Displaying publications 21 - 40 of 50 in total

Abstract:
Sort:
  1. Ngeow YF, Ramachandran S, Cheong YM
    Sex Transm Dis, 1991 7 1;18(3):192-4.
    PMID: 1948519
    Between January and August, 1989, 36 men and 28 women with uncomplicated lower genital tract infections by Neisseria gonorrhoeae were given single intramuscular injections of sulbactam (500 mg)/ampicillin (1000 mg) together with 1 g oral probenecid. Cure rates that were obtained were 100% for women, 97.2% for men, 100% for patients with penicillinase-producing Neisseria gonorrhoeae (PPNG), and 98.4% for patients with non-PPNG. No serious side effects were encountered, and patient acceptance of the drug was good. A high proportion of patients had concurrent chlamydial infection. Sulbactam/ampicillin was found to be effective against gonococcal urethritis and cervicitis by both PPNG and non-PPNG but have little effect on concomitant chlamydial infections, especially in women.
  2. Naidu BR, Ngeow YF, Pang T
    Eur J Epidemiol, 2003;18(2):135-7.
    PMID: 12733835
    Chlamydophila pneumoniae, an important respiratory pathogen causing lower respiratory tract infections, has also been implicated in coronary heart disease (CHD). This study reports a cross-sectional, demographic, serological analysis of the prevalence of Chlamydophila pneumoniae antibodies in a multiracial Malaysian population. Generally, Malaysian Indians had the highest degree of seropositivity (58%) followed by the Chinese (54%) and the Malays (32%), results which were statistically significant (CI: 95%; p < 0.01). Interestingly, this trend was also reflected in the study group consisting of patients with acute myocardial infarctions (AMI) and chronic CHD. Again, the Indians were more frequently seropositive (65%), with more than 50% having IgG titres > or = 128. Comparatively, the Chinese and Malays showed 51 and 17% seropositivity respectively. These results were also statistically significant (CI: 95%; p < 0.01). Malaysian Indians are more commonly afflicted with CHD. A variety of factors have been suggested to explain this prevalence including diet, social habits, genetics and the possible role of infectious agents. This study notes an interesting association between this pattern of racial prevalence and the possible role of C. pneumoniae infections as a contributory/predisposing factor in the development of cardiovascular disease.
  3. Raja NS, Karunakaran R, Ngeow YF, Awang R
    J Med Microbiol, 2005 Sep;54(Pt 9):901-903.
    PMID: 16091445 DOI: 10.1099/jmm.0.46169-0
    Vancomycin-resistant enterococci (VRE) are formidable organisms renowned for their ability to cause infections with limited treatment options and their potential for transferring resistance genes to other Gram-positive bacteria. Usually associated with nosocomial infections, VRE are rarely reported as a cause of community-acquired infection. Presented here is a case of community-acquired infection due to vancomycin-resistant Enterococcus faecium. The patient had been applying herbal leaves topically to his cheek to treat a buccal space abscess, resulting in a burn of the overlying skin. From pus aspirated via the skin a pure culture of E. faecium was grown that was resistant to vancomycin with a MIC of >256 microg ml-1 by the E test and resistant to teicoplanin by disc diffusion, consistent with the VanA phenotype. The organism was suspected of contaminating the leaf and infecting the patient via the burnt skin. This case highlights the need for further studies on the community prevalence of VRE among humans and animals to define unrecognized silent reservoirs for VRE, which may pose a threat to public health.
  4. Ngeow YF, Rachagan SP, Ramachandran S
    J Clin Pathol, 1990 May;43(5):400-2.
    PMID: 2196283
    A single antigen indirect immunofluorescence test was used to screen for chlamydial antibody among Malaysian infants, children, sexually active adults and prostitutes. Of 794 serum samples tested, 361 (45.5%) were positive. Seropositivity increased with age and sexual activity and ranged from 10 to 16% among children under 10 years old to 94.4% among prostitutes. Pregnant women and female adolescents showed a higher antibody prevalence than nonpregnant and older women. Six (13%) infants under 6 months of age were positive for chlamydial IgM.
  5. Cheong YM, Wong WK, Ngeow YF
    Singapore Med J, 1993 Aug;34(4):352-3.
    PMID: 8266214
    A first case of Chlamydia pneumoniae pneumonia in Malaysia is reported. The diagnosis was made by a significant change in C. pneumoniae antibody titre. The infection responded well to a course of erythromycin.
  6. Wong YL, Ong CS, Ngeow YF
    J Clin Microbiol, 2012 Sep;50(9):3084-8.
    PMID: 22760048 DOI: 10.1128/JCM.00753-12
    A variable-number tandem-repeat (VNTR) typing assay for the differentiation of Mycobacterium abscessus strains was developed. This assay showed complete reproducibility, locus stability, and a discriminatory power (Hunter-Gaston discriminatory index [HGDI] of 0.9563) that is superior to that of multilocus sequencing. It is a promising tool for the investigation of Mycobacterium abscessus epidemiology and nosocomial outbreaks.
  7. Ngeow YF, Soo-Hoo TS
    Mycoses, 1989 Nov;32(11):563-7.
    PMID: 2615779
    A total of 2,153 high vaginal swabs were processed for the presence of yeasts. The specimens were obtained from pregnant and non-pregnant Malaysian women with and without vaginitis. The yeast species most commonly isolated were Candida albicans, C. glabrata, C. famata and C. parapsilosis. C. albicans was isolated from 27% of pregnant women with vaginitis, 14% of pregnant women with no overt vaginitis, 15% of non-pregnant women with vaginitis, and 3% of non-pregnant women with no vaginitis. The significant difference of the isolation rates from women with and without vaginitis indicates that C. albicans is likely to be a vaginal pathogen.
  8. Wang X, Yap SF, Ngeow YF
    Malays J Pathol, 2024 Aug;46(2):295-298.
    PMID: 39207006
    INTRODUCTION: Candida albicans and Streptococcus mutans co-exist in biofilms in the oral cavity. In this study, the impact of S. mutans on the growth of C. albicans within a mixed-species biofilm was examined.

    MATERIALS AND METHODS: Single species C. albicans biofilms and mixed species biofilms containing C. albicans and S. mutans at 1:3 and 1:10 ratios were constructed in 6-well microtiter plates. After 24 hours of incubation, the density of resuspended biofilm cells was determined as CFU/ml and used to compare the growth of C. albicans in single species and mixed species biofilms.

    RESULTS: The CFU/ml of C. albicans in mixed-species biofilms was found to be higher than that in single-species biofilms.

    CONCLUSION: S. mutans promotes the growth of C. albicans in a co-inhabited biofilm.

  9. Yong SF, Ngeow YF, Tong YK, Ong JT
    Malays J Pathol, 2006 Dec;28(2):79-82.
    PMID: 18376795 MyJurnal
    Male-specific coliphages are often used as indicators of contamination by enteric viruses. These phages can be detected in water samples by plaque assays and by polymerase chain reaction. In this study, the M13 coliphage was used to develop a real-time PCR assay for the detection of male-specific DNA coliphages. The real-time PCR was found to have a reaction efficiency of 1.45 and detection limit of 10(-3) plaque forming units per reaction mix. Repeated amplification and melting curve analyses demonstrated high specificity and reproducibility of the real-time assay. Quantitative detection with the real-time PCR should allow rapid assessment of the level of viral contamination in water.
  10. Ong CH, Asaad M, Lim KC, Ngeow YF
    Malays J Pathol, 2002 Dec;24(2):91-4.
    PMID: 12887166
    Fifty samples of chicken, duck and geese faeces were obtained from 13 wet markets in Kuala Lumpur to study the prevalence of vancomycin-resistant enterococci (VRE) among local market poultry. Biotyping of colonies grown on azide agar incubated at 45 degrees C yielded E. pseudoavium, E. faecalis, E. faecium and E. gallinarum from chicken faeces and E. malodoratus, E. faecalis, E. faecium, E. gallinarum, E. hirae/dispar, and E. durans from goose and duck faeces. On agar containing 6 mg/ l of vancomycin, one strain of E. flavescens was identified, giving a VRE detection rate of 2.0%. This isolate had a vancomycin M.I.C. of 8 mg/l as determined by the Etest, and the van C-3 gene that was identified by PCR followed by sequence analysis. The prevalence of VRE among poultry sold in local markets appears to be low, and may reflect the infrequent use of antimicrobials in our poultry farms. Nevertheless, the possibility of human acquisition of microbes via the food chain cautions against the use of antimicrobials in animal husbandry that may encourage the emergence and spread of multi-drug resistant organisms like the VRE among animal microbial flora.
  11. Ngeow YF, Hema V, Zakaria M, Lee CH, Ramachandran S
    Malays J Pathol, 1997 Dec;19(2):127-32.
    PMID: 10879253
    First-void urine samples collected from sexually transmitted diseases (STD) clinic patients were examined by a nested polymerase chain reaction (PCR) and a commercial enzyme immunoassay (IDEIA Chlamydia) for the diagnosis of Chlamydia trachomatis urethritis or cervicitis. The primers for the PCR amplified a target in the major outer membrane protein (MOMP) gene in C trachomatis while the IDEIA detected genus-specific chlamydial lipopolysaccharide. Discrepant results were resolved by retesting urine specimens with a second (plasmid-based) PCR and taking urethral or endocervical swab results into consideration. For 231 men (chlamydial prevalence 20.4%), the sensitivity, specificity, positive and negative predictive values were 59.6%, 99.5%, 96.6% and 90.6% for urine IDEIA, 68.1%, 99.5%, 97% and 92.4% for urethral swab IDEIA and 97.9%, 99.5%, 97.9% and 99.5% for urine PCR. The corresponding rates for 66 women (chlamydial prevalence 54.6%) were 19.4%, 100%, 100% and 50.8% for urine IDEIA, 86.1%, 96.7%, 96.9% and 85.3% for endocervical swab IDEIA and 91.7%, 93.3%, 94.3% and 90.3% for urine PCR. Hence, in a high prevalence population, the urine IDEIA was a suitable alternative to the male urethral swab IDEIA but significantly less sensitive than the endocervical swab IDEIA. The urine PCR was, however, much more sensitive than the urine IDEIA for both men and women and could replace the endocervical swab IDEIA for the diagnosis of chlamydial cervicitis.
  12. Chan L, Yasmin AH, Ngeow YF, Ong GS
    Med J Malaysia, 1994 Mar;49(1):62-7.
    PMID: 8057993
    A closed enteral delivery system consisting of a cardboard tetrapack containing the sterile ready-to-use liquid feed and an independent sterile administration set, has been devised. We found bacterial contamination within 24 hours in this system in patients on ventilatory support in intensive care. This emphasises the need for meticulous care in handling enteral feeding systems to prevent environmental contamination.
  13. Rajakumar MK, Ngeow YF, Khor BS, Lim KF
    Sex Transm Dis, 1988 1 1;15(1):25-6.
    PMID: 3162781
    Forty-three patients with uncomplicated gonorrhea were treated with 400 mg of ofloxacin. All had cultures negative for Neisseria gonorrhoeae at follow-up within two weeks of treatment. Minimal side effects were reported. Ofloxacin appears to be satisfactory as a single-dose oral drug for the treatment of gonococcal urethritis, including those cases caused by penicillinase-producing strains of N. gonorrhoeae.
  14. Illyaaseen Z, Ngeow YF, Yap SF, Ng HF
    Malays J Pathol, 2021 Apr;43(1):55-61.
    PMID: 33903306
    Candida albicans is an important opportunistic fungal pathogen capable of causing fatal systemic infections in humans. Presently in Malaysia, there is little information available on the genetic diversity of this organism and trends in behavioural characteristics. In this project, three genotyping methods: 25S rDNA genotyping, Alternative Lengthening of Telomerase (ALT) sequence typing and Multi-Locus Sequence Typing (MLST) were applied to study the genetic diversity of strains from infected hospital in-patients and asymptomatic individuals in the community. The results showed that, with the 25S rDNA genotyping, as in other parts of the world, the most common genotype was type A which accounted for approximately 70% of the 111 isolates tested. Further typing with the ALT sequence showed type 3 to be the most common in the isolates tested. MLST analysis revealed many possibly novel sequence types, as well as a statistically significant association between pathogenicity and a group of closely related isolates, most of which were from hospital samples. Further work on genotypes associated with enhanced virulence will help to clarify the value of genotyping for clinical and epidemiological investigations.
  15. Gan CY, Yap SF, Ngeow YF, Wong HC
    Sex Transm Dis, 1991 4 1;18(2):84-8.
    PMID: 1862464 DOI: 10.1097/00007435-199118020-00006
    This study documents the prevalence of Hepatitis B serological markers among STD patients who have had multiple sexual partners in Kuala Lumpur, Malaysia, and compares the rates with those of a sample of the population with single or no sexual partners. A total of 336 Chinese STD patients (multiple partners group) and 234 Chinese control subjects (non-multiple partner group) were screened. Those with a history of blood transfusion or parenteral drug abuse had been excluded from the study, and all study subjects were heterosexuals. The overall carrier rate was 9.2% for the multiple partner group (MP group) and 6.8% for the non-multiple partner group (NMP group). Infection rates were 64.3% for the MP-group and 38.9% for the NMP group. After adjustments for age and sex, there was no significant difference in carrier rates between the two groups, but infection rates were significantly different with the MP group, being 3.2 times more likely to acquire infection than the NMP group. The study concludes that in heterosexuals, those with multiple sexual partners have increased chances of acquiring HBV infection.
  16. Thong KL, Ngeow YF, Altwegg M, Navaratnam P, Pang T
    J Clin Microbiol, 1995 May;33(5):1070-4.
    PMID: 7615707
    A total of 61 isolates of Salmonella enteritidis were analyzed by the techniques of pulsed-field gel electrophoresis (PFGE) and ribotyping. Twenty-three of the isolates were from Zurich, Switzerland, and 38 isolates were from the University Hospital, Kuala Lumpur, Malaysia. Five of the Malaysian isolates were hospital-related outbreak strains and were shown to be indistinguishable by PFGE analysis following digestion with three different restriction endonucleases, XbaI (5'-TCTAGA-3'), SpeI (5'-ACTAGT-3'), and AvrII (5'-CCTAGG-3'). The PFGE pattern of an isolate from a suspected carrier staff nurse was found to be identical to those of the hospital outbreak isolates. These isolates were also indistinguishable by ribotyping with SmaI and SphI. The same single PFGE pattern was also detected in 29 of 32 sporadic isolates of S. enteritidis. Four closely related ribotypes were detected among these 29 isolates. Similarly, outbreak-related strains from Switzerland showed close genetic identity by PFGE and ribotyping. Strains obtained from poultry showed more variations in their PFGE patterns and ribotypes, although the patterns were still closely related. In addition, SphI ribotypes A and D among the Swiss strains correlated with phage types 4 and 8, respectively. No correlation of phage types with PFGE pattern was noted. Both PFGE and ribotyping indicate that the S. enteritidis strains circulating in Malaysia and Switzerland are very similar and may be clonally related. Comparison of the PFGE patterns with the ribotypes for 23 Swiss and 16 Malaysian isolates showed that there was a 69% concordance in the grouping of isolates. We conclude that the close genetic similarity observed between epidemiologically unrelated and outbreak-related isolates of S. enteritidis suggests that both PFGE and ribotyping are of limited value in the epidemiological analysis of these particular isolates, possibly because of the highly clonal nature of pathogenic strains of S. enteritidis.
  17. Chan PW, Lum LC, Ngeow YF, Yasim MY
    PMID: 11556595
    Mycoplasma pneumoniae is increasingly recognized as an important cause of community acquired pneumonia (CAP) in children. We determined the importance of M. pneumoniae as a causative agent in 170 children aged 1 month to 15 years who were hospitalized with CAP over a 6-month period. The diagnosis of M. pneumoniae infection was based on serological evidence obtained by a particle agglutination test (SERODIA-MYCO II). A positive serological diagnosis was made if the acute phase serum titer was more than 1:160 or paired samples taken 2-4 weeks apart showed a four-fold or greater rise in the serum titer. M. pneumoniae was identified as the causative agent in 40 (23.5%) children. Children with M. pneumoniae infection were more likely to be older than 3 years (OR 4.0 95%CI 1.8-9.1, p<0.001), Chinese (OR 4.3 95%CI 2.0-8.9, p<0.001), have a duration of illness longer than 7 days prior to admission (OR 6.0 95%CI 2.7-13.5, p<0.001) and have perihilar interstitial changes on chest X-ray (OR 4.6 95%CI 2.2-9.9, p<0.001). A significant number of hospital admissions for CAP in Malaysian children can be attributed to M. pneumoniae. It is important to identify these children so as to administer the most appropriate antibiotic treatment.
  18. Lim CT, Thong MK, Parasakthi N, Ngeow YF
    Ann Acad Med Singap, 1997 Jul;26(4):421-5.
    PMID: 9395802
    Between January 1984 and December 1994, 30 cases of early neonatal group B streptococcus (GBS) septicaemia were managed in the Neonatal Unit, University Hospital, Kuala Lumpur. Two neonates were outborn and 28 were inborn, giving an average annual incidence of neonatal GBS septicaemia of 0.4/1000 livebirths among inborn babies. In a separate survey over a three-month period, GBS genital carriage rate among 196 parturients was found to be 9.7%. Of the infants with GBS septicaemia, the mean gestational age was 37.5 +/- 3.8 weeks and the mean birthweight was 2540 +/- 716 g. Twelve (40%) were preterm infants and 14 (47%) were low birthweight infants. Male and female infants were almost equally affected. Prolonged rupture of membranes and maternal pyrexia accounted for only 5 (17%) and 3 (10%) of the cases respectively. Twenty-four (80%) neonates had onset of symptoms within 6 hours of life and respiratory symptoms were observed in 24 (80%) of the cases, while meningitis was uncommon. Six (20%) neonates died. Preterm and low birthweight infants had higher mortality than their term counterparts: 42% versus 6% and 36% versus 6% respectively. Of those who died, 4 (67%) required respiratory support right from birth and the mean time of onset of symptoms was 4 hours (range 0 to 21 hours) and the duration of survival was only 28.8 hours (range 12 to 38 hours). As the incidence of neonatal GBS septicaemia was low, mass screening and chemoprophylaxis for GBS were not recommended. All the GBS isolates were sensitive to penicillin and ampicillin, thus one of these antibiotics should be included in the antimicrobial therapy of septic neonates.
  19. Chua KB, Ngeow YF, Lim CT, Ng KB, Chye JK
    Med J Malaysia, 1999 Jun;54(2):242-6.
    PMID: 10972036
    A prospective study was carried out among pregnant women and their newborn babies in the University Hospital, Kuala Lumpur from January 1996 to June 1997. The maternal cervical colonization rates of Ureaplasma urealyticum (UU) and Mycoplasma hominis (MH) were found to be 57.5% and 15.8% respectively while the isolation rates from nasopharyngeal secretions of the newborns were 50.8% for UU and 6.6% for MH. The overall transmission rates were 88.4% for UU and 42.1% for MH. There was no significant difference in the transmission rates of either organism from mothers to their respective newborn babies by the maturity of pregnancy. In preterm babies, the nasopharyngeal isolation rates of UU and MH were not influenced by the babies' gestational age and birth weight nor by the maternal history of abortion or parity. However, there was a tendency for UU to persist in the nasopharyngeal secretion of preterm babies especially those of birth weight below 2 kg. None of the babies contaminated with mycoplasmas at birth developed respiratory symptoms during six to eight weeks of follow-up.
Filters
Contact Us

Please provide feedback to Administrator (afdal@afpm.org.my)

External Links