448 isolates of methicillin-resistant Staphylococcus aureus (MRSA) from clinical specimens of patients from the University Hospital, Kuala Lumpur, were phage-typed. These included 35 strains causing two separate outbreaks of infection, one in surgical Ward 6B and another in the Special Care Nursery (SCN). Antibiograms of these outbreak strains in Ward 6B and SCN were entirely different. Phage-typing revealed that 72% of the MRSA isolates were typable. They were typed entirely by Group III phages, the majority (76%) of which were phage type 85. There was only one isolate in SCN which was typed by Group I (phage 80) and Group III phages. None were typed by phages 94, 95, 96 and Group II phages. 14.6% of the typable isolates gave the long pattern reaction of the phage 6/47/54/75/77/83A/84/85 complex. The majority of the outbreak strains in Ward 6B were of phage type 85, whereas those in the SCN were all of the 6/47/54/75/77/83A/84 phage pattern with the exception of one isolate which was also typed by phage 80, a Group I phage.
Methicillin-resistant Staphylococcus aureus has emerged as an important cause of nosocomial infections in recent years. During 1988 in the Department of Surgery of the University Hospital in Kuala Lumpur, Malaysia, 148 patients were shown to be infected or colonized with these organisms. The patients at risk were those who stay in hospital for greater than 14 days, those over 50 years of age, patients who underwent neurosurgery, cardiothoracic surgery, or were admitted with major burns. Of the 148 patients, 78 (52.7%) were clinically infected, the remaining 70 being colonized. A total of 28 patients died (18.9%) but only five (3.4%) as a direct result of this infection. The estimated annual cost of controlling the organism was found to be approximately MR$250,000. (50,000 pounds). This nosocomial infection therefore represents a serious problem, especially in developing countries where health funding and health facilities are limited.
Twenty-one isolates of methicillin-resistant Staphylococcus aureus (MRSA) from Malaysia (M-MRSA) derived from various sources associated with nosocomial infections were phage-typed and compared with 54 international isolates associated with epidemic and sporadic episodes of infections. It appeared that the majority of M-MRSA were non-typable by the international basic set of phages. Two (9.5%) were typed by phage 85. Phage-typing of MRSA revealed that the strains were almost completely restricted to phage groups III and a lesser portion to phage groups I and III.
Methicillin-resistant Staphylococcus aureus (MRSA) as a hospital pathogen has presented many clinical problems in the University Hospital, Kuala Lumpur, Malaysia since 1978. The need for control of spread of these organisms became evident by 1985 when it was noted that the incidence of MRSA among S. aureus isolated from hospital inpatients had increased from 11.5% in 1979 to 18.8% in 1985. The characteristics of 50 MRSA isolates associated with nosocomial infections in the hospital are described here. The predominant strains produced Type IV coagulase and 84% of isolates studied showed moderate to high resistance to methicillin with MIC values of 25 mg l-1 or higher. All the MRSA isolates that could be phagetyped were susceptible to Group III phages, with 76.6% of the isolates being susceptible to phage 85. At least 10 different patterns were distinguishable by plasmid typing, the majority of isolates harbouring up to four small plasmids.
Between August 1990 to November 1991, 905 of 2583 (35.4%) isolates of Staphylococcus aureus were found to be methicillin-resistant in a general hospital in Malaysia. A detailed study of 539 of these isolates showed a high prevalence of methicillin resistant Staphylococcus aureus (MRSA) in the surgical/orthopaedic wards, paediatric wards and the special care unit. The yield of MRSA was highest from wounds/ulcers/skin swabs accounting for 64.2 per cent followed by 6.9 per cent in blood cultures. Vancomycin remains the drug of choice with no resistance detected. The resistance to ciprofloxacin was 6.7 per cent, rifampicin 4.5 per cent and fusidic acid 2.0 per cent. Most isolates were resistant to aminoglycosides. In view of the high prevalence of MRSA in this hospital, the authorities must introduce more effective measures to control its spread as a nosocomial pathogen. Otherwise it may seriously disrupt the efficient delivery of health care services in the country.
Methicillin resistant Staphylococcus aureus (MRSA) is a major infection control problem in many countries. There have been many reports of outbreaks in neonatal nurseries including, in our part of the world, Australia, Hong Kong and Malaysia. A recent outbreak of MRSA in the neonatal intensive care unit in the Kandang Kerbau Hospital, Singapore, presented us with the opportunity to study the clinical characteristics of the outbreak and the effects of infection control measures. Neonates admitted to the neonatal intensive care unit were studied over a 20-month period. They were all screened for nasal colonisation on admission and weekly thereafter. Infections were documented. Over this period there were altogether 2,576 admissions of which 85 infants had nasal colonisation with MRSA (3.3%) and 28 developed infections (1%). Although the majority of infants colonised by MRSA suffered no ill effects, 3 had septicaemia and 2 had septicaemia with osteomyelitis. There were no deaths. Standard infection control measures with barrier nursing and the use of mupirocin nasal ointment were ineffective, and control was achieved only after strict cohorting together with the use of mupirocin was instituted. This was done without additional costs to the department and without additional nurses or doctors.
Methicillin-resistant Staphylococcus aureus (MRSA) infection has been endemic in the University Hospital, Kuala Lumpur since the late 1970s. Fifty isolates of MRSA obtained from clinical specimens of patients with nosocomial infections associated with this organism have been studied by pulsed-field gel electrophoresis (PFGE) of its chromosomal DNA fragments to discrimate between strains and to identify the predominant strain. Twenty-one chromosomal patterns were observed which could be further grouped into nine types. The predominant strain was Type 9-b (40% of isolates) found mainly in the Orthopaedic and Surgical Units. Outbreak strains found in the Special Care Nursery were of Type 1, entirely different from those of the surgical ward S2, which were of Type 9-b. Type 8 strains were found mainly at one end of the hospital building where the maternity, paediatric and orthopaedic units were situated. Genomic DNA fingerprinting by PFGE is recommended as a useful and effective tool for the purpose of epidemiological studies of MSRA infections, particularly for nosocomial infections.
Pyomyositis, purportedly a common tropical infection affecting mainly healthy adults and children, appears to be most uncommon in this region. We report a case of pyomyositis caused by a Methicillin-resistant Staphylococcus aureus (MRSA) in a previously healthy army officer. This case serves to illustrate the difficulty in recognising this disease entity, which is why many cases may have been missed. With the increasing incidence of MRSA nosocomial infections, the emergence of MRSA in a hitherto community-acquired infection poses a major concern especially since intravenous drug abuse and acquired immune deficiency syndrome (AIDS) are on the rise in our country. We hope to inculcate greater awareness of this infection.
Neonatal septic arthritis has always been considered as separate from its counterpart in older children. The condition is uncommon but serious. Affected neonates usually survive, but with permanent skeletal deformities. Ten cases of neonatal septic arthritis were diagnosed between January 1989 and December 1993 in the neonatal intensive care units of two referral hospitals in the state of Kelantan, Malaysia. All except one neonate was born prematurely. The mean age of presentation was 15.6 days. Joint swelling (10/10), increased warmth (7/10) and erythema of the overlying skin (7/10) were the common presenting signs. Vague constitutional symptoms preceded the definitive signs of septic arthritis in all cases. The total white cell counts were raised with shift to the left. The knee (60%) was not commonly affected, followed by the hip (13%) and ankle (13%). Three neonates had multiple joint involvement. Coexistence of arthritis with osteomyelitis was observed in seven neonates. The commonest organism isolated was methicillin resistant Staphylococcus aureus (9/10). Needle aspiration was performed in nine neonates and one had incision with drainage. Follow up data was available for five neonates and two of these had skeletal morbidity. Early diagnosis by frequent examination of the joints, prompt treatment and control of nosocomial infection are important for management.
Between July and December 1994, 25 patients with MRSA bacteraemia were treated at the Hospital Kuala Lumpur, a tertiary hospital in Malaysia with 3000 beds. The patients included 15 males and 10 females whose mean age was 46.7 years (range 13-75). The sources of their MRSA were: Urology/Nephrology, 11; General ICU, six; Orthopaedic, four; Medicine, three; Surgery, one. Their underlying diseases were: end-stage and chronic renal failure, 11; burns, three; acute necrotising pancreatitis, two; haematological malignancies, two; and one each of fracture of the neck of the femur, pustular psoriasis, alcoholic cirrhosis, liver abscess, peptic ulcer (antrectomy), choledochol cyst, and abdominal aneurysm with gangrene of the legs. Six patients were also diabetic. A total of 19 infections were considered nosocomial. The duration of hospital stay ranged from one to 60 days, mean 16 days. On the day of blood culture, 20 patients (80%) were febrile and 15(60%) had leucocytosis. A total of 14 patients were considered to have received prolonged broad-spectrum antibiotics before the bacteraemia; of these, 11 had had either a third-generation cephalosporin and/or a quinolone. The primary foci of infection were: vascular access dialysis catheters, six; infected AV fistulae, three; non-surgical wounds, five; orthopaedic pin, one; multiple venous lines and catheters, nine; unknown, one. The sensitivities to anti-MRSA antibiotics were: vancomycin, 100%; fusidic acid, 96%; rifampicin, 96%; ciprofloxacin and perfloxacin 28% each. In all, 13 patients (52%) eventually died; nine of these deaths were directly attributed to MRSA bacteraemia. The microbiological eradication rate was 88%. Mortality was significantly associated with duration of hospital stay and failure to remove the infected catheters/peripheral lines after the development of MRSA bacteraemia.
We have previously reported the phenotypic characterization of methicillin-resistant Staphylococcus aureus (MRSA) clinical strains isolated in Malaya University Hospital in the period 1987 to 1989 using antibiogram, coagulase typing, plasmid profiles, and phage typing. Here, we report the analysis of the same strains with three genotyping methods; ribotyping, pulsed-field gel electrophoresis (PFGE) typing, and IS431 typing (a restriction enzyme fragment length polymorphism analysis using an IS431 probe). Ribotyping could discriminate 46 clinical MRSA strains into 5 ribotypes, PFGE typing into 22 types, and IS431 typing into 15 types. Since the differences of the three genotyping patterns from strain to strain were quite independent from one another, the combined use of the three genotyping methods could discriminate 46 strains into 39 genotypes. Thus, the powerful discriminatory ability of the combination was demonstrated.
Isolates of 390 Staphylococcus aureus were tested against 13 different antibiotics by a disc diffusion method as recommended by the National Committee for Clinical Laboratory Standards (NCCLS). Strains were isolated from blood (5.7%), cerebrospinal fluid (0.5%), respiratory tract (11.8%), pus and wound (73.3%), urine (1.8%), genital specimens (1.0%) and other specimens (4.3%). Only 4.6% of the isolates were fully susceptible to all the drugs tested. Resistance to penicillin was 94.1%, methicillin, 39.7%, chloramphenicol, 8.5%, ciprofloxacin, 29.2%, clindamycin, 2.1%, erythromycin, 45.9% gentamicin, 40.5%; rifampicin, 3.3% tetracycline, 47.2%, co-trimoxazole, 38.5%, mupirocin, 2.8%, fusidic acid, 3.6%. None of the isolates was resistant to vancomycin. The susceptibility of methicillin-resistant strains to erythromycin, gentamicin, tetracycline and ciprofloxacin was low, while clindamycin, fusidic acid, mupirocin, and rifampicin remained active.
To determine and compare the pulsed-field gel electrophoresis (PFGE) patterns of endemic MRSA strains in 2 major Malaysian hospitals and to compare the PFGE patterns with antibiotypes of the strains studied.
Four hundred methicillin-resistant Staphylococcus aureus strains (MRSA) from different geographical areas in Malaysia were tested for mupirocin susceptibility using minimum inhibitory concentration (MIC) determination. The majority of these strains (98.75%) were susceptible to mupirocin with MICs of < or = 4 mg/l. Fifty-percent of these strains had MICs of 0.125 mg/l or less while 90% of the strains had MICs of 1 mg/l or less. Mupirocin resistance was detected in five strains (1.25%) and one of these (0.25%) had an MIC of 64 mg/l and the other four strains (1%), high-level resistance with MICs > 512 mg/l. Even though the rate of mupirocin resistance in MRSA is still low in Malaysia, its presence calls for a strict policy on mupirocin usage in Malaysian hospitals.
Methicillin-resistant Staphylococcus aureus (MRSA) has been prevalent in our hospital over the last three years. Differentiation among MRSA strains by DNA typing in addition to antibiotic resistance pattern surveillance is crucial in order to implement infection control measures. The aim of this study was to characterize MRSA isolates from patients admitted to Hospital Universiti Kebangsaan Malaysia (HUKM) by phenotypic (analyses of antibiotic susceptibility pattern) and genotypic (PFGE) techniques to determine the genetic relatedness of the MRSA involved and to identify endemic clonal profiles of MRSA circulating in HUKM. Seventy one MRSA strains collected between January to March 2000 from patients from various wards in HUKM were tested for antimicrobial resistance and typed by pulsed-field gel electrophoresis (PFGE). Four major types of PFGE patterns were identified (A, B, C and D) among MRSA strains. Two predominant PFGE types were recognised, Type A (59.2%) and Type B (33.8%). Most of these strains were isolated from ICU, Surgical wards and Medical wards. MRSA strains with different PFGE patterns appeared to be widespread among wards. Strains with the same antibiotype could be of different PFGE types. Most of isolates were resistant to ciprofloxacin, erythromycin, gentamicin and penicillin. One isolate with a unique PFGE pattern Type D and susceptible to gentamicin was identified as a different clone. Some isolates obtained from the same patient showed different PFGE subtypes suggesting that these patients were infected/colonized with multiple MRSA strains. PFGE analysis suggests that MRSA strains with different PFGE types was propagated within our hospital. The relationship between antibiotic susceptibility and PFGE patterns was independent. The ability of PFGE technique in differentiating our MRSA strains make it a method of choice for investigating the source, transmission and spread of nosocomial MRSA infection, and thus an appropriate control programme can be implemented to prevent the spread of MRSA infection.
Two new resveratrol tetramers, hopeaphenol A (1) and isohopeaphenol A (2), along with the known vaticaphenol A (3), were isolated from the stem bark of Vatica oblongifolia ssp. oblongifolia through bioassay-guided fractionation. The structures and their relative stereochemistry were determined by spectroscopic techniques. Compounds 1 and 3 demonstrated moderate activity against methicillin-resistant Staphylococcus aureus and Mycobacterium smegmatis.
The emergence and spread of multiresistant methicillin-resistant Staphylococcus aureus (MRSA) strains, especially those resistant to fusidic acid and rifampicin, in Malaysian hospitals is of concern. In this study DNA fingerprinting by PFGE was performed on fusidic acid- and rifampicin-resistant isolates from Malaysian hospitals to determine the genetic relatedness of these isolates and their relationship with the endemic MRSA strains. In all, 32 of 640 MRSA isolates from 9 Malaysian hospitals were resistant to fusidic acid and rifampicin. Seven PFGE types (A, ZC, ZI, ZJ, ZK, ZL and ZM) were observed. The commonest type was type ZC, seen in 72% of isolates followed by type A, seen in 13%. Each of the other types (ZI, ZJ, ZK, ZL and ZM) was observed in a single isolate. Each type, even the commonest, was found in only one hospital. This suggests that the resistant strains had arisen from individual MRSA strains in each hospital and not as a result of the transmission of a common clone.
This study was conducted to determine the molecular epidemiology of methicillin-resistant Staphylococcus aureus (MRSA) in Malaysian hospitals. A total of 264 MRSA isolates from eight hospitals were subjected to typing by pulsed-field gel electrophoresis (PFGE) of SmaI restricted DNA. Antibiotic disk susceptibility testing was also carried out to determine their resistance patterns. Thirty-one PFGE pattern types were identified. Three major pattern types A, ZC and K were found with type A the predominant profile in c. 80% of strains and present in all hospitals. Unlike type A, other DNA pattern types were unique to the hospitals in which they were isolated. PFGE type A also consisted of strains that were multiply antibiotic resistant. The presence of a single predominant PFGE type in Malaysian hospitals is an important finding which suggests that inter-hospital spread of MRSA had occurred frequently and regularly.
A new method for estimating the time to colonization of Methicillin-resistant Staphylococcus Aureus (MRSA) patients is developed in this paper. The time to colonization of MRSA is modelled using a Bayesian smoothing approach for the hazard function. There are two prior models discussed in this paper: the first difference prior and the second difference prior. The second difference prior model gives smoother estimates of the hazard functions and, when applied to data from an intensive care unit (ICU), clearly shows increasing hazard up to day 13, then a decreasing hazard. The results clearly demonstrate that the hazard is not constant and provide a useful quantification of the effect of length of stay on the risk of MRSA colonization which provides useful insight.
The objective of this study was to find the prevalence of Staphylococcus spp. carriage among hospital personnel and hospital environment and their antibiogram with special emphasis on methicillin resistance. A total of 205 samples from hospital personnel and environment were collected from casualty, oncology and multidisciplinary cardiac unit ward of Kasturba Medical College Hospital, Manipal. Samples were collected using sterile cotton wool swabs and inoculated into brain heart infusion broth. Subcultures were done onto blood agar and MacConkey's agar. Isolates were identified by standard methods up to species level. Antimicrobial susceptibility test was performed according to standardized disc diffusion Kirby-Bauer method. Each of the isolates was screened for methicillin resistance using oxacillin disc on Mueller Hinton agar plate followed by MIC for methicillin and cefoxitin susceptibility test by disc diffusion method. Sixty five out of 205 strains (31.7%) were Staphylococcus spp. and all of them were coagulase negative. Most of the strains belonged to S.epidermidis 49.23% (32/65) followed by S. saprophyticus 26.15% (17/65). Maximum isolates of S.epidermidis were from anterior nares 28.12% (9/32 strains of S.epidermidis). Highest number of methicillin resistant coagulase negative strains (3/9, 33.33%) were isolated from stethoscope of multidisciplinary cardiac unit ward followed by carriers in the anterior nares (2/9, 22.22%). Methicillin resistant coagulase negative staphylococci are prevalent in anterior nares of hospital personnel and in the hospital environment thereby providing a definite source for hospital acquired infection. All isolates were sensitive to vancomycin, ciprofloxacin and amikacin.