Nasal Carriage of Methicillin‐Resistant Staphylococcus aureus Among Paramedical Students at Pokhara University, Nepal

One of the important sources of Staphylococci which causes nosocomial infections, is the nasal carriage of Staphylococci among Health Care Workers (HCWs). The commonest antibiotic which is preferred for the treatment of the methicillin and multi drug resistant Staphylococcal infections is clindamycin. The inducible clindamycin resistance in Staphylococci is not detected by the routine antibiotic susceptibility testing and it results in treatment failures. The present study was undertaken to know the prevalence of constitutive and inducible clindamycin resistance and its correlation with the methicillin resistance among the nasal isolates of Staphylococci which were obtained from different HCWs. Nasal swabs were collected from 206 HCWs and they were processed. The Staphylococci which were isolated were tested for methicillin resistance by using cefoxitin (30 μg) discs. The inducible clindamycin resistance was tested by using erythromycin (15 μg) and clindamycin (2μg) discs and the D test according to the CLSI guidelines. Inducible clindamycin resistance was seen in 21(16.40%) of the S.aureus and 14 (7.56%) of the coagulase negative Staphylococcal isolates. Constitutive clindamycin resistance was seen in 23(17.96%) of the S.aureus and 43(23.24%) of the coagulase negative Staphylococcal isolates. The inducible and constitutive clindamycin resistance was more common among the methicillin resistant Staphylococcal isolates. The prevalence of inducible and constitutive clindamycin resistance in the nasal Staphylococcal isolates which were obtained from the HCWs was high, especially among the methicillin resistant Staphylococci. The D test which is recommended by the CLSI should be routinely done to detect inducible clindamycin resistance, to prevent treatment failures.

Introduction and Objectives: Transmission of methicillin-resistant Staphylococcus aureus (MRSA) from healthcare workers is one of the most frequent causes of nosocomial infections globally. There is a significant burden of nosocomial MRSA infections in low and low-middle income countries (LMICs), including Nepal. The present study investigated the rate of nasal carriage of MRSA among the healthcare workers in a tertiary care hospital, in Kathmandu, Nepal with emphasis on inducible macrolide-lincosamide-streptogramin B (iMLSB) resistance. Material and method: The study was conducted at Star Hospital, Lalitpur, Nepal, from September 2022 to November 2022. Healthcare workers (HCWs) working at the diffeerent departments of the hospital were enrolled. Nasal swabs from both anterior nares of HCWs were collected aseptically and cultured on Mannitol Salt agar. S. aureus was identified by Gram stain and standard biochemical tests. Antibiotic susceptibility of S. aureus was performed by disc diffusion method. MRSA isolates were detected phenotypically by disc diffusion method using cefoxitin disc (30 µg), and inducible clindamycin resistance was detected phenotypically by the D-zone test. Results: Total 105 HCWs were enrolled in the study. Out of 105 HCWs, 14 (13.3%) were positive for S. aureus among which 6 (5.7%) were MRSA carriers. The nasal carriage of MRSA was highest among doctors (16.7%) and the HCWs of the post-operative department (14.3%). All the isolated MRSA were susceptible to chloramphenicol and vancomycin. Inducible MLSB resistance was detected in 33.3% MRSA while the rate was 21.4% in all isolated S. aureus. Conclusion: The study demonstrated that HCWs could be the potential source of nosocomial infection by methicillin and inducible clindamycin resistant S. aureus. Thus, preventive measures should be initiated to mitigate the risk of its spread and the test for detection of inducible clindamycin resistance should be incorporated into the routine antibiotic susceptibility testing in hospital settings. IMC J Med Sci. 2024; 18(1):005. DOI: https://doi.org/10.55010/imcjms.18.005 *Correspondence: Gaurab Pandey, Non-Communicable Disease Laboratory, National Public Health Laboratory, Teku, Kathmandu, 44600, Nepal; E-mail: pandeygaurab67@gmail.com

BackgroundCommunity nasal meningococcal carriage rates are high across Africa. Meningococcal infections are major causes of morbidity and mortality in the continent; especially among children and adolescents. This study aimed to determine the prevalence of nasal carriage and antibiotic susceptibilities of meningococcal isolates from healthy Ethiopian children and adolescents.MethodA cross-sectional study was conducted in one of the sub-cities of Addis Ababa, Ethiopia. Nasal swabs were collected and processed for identification, serogrouping and testing susceptibilities for three antibiotics using standard microbiological techniques. Data on epidemiologic risk factors were collected using a structured questionnaire and the magnitude of their association with carriage was assessed using bivariate and multivariate analysis.ResultA total of 240 samples were collected (115 from males and 125 from females). The mean age of study participants was 11.1 years. The prevalence of nasal carriage for Neisseria meningitidis was 20.4% (49/240). Carriage was significantly higher among children living under crowded conditions (OR 1.268; 95% CI: 1.186–1.355; p = 0.006). The predominant serogroups were W135–20/49 isolates (40.8%) and C—12/49 isolates (24.5%) and 83.7% of meningococci were sensitive for Ciprofloxacin. In contrast, isolates showed high resistance to Ceftriaxone (69.4%) while only 4.2% were sensitive for Penicillin. Multi-drug resistance was documented for 14.3% of the isolates.ConclusionsMeningococcal carriage rate was found to be high with higher rates associated with children and adolescents living in crowded living conditions. Predominant isolates were of serogroup W135 and C and the isolates showed marked susceptibility to Ciprofloxacin and resistance to Ceftriaxone and Penicillin.

Objective: This study aimed to determine prevalence of inducible and constitutive clindamycin resistance among clinical S. aureus isolates and also study their association with methicillin resistance. Methods: A cross-sectional study including 140 non-duplicate isolates of S. aureus was done. Isolates were identified by standard microbiological methods and methicillin resistance was detected by cefoxitin disc diffusion method. Inducible clindamycin resistance was detected by D-test. Results: Prevalence of inducible and constitutive clindamycin resistance was 12.10% and 7.90% respectively. Constitutive and inducible resistance was associated with MRSA. An unusual phenotype, erythromycin sensitive and clindamycin resistance, was detected in 2 MRSA isolates. Conclusions: Inducible and constitutive clindamycin resistance is low in our setting. Constitutive and inducible resistance was associated with MRSA. However the trends in resistance vary in different places. D-test reporting should be done routinely which will allow clinicians to opt for clindamycin judiciously and avoid potential treatment failure. Keywords: Clindamycin resistance, MLSBi, D-test, MRSA, Nepal

Staphylococcus aureus () is recognized as one of the most common microrganisms causing nosocomial and community-acquired infections. Nasal carriage of Staphylococcus aureus is becoming an increasing problem among healthcare workers and in the healthy community individuals. General populations with persistent Staphylococcus aureus nasal carriage rates at 10% to 20%, and up to 50% are intermittent carriers. Furthermore, carrier levels of 25% have been reported among healthcare workers(HCW’s). Strains with inducible clindamycin resistance (ICR) are difficult to detect in the routine laboratory as they appear to be resistant to erythromycin and sensitive to clindamycin in vitro when not placed adjacent to each other. In such cases, in vivo treatment with clindamycin may select constitutive erm mutants leading to clinical therapeutic failure. 100 nasal swabs samples were collected during January 2019 to November 2019. Isolates were identified using standard microbioloical procedures and MRSA determined by the disk diffusion method. The D-test was performed for detection of Inducible clindamycin resistance isolates with Clinical Laboratory Standard Institute guidelines.: Out of 18 isolated, 33.3 were MRSA. Of 18 isolates tested for ICR by D-test, 6 (33.3%) yielded inducible resistance. Inducible clindamycin resistance was found to be significantly higher among MRSA than MSSA isolates. Beside personal hygiene practices of healthcare workers, regular implementation of infection control practices, including screening of nasal carriages and microbial flora in our hospital are necessary to prevent spread of MRSA. It is also advisable to perform routine nasal decolonization of healthcare workers using mupirocin ointment to prevent transmission of these organisms.

The resistance to antimicrobial agents among Staphylococci is an increasing problem. Clinical laboratories should perform D test routinely to guide the clinicians about the inducible clindamycin resistance and to prevent misuse of antibiotics. Study aimed to isolates the Inducible and Constitutive clindamycin Resistance in Staphylococcus aureus in various clinical samples. We analyzed the performance of disk diffusion method in 183 Staphylococci aureus strains obtained from various clinical samples of the patients collected from September 2018 to February 2020 at a tertiary care centre, Meerut. Inducible clindamycin resistance was tested by ‘D test’ as per CLSI guidelines. 142(77.6%) of isolates were found to be methicillin resistant (MRSA) and 41 (22.4%) tested sensitive to cefoxitin i.e., methicillin sensitive (MSSA). Inducible resistance and constitutive resistance were found to be higher in MRSA as compared to MSSA). The D test method showed to be simple and easy in the detection of inducible (iMLS) and constitutive clindamycin resistance (cMLS).

Clindamycin is an alternative antibiotic in the treatment of Staphylococcus aureus (S.aureus) infections, both in infections by methicillin susceptible and resistant (MSSA and MRSA) strains. The major problem of use of clindamycin for staphylococcal infections is the presence of inducible clindamycin resistance that can lead to treatment failure in such infections. To determine inducible and constitutive clindamycin resistance among clinical isolates of S. aureus in a tertiary care centre of sub Himalayan region of India. A total of 350 isolates of S. aureus from various clinical samples were subjected to routine antibiotic sensitivity testing by Kirby Bauer disc diffusion method. Methicillin resistance was detected by cefoxitin (30μg) disc. All isolates were subjected to inducible clindamycin resistance was by Clinical Laboratory Standards Institute (CLSI) recommended D test. Among 350 S.aureus isolates, 82 (23.42%) were MRSA and 268 (76.57%) were MSSA. Erythromycin resistance was detected in 137 (39.14%) isolates. Erythromycin resistance in MRSA and MSSA was 71.6% and 29.36% respectively. Overall clindamycin resistance was seen in 108 (30.85%) isolates. Constitutive MSLB phenotype predominated (29.62% MRSA; 13.38% MSSA) followed by iMLSB (28.39% MRSA; 9.29% MSSA) and MS phenotypes (13.58% MRSA; 6.69%MSSA). Both inducible and constitutive clindamycin resistance was significantly higher (p=0.00001, 0.0008 respectively) in methicillin resistant strains than in methicillin susceptible strains. The present study gives a magnitude of clindamycin resistance among clinical isolates of S. aureus from this region of the country. Our study recommends routine testing of inducible clindamycin resistance at individual settings to guide optimum therapy and to avoid treatment failure.

Introduction: No studies have investigated Community-Acquired Methicillin-Resistant Staphylococcus aureus (CA-MRSA) nasal carriage rate in the Turkish Cypriot community up to now. The aim of this study was to investigate (i) The prevalence of CA-MRSA nasal carriage in the Turkish Cypriot community, (ii) The association of previously identified risk factors with CA-MRSA. Materials and Methods: Our study is a cross-sectional study conducted in Northern Cyprus in 2019 with 487 randomly selected and voluntary participants. In this study, a questionnaire was distributed, and the relationship between nasal CA-MRSA carriage and risk factors was investigated. In addition, the presence of CA-MRSA was determined by taking a nasal swab sample. Results: In this study, the prevalence of nasal CA-MRSA carriage in the Turkish Cypriot society was 6.98% (34/487). Marital status was found to be the only significant risk factor associated with CA-MRSA carriage (p= 0.035) in the study. However, it was found that individuals exposed to risk factors of “hospitalization during the previous year” and “using antibiotic during the last year” were 1.6 and 3.25 times higher than those who did not, respectively. Conclusion: In this study, “marital status” was the only statistically significant risk factor associated with CA-MRSA carriage. Furthermore, the prevalence of nasal CA-MRSA carriage in the Turkish Cypriot population was found to be higher than developed countries. In this context, it is essential to develop health strategies for the sustainability of TK-MRSA carriage surveillance and to reduce carriage.

Background: Staphylococcus aureus ( S. aureus) is a common cause of nosocomial and community acquired infections worldwide. Nasal carriage of S. aureus acts as an endogenous reservoir for clinical infections in the colonized individual and also as a source of cross-colonization for community spread. Infections caused by S. aureus range clinically from minor skin infections to severe life threatening infections; with mortality rates ranging from 6 to 40 %.Treatment of staphylococcal infections has now become more challenging with emergence of methicillin resistant S. aureus (MRSA) strains; which are often also multidrug-resistant. Objectives: The present study was conducted to screen for the prevalence rate of nasal carriage of S. aureus among paramedical students studying at the Faculty of Allied Medical Sciences, Pharos University, Alexandria, Egypt. The study also aimed at studying the validity of Dry Spot Staphytect Latex Kit as a rapid screening test for identification of S. aureus. Methods: Nasal swabs were collected from 100 volunteer students over a period of three months (February-April 2015). Swabs were cultured both on blood agar and mannitol salt agar and all isolates that were confirmed microscopically and biochemically as S. aureus were tested for antibiotic sensitivity using modified Kirby Bauer technique. Dry Spot Staphytect Latex Kit was evaluated as a rapid method for identification of S. aureus, setting the positive result of tube coagulase test as a gold standard. Results: The nasal carriage rate of S. aureus detected was 34%, 18 % of which were MRSA strains. The highest level of sensitivity to antibiotics among S. aureus isolates was recorded for vancomycin and mupirocin, (97.1%) each. Regarding MRSA strains, 100% were sensitive to mupirocin and 100% were resistant to oxacillin. Dry Spot Staphytect Latex Kit had a sensitivity of 97.06 %, a specificity of 96.97 %, a positive predictive value of 94.29 %, a negative predictive value of 98.46 % and an accuracy of 97 % in rapid identification of S. aureus. Conclusion: Paramedical university students are a high risk group for nasal carriage of S. aureus and MRSA. Dry Spot Staphytect latex test is recommended for use as an efficient rapid, sensitive, specific and accurate screening test for S. aureus and MRSA. Key words: S. aureus , MRSA, nasal carriage, paramedical students, Dry Spot Staphytect Latex Kit

BackgroundStaphylococcus aureus is a cardinal source of community- and hospital-acquired infection. HIV infection is a well-recognized risk factor for methicillin-resistant S. aureus (MRSA) carriage and infection. Intrinsically developed antibiotic resistance has sharply increased the burden of MRSA which is often associated with morbidity and mortality of the patients. Moreover, nasal carriage of S. aureus plays a significant role in spread of community-associated (CA) S. aureus infections. Methods This study was conducted from June 2016 to December 2016 at National Public Health Laboratory (NPHL), Kathmandu, with an aim to assess the rate of S. aureus nasal carriage and MRSA carriage among HIV-infected and non-HIV patients. A total of 600 nonrepeated nasal swabs were analyzed following standard microbiological procedures, where 300 swabs were from HIV-infected patients while remaining 300 were from non-HIV patients. The isolates were identified on the basis of colony characteristics and a series of biochemical tests. The antibiotic susceptibility test (AST) was performed by the modified Kirby–Bauer disc diffusion method. Inducible clindamycin resistance in isolates was confirmed by the D-test method. Results Overall, out of 600 nasal swabs of patients tested, 125 (20.8%) were S. aureus nasal carriers which included 80 out of 300 (26.66%) among HIV-infected patients and 45 (15%) out of 300 among non-HIV patients, and the result was statistically significant (p=0.0043). Among the isolated S. aureus, 11 (13.8%) MRSA were confirmed in HIV-infected while 3 (6.7%) MRSA were detected from non-HIV patients. A higher number of S. aureus carriers was detected among HIV-infected males 40 (26.49%), whereas MRSA carriage was more prevalent among HIV-infected females 7 (5.1%). Among the HIV-infected, patients of age group 31–40 years were the ones with highest carriage rate 36 (45%), while in non-HIV patients, the highest rate 13 (28.9%) of carriage was detected among the patients of age group 21–30 years. Statistically significant difference was found between S. aureus carriage and HIV infection in patients (p < 0.05). Higher rate 2/3 (66.7%) of inducible clindamycin resistance in MRSA was detected from non-HIV patients in comparison to HIV-infected patients 7/11 (63.63%) while the result was statistically insignificant (p > 0.05). All the MRSA isolates (100%) were resistant against co-trimoxazole while ciprofloxacin showed high rate of sensitivity towards both MSSA and MRSA. None of the isolates were detected as VRSA. The major factors associated with nasal colonization of S. aureus were close personal contact, current smoking habit, and working or living in a farm (p < 0.05). Conclusion Regular surveillance and monitoring of MRSA nasal carriage and antibiotic susceptibility pattern are of prime importance in controlling S. aureus infections especially in high risk groups like HIV-infected patients.

Objectives: One of the potential risk factors for nosocomial staphylococcal and Methicillin-resistant Staphylococcus aureus (MRSA) infections is colonization of the anterior nares of HCWs, and from there they may spread to the patients, which may cause a burden on the health-care system. In this context, we made an attempt to compare the Staphylococcal and MRSA nasal carriage and their susceptibility to Mupirocin in students who are exposed to the health-care system and those who are not. Methods: Nasal swabs were collected from 100 paramedical students as the study group and 100 non-medical students as the control group, all in the age group between 18 and 21 years. 5% sheep blood agar and mannitol salt agar were used to isolate S. aureus, and antibiotic sensitivity was done by Kirby Bauer Disc Diffusion Technique. Cefoxitin disc (30 μg) and Vancomycin screen agar were used to detect MRSA and Vancomycin resistance, respectively. A 5 μg disc of Mupirocin was used to test the susceptibility of Mupirocin. Results: Nasal carriage rate of S. aureus and MRSA was 23% and 8% in Paramedical students and 17% and 4% in Nonmedical students respectively. 83% of isolates from paraclinical students and 95% of isolates from non-medical students were susceptible to linezolid. Out of 12 MRSA strains from both groups only one strain showed resistance to Mupirocin. Conclusions: Nasal carriage of S. aureus and MRSA and antibiotic resistance of isolated strains were more common in paramedical students and also in female students. Vancomycin resistance was not observed in MRSA strains from male students. Mupirocin resistance, even in a single case, needs to be addressed.

Nasal carriage of Staphylococcus aureus is becoming an increasing problem among healthcare workers and community individuals. To determine the prevalence of methicillin-resistant S. aureus (MRSA) nasal colonization and inducible clindamycin resistance (ICR) of S. aureus among healthcare workers at Soba University Hospital and community members in Khartoum State, Sudan. Five hundred nasal swabs samples were collected during March 2009 to April 2010. Isolates were identified using conventional laboratory assays and MRSA determined by the disk diffusion method. The D-test was performed for detection of ICR isolates with Clinical Laboratory Standard Institute guidelines. Of the 114 S. aureus isolated, 20.2% represented MRSA. The occurrence of MRSA was significantly higher among healthcare worker than community individuals [32.7% (18/55) vs. 6.9% (5/59)] (p=0.001). Overall the 114 S. aureus isolates tested for ICR by D-test, 29 (25.4%) yielded inducible resistance. Significantly higher (p=0.026) ICR was detected among MRSA (43.5%) than methicillin-susceptible S. aureus (MSSA) (20.9%). MRSA nasal carriage among healthcare workers needs infection control practice in hospitals to prevent transmission of MRSA. The occurrence of ICR in S. aureus is of a great concern, D- test should be carried out routinely in our hospitals to avoid therapeutic failure.

Background: Staphylococcus aureus is Gram positive cocci. The pyogenic bacteria which is responsible for a variety of diseases that ranges in severity from mild skin and soft tissue infections to life-threatening conditions such as endocarditis, pneumonia, and sepsis. There is a scenario of increasing Methicillin-resistant Staphylococcus aureus (MRSA) infections, the macrolide-lincosamide-streptogramin B (MLSB) group of antibiotics they have different structure with same mechanism of action which serves as one good alternative. There is a frequency of increasing Methicillin Resistant Staphylococcus aureus (MRSA) infections and their change in antimicrobial resistance pattern. There is a concern about use of this antibiotic in the presence of Erythromycin resistance because of the possibility of inducible resistance among the members of Macrolide, lincosamide, Strepto-gramin B (MLSB) group. The invitro resistance exhibited by Staphylococcus aureus to erythromycin, Clindamycin, and other drugs of MLSB groups is due to the expression of ribosomal methylases(erm) genes. The detection of inducible Clindamycin resistance can limit the effectiveness of these drugs. Objective of the study: To isolate of Staphylococcus aureus from various clinical samples to differentiate between Methicillin resistant Staphylococcus aureus (MRSA) and Methicillin sensitive Staphylococcus aureus (MSSA) by conventional methods. To detect inducible and constitutive Clindamycin resistance in Staphylococcus aureus isolates by D test. To detect ermA gene responsible for resistance by PCR. Methodology: This cross sectional study was done for a period of six months. Totally 106 Staphylococcus aureus isolates was obtained various clinical samples were processed using standard guidelines. Result: From the 106 isolates of Staphylococcus aureus 67(63.3%) were MSSA and 39(36.7%) were MRSA. D-test was positive in n=9 of the n=21 MRSA and n=17 of the n=85 MSSA, which denotes inducible Clindamycin resistance. N- 9 of MRSA and n=13(22%) of MSSA showed Constitutional Clindamycin resistance. The statistics show that there is a significant Difference in constitutive resistance between MRSA and MSSA. In India ermA gene is most prevalent, out of 22 d-test positive n=13 ermA gene were detected (n=3-MRSA and n=10-MSSA) by using conventional PCR. Conclusion: The MLSB family of antibiotics is one such alternative and CD is preferred. Clinical microbiology laboratories should report inducible Clindamycin resistance in Staphylococcus aureus and D-test can be used as a simple, auxiliary and reliable method to Delineate inducible and constitutive Clindamycin resistance in routine clinical laboratories.

Background: Healthcare workers (HCWs) and medical students can be asymptomatic carriers in transmitting methicillin resistant and susceptible Staphylococcus aureus (MRSA and MSSA). Studying epidemiological and antibiotic susceptibility data is necessary to limit the spread of infections, help with treatment and understand the transmission dynamics of MSSA and MRSA. Our study assessed the rate of MSSA and MRSA nasal carriage and its antibiogram among medical students in basic and clinical years at the University of Jordan. Methods: A total of 210 nasal swabs were randomly collected from participants. MSSA and MRSA were identified by culture, biochemical and other phenotypical analysis methods. Antibiotic susceptibility was determined by the disc diffusion method. Results: The nasal carriage of MSSA was 6.6% and 11.4% and that of MRSA was 1.9% and 2.8% among basic and clinical years, respectively. There was no significant difference for the nasal carriage of MSSA and MRSA among basic and clinical year students (p value ≥ 0.05). MSSA resistance ranged between 25% and 33% for trimethoprim-sulfamethoxazole, tetracycline and ciprofloxacin. For MRSA, the highest resistance was to trimethoprim-sulfamethoxazole and tetracycline (67% to 100%), followed by gentamicin and ciprofloxacin (33% to 67%), in all participants in the study. Conclusion: The difference in the carriage rates of MSSA and MRSA among basic and clinical students was statistically insignificant. The continuous awareness and implementation of infection control procedures and guided patient contact are recommended. The results might also suggest that healthcare workers could be victims in the cycle of MRSA nasal carriage, a theory that needs further study.

BackgroundElevated 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 MethodsThis 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.ResultsOverall, 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.ConclusionsSignificantly 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.