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

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 35°C 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

Identification of local clinical Candida isolates using CHROMagar Candida TM as a primary identification method for various Candida species.

The objective of our study was to study the effectiveness of CHROMagar Candida TM as the primary identification method for various clinical Candida isolates, other than the three suggested species by the manufacturer. We studied 34 clinical isolates which were isolated from patients in a local teaching hospital and 7 ATCC strains. These strains were first cultured in Sabouraud dextrose broth (SDB) for 36 hours at 35°C, then on CHROMagar plates at 30°C, 35°C and 37°C. The sensitivity of this agar to identify Candida albicans, Candida dubliniensis, Candida tropicalis, Candida glabrata, Candida rugosa, Candida krusei and Candida parapsilosis ranged between 25 and 100% at 30°C, 14% and 100% at 35°C, 56% and 100% at 37°C. The specificity of this agar was 100% at 30°C, between 97% and 100% at 35°C, 92% and 100% at 37°C. The efficiency of this agar ranged between 88 and 100% at 30°C, 83% and 100% at 35°C, 88% and 100% at 37°C. Each species also gave rise to a variety of colony colours ranging from pink to green to blue of different colony characteristics. Therefore, the chromogenic agar was found to be useful in our study for identifying clinical Candida isolates

Hyaluronatelyase production by Streptococcus pneumoniae isolated from patients and carriers

Hyaluronatelyase produced by various microorganisms are capable of degrading hyaluronic acid in connective tissues and initiating the spread of infection by opening an access for the pathogen into host tissues. The present study attempts to determine the distribution of hyaluronatelyase-producing Streptococcus pneumoniae among invasive, non invasive and carriage isolates, and correlate it with the clinical sources, year of isolation, colonial morphology and their serotypes. A total of 100 isolates from various clinical samples were selected and screened for hyaluronatelyase production and presence of the encoding SpnHyl gene. All isolates possessed SpnHyl gene. Ninety-six isolates including 34 carriage isolates were positive for production of hyaluronatelyase. Four hyaluronatelyase-negative isolates were from blood (2 isolates) and sputum (2 isolates). No significant association was detected among hyaluronatelyase production and bacterial characteristics except for colonial morphology (p = 0.040). High percentages of hyaluronatelyase production in these isolates suggest their possible role as human pathogens

Hymenolepis nana in a renal transplant recipient : to treat or not to treat?

A case of hymenolepiasis in a renal transplant recipient. Issues discussed include the benefit of anti-parasitic agents as well as the preventive measures

Diphtheria anti-toxoid antibody levels among pre-clinical students and staff in an institute of higher learning in Malaysia: are they protected?

Introduction: Little is known about the sero-prevalence of diphtheria anti-toxoid antibody levels among medical students in Malaysia. They too, just like other health care workers (HCWs) are at risk of contracting and transmitting diphtheria. Fortunately, this can be prevented by giving a specific vaccine: the diphtheria, tetanus and pertussis (DTP) vaccine. Nonetheless, data from local or regional surveys are needed before any decision is made by the respective authorities. General objective: We studied the epidemiology of diphtheria anti-toxoid antibody levels and vaccination history amongst medical students and staff in Faculty of Medicine and Health Sciences, Universiti Putra Malaysia. Specific objectives: We determined the level of diphtheria anti-toxoid antibodies amongst pre-clinical students and staff. Methodology: A total of 152 sera were collected from subjects aged 19 to 63, and diphtheria anti-toxoid levels were measured by an enzyme-linked immunosorbent assay. Results: One hundred and fifty-two (94.4%) blood samples out of 161 participants were successfully withdrawn, which comprised 105 (69.1%) and 47 (30.9%) medical students and staff, respectively. A total of 77.6% and the other 22.4% of the subjects had full and basic protection, respectively. Higher levels were predominant amongst males and they were 1.3 times more protected than females in 20-29 year-old group (85.1% vs 66.2%; odd ratios 1.25 [95% CI 1.03-1.50]; P=0.03). No significant difference in the levels of immunity among subjects for ethnicity and academic position (P>0.05). Recommendations: Level of full protection against diphtheria toxin should be clearly defined by broad population based studies using several comparable detection methods. Medical students and staff with basic protection should be closely monitored or should be given a booster dose for those who are at high risk of acquiring the disease. Thus, a standard degree of coverage should be clearly determined for health workers to prevent a potential outbreak. Conclusion: Students and staff possess immunity towards diptheria toxin however the level of full protective antibody is yet to be determined in future

Prevalence of macrolide resistance and in vitro activities of six antimicrobial agents against clinical isolates of streptococcus pneumoniae from a multi-center surveillance in Malaysia

The in vitro activities of 6 antimicrobial agents against clinical isolates of Streptococcus pneumoniae (pneumococci) were investigated and the erythromycin minimum inhibitory concentrations (MICs) were correlated with the two major macrolide resistance determinants, mef(A) and erm(B). MICs of commonly used antibiotics as well as the presence of macrolide resistance determinant genes in all isolates were tested. Seventy one pneumococcal isolates collected at Institute for Medical Research (IMR) were included in this study. Phenotypic characterization, MIC determination using E-test strips and polymerase chain reactions for antibiotic resistance determination were included. Among the isolates, 25 (35.2%) isolates were erythromycin susceptible, 3 (4.2%) were intermediate and 42 (60.6%) were resistant. Fifty three isolates (74.7%) were found with mef(A) alone, 15 (21.1%) isolates with erm(B) + mef(A) combination and 3 (4.2%) isolates with none of the two genes. The in vitro activity of penicillin, amoxicillin clavulanic acid, ceftriaxone and cefotaxime is superior to trimethoprim-sulfamethoxazole and erythromycin. In conclusion, pneumococcal isolates in this study were highly susceptible to penicillin with very low MICs. However, a very high prevalence rate of erythromycin resistance was observed. Erythromycin resistant S. pneumoniae isolates with both mef(A) and erm(B) showed very high MICs ≥256 μg/mL

Evaluation of PCR-based approach for serotype determination of Streptococcus pneumoniae

Determination of Streptococcus pneumoniae serotypes is essential for epidemiological surveillance. Therefore accurate, reliable and cost effective serotyping method is crucial. In this study, we determined the serotypes of 41 pneumococcal isolates recovered from human anterior nares by multiplex Polymerase Chain Reaction (PCR) utilizing published primers. The data was then compared with conventional serology using latex agglutination (LA) and the Quellung reaction. Based on the PCR-approach, 8 different serogroups/serotypes were detected with one isolate classified as non-typeable (cpsA- negative). In reference to the serology-based data, the results were in agreement except for one isolate. For the latter isolate, the LA and Quellung tests failed to show a reaction but the PCR-approach and sequencing identified the isolate as serogroup 15B/C. Based on this experimental setting, we found that the PCR-approach for pneumococcal serotypes determination is reliable to serve as the alternative for determining the pneumococcal serotyping

In vitro antifungal activity of allicin alone and in combination with two medications against six dermatophytic fungi

Dermatophytes are fungi capable of invading keratinized tissues of humans and animals, causingdermatomycosis. Azole antifungal drugs are often used in the treatment of dermatomycosis. Because ofincreased use of these medications, azoles are known to cause drug resistance; hence this studyinvestigated an alternative anti-dermatophyte which is plant-based, and biodegradable natural product.Allicin is a pure bioactive compound derived from garlic, which is known worldwide for its antifungalactivities. This study evaluated thein vitro efficacy of pure allicin alone against six dermatophyteisolates and the MIC50 and MIC90 ranged from 0.098 – 25.0 µg/ml. Results of this study showed that theorder of efficacy based on the MICs values was fluconazole > allicin > ketoconazole at 28ºC for both 7and 10 days incubation. On the other side, most of tested drug combinations demonstrated synergisticor additive interaction for all isolates for both 7 and 10 days incubation at 28ºC. In conclusion allicinalone showed very good potential as an antifungal compound against mycoses-causingdermatophytes, performing better than the synthetic drug fluconazole, and almost the same asketoconazole, furthermore allicin in combination with ketoconazole or with fluconazole frequentlyshowed synergistic or additive interaction against dermatomycosis

Community acquired pneumonia in Malaysia: is Streptococcus pneumoniae an important pathogen?

Previous data on etiological agents isolated from adult patients with community acquired pneumonia (CAP) in Malaysia has showed very low percentage of Streptococcus pneumoniae. Thus, we used immunochromatography test (ICT) and real-time polymerase chain reaction (PCR) in addition to conventional culture methods for S. pneumoniae detection. We found that the detection rate was highest by real time PCR reaction (50%) in contrast to 10% by ICT, 2% from blood and 0% from sputum cultures. This molecular method had contributed to a rise in percentage of S. pneumoniae detection accounting for 51.1% of all etiological cases in CAP and the second commonest organism after Chlamydophila pneumoniae (63.8%), followed by M. pneumoniae (27.7%) and L. pneumophila (17%). We have also found that 10.6% of the etiological agents of CAP were not known indicating that other specific organisms including viruses have not been identified. Both ICT and PCR demonstrated sensitivities of 100%, with specificities of 91.3 and 55.6%, respectively, using culture techniques as the “gold standard”. Thus from this finding, they will become potential tools in the future for the diagnosis of S. pneumoniae in CAP, for the epidemiological importance and prevention as well as for early antibiotic management

Identification and differentiation of Candida species using specific polymerase chain reaction (PCR) amplification of the phospholipase B gene

Candida species are the major cause of mortality in both immunocompromised and critically ill patients. Therefore, the early diagnosis and differentiation of Candida species isolated from clinical samples is principally important due to their inherently variable antifungal resistance pattern. Herein, rapid and species-specific polymerase chain reaction (PCR)-based molecular method was developed for the identification of the four species of Candida most commonly isolated from clinical specimens, namely Candida albicans, Candida parapsilosis, Candida glabrata and Candida tropicalis. The developed method targeted the phospholipase B gene (PLB) as a novel target. We determined the sequences of this gene in previous work. The primers designed achieved highly specific identification of the selected species using simplex PCR assay, which were confirmed by sequencing. There was no cross-amplification of other Candida species nor other fungal organisms tested. The simplex PCR assay yielded detection limits of 1 to 10 cells/ml and 10 fg/µl DNA. These results showed that the PLB gene provides a novel target that could be used for the identification and detection of medically important Candida species from the clinical samples