Infections in patients with end-stage renal disease. An overview

Younger black patients have a higher risk of infection mortality that is mostly non-dialysis related: A national study of cause-specific mortality among U.S. maintenance dialysis patients

INTRODUCTION

While it has been well documented that in the U.S., black and Hispanic dialysis patients have overall lower risks of death than white dialysis patients, little is known whether their lower risks are observed in cause-specific deaths. Additionally, recent research reported that younger black patients have a higher risk of death, but the source is unclear. Therefore, this study examined cause-specific deaths among US dialysis patients by race/ethnicity and age.

METHODS

This national study included 1,255,640 incident dialysis patients between 1995 and 2010 in the United States Renal Data System. Five cause-specific mortality rates, including cardiovascular (CVD), infection, malignancy, other known causes (miscellaneous), and unknown, were compared across blacks, Hispanics, and whites overall and stratified by age groups.

FINDINGS

After multiple adjustments, Hispanic patients had the lowest risk of mortality for every major cause in almost all ages. Compared with whites, blacks had a lower risk of death from CVD, malignancy and miscellaneous causes in most age groups, but not from infection. In fact, blacks had a higher risk of infection death than whites in ages 18-30 years (HR [95% CI] 1.94 [1.69-2.23]; P < 0.001), 31-40 years (HR 1.51 [1.40-1.63]; P < 0.001) and 41-50 years (HR 1.07 [1.02-1.12]; P = 0.009), which were partially attributed to their higher prevalence of AIDS nephropathy. For each race/ethnicity, more than two-thirds of infection deaths were due to non-dialysis related infections.

DISCUSSION

Hispanics had the lowest risk for each major cause of death. Blacks were less likely to die than whites from most causes, except infection. The previously reported higher overall mortality rate for younger blacks is attributed to their two-fold higher infection mortality, which is mostly non-dialysis related, suggesting a new direction to improve their overall health status. Research is greatly needed to determine social and biological factors that account for the survival gap in dialysis among different racial/ethnic groups.

Isolation Rate and Clinical Significance of Uropathogens in Positive Urine Cultures of Hemodialysis Patients

BACKGROUND

Hemodialysis (HD) patients are known to be vulnerable to infections. However, there are limited data on the urine microbiology spectrum among patients with end-stage renal disease and on the development of antimicrobial resistance of uropathogens in these patients.

MATERIALS AND METHODS

A single-center, retrospective study was conducted to assess the spectrum and antimicrobial resistance profile of microorganisms isolated in urine cultures of HD patients who were hospitalized between September 2008 and August 2015 with an admitting diagnosis of fever, sepsis, or urinary tract infection. Characteristics of patients were recorded, and associations between the aforementioned parameters were assessed with Fisher's exact test.

RESULTS

We included 75 HD patients (33 males, mean age 73.6 ± 16.6 years) with positive urine cultures. Despite urine culture positivity, the urinary tract was the confirmed source of infection in only 31 (41.3%) patients. Among the different pathogens, Escherichia coli was the predominant microorganism. Identification of E. coli as the involved uropathogen was associated neither with a growth of ≥105 CFU/ml, presence of fever, sepsis, urinary catheter use nor with higher antimicrobial resistance. E. coli growth, however, was significantly associated with polycystic kidney disease (P = 0.027). Extended antimicrobial resistance was noted in 29 (38.7%) patients but was associated neither with higher incidence of fever or sepsis nor with urinary catheter use.

CONCLUSIONS

In our series of HD patients with positive urine cultures, the isolation rates of different uropathogens do not seem to differ from the most commonly encountered ones in nondialysis patients although resistance to antimicrobials may be more frequently observed.

Risk Factors and Temporal Trends of Hospital-Acquired Infections (HAIs) Among HIV Positive Patients in Urban New York City Hospitals: 2006 to 2014

BACKGROUND

HIV-infected patients may be at a greater risk of Hospital-Acquired Infections (HAIs) but risks factors for HAIs have not been well described in this population.

OBJECTIVE

The aim of this study was to examine the incidence, temporal trends and risk factors of HAIs among adult HIV positive patients.

METHODS

This was a retrospective cohort study carried out in an academic health system in New York City which included four hospitals over a 9-year period from 2006 to 2014. Simple and multiple logistic regression models were built to determine risk factors associated with site-specific HAIs such as Urinary Tract Infections (UTIs), Pneumonia (PNUs) and Bloodstream Infections (BSIs).

FINDINGS

There were 10,575 HIV positive discharges and 1,328 had HAIs: 697 UTIs, 555 BSIs and 192 PNUs. The incidence rate of HAIs decreased from 19.8 to 15.1 new infections per 1000 persondays between 2006 and 2014 (p value<0.001). In addition to the expected risk factors of urinary catheter use for UTI and central venous line use for BSI, symptomatic HIV and renal failure were significant risk factors for both UTIs (95% CI OR: (1.24, 2.27) and (1.46, 2.11) respectively) and BSIs (95% CIs OR: (2.28, 4.18) and (1.81, 2.71) respectively).

CONCLUSION

HIV-infected patients had similar risk factors for HAIs as HIV-uninfected patients. Further research is required to address how patients' CD4 counts and viral loads affect their susceptibility to HAIs.

Antibiotic resistance patterns of microorganisms isolated from nephrology and kidney transplant wards of a referral academic hospital

OBJECTIVE

Antibiotic use pattern and emergence of resistant bacteria are major concerns in clinical settings. This study aimed to detect common bacteria and their antibiotic sensitivity patterns in nephrology and kidney transplant wards.

METHODS

This 1-year, observational study was performed in the nephrology and kidney transplant wards of Imam Khomeini Hospital Complex, Tehran, Iran. All patients treated with antimicrobial agents for confirmed or suspected infections were included. Their demographic, clinical, and laboratory data (including biological media used for microbial culture, growth organisms, and antibiograms) were collected. Adherence of antimicrobial regimen to standard guidelines was also assessed.

FINDINGS

About half of the patients received antibiotic. The most common infecting bacteria were Escherichia coli followed by Enterococcus sp. and Staphylococcus aureus. E. coli showed high rate of sensitivity to carbapenems and nitrofurantoin and high rate of resistance to co-trimoxazole and ciprofloxacin. Enterococcus sp. in both wards had high rate of resistance to ampicillin and were all sensitive to linezolid. Unlike to the nephrology ward, more than 50% of Enterococcus sp. from kidney transplant ward was resistant to vancomycin. The most common type of S. aureus in this nephrology ward was methicillin-resistant S. aureus (MRSA). Most commonly-prescribed antibiotics were carbapenems followed by vancomycin, ciprofloxacin, and ceftriaxone. Antibiotic regimens were 75% and 83%, 85% and 91%, and 80% and 87% compatible with international guidelines in antibiotic types, dosages, and treatment durations, respectively, in nephrology and kidney transplant wards, respectively.

CONCLUSION

MRSA, fluoroquinolone-resistant E. coli, and vancomycin resistant Enterococcus species are major threats in nephrology and kidney transplant wards. Most commonly-prescribed antibiotics were carbapenems that necessitate providing internal guidelines by the teamwork of clinical pharmacist, infectious disease specialists, and nephrologists to avoid the widespread use of broad-spectrum antibiotics.

Innovations in diabetic foot reconstruction using supermicrosurgery

The treatment of diabetic foot ulceration is complex with multiple factors involved, and it may often lead to limb amputation. Hence, a multidisciplinary approach is warranted to cover the spectrum of treatment for diabetic foot, but in complex wounds, surgical treatment is inevitable. Surgery may involve the decision to preserve the limb by reconstruction or to amputate it. Reconstruction involves preserving the limb with secure coverage. Local flaps usually are able to provide sufficient coverage for small or moderate sized wound, but for larger wounds, soft tissue coverage involves flaps that are distantly located from the wound. Reconstruction of distant flap usually involves microsurgery, and now, further innovative methods such as supermicrosurgery have further given complex wounds a better chance to be reconstructed and limbs salvaged. This article reviews the microsurgery involved in reconstruction and introduces the new method of supermicrosurgery.

Modified laparoscopic technique for fixation of peritoneal dialysis catheter

BACKGROUND

Continuous ambulatory peritoneal dialysis (CAPD) is a treatment for patients with end-stage renal disease (ESRD). Peritoneal dialysis catheters are usually placed using a small laparotomy. This traditional technique is usually safe if well executed, but it cannot be safely performed if the patient has had a previous abdominal operation. A minimally invasive procedure may progress safely by laparoscopic intervention. However, dysfunction of the catheter during a laparoscopic intervention is a common complication related to CAPD. This usually involves intra-abdominal migration of the catheter, even with one intra-abdominal fixation. In an effort to increase catheter survival, we tested a modified laparoscopic technique with two intra-abdominal fixations of a Tenckhoff catheter.

MATERIALS AND METHODS

Forty-one consecutive ESRD patients (mean age, 53.4 y; range, 31 to 84 y) underwent modified laparoscopic Tenckhoff catheter implantation with 2 intra-abdominal fixations between September 2009 and January 2013. The same perioperative protocol and surgical technique were used in all patients. Another 49 ESRD patients who had received laparoscopic Tenckhoff catheter implantation with 1 intra-abdominal fixation performed by the same surgeon were retrospectively recruited for comparison.

RESULTS

The modified laparoscopic procedure with two intra-abdominal fixations of a Tenckhoff catheter was successfully performed in all patients. The mean operating time was 24.3 minutes (range, 15 to 37 min). The mean blood loss was 5.6 mL (range, 5 to 20 mL). Catheter survival was 100% until February 2013. No major perioperative complications were found. A Kaplan-Meier Survival Analysis found no significant difference between the 2 groups in sex, age, operative time, or blood loss. The catheter survival rate was significantly higher in the patients with two intra-abdominal fixations. Most patients were satisfied with the functional results of the Tenckhoff catheter.

CONCLUSIONS

The laparoscopic 2-site fixation technique is an effective and safe procedure but long-term follow-up and more cases are necessary.

Microbial aetiology of healthcare associated pneumonia in Spain: a prospective, multicentre, case-control study

INTRODUCTION

Healthcare-associated pneumonia (HCAP) is actually considered a subgroup of hospital-acquired pneumonia due to the reported high risk of multidrug-resistant pathogens in the USA. Therefore, current American Thoracic Society/Infectious Diseases Society of America guidelines suggest a nosocomial antibiotic treatment for HCAP. Unfortunately, the scientific evidence supporting this is contradictory.

METHODS

We conducted a prospective multicentre case-control study in Spain, comparing clinical presentation, outcomes and microbial aetiology of HCAP and community-acquired pneumonia (CAP) patients matched by age (±10 years), gender and period of admission (±10 weeks).

RESULTS

476 patients (238 cases, 238 controls) were recruited for 2 years from June 2008. HCAP cases showed significantly more comorbidities (including dysphagia), higher frequency of previous antibiotic use in the preceding month, higher pneumonia severity score and worse clinical status (Charslon and Barthel scores). While microbial aetiology did not differ between the two groups (HCAP and CAP: Streptococcus pneumoniae: 51% vs 55%; viruses: 22% vs 12%; Legionella: 4% vs 9%; Gram-negative bacilli: 5% vs 4%; Pseudomonas aeruginosa: 4% vs 1%), HCAP patients showed worse mortality rates (1-month: HCAP, 12%; CAP 5%; 1-year: HCAP, 24%; CAP, 9%), length of hospital stay (9 vs 7 days), 1-month treatment failure (5.5% vs 1.5%) and readmission rate (18% vs 11%) (p<0.05, each).

CONCLUSIONS

Despite a similar clinical presentation, HCAP was more severe due to patients' conditions (comorbidities) and showed worse clinical outcomes. Microbial aetiology of HCAP did not differ from CAP indicating that it is not related to increased mortality and in Spain most HCAP patients do not need nosocomial antibiotic coverage.

Retrospective study of microorganisms associated with vascular access infections in hemodialysis patients

OBJECTIVE

The aim of this study was to assess microorganisms associated with vascular access-associated infections (VAIs) in hemodialysis patients, with respect to possible origin from the mouth.

STUDY DESIGN

A retrospective and comparative analysis of the microbes associated with VAI in hemodialysis patients treated during a 10-year period was performed with the Human Oral Microbiome Database (HOMD).

RESULTS

Of 218 patient records identified, 65 patients collectively experienced 115 VAI episodes. The most common microorganisms involved were Staphylococcus aureus (49.6% of infections), Staphylococcus epidermidis (10.4%), Serratia marcescens (10.4%), Pseudomonas aeruginosa (9.6%), and Enterococcus faecalis/fecum (8.7%). None of these was found in ≥1% of HOMD clone libraries, indicating that they very rarely colonize the teeth or plaque.

CONCLUSIONS

Most VAIs were associated with microorganisms more likely to originate from other body sites than from the oral cavity. The risk of a VAI being caused by microorganisms originating from the oral cavity is very small.

Does health care associated pneumonia really exist?

The most recent ATS guidelines for nosocomial pneumonia of 2005 describe a new clinical category of patients, Health Care-Associated Pneumonia which includes a number of very heterogeneous conditions possibly associated with a high risk of multi-drug resistant (MDR) infections and of mortality. This paper aims at reviewing the current literature on HCAP and examines the controversial issues of HCAP etiology and outcomes, underlining the need of a profound revision of the HCAP concept in the face of the poor and contrasting scientific evidence supporting its basis.

An algorithm for limb salvage for diabetic foot ulcers

The treatment of diabetic foot ulceration is complex with multiple considerations often leading to limb amputation. This article presents the usefulness of a multidisciplinary approach along with an algorithm to manage and salvage diabetic foot ulcers from amputation. This algorithm is a step-by-step guide to manage the diabetic foot ulcer and can help one in the selection of patients for limb salvage reconstruction.

Possible application of hyperbaric oxygen technology in the management of urogenital and renal diseases

The purpose of this report is to explore possible therapeutic use of hyperbaric oxygen (HBO(2)) technology on renal and urogenital diseases. HBO(2) reduces inflammation, immunity and inflammatory cytokines, stimulates wound repair and angioneogenesis, maintains tissue oxygenation, increases antioxidant enzymes and heals tissue hypoxia and radionecrosis. A literature review of peer-reviewed articles that address HBO(2), genitourological diseases, renal disease, and dialysis was performed. The paper reviews complications of renal diseases, dialysis, clinical applications of HBO(2), and effect of HBO(2) on renal and urogenital diseases. HBO(2) was used successfully to treat calcific uraemic arteriolopathy, and in many cases of acute renal failure. This technique is particularly useful in the treatment of intractable haemorrhagic cystitis secondary to pelvic radiation therapy and Fournier's gangrene. Clearly HBO(2) might play a role in the management of urogenital diseases, urinary bladder dysfunction and diseases, testicular pathology, renal diseases, and post-traumatic ischaemic injury and/or impaired wound healing and infections. The possible role of HBO(2) for autoimmune diseases, uraemic osteodystrophy or neuropathy due to chronic renal diseases is discussed. The clinical application of this technology is expanding and the various biological influences of HBO(2) encourage testing its possible benefit in renal and urological diseases.

Wound complications

This article discusses postoperative wound complications in detail, including host factors that predispose the patient to nonhealing, technical factors in surgery that can reduce the likelihood of infection and dehiscence, and recommendations for postoperative management that can prevent wound healing problems. This discussion includes the treatment of wound complications, ranging from local wound care to various wound coverage options.

Fever of unknown origin in a hemodialysis patient with a failed allograft

Fever of unknown origin (FUO) in hemodialysis (HD) patients represents a diagnostic challenge because differential diagnosis includes diverse etiologies. Causes of FUO in the general population can be classified into 3 diagnostic categories: infections, tumors, and noninfectious inflammatory diseases. Also, chronic HD patients may have additional problems such as infections, the risk for which may be increased by the immunosuppression associated with uremia, vascular access-related infections, and nosocomial infections. Moreover, patients with chronically failed kidney transplants can have low-grade fever and abdominal pain, and if inflammation of the allograft is severe enough, it may result in a spontaneous rupture. Hence, it is important to rapidly recognize, diagnose, and manage these complications. In the present study, we report a case of FUO in an HD patient with a failed graft and discuss clinical approach and management of these patients.

Care of the end-stage renal disease patient on dialysis in the ED

End-stage renal disease is a major public health problem. In the United States, more than 350,000 patients are being treated with either hemodialysis or continuous ambulatory peritoneal dialysis. Given the high burden of comorbidities in these patients, it is imperative that emergency physicians be aware of the complexities of caring for acute illnesses in this population. This article reviews the common medical problems that bring patients with end-stage renal disease to the emergency department, and their evaluation and management.

Free Tissue Transfer in Patients with Renal Disease

Several authors have cited renal disease as a risk factor for free flap failure. The authors performed a retrospective analysis of all patients who underwent free tissue transfer with concomitant renal disease, including acute renal failure, end-stage renal disease, chronic renal insufficiency, and functional kidney transplants, to determine what effect renal disease has on flap survival and overall reconstructive outcome. More than 1053 free flaps were examined. Renal disease was identified in 32 patients who underwent 33 free tissue transfers. Average patient age was 57 years (range, 36 to 80 years). Twelve patients (38 percent) were on chronic dialysis (end-stage renal disease), 18 patients (56 percent) had chronic renal insufficiency, and three patients (9 percent) had the diagnosis of acute renal failure at the time of surgery. Three patients in the chronic renal insufficiency group had a functioning renal transplant. Average follow-up was 16 months. Immediate postoperative complications occurred in 14 patients (42 percent of the 33 flaps). Overall perioperative mortality was 3 percent. Within the first 30 days there were two cases (6 percent) of primary flap failure; an additional four legs were lost as the result of complications related to their bypass grafts. There were no primary flap failures after 30 days; however, within the first year after surgery an additional seven limbs were lost as the result of progressive ischemia or infection, and an additional three patients died. This resulted in a 52 percent incidence of major morbidity or mortality during the first year and a 55 percent reconstructive success rate in survivors at 1 year. No significant difference was seen in postoperative morbidity or mortality when comparing the end-stage renal disease group to the chronic renal insufficiency group; however, patients with renal disease and diabetes tended to have poorer outcomes. Renal disease, especially renal disease associated with diabetes and peripheral vascular disease, can be a strong indicator of possible reconstructive failure. The surgeon and patient should be aware of the medical and surgical complications associated with this procedure at the outset.

Pyocystis in patients on chronic dialysis. A potentially misdiagnosed syndrome

Pyocystis is an important complication of non-functioning urinary bladder, which often poses diagnostic difficulties. We present a case of pyocystis in a patient on chronic hemodialysis who was anuric for one year. The patient was initially diagnosed with diverticulitis. An abdominal C-T scan suggested the diagnosis of pyocystis, which was confirmed by bladder catheterization. The patient was treated with bladder drainage and a prolonged antibiotic course, followed by intermittent saline washing of the bladder.

Seroprevalence of antibodies to legionella pneumophila in hemodialysis patients

Patients with chronic renal failure are at increased risk for infections because of impaired cellular immunity. This study was designed to determine the prevalence of antibodies to Legionella pneumophila serogroups 1 to 6 and to evaluate the possible risk factors for Legionnaires' disease in hemodialysis patients. Serum samples to be screened for antibodies against L pneumophila and risk factor data were collected from 252 hemodialysis patients. The overall prevalence of L pneumophila antibodies in hemodialysis patients was found to be 5.16% There was no statistically significant difference between L pneumophila seropositivity and potential risk factors. Further studies are needed to determine possible risk factors for Legionnaires' disease in hemodialysis patients.

Antimicrobial-resistant, Gram-positive bacteria among patients undergoing chronic hemodialysis

Numerous antimicrobial-resistant pathogens (ARPs) have emerged among patients who undergo chronic hemodialysis (CHD), including vancomycin-resistant enterococci, vancomycin-resistant coagulase-negative staphylococci, Staphylococcus aureus with reduced susceptibility to vancomycin, and linezolid-resistant S. aureus. In June 2002, the first isolate of vancomycin-resistant S. aureus (minimum inhibitory concentration of vancomycin, > or =32 microg/mL) was isolated in the United States from a patient who required CHD. Frequent administration of antibiotics and repeated exposure to settings conducive to cross-transmission contribute to a patient population at considerable risk of harboring ARPs. Dissemination of ARPs among patients who are undergoing CHD is facilitated by the requirement for regular hemodialysis in a closed setting in which health care workers provide concurrent care to multiple patients. Frequent hospitalizations in this patient population further contribute to acquisition of ARPs and to the spread of ARPs to other hospitalized patients. The epidemiology of antimicrobial-resistant, gram-positive pathogens in patients undergoing CHD is reviewed, and recommendations for limiting further dissemination are provided.