90 of 22 506 (0.4%) community-onset infections and in 82 of 8110 (1.0%) hospital-onset infections, and these cases were matched to 360 community-onset and 328 hospital-onset control episodes. The derived community-onset and hospital-onset scoring systems consisted of six and nine predictors, respectively. With selected score cut-offs, the models identified 3GCR-E-Bac with sensitivity equal to existing guidelines (community-onset: 54.3%; hospital-onset: 81.5%). However, they reduced the proportion of patients classified as at risk for 3GCR-E-Bac (i.e. eligible for empirical carbapenem therapy) with 40% (95%CI 21–56%) and 49% (95%CI 39–58%) in, respectively, community-onset and hospital-onset infections.ConclusionsThese prediction scores for 3GCR-E-Bac, specifically geared towards the initiation of empirical antibiotic treatment, may improve the balance between inappropriate antibiotics and carbapenem overuse.     

Bacteremia with Streptococcus pneumoniae: sepsis and other risk factors for 30-day mortality—a hospital-based cohort study

We conducted a hospital-based cohort study among adult patients with first-time Streptococcus pneumoniae bacteremia (SPB) from 2000 through 2008. Patients were identified in a population-based bacteremia database and followed up for mortality through the Danish Civil Registration System (CRS). The aim of the study was to determine the focal diagnosis of SPB, the severity of sepsis at presentation, demographics and comorbidity characteristics of the patients, and to determine the 30-day mortality rate and factors related to mortality. We identified 481 patients, of which 238 were males. The mean age of the patients was 65?years. The focal diagnosis of the SPB was pneumonia in 381 (79?%) patients, followed in frequency by meningitis in 33 (7?%) patients. Of the 481 patients, 390 (81?%) had community-acquired SPB. Of these, 23 (6?%) did not have sepsis, 132 (34?%) had sepsis, 224 (57?%) had severe sepsis, and 11 (3?%) were in septic shock. Overall, the 30-day mortality was 16?%. Mortality increased with the severity of sepsis. There was no association between the focal diagnosis of SPB or the number of diagnoses and mortality. Nosocomial infection, male sex, increasing age, and increasing comorbidity were all associated with an increased 30-day mortality rate.     

Daptomycin versus vancomycin for osteoarticular infections due to methicillin-resistant Staphylococcus aureus (MRSA): a nested case–control study

Vancomycin is the standard antibiotic for the treatment of methicillin-resistant Staphylococcus aureus (MRSA) infections. While daptomycin is approved for MRSA bacteremia, its effectiveness in osteoarticular infections (OAIs) has not been established. A 1:2 nested case–control study of adult patients with MRSA OAIs admitted to an academic center from 2005 to 2010 was carried out. Clinical outcomes and drug toxicity in patients treated with daptomycin versus vancomycin were compared. Twenty patients with MRSA OAIs treated with daptomycin were matched to 40 patients treated with vancomycin. The median age of the patients was 52 years (range, 25–90), and 40 (67 %) were male. Most patients had osteomyelitis (82 %), predominantly from a contiguous source (87 %). Forty percent were diabetics. Diabetic patients were more likely to receive vancomycin than daptomycin [20 (50 %) vs. 4 (20 %); p?=?0.03]. Vancomycin was more often combined with antibiotics other than daptomycin [22 (55 %) vs. 5 (25 %); p?=?0.03]. The median total antibiotic treatment duration was 48 (daptomycin) vs. 46 days (vancomycin) (p?=?0.5). Ninety percent of daptomycin-treated patients had previously received vancomycin for a median of 14.5 days (range, 2–36). Clinical success rates were similar between daptomycin and vancomycin at 3 months [15 (75 %) vs. 27 (68 %); p?=?0.8] and 6 months [14 (70 %) vs. 23 (58 %); p?=?0.5], even after propensity score-based adjustment for antibiotic assignment. The frequency of adverse events was similar between treatment groups [1 (5 %) vs. 7 (18 %); p?=?0.2]. Daptomycin and vancomycin achieved similar rates of clinical success and drug tolerability. Daptomycin is a reasonable alternative for treating MRSA OAIs, particularly in patients where therapy with vancomycin has not been well tolerated.