Incidence and mortality of brain abscess in Denmark: a nationwide population-based study.

OBJECTIVES: To examine the incidence and mortality of brain abscesses. METHODS: We accessed nationwide population-based medical registries to obtain data for patients with first-time brain abscesses in Denmark from 1982 through 2016. Annual age- and sex-standardized incidence rates with 95% confidence intervals were calculated and compared by direct standardization. We used Cox regression to compute mortality rate ratios adjusted for age and year groups, sex and Charlson comorbidity index score. RESULTS: We identified 1384 patients (37% female). The overall standardized incidence rate of brain abscess was 0.76 per 100 000 person-years (95% confidence interval 0.70-0.81). The incidence rates gradually increased from 0.60 during 1982-88 to 0.90 per 100 000 person-years during 2010-16, yielding an incidence rate ratio of 1.50 (95% confidence interval 1.26-1.79). This increase in incidence was most pronounced in the proportions of brain abscess patients >40 years of age and those with immuno-compromise. The 1-year mortality declined from 29% during 1982-88 to 20% during 2010-16, yielding an adjusted mortality rate ratio of 0.44 (95% confidence interval 0.31-0.63). Risk factors for death were advanced age, Charlson comorbidity index >0, immuno-compromised status and congenital heart disease. CONCLUSIONS: The incidence of brain abscess in Denmark is low but increasing, especially in the elderly, along with an increasing proportion of brain abscess patients with immuno-compromise. The prognosis has improved during the last decades, but mortality remains high. Risk factors for death in our study were advanced age, presence of comorbidity, immuno-compromised status and congenital heart disease.

Early versus late diagnosis in community-acquired bacterial meningitis: a retrospective cohort study.

OBJECTIVES: To examine clinical characteristics and outcome of patients with late diagnosis of community-acquired bacterial meningitis (CABM). METHODS: We conducted a chart review of all adults with proven CABM in three centres in Denmark from 1998 through to 2014. Patients were categorized as early diagnosis of CABM immediately on admission, or late diagnosis if CABM was not listed in referral or admission records and neither lumbar puncture nor antibiotic therapy for meningitis was considered immediately on admission. We used modified Poisson regression analysis to compute adjusted relative risks with 95% CIs for predictors of late diagnosis and in-hospital mortality. RESULTS: A total of 113/358 (32%) patients were categorized as late diagnosis demonstrating a variety of tentative diagnoses of which 81/113 (72%) were non-infectious. We observed several statistically significant baseline differences (p <0.05) in patients with late versus early diagnosis including age >65 years (56/113, 50% versus 67/245, 27%), neck stiffness (35/97, 36% versus 183/234, 78%), concomitant pneumonia (26/113, 23% versus 26/245, 11%), and meningococcal meningitis (6/113, 5% versus 52/245, 21%). These variables remained statistically significant in multivariate analysis. Moreover, late diagnosis was associated with increased in-hospital mortality (41/113, 36% versus 43/245, 18%; adjusted relative risk 1.7, 95% CI 1.2-2.5). CONCLUSIONS: Late diagnosis of CABM was common and patients were admitted with mostly non-infectious diagnoses. Absence of neck stiffness did not rule out CABM and special attention should be given to patients with pneumonia and the elderly. Late diagnosis was associated with incorrect patient management and increased mortality.

Functional status and quality of life after community-acquired bacteraemia: a matched cohort study.

Severe bacterial infections may have a prolonged negative effect on subsequent functional status and health-related quality of life. We studied hospitalized patients for changes in functional status and quality of life within 1 year of community-acquired bacteraemia in comparison to blood-culture-negative controls. In a prospectively conducted matched cohort study at Aalborg University Hospital, north Denmark, during 2011-2014, we included 71 medical inpatients with first-time community-acquired bacteraemia. For each bacteraemia patient, we matched one blood-culture-negative inpatient control on age and gender. Functional status and quality of life before and after hospitalization were assessed by Barthel-20 and EuroQol-5D questionnaires. We computed the 3-month and 1-year risk for any deterioration in Barthel-20 score and EuroQol-5D index score, and for a deterioration of ≥10 points in EuroQol-5D visual analogue scale score, and used regression analyses to assess adjusted risk ratios (RR) with 95% CIs. Compared with controls, bacteraemia was associated with an increased 3-month risk for deterioration in functional status as assessed by Barthel-20 score (14% versus 3% with deterioration, adjusted RR 5.1; 95% CI 1.2-22.3). The difference was less after 1 year (11% versus 7% with deterioration, adjusted RR 1.6; 95% CI 0.5-4.5). After 3 months, quality of life had become worse in 37% of bacteraemia patients and 28% of controls by EuroQol-5D index score (adjusted RR 1.3; 95% CI 0.8-2.1), with similar findings after 1 year and by visual analogue scale. In conclusion, community-acquired bacteraemia is associated with increased risk for subsequent deterioration in functional status compared with blood-culture-negative controls, and with a high risk for deterioration in quality of life.

Staphylococcus aureus skin and soft tissue infections in primary healthcare in Denmark: a 12-year population-based study.

A rise in community-onset Staphylococcus aureus infections has been observed in European countries. To ascertain secular trends of S. aureus infections in primary healthcare in Denmark, we conducted this register-based study in the North Denmark region, during the period 1997-2008. We identified all skin and mucosa specimens obtained by general practitioners and all prescriptions for the preferred oral anti-staphylococcal antibiotic, dicloxacillin. Repeat observations within a 12-month period were excluded prior to the calculation of age and gender standardised incidence rates per 100,000 person-years. We included 108,758 specimens, of which 42,778 (39%) yielded S. aureus. The annual incidence rate of specimens doubled during the study period, reaching 2,399 in 2008. The overall rate of S. aureus isolates increased 2-fold to a stable rate at about 850, but for isolates from children and for impetigo specimens, the increase was steeper, with a peak in 2002. A total of 156,462 dicloxacillin prescriptions had been redeemed and the annual prescription rate increased 2.5-fold, peaking at 3,714 in 2007. In conclusion, the annual rates of specimens, S. aureus infections and dicloxacillin prescriptions more than doubled in primary healthcare during the 12-year study period. A major impetigo epidemic and calls for antibiotic stewardship with increased utilisation of specimens were contributing factors.