The content of indole and the pH have been determined post mortem in shrimps (Pandalus borealis) caught in the Barents Sea and in shrimps caught outside Malaysia, India and Taiwan. These two criteria were compared with organoleptic assessment and the contents of volatile nitrogen bases (ammonia, trimethylamine) and living bacteria. For shrimps caught in the Barents Sea, both raw shrimps stored in ice and processed (broiled, peeled and single-frozen) shrimps were investigated. The results showed that only low levels of indole had been formed during ice-storage. Not until an advanced state of spoilage could a distinct increase in the indole content in raw and in boiled, peeled shrimps be discerned. pH increased slowly and varied in the area between acceptable and not acceptable quality. Neither the indole content nor the pH seems therefore to be a useful criterion for quality assessment either of raw shrimps caught in the Barents Sea or of such shrimps after processing (boiling and peeling). Most of the samples of boiled, peeled shrimps from the Far East were assessed organoleptically as less good-spoiled, and bacterial growth was significant. The content of trimethylamine oxide and volatile nitrogen was low, while the content of indole was high and exceeded 25 microgram/100 g in 8 or 14 samples. This is the upper limit for import in USA. The content of indole seems to be an important quality criterion for shrimps caught in warmer countries. The content of indole exceeded 25 microgram/100 g in some samples which were assessed organoleptically as acceptable. The pH was lower in brine-treated shrimps than in the others.
Enterotoxin production by strains of Staphylococcus aureus isolated from human, food and animal sources was investigated. Of the 130 isolates studied, 27 (20.8%) were found to be enterotoxigenic. The most common enterotoxin detected from human sources was enterotoxin C whereas enterotoxin B occurred more frequently in staphylococcal strains of food origin. The 2 enterotoxigenic strains, from animals isolated from a dog and a goat, produced enterotoxins A and C, respectively. Enterotoxin E was not detected alone from any of the enterotoxigenic strains studied, but occurred together with other enterotoxins. The need to detect enterotoxin in staphylococcal strains and in suspected foods for the confirmation of staphylococcal food poisoning is discussed.
Enterotoxin production by strains of Staphylococcus aureus isolated from foods unconnected with outbreaks offood poisoning was investigated. Twenty-three percent of 217 strains examined produced enterotoxins A, B, C, D or E. Enterotoxin C was found to occur most frequently. Enterotoxin A was not detected alone from any of the strains examined, but occurred together with other enterotoxins. The overall number of strains isolated from raw foods which produced one or more enterotoxins was higher than that for cooked foods. Antibiotic sensitivities were unrelated to enterotoxin production and no correlation could be found between methicillin resistance and enterotoxigenicity.
Cultures of Staphylococcus aureus from eight food poisoning incidents in Malaysia were examined for their ability to produce enterotoxins. Five of the eight strains were found to be enterotoxigenic, the enterotoxins detected being A and E (three strains), A and C (one strain), and C (one strain). Penicillinase production was observed in four of the five enterotoxigenic strains; the penicillin·sensitive strain was also found to be coagulase-negative. The bacteriological and epidemiological investigations for confirming staphylococcal food poisoning are presented. The preventive measures to be taken in reducing such outbreaks are emphasized.
Bacterial skin infection was studied in 239 children between the ages of 1 and 12 years in an urban squatter area in Kuala Lumpur over a period of three months (January - March 1983). 62 children presented with dermatological problems, 33 of which were clinically diagnosed as pyoderma. Microbiological examination of swabs from the lesions yielded mixed growth from 54.5% (18/33) specimens. Beta-haemolytic streptococci were isolated from 63.6% (21/33) and Staphylococcus aureus from 54.5% (18/33) specimens. All streptococcal isolates were grouped with a commercial kit, the Streptex (Wellcome). 81% (17/21) belonged to Lancefield's group A, 90% of which were not M or T typable by the standard international set of antisera. Urine analysis, pharyngeal swab culture and determination of anti-streptococcal antibody titre were also performed for children with positive skin cultures for group A streptococcus. 6% (2/33) of children with impetigo developed acute glomerulonephritis, requiring hospitalization.
Study site: Growth and nutrition clinic, squatter area, Kuala Lumpur, Malaysia
55% of a sample of patients in a rural
community, and 76% of a sample of patients and
staff in the local district hospital were found to
be nasal carriers for Staphylococcus aureus. The
in vitro antibiotic susceptibility patterns of 46
strains of S. aureus isolated in nasal carriers as
well as of 43 strains in community-acquired skin
infections were characterised. High levels of
resistance were expressed to penicillin (73%),
cephalexin (64%) and tetracycline (46%).
Resistance to erythromycin (18%) was moderate.
A few strains showed resistance to methicillin
(5 isolates), vancomycin (4), [usidic acid (3),
cotrimoxazole (1), and none to gentamicin.
Penicillin can no longer be recommended for
treating community-acquired S. aureus infections.
Methicillin resistant Siaphylococcus aureus Is a common isolate from clinical specimens obtained from babies at the special care nursery of the Kuala Lumpur Maternity Hospital. Major Infections due to this organism were, however uncommon and the organism had in the majority of cases been present as a coloniser or as a cause of superficial infection. Netilmicin is a valuable antibiotic in the treatment of the severe infections.
Staphylococcal infection is common in Malaysian hospitals. A recent survey of 22 Malaysian hospitals revealed that staphylococci were isolated from almost 40% of positive blood cultures. A more detailed analysis of such cases in our own hospital showed that almost 70% of Staphylococcus aureus and about 16% of coagulase-negative staphylococcal isolates were associated with clinically-significant disease. Staphylococcal bacteraemia was seen mainly in neonatal sepsis, skin and soft tissue infections, pneumonia, arthritis, osteomyelitis, endocarditis and postoperative sepsis. Multiply-resistant S. aureus were encountered in all the hospitals surveyed. Resistance rates to penicillin ranged from 40% to almost 100% while methicillin resistance rates of up to 25% were reported from several hospitals.
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.
Forty cases of cerebral abscesses were studied prospectively to establish the microbial agents implicated in these cases. Chronic otitis media (14 patients, 35%), congenital heart disease (five patients, 12.5%),a and meningitis (five patients, 12.5%) were among the important predisposing factors. Streptococcus (14 patients, 35%) was the most common causative pre-isolated, the predominant species being Streptococcus milleri (11 patients, 27.5%). Other organisms isolated included Proteus mirabilis in six patients (15%) and Staphylococcus aureus in five patients (12.5%). Anaerobes (12 patients, 30%), predominantly Bacteroides sp. (eight patients, 20%), played an important role in these cases, the majority of which were isolated in mixed cultures. Gas-liquid chromatographic analysis of pus detected the presence of anaerobes in another 11 cases of cerebral abscess, in which cultures of anaerobes were negative. Therefore, gas-liquid chromotography is useful as an adjunct to conventional bacteriological methods in providing a rapid and sensitive means of detecting anaerobes in pus obtained especially from patients who had received antibiotic therapy prior to hospitalization.
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.
Cefepime is a new cephalosporin antibiotic which is highly active against both Gram-positive and Gram-negative organisms. The purpose of this study was to establish the in-vitro activity of cefepime and three other cephalosporins against recent clinical isolates from patients at the General Hospital Kuala Lumpur. A total of 334 strains comprising Enterobacteriaceae, non-fermentative Gram-negative bacilli and Staphylococcus aureus were tested for their sensitivity to cefepime, cefotaxime, ceftriaxone and ceftazidime. Minimum inhibitory concentrations of the antibiotics were established using an agar dilution method. With the exception of some strains of Flavobacterium meningosepticum, Xanthomonas maltophilia and other non-fermentative Gram-negative bacilli, cefepime was found to be active against a wide range of Gram-negative organisms. Cefepime was as or more active than the other cephalosporins against Acinetobacter, Enterobacteriaceae and methicillin-sensitive Staphylococcus aureus. Strains of Klebsiella and Salmonella that were resistant to the third generation cephalosporins were sensitive to cefepime. Cefepime could be a valuable alternative for the treatment of nosocomial infections due to multiply resistant organisms.
An outbreak of Methicillin Resistant Staphylococcus aureus (MRSA) in the Neonatal Intensive Care Unit (NICU), Seremban Hospital is reported. The pattern of colonisation and infection with the MRSA was studied for the 1 year period between May 1987 till April 1988. There were few serious MRSA infections. The majority of patients were either colonised or superficially infected. The organism was resistant to all Penicillins, Gentamicin and most Cephalosporins. Netilmicin and Amikacin have shown good activity against MRSA.
Recurrent boils are troublesome enough to children and their parents to be finally referred to the paediatricians. This study attempts to provide local data on epidemiology, pattern of infections of offending organism especially Staphylococcus aureus and underlying immunological abnormality. This condition does not appear to be related to socio economic status nor is staphylococcal nasal cariage a direct contributing factor. Defect in neutrophil function especially the respiratory burst assayed via chemiluminescence response to Staphylococcus aureus is closely associated with this condition. It is hoped that this data would be a further impetus for further research into this exciting field.
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.