Bodh R. Panhotra

Enhancing the survival of tunneled haemodialysis catheters using an antibiotic lock in the elderly: A randomised, double-blind clinical trial

Background:  Tunneled‐cuffed catheters (TCC) are often used among the elderly to commence and carry out haemodialysis (HD). Complications like infection and thrombosis frequently reduce the lifespan of TCC. The role of an antibiotic heparin ‘lock’ in the prevention of thrombotic and infectious complications and enhancement of TCC survival in the elderly has not been investigated previously.

The Impact of Nurse Understaffing on the Transmission of Hepatitis C Virus in a Hospital-Based Hemodialysis Unit

Objective: To determine the impact of nurse understaffing on the transmission of hepatitis C virus (HCV) infection in a large hospital-based hemodialysis (HD) unit with a high HCV prevalence. Subjects and Methods: The records of 198 patients (107 males and 91 females) with end-stage renal disease enrolled on long-term HD at King Fahad Hospital and Tertiary Care Center, Hofuf, Saudi Arabia, from August 1995 to August 2000, were retrospectively reviewed. The patients were assigned to HD groups of varying patient-to-nurse (P/N) ratios: group I, 2:1; group II, 3:1, and group III, 4:1. HCV prevalence, seroconversion rates, history of blood transfusion and dialysis age (time span since the initiation of the HD treatment) were recorded and compared. Results: The overall HCV prevalence and seroconversion rate per year were 43.4 and 8.6%, respectively. Group I had the lowest HCV prevalence and annual seroconversion rate (26.8%; 5.3%), followed by group II (43.6%; 8.7%); group III had the highest HCV prevalence and seroconversion rate (71.8%; 14.4%). Anti-HCV positivity was associated with a higher dialysis age. Conclusion: The finding that the patients in the groups with the relatively higher P/N ratio had the significantly higher HCV prevalence and seroconversion rates per year indicates that understaffing is likely to play a major role in the transmission of HCV in HD units, and we suggest that improved staffing may be helpful in reducing the HCV transmission in such dialysis units.

Sudden irreversible sensory-neural hearing loss in a patient with diabetes receiving amikacin as an antibiotic-heparin lock.

Gram‐negative septicemia due to central venous catheter‐related infection is a leading cause of mortality and morbidity among patients who undergo hemodialysis. Antibiotic‐heparin locks are valuable for preserving access sites and lowering the cost and inconvenience associated with central venous catheter replacement and surgical interventions. The optimal duration of use of an antibiotic‐heparin lock is unknown. Prolonged use of an amikacin‐heparin lock may lead to severe irreversible sensory‐neural hearing loss. Patients at risk for this complication should be monitored for its emergence to facilitate early detection. A 43‐year‐old man with diabetic end‐stage renal disease received hemodialysis through a permanent catheter. After 16 weeks of using an amikacin‐heparin lock, he suddenly developed sensory‐neural hearing loss of 40 dB, which affected high frequencies. His condition progressed relentlessly within 1 week despite immediate discontinuation of the amikacin‐heparin lock. The patient developed severe irreversible hearing loss below 80 dB for both high and low frequencies.

THE IMPACT OF NASAL CARRIAGE OF METHICILLIN-RESISTANT AND METHICILLIN-SUSCEPTIBLE STAPHYLOCOCCUS AUREUS (MRSA & MSSA) ON VASCULAR ACCESS-RELATED SEPTICEMIA AMONG PATIENTS WITH TYPE-II DIABETES ON DIALYSIS

Background: Fairly higher nasal carriage rates among type-II diabetics place them at a greater risk of endogenous Staphylococcus aureus linked vascular access-related septicemia (VRS) that is also dependent on the type of vascular access used for hemodialysis (HD). The prevalence of nasal carriage of methicillin susceptible and methicillin-resistant S. aureus (MSSA and MRSA) and its impact on VRS was determined in order to identify most vulnerable group and plan potential prophylactic strategies, accordingly. Methods: Five standardized nasal swab cultures were performed in 208 patients enrolled for long-term HD through July 1996 to July 1999. Persistent nasal carriage was defined by two or more positive cultures for MSSA or MRSA. Peripheral blood cultures were collected on clinical suspicion of septicemia. Results: The prevalence of type-II diabetes of 28.0% with 72.4% of nasal carriage rate and three folds higher S. aureus related VRS (RR-3.19, p<0.0001) than diabetic non-carriers on HD, was observed. Type-II diabetics also had higher MSSA and MRSA nasal carriage rates (53.4% and 19.0%) than non-diabetic nasal carriers (18.6 and 6.0%) yet, carried a comparable (RR-4.0 vs. 4.5) risk of VRS between MSSA and MRSA nasal carriers. Among diabetic type-II S. aureus nasal carriers, central venous catheters (CVCs) carried 35 and 38 times higher collective risk of developing MSSA and MRSA nasal carriage-related VRS respectively than Arterio-venous fistula (AVF). The AVF recorded the lowest risk of developing MSSA and MRSA nasal carriage-related VRS (0.013 and 0.010 episodes/patient-year) in both diabetic type-II MSSA and MRSA nasal carrier groups. Conclusions: Diabetic type-II S. aureus nasal carriers on HD through CVCs make an extremely high-risk group for MSSA and MRSA nasal carriage-related VRS. The incidence of S. aureus nasal carriage-related VRS could reasonably be reduced through a challenging obligation of optimizing AVF prevalence in this high-risk group, while limiting the use of CVCs, at the same time.

Advancing age and the risk of nasal carriage of Staphylococcus aureus among patients on long-term hospital-based hemodialysis

Background Elevated nasal carriage rates of Staphylococcus aureus and ensuing complications among the elderly and in those on long-term hemodialysis (HD) are well recognized. The aim of the present study was to determine the extent to which advancing age is associated with the risk of persistent S. aureus nasal carriage among end-stage renal disease (ESRD) patients on long-term HD. Patients and Methods This prospective study involved 205 ESRD patients enrolled for maintenance HD from July 1997 to July 2000. Persistent nasal carriage was defined by two or more positive cultures for methicillin-susceptible (MSSA) or methicillin-resistant S. aureus (MRSA). Five standardized swabs were taken from the anterior nares of all the patients on long-term HD. S. aureus nasal carriage rates were estimated and compared among ESRD patients of different age groups. Results Overall, a prevalence of 38.05% (78/205) for S. aureus nasal carriage was observed, including 27.3% (56/205) for MSSA and 10.7% (22/205) for MRSA. Patients aged 75 to 84 years had the highest (84.6%, 11/13) prevalence of S. aureus nasal carriage (RR, 7.000, 95% CI, 4.350–11.763, P<0.00001). Those aged 65 to 74 years had the next highest (49.0%, 25/51) nasal carriage rates (RR, 4.083, 95% CI, 2.302–7.658, P<0.0001) while patients aged 15 to 24 years (reference group) had the lowest (12.8%, 1/8) prevalence of nasal carriage. The 75 to 84 year age group also had the highest rates of MSSA (46.2%, 6/13), (RR- 3.833, 95% CI, 2.144–7.234, P<0.0001) and MRSA (38.5 %, 5/13) (RR, 6.333, 95%CI, 2.767–16.198, P<0.0001) nasal carriage compared to the reference group. Conclusions Significantly higher persistent MSSA and MRSA nasal carriage rates among ESRD patients >75 years of age are suggestive of an elevated risk of potentially serious S. aureus- related complications among the very elderly during long-term HD. These findings might be helpful in the identification of elderly HD patients as a high-risk group for S. aureus-linked vascular access-related septicemia (VRS) and to evolve appropriate preventive strategies.

The Vulnerability of Middle‐Aged and Elderly Patients to Hepatitis C Virus Infection in a High‐Prevalence Hospital‐Based Hemodialysis Setting

Objectives: To determine the relationship between advancing age and the risk of acquiring hepatitis C virus (HCV) infection, through evaluation and statistical comparison of seroprevalence and seroconversion rates in different age groups of patients on long‐term hemodialysis (HD).

Prevention of catheter‐related bloodstream infections: An appraisal of developments in designing an infection‐resistant ‘dream dialysis‐catheter’ (Review Article)

SUMMARY:  With the increasing number of elderly, diabetics and debilitated patients being accepted for haemodialysis (HD), the use of central venous catheters (CVCs) as vascular access has become more widespread, with an inevitable inherent risk of catheter‐related bloodstream infections (CRBSI) and ensuing mortality. No reliable plans for the effective management of CRBSI without actually sacrificing vascular access sites are presently available. Therefore, the onus really falls on renal physicians to make effective use of the established supportive guiding principles, practices, policies and programs to prevent CRBSI among HD patients. A huge body of research in polymer industry has aimed at alterations of physical, chemical, biological and immunological properties of CVCs to prevent the bacterial colonization of catheters. Developing an infection‐resistant dialysis catheter has been an elusive dream. This article analyses the current state‐of‐the‐art strategies aimed at preventing CRBSI and also reviews the progress made to date, in the direction of development of a ‘bioactive’ thrombosis and infection‐resistant dialysis catheter.

Emerging nalidixic acid and ciprofloxacin resistance in non-typhoidal Salmonella isolated from patients having acute diarrhoeal disease.

BACKGROUND Non-typhoidal Salmonella are one of the key etiological agents of diarrhoeal disease. The appearance of multiple drug resistance along with resistance to quinolones in this bacterium poses a serious therapeutic problem. We determined the prevalence of nalidixic acid and ciprofloxacin resistance in non-typhoidal Salmonella isolated from faecal samples of patients with acute diarrhoeal disease attending the outpatient and inpatient department of a hospital in Saudi Arabia during the years 1999 to 2002. METHODS Non-typhoidal Salmonella were isolated from faecal samples. Antimicrobial susceptibility was tested by the disc diffusion test. MICs to nalidixic acid and ciprofloxacin were determined by the agar dilution method. RESULTS During the study period, 524 strains of non-typhoidal Salmonella were isolated. Strains belonging to serogroup C1 were the commonest (41.4%) followed by serogroups B and D (15.6% and 14.5%, respectively). Resistance to ampicillin was observed in 22.9% and to trimethoprim/sulfamethoxazole in 18.5% of the strains. Nalidixic acid resistance was encountered in 9.9% and ciprofloxacin resistance in 2.3% of the strains. Resistance to nalidixic acid significantly increased from 0.1% in 1999 to 5.5% in 2002 (P=0.0007) and ciprofloxacin resistance increased significantly from 0.1% in 1999 to 0.9% in 2002 (P=0.0001). MICs to nalidixic acid and ciprofloxacin were determined among 29 nalidixic acid-resistant strains of non-typhoidal Salmonella isolated during 2002. The MIC was >256 microg/mL to nalidixic acid and 8 to 16 microg/mL to ciprofloxacin. CONCLUSION The increasing rates of antimicrobial resistance encountered among non-typhoidal Salmonella necessitate the judicious use of these drugs in humans. Moreover, these findings support the concern that the use of quinolones in animal feed may lead to an increase in resistance and should be restricted.

Outcome of Dialysis Access-Related Septicemia among Diabetics following Optimized AV-Fistula Placement

Background: AV fistula (AVF) is the safest of vascular accesses with lowest infection rates; yet only 23% patients used AVF during 1997 in USA. The lower prevalence of AVF among diabetics on hemodialysis (HD) places them at a higher risk of vascular-access-related septicemia (VRS) and ensuing mortality. In this study we assessed the outcome of VRS after maximizing the frequency of native AVF in this largest growing population on HD. Methods: Study included 218 patients, 63 diabetics and 155 nondiabetics on HD, through July 1996 to July 2000 when National Kidney Foundation-Dialysis Outcome and Quality Initiative (NKF-DOQI) set goal was accomplished with overall 72% of functioning AVF (57.2% diabetics and 78.1% nondiabetics) through joint efforts of nephrologists and vascular surgeons. Results: Overall, 10.6% patients per year developed VRS through 125 episodes, over 10,464 patient-months, recording 1.19 episodes per 100 patient-months. In the diabetic group, 13.87% patients per year had VRS during 44 episodes with 1.45 episodes per 100 patient-months while 1.08 episodes per 100 patient-months were recorded in nondiabetics with 9.35% per year having VRS during 81 episodes. Collectively, catheters recorded 1.5 folds higher VRS episodes in diabetic than in nondiabetic group. Mortality of 9.28% per year in diabetic group as compared to that of 6.45% per year in nondiabetic group [RR-1.436, 95% CI (0.778–2.651)] was observed, while overall mortality of 7.5% per year recorded is a good deal lower than 12–22% reported. Conclusion: The NKF-DOQI set aim of dialyzing over 50% patients through AVF is attainable in diabetics as well. Optimizing AVF is a viable approach to lessen VRS related mortality in diabetics on HD. Our continued dependence on vascular catheters is largely responsible for higher mortality in diabetics than nondiabetics on HD due to lack of cagily established pre-ESRD program for diabetics.

Remarkable resemblance in the mode of transmission of HCV infection among haemodialysis patients and IVDAs

Hepatitis C virus (HCV) infection is widespread among patients on long term haemodialysis (HD) and among intravenous drug abusers (IVDAs). However, there appear to be striking similarities in the mode of transmission between the two groups as both are at high risk for parenterally transmitted HCV infection. The indispensable requirement of having a vascular access site possibly adds to the risk of acquiring HCV infection among patients on long term HD through nosocomial transmission, especially in high HCV prevalence units. Preliminary data suggest that among various types of vascular access used for HD, arteriovenous fistula …