MyMedR

Fulltext In vitro activity of fluconazole and voriconazole against clinical isolates of Candida spp. by E-test method

Madhavan P, Jamal F, Chong PP, Ng KP

Trop Biomed, 2010 Aug;27(2):200-7.

PMID: 20962716 MyJurnal

The in vitro susceptibility of clinical Candida isolates towards fluconazole and voriconazole was determined using the E-test method. A total of 41 clinical isolates recovered from patients since 2004 until 2009 from two local hospitals in Kuala Lumpur, Malaysia were used. These comprised Candida tropicalis, Candida albicans, Candida krusei, Candida parapsilosis, Candida rugosa, Candida dubliniensis and Candida glabrata. Strains from American Type Culture Collection were used as quality control. Lawn cultures of the isolates on RPMI-1640 agar medium supplemented with 2% glucose were incubated with the E-test strips at 35ºC for 48 h. Our results show that 71% were susceptible to fluconazole and 90% were susceptible to voriconazole. All strains of C. krusei were resistant to fluconazole and 50% were susceptible in a dose-dependent manner to voriconazole. There were 66% and 33% of C. glabrata that were resistant to fluconazole and voriconazole. Our study revealed that majority of the clinical Candida isolates was susceptible to fluconazole and voriconazole with a small percentage being resistant to both the drugs.

Trends in obstetric anaesthesia and analgesia over a ten year period in the University Malaya Medical Centre, Kuala Lumpur

Chan YK, Ng KP, Chiu CL

Int J Obstet Anesth, 2002 Jul;11(3):176-9.

PMID: 15321544 DOI: 10.1054/ijoa.2002.0954

Available data for obstetric care in the University Malaya Medical Centre, Kuala Lumpur from 1987 to 1999 were reviewed. Despite incomplete data, we were able to determine fairly well the practice of obstetric anaesthesia and analgesia in the unit, and the changes over the years. There was a decline in the use of general anaesthesia for both elective and emergency caesarean sections from 41.3% and 69.4% respectively in 1995 to 21.6% and 26.9% respectively in 1999. By 1999, regional anaesthesia had become the most common method of anaesthesia administered in both elective (14.3% epidural and 63.5% spinal) and emergency (30.2% epidural and 42.6% spinal) caesarean sections. The percentage of patients delivering vaginally who received epidural analgesia appeared to have stabilised at about 8 to 9% in the last few years, with a gradual decline in the total instrumental delivery rate from a high of about 12% to the pre-epidural rate of 7%.

Meningitis Caused by Rhodotorula mucilaginosa in HIV-Infected Patient: A Case Report and Review of the Literature

Mohd Nor F, Tan LH, Na SL, Ng KP

Mycopathologia, 2015 Aug;180(1-2):95-8.

PMID: 25739670 DOI: 10.1007/s11046-015-9879-0

Rhodotorula species are increasingly being identified as a cause of fungal infection in the central nervous system, especially in patients with compromised immunity. The diagnosis could easily be missed due to low index of suspicion, as cryptococcus meningitis and cerebral toxoplasmosis are more common amongst immunocompromised hosts. To date, there are six cases of Rhodotorula-related meningitis reported, and three are associated with human immunodeficiency virus infection. In this report, a case of a Malaysian male with underlying human immunodeficiency virus infection who developed Rhodotorula mucilaginosa meningitis is presented. High-grade fever and severe headaches were the complaints presented in three previous case reports. India ink and nigrosin stainings were performed in the two previous reports and both revealed positive results. R. mucilaginosa were isolated from the culture of the patient's cerebrospinal fluid in all three previous reports. Predominant lymphocyte infiltration in the cerebrospinal fluid examination was documented in two reports. CD4 counts were above 100/µl in two previously published reports, while another report documented CD4 count as 56/µl. Amphotericin B and itraconazole are identified to be the first line of antifungal used and as the maintenance therapy, respectively. The possibility of relapse cannot be excluded as it was reported in the first report. It was also revealed that the current case has almost similar clinical presentation and therapeutic outcome as compared to the published reports, but some differences in diagnostic details were to be highlighted.

Fulltext Fusarium sp. infection in a patient with acute lymphoblastic leukaemia

Tan R, Ng KP, Gan GG, Na SL

Med J Malaysia, 2013 Dec;68(6):479-80.

PMID: 24632920 MyJurnal

In the past two decades, Fusarium species have been increasingly recognized as serious pathogens in immunocompromised patients. The outcome of fusariosis in the context of severe persistent neutropaenia has been almost universally fatal. The treatment of fusariosis in immunocompromised patients remains a challenge and the prognosis of systemic fusariosis in this population remains poor. This report presents a case of fatal fusariosis in a 37- year-old patient who was diagnosed with precursor-B cell Acute Lymphoblastic Leukaemia (ALL).

Fulltext Identification of Mycobacterium species following growth detection with the BACTEC MGIT 960 system by DNA line probe assay

Ng KP, Rukumani DV, Chong J, Kaur H

Int J Mycobacteriol, 2014 Jun;3(2):82-7.

PMID: 26786328 DOI: 10.1016/j.ijmyco.2014.03.005

The tuberculosis and infections caused by nontuberculous mycobacterial (NTM) species are increasing in patients presented with respiratory illness, and it is crucial to document the epidemiology of these infections.

Mycobacterium brisbanense species nova isolated from a patient with chronic cavitary lung infection

Poh ME, Liam CK, Ng KP, Tan R

Chest, 2014 Apr;145(4):858-860.

PMID: 24687707 DOI: 10.1378/chest.13-1952

We describe the first case, to our knowledge, of Mycobacterium brisbanense species nova with the type strain W6743T (=ATCC 49938T=DSM 44680T) isolated from the lungs of a man with a 6-month history of productive cough and intermittent fever presenting with acute hypoglycemia. A CT scan of the thorax revealed multiple small nodules and consolidation over both lungs with cavitation. Sputum culture repeatedly grew M brisbanense species nova, a novel species never before isolated in Malaysia. The case met the American Thoracic Society criteria for the diagnosis of nontuberculous mycobacterial infection. There was dramatic clinical and radiologic response to treatment with an empirical combination of rifampicin, ethambutol, and levofloxacin and subsequently clarithromycin and levofloxacin once sensitivity was known. This report is the first, to our knowledge, of the pathogen isolated in a patient with chronic cavitary lung infection since it was first identified from an antral sinus in Brisbane, Queensland, Australia, and the first time it is isolated from a human subject in Malaysia.

Detection of 10 medically important Candida species by seminested polymerase chain reaction

Than LT, Chong PP, Ng KP, Seow HF

Diagn Microbiol Infect Dis, 2012 Feb;72(2):196-8.

PMID: 22154674 DOI: 10.1016/j.diagmicrobio.2011.10.008

A seminested PCR detecting ten medically important Candida species were achieved. Analytical sensitivity and specificity were not compromised.

Etiology of blood culture isolates among patients in a multidisciplinary teaching hospital in Kuala Lumpur

Karunakaran R, Raja NS, Ng KP, Navaratnam P

J Microbiol Immunol Infect, 2007 Oct;40(5):432-7.

PMID: 17932604

Bloodstream infections are an important cause of morbidity and mortality among hospitalized patients and the surveillance of etiological agents in these infections is important for their prevention and treatment. Data on common organisms isolated from blood cultures from Malaysia are limited, and our aim was to identify the common bloodstream isolates in hospitalized patients at the University of Malaya Medical Centre (UMMC), Kuala Lumpur, Malaysia.

Emergence of HIV-1 CRF01_AE/B unique recombinant forms in Kuala Lumpur, Malaysia

Tee KK, Pon CK, Kamarulzaman A, Ng KP

AIDS, 2005 Jan 28;19(2):119-26.

PMID: 15668536

OBJECTIVES: To investigate the molecular epidemiology of HIV-1 and to screen for the emergence of intersubtype recombinants in Kuala Lumpur, Malaysia.

DESIGN: A molecular epidemiology study was conducted among HIV-1 seropositive patients attending the University Malaya Medical Center (UMMC) from July 2003 to June 2004.

METHODS: Protease (PR) and reverse transcriptase (RT) gene sequences were derived from drug resistance genotyping assay of 100 newly diagnosed or antiretroviral-naive patients. These were phylogenetically analysed to determine the subtypes and recombination breakpoint analyses were performed on intersubtype recombinants to estimate the recombination breakpoint(s).

RESULTS: CRF01_AE predominated in Kuala Lumpur with 65% in both PR and RT genes. B subtype was detected at 14% and 12% in PR and RT genes, respectively. C subtype was present at 1% in both genes. Overall, the concordance of PR and RT genes in discriminating subtypes/circulating recombinant forms (CRF) was high at 96%. In this study, novel CRF01_AE/B intersubtype recombinants were detected at high prevalence (22%), including those isolates with subtype discordance. Thai variants of CRF01_AE and B subtype were involved in the genesis of these unique recombinant forms (URF). Interestingly, 19 CRF01_AE/B intersubtype recombinant isolates shared similar recombination breakpoints in both PR and RT genes. Several distinct URF were also identified.

CONCLUSION: PR and RT genes can be utilized for subtype/CRF assessment with high degree of agreement, allowing concurrent surveillance of circulating HIV-1 subtypes with antiretroviral drug resistance genotyping tests. The emergence of highly identical CRF01_AE/B intersubtype recombinants suggests the possibility of the appearance of a new circulating recombinant form in Kuala Lumpur.

Molecular subtyping of clinical isolates of Candida albicans and identification of Candida dubliniensis Malaysia

Tay ST, Chai HC, Na SL, Ng KP

Mycopathologia, 2005 Apr;159(3):325-9.

PMID: 15883714

The genotypes of 221 recent isolates of Candida albicans from various clinical specimens of 213 patients admitted to the University Malaya Medical Centre, Malaysia was determined based on the amplification of a transposable intron region in the 25 S rRNA gene. The analyses of 178 C. albicans isolated from nonsterile clinical specimens showed that they could be classified into three genotypes: genotype A (138 isolates), genotype B (38 isolates) and genotype C (2 isolates). The genotyping of 43 clinical isolates from sterile specimens showed that they belonged to genotype A (29 isolates), genotype B (10 isolates), genotype C (2 isolates) and genotype D (2 isolates). The overall distribution of C. albicans genotypes in sterile and nonsterile specimens appeared similar, with genotype A being the most predominant type. This study reported the identification of C. dubliniensis (genotype D) in 2 HIV-negative patients with systemic candidiasis, which were missed by the routine mycological procedure. The study demonstrated the genetic diversity of clinical isolates of C. albicans in Malaysia.

Fulltext Detection of medically important Candida species by absolute quantitation real-time polymerase chain reaction

Than LT, Chong PP, Ng KP, Seow HF

Jundishapur J Microbiol, 2015 Jan;8(1):e14940.

PMID: 25789129 DOI: 10.5812/jjm.14940

The number of invasive candidiasis cases has risen especially with an increase in the number of immunosuppressed and immunocom promised patients. The early detection of Candida species which is specific and sensitive is important in determining the correct administration of antifungal drugs to patients.

Fulltext First report of cervicofacial lymphadenitis due to Mycobacterium haemophilum in an immunocompromised adult patient

Atiya N, Sulaiman H, Chong J, Ng KP

J Infect Dev Ctries, 2015 Mar;9(3):313-6.

PMID: 25771471 DOI: 10.3855/jidc.5208

We report the first case of an immunocompromised adult patient presenting with cervicofacial lymphadenitis due to Mycobacterium haemophilum, confirmed using hsp65 gene sequencing and line-probe assays. In resource-limited settings, especially in developing countries, appropriate culture methods and rapid molecular diagnostic tools such as hsp65 gene sequencing for identification of this organism may not be readily available. This may cause M. haemophilum infections to go unrecognised or lead to delays in diagnosis. Lack of heightened awareness about the potential for this mycobacterial species to cause infections may also contribute to possible underestimation of M. haemophilum cases in the developing world.

Dermatophytes isolated from patients in University Hospital, Kuala Lumpur, Malaysia

Ng KP, Soo-Hoo TS, Na SL, Ang LS

Mycopathologia, 2002;155(4):203-6.

PMID: 12650596

A total of 576 dermatophytes were isolated from patients with a variety of skin infections from January 1993 to May 2000. Ten species of dermatophytes were identified: Epidermophyton floccosum (0.7%), Microsporum audouinii (1.1%), M. canis (3.1%), M. gypseum (0.3%), Trichophyton concentricum (3.5%), T. equinum (0.2%), T. mentagrophytes (36.1%), T. rubrum (53.8%), T. verrucosum (0.2) and T. violaceum (1.0%). The body sites most frequently affected by dermatophytes were the buttocks, nails and trunk. Anthropophilic dermatophytes made up 60.1% of the isolates; the most common species was T. rubrum, T. mentagrophytes and M. canis were the two main zoophilic dermatophytes. T. mentagrophytes was isolated from all body sites except the scalp. M. canis was found to be associated with domestic dogs and was not isolated from ethnic Malays. The only geophilic dermatophyte was M. gypseum, an uncommon dermatophyte associated with tinea pedis.

Systemic Candida infection in University hospital 1997-1999: the distribution of Candida biotypes and antifungal susceptibility patterns

Ng KP, Saw TL, Na SL, Soo-Hoo TS

Mycopathologia, 2001;149(3):141-6.

PMID: 11307597

A total of 102 Candida species were isolated from blood cultures from January 1997 to October 1999. Using assimilation of carbohydrate test, 52 (51.0%) of the Candida sp. were identified as C. parapsilosis, 25.5% (26) were C. tropicalis. C. albicans made up 11.8% (12), 6.9% (7) were C. rugosa, 3.8% (4) C. glabrata and 1% (1) C. guilliermondii. No C. dubliniensis was found in the study. In vitro antifungal susceptibility tests showed that all Candida species were sensitive to nystatin, amphotericin B and ketoconazole. Although all isolates remained sensitive to fluconazole, intermediate susceptibility was found in 3 C. rugosa isolates. Antifungal agents with high frequency of resistance were econazole, clotrimazole, miconazole and 5-fluorocytosine. Candida species found to have resistance to these antifungal agents were non-C. albicans.

Fulltext A seroprevalence study of viral hepatitis E infection in human immunodeficiency virus type 1 infected subjects in Malaysia

Ng KP, He J, Saw TL, Lyles CM

Med J Malaysia, 2000 Mar;55(1):58-64.

PMID: 11072492 MyJurnal

Hepatitis E virus (HEV) is a RNA virus transmitted enterically. A study of anti-HEV antibodies in 145 human immunodeficiency virus type 1 (HIV-1) infected subjects found that 14.4% of them were reactive to anti-HEV antibodies. Anti-HEV IgG and anti-HEV IgM was detected in 10.3% and 4.1% of the subjects respectively. Prevalence of anti-HEV (either IgG or IgM) was similar across all adult ages (p = 0.154), between the three ethnic groups (p = 0.378), and across risk groups (p = 0.120). The results showed that HEV infection in subjects recruited in this study was most likely transmitted via faecal-route.

Evaluation of a rapid test for the detection of antibodies to human immunodeficiency virus type 1 and 2

Ng KP, Saw TL, Baki A, He J, Singh N, Lyles CM

Int J STD AIDS, 1999 Jun;10(6):401-4.

PMID: 10414883

Hema-Strip HIV-1/2 is a one-step rapid test for the detection of anti-HIV-1/2 antibodies in whole blood. The test requires no expensive equipment and the results are available within 10-15 min. Using 72 known HIV-1 positive samples and 780 high-risk prisoners, the sensitivity and specificity of Hema-Strip HIV-1/2 was found to be comparable to microparticle enzyme immunoassay (MEIA). The data also indicated that Hema-Strip HIV-1/2 is an effective alternate testing system to conventional ELISA where the use of ELISA is not suitable and the result of the HIV testing is needed urgently.

Fulltext Disseminated Geotrichum infection

Ng KP, Soo-Hoo TS, Koh MT, Kwan PW

Med J Malaysia, 1994 Dec;49(4):424-6.

PMID: 7674982

Intensive chemotherapy has prolonged survival in cancer patients. Unfortunately it has also predisposed them to unusual infections because of their immunocompromised state. We report a case of fungal septicaemia caused by Geotrichum candidum, an imperfect yeast of low virulence in a young girl with acute lymphoblastic leukaemia. It was successfully treated with amphotericin B. The morphological characteristics of this fungus leading to its identification are described.

Impact of the Expanded Program of Immunization against hepatitis B infection in school children in Malaysia

Ng KP, Saw TL, Baki A, Rozainah K, Pang KW, Ramanathan M

Med Microbiol Immunol, 2005 May;194(3):163-8.

PMID: 15834754

The implementation of the Expanded Program of Immunization (EPI) in 1989 has dramatic impact on hepatitis B virus (HBV) infection in school children in Malaysia. A cross-sectional seroprevalence study of HBV infection in 190,077 school children aged 7-12 years from 1997 to 2003 showed a steady decline of HBV surface antigen (HBsAg) prevalence rate from 2.5% for children born in 1985 to 0.4% among school children born in 1996. The overall prevalence of HBsAg was 0.6%, 0.7% in males and 0.6% in females. Over 92.7% of school children had been vaccinated with HBV vaccine, in which 93.7% were vaccinated under the EPI and 6.3% on voluntary basis. The school children vaccinated under EPI had a 0.4% HBsAg carrier rate, which was significantly lower than school children vaccinated on a voluntary basis (HBsAg carrier rate 1.3%) and non-vaccinated school children (HBsAg carrier rate 2.7%), suggesting that HBV vaccination of infants was the most effective measure in preventing vertical transmission of HBV in the hyperendemic region.

Proteinase, phospholipase, biofilm forming abilities and antifungal susceptibilities of Malaysian Candida isolates from blood cultures

Tay ST, Abidin IA, Hassan H, Ng KP

Med Mycol, 2011 Jul;49(5):556-60.

PMID: 21254967 DOI: 10.3109/13693786.2010.551424

This study was conducted to determine the proteinase, phospholipase, and biofilm forming abilities of Candida isolates in blood cultures of specimens from patients at the University Malaya Medical Center, Kuala Lumpur, Malaysia. Proteinase and phospholipase activities were detected in 93.7% and 73.3%, respectively, of 15 Candida albicans isolates. Amongst the 26 non-C. albicans Candida isolates, proteinase and phospholipase activities were detected in 88.5% and 7.7% of the isolates, respectively. There was no significant difference in the expression levels of proteinase amongst the Candida isolates studied (P = 0.272), but the phospholipase activity of C. albicans was significantly higher than that of the non-C. albicans Candida isolates (P = 0.003). There was no significant difference in the biofilm forming abilities of C. albicans and non-C. albicans Candida isolates on the polystyrene microtiter wells (P = 0.379). In addition, the findings of this study demonstrate increased resistance of Candida isolates in biofilms to amphotericin and fluconazole, as compared to their planktonic counterparts.

Chong PP, Lee YL, Tan BC, Ng KP

J Med Microbiol, 2003 Aug;52(Pt 8):657-66.

PMID: 12867559

The aims of this study were to compare the genetic relatedness of: (i) sequential and single isolates of Candida strains from women with recurrent vaginal candidiasis (RVC); and (ii) Candida strains from women who had only one episode of infection within a 1-year period. In total, 87 isolates from 71 patients were cultured, speciated and genotyped by random amplification of polymorphic DNA (RAPD) analysis. Patients were categorized into three groups, namely those with: (i) a history of RVC from whom two or more yeast isolates were obtained (group A); (ii) a history of RVC from whom only a single isolate was obtained (group B); and (iii) a single episode of vaginal candidiasis within a 1-year period (group C). Six yeast species were detected: Candida albicans, Candida glabrata, Candida lusitaniae, Candida famata, Candida krusei and Candida parapsilosis. Interestingly, the prevalence of non-albicans species was higher in group A patients (50 %) than in patients in groups B (36 %) or C (18.9 %). Eighty RAPD profiles were observed, with a total of 61 polymorphic PCR fragments of distinct sizes. Clustering analysis showed that, overall, the majority of patients in group A had recurrent infections caused by highly similar, but not identical, sequential strains [mean pairwise similarity coefficient (S(AB)) = 0.721 +/- 0.308]. The range of mean S(AB) values for intergroup comparisons for C. albicans isolates alone was 0.50-0.56, suggesting that there was no significant relatedness between strains from different groups. Genetic similarity of C. albicans isolates from patients in group A was lower than that of C. albicans isolates from patients in group C (mean S(AB) = 0.532 +/- 0.249 and 0.636 +/- 0.206, respectively); this difference was statistically significant (P = 0.036). These results demonstrate that the cause of recurrent infections varies among individuals and ranges between strain maintenance, strain microevolution and strain replacement; the major scenario is strain maintenance with microevolution. They also show that C. albicans strains that cause recurrent infections are less similar to each other than strains that cause one-off infections, suggesting that the former may represent more virulent subtypes.

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