Central nervous system infections among individuals with and without end-stage renal disease

Risks of central nervous system infections and related mortality in patients undergoing dialysis

INTRODUCTION

This study aimed to investigate the risks of central nervous system (CNS) infections and related mortality in patients with end-stage renal disease (ESRD) undergoing dialysis.

METHODS

Incident dialysis patients were identified from 2000 to 2013. The risks of CNS infection and related mortality were analyzed.

RESULTS

The adjusted hazard ratio (HR) of CNS infection in the ESRD group compared with the control group was 3.46 (95% confidence interval [CI] 2.75-4.35). The adjusted odds ratio (OR) of 90-day mortality following CNS infections in the ESRD group in comparison with the control group was 5.99 (95% CI 2.78-12.9). The adjusted HR of overall CNS infection for the peritoneal dialysis (PD) group in comparison with the hemodialysis (HD) group was 1.07 (95% CI 0.63-1.82). Influenza vaccination was associated with a lower risks of CNS infection in dialysis patients (adjusted HR: 0.38, 95% CI 0.30-0.48). The adjusted OR of 90-day mortality following CNS infection for the PD group in comparison with the HD group was 1.01 (95% CI 0.55-1.87).

CONCLUSIONS

The risks of CNS infections and related mortality were remarkably high in dialysis patients with no significant difference between patients with ESRD under HD and PD treatment.

Risk and outcome of pyelonephritis among renal transplant recipients

Background

Urinary tract infection is the most common infectious disease requiring hospitalisation following renal transplantation. However, the risk and outcome of post-transplant pyelonephritis remains unclear.

Methods

This population-based cohort study was conducted from 1 January 1990 to 31 December 2009. Each member of a Danish population-based, nationwide cohort of first-time renal transplant recipients was matched by age and gender with up to 19 population controls. Information on hospital discharge diagnosis, emigration, and mortality was obtained from nationwide administrative databases. Individuals were observed from the date of first renal transplantation and until graft loss, emigration, or death. Risk factors were assessed by Poisson regression.

Results

The incidence rate (IR) of first-time hospitalisation for pyelonephritis was 18.5 (95 % confidence interval [CI]: 16.4–20.9) per 1,000 person-years of follow-up (PYFU) among renal transplant recipients (N = 2,656) and 0.26 (CI: 0.21–0.31) per 1,000 PYFU among population controls (N = 49,226) yielding an incidence rate-ratio (IRR) of 72.0 (95 % CI: 57.8–89.7). Among renal transplant recipients, the risk of pyelonephritis decreased during the entire study period and was lowest in 2005–09 (IRR = 0.46, CI: 0.31–0.68). The highest risk of pyelonephritis was observed within the first six months post-transplantation (IR = 69.9 per 1,000 PYFU; CI: 56.4–86.7). Other risk factors for post-transplant pyelonephritis included female gender, high Charlson comorbidity index score, HLA-DR mismatch, cause of renal failure, and calendar period. Interestingly, we found that the combined risk of graft loss and death was 45 %, (CI: 19–77 %) higher in renal transplant recipients following post-transplant pyelonephritis compared to those who had no admission due to pyelonephritis.

Conclusions

The risk of first-time hospitalisation for pyelonephritis among renal transplant recipients is high. Further, post-transplant pyelonephritis was associated with excess risk of graft loss and death; this indicates that strategies aimed at reducing upper urinary tract infections are likely to enhance renal graft survival.

Increased risk of hydrocephalus in long-term dialysis patients

BACKGROUND

The risk of hydrocephalus in end-stage renal disease (ESRD) patients on dialysis has not been studied in depth.

METHODS

Using Taiwan National Health Insurance claims data, we identified 29 684 incident ESRD patients from 2000 to 2010, including 10 030 peritoneal dialysis (PD) patients and 19 654 hemodialysis (HD) patients. The control cohort consisted of 118 736 people randomly selected from those without kidney disease, frequency matched with ESRD patients by age, sex and index year. We also established propensity score-matched cohorts with 10 014 PD and 10 014 HD patients. The incidence rates and hazard ratios (HRs) of hydrocephalus were calculated until the end of 2011.

RESULTS

Incidence rates of hydrocephalus were greater in HD and PD patients than in controls (8.44 and 11.0 versus 4.11 per 10 000 person-years, respectively), with an adjusted HR of 1.86 [95% confidence interval (CI) 1.43-2.41] for all ESRD patients compared with controls. A higher proportion of hydrocephalus patients underwent surgical bypass to relieve hydrocephalus in ESRD patients than controls, 40.7% (46/113) versus 24.5% (67/273), with an adjusted odds ratio of 2.11 (95% CI 1.33-3.36). Compared with controls, the adjusted HRs of communicating hydrocephalus for HD and PD patients were 1.77 (95% CI 1.22-2.55) and 2.51 (95% CI 1.61-3.89), respectively. The propensity score-matched analysis showed an HR of 0.72 (95% CI 0.42-1.23) for hydrocephalus in HD patients compared with PD patients.

CONCLUSIONS

Patients with ESRD are at an increased risk of hydrocephalus. The risk difference between HD and PD patients is not significant.

Pneumocystis jirovecii pneumonia in patients with end-stage renal disease: a comparison with the general population

BACKGROUND

Data on occurrence and risk factors for pneumocystis pneumonia (PCP) in patients with end-stage renal disease (ESRD) are sparse.

METHODS

This was a nationwide population-based study assessing occurrence and risk factors for PCP among patients with ESRD and population controls over a 21-year period (1/1 1990 to 31/12 2010). Using Danish registry data, first-time diagnoses of PCP were identified.

RESULTS

We identified 13 296 adult patients with ESRD and 244 255 controls, yielding 63 560 and 2 223 660 person-years of follow-up (PYFU), respectively. Fifty-eight first-time diagnoses of PCP were recorded in the ESRD group. Forty-six episodes occurred among renal transplant recipients (RTx) and 12 among haemodialysis patients (HD), yielding incidence rates of 181 (136-242) and 43.1 (24.5-75.9) per 100 000 PYFU. Compared to population controls, we found incidence rate-ratios of 125.9 (78.4-204) among RTx and 29.9 (14.1-59.7) among HD patients. Risk factors for PCP in RTx were age 50-65 years, age > 65 years, diabetes, polycystic kidney disease and hypertensive kidney disease/nephrosclerosis with an IRR of 2.22 (1.14-4.31), 3.12 (1.35-7.21), 3.44 (1.16-10.2), 4.25 (1.55-11.7) and 3.87 (1.49-10.0), respectively, and more than 36 months of dialysis before transplantation with an IRR of 1.99 (1.03-3.84). Among RTx the risk of PCP was highest during the first 6 months post-transplantation and increased from the beginning (IR1990-94 = 111 (46.3-267) per 100 000 PYFU) towards the end of the study period (IR2005-10 = 299 (203-439)).

CONCLUSION

The PCP risk is substantial in RTx within the first 6 months of transplantation, emphasizing the potential benefit of prophylactic treatment in the early post-transplant period. Importantly, we identified subgroups within the RTx group that require more attention.