Methicillin-resistant Staphylococcus Aureus Septicemia Research Articles

Assessing the impact of the early COVID-19 era on antibiotic-resistant threats in inpatient settings: A mixed Poisson regression approach

During the COVID-19 pandemic, increased antibiotic prescribing and infection prevention challenges coincided with antibiotic-resistant (AR) infection increases. Clostridioides difficile (C difficile) and methicillin-resistant Staphylococcus aureus (MRSA) are serious, costly AR threats. Health inequities in pandemic-era AR infections are not well-characterized. North Carolina statewide inpatient admissions were used to determine monthly admission rates and admission rate ratios (RRs) for C difficile and MRSA infections comparing 2017-2019 (prepandemic) to 2020 (pandemic exposure) using mixed-model Poisson regression adjusted for age, sex, comorbidities, and COVID-19. We assessed effect measure modification by admissions' community-level income, county rurality, and race and ethnicity. Mean total costs by infection type were compared. With pandemic exposure, C difficile (adjusted RR=0.90 [95% confidence interval [CI] 0.86, 0.94]) and MRSA pneumonia (adjusted RR=0.97 [95% CI 0.91, 1.05]) decreased, while MRSA septicemia (adjusted RR=1.13 [95% CI 1.07, 1.19]) increased. Effect measure modification was not detected. C difficile or MRSA coinfection nearly doubled mean costs among COVID-19 admissions. Despite decreases in C difficile and most MRSA infections, the early COVID-19 pandemic period saw continued increases in MRSA septicemia admissions in North Carolina. Equitable interventions to curb increases and reduce health care costs should be developed.

Trends in methicillin-resistant Staphylococcus aureus bloodstream infections using statewide population-based surveillance and hospital discharge data, Connecticut, 2010-2018.

We compared methicillin-resistant Staphylococcus aureus (MRSA) bloodstream infections (BSIs) captured by culture-based surveillance and MRSA septicemia hospitalizations captured by administrative coding using statewide hospital discharge data in Connecticut from 2010 to 2018. Observed discrepancies between identification methods suggest administrative coding is inappropriate for assessing trends in MRSA BSIs.

Concurrent methicillin-resistant Staphylococcus aureus septicemia and pyomyositis in a patient with dengue hemorrhagic fever: a case report

BackgroundConcurrent presence of dengue hemorrhagic fever (DHF), tropical pyomyositis and septicemia due to methicillin-resistant Staphylococcus aureus (MRSA) in a previously healthy person has never been reported. These three conditions even individually are potentially fatal. “Here we describe a case of a patient contracting dengue and developing DHF along with concurrent pyomyositis likely to be due to MRSA, leading to MRSA septicemia with abscesses formed by MRSA”.Case presentationA 44-year old previously healthy Sinhalese man presented on day 3 of the illness with fever, headache, arthralgia and myalgia and watery loose stools. His pulse rate was 76/min, blood pressure was 110/80 mmHg, while cardiovascular, respiratory and abdomen examination findings were unremarkable. The test for the dengue NS1 antigen was positive on the same day. We have diagnosed dengue and started managing him symptomatically as per the current national guidelines. The patient developed DHF with bilateral pleural effusion and ascitis. On the day 5 he developed severe myalgia, tenderness and non pitting edema of lower limbs especially in the thighs. His creatine kinase levels were high and an ultrasound scan confirmed myositis of both thighs. We suspected myositis due to dengue but investigated for possible simultaneous sepsis as well. On day 9 his blood culture became positive for MRSA. Considering the sensitivity of the bacteria intravenous vancomycin and ciprofloxacin was administered for 21 days. He developed a small abscess at the site of the first intravenous access and a large one above the ankle on the left. On day 12 the latter was drained and the pus culture yielded MRSA sensitive to the same antibiotics. The rapid test for dengue IgM was negative initially but later a positive MAC-ELISA test entrenched dengue infection. After improvement he was sent home on day 33 of the illness. He has developed two other abscesses in the proximity of the drained one and they were drained on day 57. The patient recovered.ConclusionsWhen dengue patients develop symptoms and signs of myositis, prompt investigations for pyomyositis and the treatment can save lives.

Endogenous Endophthalmitis in Patients with MRSA Septicemia: A Case Series and Review of Literature

Purpose: To report the presentation, predisposing factors, clinical features and outcome in 6 eyes of 3 patients with endogenous endophthalmitis secondary to methicillin resistant staphylococcus aureus (MRSA) septicaemia.Methods: Retrospective review of case records of 3 patients who were treated for endogenous endophthalmitis secondary to MRSA septicaemia in a tertiary referral institution.Results: All three patients had systemic predisposition to endogenous endophthalmitis (diabetes, urosepsis). Two patients presented within 1 week of onset of visual symptoms and the third after 3 months. Blood culture was positive for MRSA in all patients. Visual and anatomical improvement was noted in two patients who presented early. The third patient’s visual outcome despite early treatment with intravitreal antibiotics and vitrectomy was not satisfactory.Conclusion: Endogenous endophthalmitis by MRSA is a rare but serious condition. Early and specific therapy based on reliable detection of the underlying microorganism is needed for good anatomical and functional outcome.

Substantial shifts in ranking of California hospitals by hospital-associated methicillin-resistant Staphylococcus aureus infection following adjustment for hospital characteristics and case mix.

States have established public reporting of hospital-associated (HA) infections-including those of methicillin-resistant Staphylococcus aureus (MRSA)-but do not account for hospital case mix or postdischarge events. Identify facility-level characteristics associated with HA-MRSA infection admissions and create adjusted hospital rankings. A retrospective cohort study of 2009-2010 California acute care hospitals. We defined HA-MRSA admissions as involving MRSA pneumonia or septicemia events arising during hospitalization or within 30 days after discharge. We used mandatory hospitalization and US Census data sets to generate hospital population characteristics by summarizing across admissions. Facility-level factors associated with hospitals' proportions of HA-MRSA infection admissions were identified using generalized linear models. Using state methodology, hospitals were categorized into 3 tiers of HA-MRSA infection prevention performance, using raw and adjusted values. Among 323 hospitals, a median of 16 HA-MRSA infections (range, 0-102) per 10,000 admissions was found. Hospitals serving a greater proportion of patients who had serious comorbidities, were from low-education zip codes, and were discharged to locations other than home were associated with higher HA-MRSA infection risk. Total concordance between all raw and adjusted hospital rankings was 0.45 (95% confidence interval, 0.40-0.51). Among 53 community hospitals in the poor-performance category, more than 20% moved into the average-performance category after adjustment. Similarly, among 71 hospitals in the superior-performance category, half moved into the average-performance category after adjustment. When adjusting for nonmodifiable facility characteristics and case mix, hospital rankings based on HA-MRSA infections substantially changed. Quality indicators for hospitals require adequate adjustment for patient population characteristics for valid interhospital performance comparisons.

Implantable cardioverter defibrillator lead-related methicillin resistant Staphylococcus aureus endocarditis: Importance of heightened awareness

Methicillin resistant Staphylococcus aureus (MRSA) septicemia is associated with high morbidity and mortality especially in patients with immunosuppression, diabetes, renal disease and endocarditis. There has been an increase in implantation of cardiac implantable electronic devices (CIED) with more cases of device-lead associated endocarditis been seen. A high index of suspicion is required to ensure patient outcomes are optimized. The excimer laser has been very efficient in helping to ensure successful lead extractions in patients with CIED infections. We present an unusual case report and literature review of MRSA septicemia from device-lead endocarditis and the importance of early recognition and prompt treatment.

Characterization of β-lactam antibiotic-induced vancomycin-resistant MRSA (BIVR) in a patient with septicemia during long-term vancomycin administration

It was reported that some methicillin-resistant Staphylococcus aureus (MRSA) show resistance to vancomycin (VCM) and beta-lactam antibiotics; thus, they are termed beta-lactam antibiotic-induced VCM-resistant MRSA (BIVR). The VCM resistance of MRSA is induced by the administration of beta-lactam antibiotics, but this phenomenon can be difficult to detect in the clinical laboratory. We detected the BIVR strain in a 64-year-old man who had had a ventilator tube inserted directly into the windpipe during long-term VCM therapy. The patient was diagnosed with MRSA pneumonia and septicemia on July 5, 2007, and sulbactam/ampicillin (SBT/ABPC) was administered for 5 days. However, the fever recurred, and administration of VCM was resumed for 7 days from July 19. Fever developed again, and VCM was administered again for 14 days from September 30. BIVR and VCM-low-sensitive MRSA were isolated from blood on October 18 and 22, although the VCM trough concentration was 10.2 microg/ml. On October 27, we changed to a combination of fosfomycin (FOM) and arbekacin (ABK), and thereafter the fever quickly decreased and the clinical symptoms abated. We isolated five MRSA strains from the blood of the patient, three strains of VCM-sensitive MRSA, one strain of BIVR, and one strain of a VCM-low-sensitive MRSA. The DNA band patterns determined by pulsed-field gel electrophoresis were completely identical except for the VCM-low-sensitive MRSA, which was missing one band. Furthermore, the VCM-low-sensitive MRSA became sensitive to beta-lactam antibiotics. Our results indicate the possibility that long-term VCM therapy is one of the factors that allow BIVR or VCM-low-sensitive MRSA to emerge, and this allows VCM therapy for MRSA to fail.

Methicillin resistant Staphylococcus aureus infections following cardiac surgery: incidence, impact and identifying adverse outcome traits☆

To assess the incidence and impact of Methicillin-resistant Staphylococcus aureus (MRSA) infections on cardiac surgery outcomes and to identify adverse outcome traits. Retrospective analysis of prospectively collected data from cardiac surgical and microbiology databases between April 2000 and March 2005. The overall and yearly incidence of positive MRSA cultures was examined along with the distribution of clinical infections and the associated mortality. Pre-operative patient characteristics were analysed between non-survivors and survivors of MRSA infections. Multivariate logistic regression was used to assess the relationship between pre-operative patient characteristics and in-hospital mortality in patients with MRSA. A comparison of post-operative outcomes between non-survivors and survivors of MRSA infections was also carried out and included in the logistic regression analysis. There were 319 patients with positive MRSA cultures during the study period with an overall incidence of 3.9%. Yearly incidence ranged from 2.4% to 5.2%. There were 120 carriers with pre-operative positive cultures of which 25 developed clinical surgical infections leaving 224 patients as the study group. Overall mortality in patients with MRSA during the study period was 12.9%(41/319). Mortality in the study group was 17.8% (40/224). Mortality comparison between MRSA and non-MRSA mediastinitis was 26.7%(8/30) and 17.1%(13/76), respectively (p=0.26). Mortality between MRSA and non-MRSA septicaemia was 46.9% (15/32) and 52.9% (37/70) (p=0.57). Applying the logistic EuroSCORE to the MRSA patients revealed that non-survivors had a significantly higher pre-operative risk of 10.4% compared to survivors with a pre-operative risk of 6.2% (p=0.003). Renal dysfunction and poor ejection fraction were found to be pre-operative factors associated with mortality in MRSA patients following the multivariate logistic regression analysis. Non-survivors had longer stays on intensive care, longer ventilation times, and were more likely to require support with balloon pumps and haemofiltration. MRSA septicaemia and length of ventilation were significantly associated with mortality in MRSA patients ahead of pre-operative characteristics. The incidence of MRSA is low, but carries a high mortality. MRSA septicaemia and mediastinitis have the highest associated mortality; however, this is not significantly different from non-MRSA infections. Patients with MRSA who die have higher pre-operative risk and have a poorer post-operative course than survivors.

Posterior pericardial approach for ascending-to-descending aortic bypass for anastomotic leak of infected interpositional graft

Clinical Summary A 25-year-old male car driver sustained multiple injuries in a road traffic crash, including hepatic laceration, aortic transection, and right humeral and femoral fractures. He underwent emergency laparotomy and partial hepatectomy. A subsequent aortogram revealed a pseudoaneurysm distal to the left subclavian artery. Repair of the transected aorta was performed with the proximal descending aorta replaced with an 18-mm woven Dacron graft through a left thoracotomy. Recovery was complicated by methicillin-resistant Staphylococcus aureus (MRSA) infection of a large sacral sore, which required a rotation flap, and bilateral MRSA empyema, which was managed with Cope loop drainage and 6 months of intravenous vancomycin. Three years later, the patient returned with hemoptysis. Computed tomographic scan and aortogram demonstrated leakage from the distal end of the aortic graft resulting in a pseudoaneurysm and an aortobronchial fistula. Endoluminal stenting with a 22 mm 131 mm Talent LPS stent graft (Medtronic AVE, Santa Rosa, Calif) was performed with successful occlusion of the leak. MRSA septicemia developed in the patient after the procedure, and he was treated with intravenous vancomycin and subsequently with intramuscular teicoplanin. Two years later, the patient returned with a 2-month history of hemoptysis. Computed tomographic scan of the thorax was suggestive of a recurrent leak, which was confirmed on aortogram (Figure 1). Emergency extra-anatomic ascending aorta–to–descending aorta bypass was performed with exclusion of the proximal descending thoracic aorta from which the leak arose. This was performed through a median sternotomy on full cardiopulmonary bypass via ascending aortic and right atrial cannulation. With the empty heart displaced superiorly, the distal descending aorta was accessed through a longitudinal incision in the posterior pericardium. A 16-mm woven Dacron graft was anastomosed to the distal descending thoracic aorta with a side-biting clamp. The graft was tracked posterior to the inferior vena cava and anastomosed to the right lateral aspect of the ascending aorta (Figure 2). The descending aorta between the left subclavian artery and the new distal anastomosis was excluded. At the end of surgery, the heart was edematous; the chest was closed 5 days later. Hemoptysis settled, and the patient made a satisfactory recovery. In view of the patient’s life-threatening complications from MRSA infection to the prosthetic grafts, he is on lifelong antiMRSA treatment. He has remained well for the past 2 years.

Combined use of alcohol hand rub and gloves reduces the incidence of late onset infection in very low birthweight infants

Objective: To assess the incidence of late onset (> 72 hours) infection and necrotising enterocolitis (NEC) in very low birthweight (VLBW) infants in two 36 month periods using two hand...

A Fatal case of MRSA Septicaemia and Gallbladder Empyema

Methicillin-resistant Staphylococcus aureus (MRSA) has become a major problem worldwide and is associated with significant morbidity and mortality. It is a particular issue in surgical patients especially vascular surgery involving prosthetic implants. We present an unusual case of MRSA gallbladder empyema and septicaemia in a previous vascular surgical patient. Teranishi et al reported a case of acute cholecystitis caused by MRSA in the Japanese literature 1 but as far as we are aware this is the first case reported in the English literature.

Cavernous sinus thrombosis secondary to MRSA septicaemia

Purpose: To report the first case of cavernous sinus thrombosis (CST) due to methicillin-resistant Staphylococcus aureus (MRSA) infection. Also, to emphasise that MRSA infection may be acquired in the community. Method: Single observational case report. Results: CST has a very high mortality and morbidity and has been reported as a rare complication of localised and systemic infection. We present the case of a 35-year-old female intravenous (IV) drug user presenting with septicaemia and heroin overdose. Following initial resuscitation, she gained consciousness but remained confused with Glasgow Coma Scale (GCS) of 8/15. The patient was febrile and there was a marked bilateral proptosis, eyelid swelling with erythema, and conjunctival chemosis. Pupils were pinpoint. Ocular movements appeared limited. In view of the high index of suspicion of CST, the patient was intubated for an urgent CT scan of the brain and orbits, which confirmed the disorder's diagnosis. High-dose IV ceftazadime, metronidazole, and flucloxacillin was commenced. Blood cultures were positive for methicillin-resistant Staphylococcus aureus (MRSA). The patient had not had any prior hospital contact. The source of infection was not identified, but the subsequent CT scan indicated multiple intracerebral abscesses and multiple cavitating abscesses of the lungs with a large pleural effusion. The patient died nine days after admission to hospital. Conclusion: MRSA infection can be acquired in the community and should be borne in mind by ophthalmologists when dealing with infections. To the authors' knowledge, this is the first case of CST secondary to MRSA sepsis.

Methicillin-resistant Staphylococcus aureus (MRSA) and Autogenous Saphenous Vein Grafts in Femoropopliteal Bypass Procedures

Abstract: Do autogenous vein grafts provide resistance to graft infection in MRSA (Methicillin resistant Staphylococcus aureus) patients undergoing vascular surgery? This paper presents two MRSA patients, who underwent femoral popliteal bypass procedure with autogenous saphenous vein grafts. Despite prophylactic measures and all necessary care, both patients had graft infections and died as a result of MRSA septicaemia. Our conclusion is that autogenous vein grafts do not provide resistance to MRSA infection.

Adverse events associated with methicillin-resistant Staphylococcus aureus in a nursing home.

Methicillin-resistant Staphylococcus aureus (MRSA) generates concern in nursing homes. Restrictive isolation precautions may be applied for indefinite periods. Adverse events driving these concerns include transmission and infection. The 721-bed Wisconsin Veterans Home in King performs approximately 645 cultures annually. The site, severity, and number of MRSA infections were determined for 69 months. Pulsed-field gel electrophoresis was performed on all initial isolates, followed by a statistical cluster analysis looking for evidence of transmission. Sixty-seven MRSA infections were identified (1.6 per 100 residents per year); many were polymicrobial, and it was difficult to determine the proportionate role of MRSA in morbidity or mortality. There was an episode of rapidly fatal MRSA septicemia in which empiric antibiotic therapy was ineffective. Twenty-one genetic strains were encountered. Statistical analysis identified 13 clusters of genetically identical strains clustered in time and space (P<.05). Infections with MRSA were identified at relatively low rates; however, the etiology of many serious nursing home infections is not determined, especially pneumonia. Statistical analysis revealed clustering and evidence of transmission. Nursing home practitioners should consider MRSA when applying empiric treatment to serious infections. We recommend a program including (1) judicious use of antibiotics, including topical agents, to reduce selection of resistant organisms; (2) obtaining and tracking cultures of infectious secretions to diagnose MRSA infections and focus antibiotic therapy; (3) universal standard secretion precautions because any resident could be a carrier; and (4) a detailed assessment and care plan for the carrier that maximizes containment of secretions and independence in activities. However, basic hygiene cannot be maintained in communal areas by some residents without restriction of activities of daily living.

Clinical experience and outcomes of community-acquired and nosocomial methicillin-resistant Staphylococcus aureus in a northern Australian hospital

Methicillin-resistant Staphylococcus aureus (MRSA) is a well-recognized cause of hospital-acquired sepsis. We reviewed the clinical features of a new variant of community-acquired MRSA originally described from the Kimberley region of northern Western Australia (WA MRSA). This strain has become an increasing cause of community- and hospital-acquired sepsis at Royal Darwin Hospital (RDH) in the Northern Territory, especially in Aboriginal Australians from remote communities. Fifty percent of WA MRSA was community-acquired, with 76% in Aboriginals. Like the MRSA from eastern Australia (EA MRSA), WA MRSA commonly caused skin sepsis but was less likely to cause respiratory or urinary infections compared with EA MRSA. Twelve out of 125 (9·6%) WA MRSA and 7/93 (7·5%) EA MRSA infections were septicaemias. Septicaemia due to WA MRSA occurred in adult medical patients, especially those with temporary haemodialysis catheters, while EA MRSA septicaemia occurred throughout the hospital. Aboriginal people were more likely to develop both community- and hospital-acquired WA MRSA septicaemia [overall relative risk (RR) 12·3 (95% CI 3·7–40·7)]. Control of WA MRSA requires policies to reduce transmission in both hospitals and communities. Community-based control programmes need support for individual patient management, improved housing and hygiene, control of skin sepsis and appropriate use of antibiotics, especially in rural Aboriginal communities in northern Australia.

Therapeutic efficacy of BO-3482, a novel dithiocarbamate carbapenem, in mice infected with methicillin-resistant Staphylococcus aureus.

The in vivo activity of BO-3482, which has a dithiocarbamate chain at the C-2 position of 1beta-methyl-carbapenem, was compared with those of vancomycin and imipenem in murine models of septicemia and thigh infection with methicillin-resistant Staphylococcus aureus (MRSA). Because BO-3482 was more susceptible than imipenem to renal dehydropeptidase I in a kinetic study of hydrolysis by this renal enzyme, the therapeutic efficacy of BO-3482 was determined during coadministration with cilastatin. In the septicemia models, which involved two homogeneous MRSA strains and one heterogeneous MRSA strain, the 50% effective doses were, respectively, 4.80, 6.06, and 0.46 mg/kg of body weight for BO-3482; 5.56, 2.15, and 1.79 mg/kg for vancomycin; and >200, >200, and 15.9 mg/kg for imipenem. BO-3482 was also as effective as vancomycin in an MRSA septicemia model with mice with cyclophosphamide-induced immunosuppression. In the thigh infection model with a homogeneous MRSA strain, the bacterial counts in tissues treated with BO-3482-cilastatin were significantly reduced in a dose-dependent manner compared with the counts in those treated with vancomycin and imipenem-cilastatin (P < 0.001). These results indicate that BO-3482-cilastatin is as effective as vancomycin in murine systemic infections and is more bactericidal than vancomycin in local-tissue infections. The potent in vivo activity of BO-3482-cilastatin against such MRSA infections can be ascribed to the good in vitro anti-MRSA activity and improved pharmacokinetics in mice when BO-3482 is combined with cilastatin and to the bactericidal nature of the carbapenem.

慢性よう疹よりＭＲＳＡ敗血症を発症し，外用剤（３％酢酸を含有する吉草酸ジフルコルトロン軟膏）治療により改善した後期高齢者の１例

An 80-year-old woman being treated with anti-hypertensive drugs developed eruption and itching of the skin. High fever and lymph node enlargement subsequently developed in spite of discontinuing all antihypertensive drugs, and she was admitted to our hospital. At the initial examination, multiple papules were noted over the entire body, and the skin showed thickening and lichenification with scratch marks. There was also generalized enlargement of the superficial lymph nodes. From these findings, her condition was diagnosed as chronic prurigo due to drug allergy. Laboratory tests showed inflammatory findings, anemia and a high serum level of IgE. Analysis of the surface marker of peripheral lymphocytes revealed no abnormalities. Bacteriologic cultures of blood revealed methicillin-resistant Staphylococcus aureus (MRSA). Histologic examination of the lymph nodes revealed chronic reactive lymphadenitis with a follicular pattern. She was strongly suspected of having MRSA septicemia, and so combination chemotherapy with vancomycin, minocycline and cefoperazone/sulbactam was started. However, 1 month after initiation of chemotherapy, the low-grade fever, eruption and moderate inflammatory findings persisted, and culture of the eruptions revealed MRSA. The prurigo was therefore considered to be the source of the septicemia, and daily application of diflucortolone ointment containing 3% acetic acid was started. Thereafter, the clinical and laboratory findings showed a rapid improvement. MRSA infections usually occur in compromised patients who are receiving antibiotics during prolonged hospitalization. The present case, who did not have any underlying disease, indicates that old-age is also an important factor for the development of MRSA septicemia.

Food-initiated outbreak of methicillin-resistant Staphylococcus aureus analyzed by pheno- and genotyping.

An outbreak of methicillin-resistant Staphylococcus aureus (MRSA) involving 27 patients and 14 health-care workers (HCW) was studied. The outbreak started in the hematology unit of the University Hospital Rotterdam, Dijkzigt, The Netherlands, and spread to the surgical unit. Twenty-one patients (77.8%) developed clinical disease, and five died. Subsequently, MRSA was detected in food and in the throat of one of the HCW who prepared food for hematology patients. Food contaminated by an HCW most likely caused the first case of MRSA septicemia. This route of transmission has not been described before. The outbreak strain was probably transmitted to the surgical unit by a colonized nurse, where it caused an explosive outbreak. Airborne probably transmitted to the surgical unit by a colonized nurse, where it caused an explosive outbreak. Airborne MRSA transmission played an important role in disseminating the organism. The outbreak was controlled within 6 months by intensifying surveillance, temporarily closing the affected wards, treating carriers, and instituting an MRSA ward outside the hospital. Phage typing, insertion sequence probing, protein A gene typing, and DNA fingerprinting by PCR revealed that all outbreak-related isolates were identical. By pulsed-field gel electrophoresis, all but one of the outbreak-related isolates were determined to be identical. Protein A gene typing identified numerous (11) repeat units in all outbreak-related isolates, which supports the suggestion that the outbreak strain may have been more virulent and more transmissible than other MRSA strains. Pheno- and genotyping studies underlined the value of DNA fingerprinting methods for investigation of MRSA epidemiology. Optimal discriminatory power was achieved by combining the results of four genotyping methods.

Antimicrobial chemotherapy of septicemia due to methicillin-resistant Staphylococcus aureus.

The outcome of treatment of 48 episodes of septicemia due to methicillin-resistant Staphylococcus aureus (MRSA) in 44 patients was assessed. Twenty-six of the patients died; nineteen of them died of infection, and infection was a major contributing factor to the deaths of the remaining seven patients. Fourteen of fifteen patients treated with inadequate antibiotic therapy died, and the other patient developed a mycotic aneurysm of the femoral artery, for which amputation was necessary. Eight of eleven patients treated with amikacin (alone or combined with another antimicrobial) died, and three recovered slowly; only one recovered fully without sequelae. In an additional two patients who failed to respond to amikacin, treatment was changed to vancomycin. Vancomycin was used to treat 18 episodes of MRSA septicemia in 17 patients. In 14 of these episodes the patients recovered fully. One patient died of uncontrolled infection, and in three, infection was a contributing factor but not the major cause of death. Vancomycin was confirmed as antibiotic of choice in treating MRSA septicemia.