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Thangam Menon

Publications and source records attributed to Thangam Menon.

17 recordsLinked to original sources
PubMed2006

Phospholipase and proteinase activities of clinical isolates of Candida from immunocompromised patients.

Sixty-one isolates of Candida recovered from HIV seropositive and cancer patients were studied for elaboration of putative virulence determinants--phospholipase (PL) and secreted aspartyl proteinase (Sap). Forty two (68.85%) isolates examined were PL producers and 51 (83.6%) were positive for Sap. 57.37% (35/61) isolates produced both enzymes. Enzymatic activity was more pronounced in Candida albicans with 100% PL and 94.1% Sap activity. In contrast, non-C. albicans species demonstrated only 29.6% PL and 70.3% Sap activity, indicating interplay of other virulence determinants in these yeasts in colonization and disease.

Aspartic Acid Endopeptidases↗
PubMed2006

Molecular analysis and susceptibility profiling of Candida albicans isolates from immunocompromised patients in South India.

The genetic diversity and in vitro antifungal susceptibility profiles of 55 Candida albicans from immunocompromised patients were studied. PCR based analysis of the transposable intron in the 25S rDNA revealed 39 genotype A, 4 genotype B and 12 genotype C isolates. Serotype analysis categorized 52 isolates as serotype A and 3 as serotype B. All strains were susceptible to micafungin, 5-flucytosine and miconazole, whereas resistance against amphotericin B (3.6%), fluconazole (3.6%), itraconazole (7.3%) and voriconazole (5.5%) was observed. No association was seen between antifungal resistance and genotype/serotype status.

Antifungal Agents↗
PubMed2006

Biofilm production by clinical isolates of Candida species.

Candida species are a leading cause of infections especially in immunocompromised hosts. Usage of bio-prostheses such as IV lines and urinary catheters provide ample opportunity for Candida biofilms to set up a nidus for disease that is not easily amenable to conventional antifungal therapy. To understand the prevalence of biofilm producers among clinical isolates, 58 Candida isolates from immunocompromised patients were examined. Thirty of the 36 (83.3%) blood stream' isolates and 18 of the 22 (81.8%) oral isolates were biofilm producers. Biofilm producing blood stream isolates were significantly more among non-C. albicans Candida (93.1%) in comparison to C. albicans (42.9%).

Biofilms↗
PubMed2006

Esterase activity of Candida species isolated from immunocompromised hosts.

A total of 149 clinical isolates of Candida species isolated from immunocompromised patients were examined to ascertain their esterase activity by the Tween 80 opacity test, which is a biochemical test used mainly to differentiate between Candida albicans and Candida dubliniensis. Our results showed that C. albicans (92.3%), Candida tropicalis (92.3%), Candida parapsilosis (25%), C. dubliniensis (16.6%), Candida inconspicua (100%), and Candida lipolytica (100%) produced opacity halos through the 10-day post-inoculation period. The remaining Candida species did not produce a positive test response. These findings indicate that Tween 80 opacity test cannot be used as the sole phenotypic trait in the differentiation of C. albicans and C. dubliniensis.

Candida↗
PubMed2006

Pharyngeal carriage of group A streptococci in school children in Chennai.

BACKGROUND & OBJECTIVES: Asymptomatic pharyngeal carriage of group A streptococci (GAS) in children may lead to spread of respiratory infections in the community. Data on healthy GAS carriers in the community are therefore important. We carried out this preliminary study to screen the school children from various parts of Chennai city, south India to detect pharyngeal carriage of GAS. METHODS: Throat swabs were collected from 1,173 school children aged 5 to 17 yr from different locations in Chennai. The isolates of beta haemolytic streptococci were serogrouped by agglutination tests using specific antisera. RESULTS: Beta haemolytic streptococci were isolated from 16.3 per cent of 1,102 asymptomatic children. 71 children of the study group had untreated tonsillitis positive for beta haemolytic streptococci. The percentage of asymptomatic GAS carriers was 8.4 per cent. INTERPRETATION & CONCLUSION: The high carriage rate of beta haemolytic streptococci seen in children poses a threat to the community and should be checked. Regular screening needs to be done in various parts of the country.

Adolescent↗
PubMed2006

Infective endocarditis due to Acinetobacter baumannii complex--a case report.

We report a case of infective endocarditis caused by Acinetobacter baumannii complex in a 27-year-old male patient. The patient presented with fever of five days duration, palpitation, dyspnea, cough and chest pain. He had undergone a surgical repair of ruptured aneurysm of sinus of valsalva a month before. The transthoracic echocardiogram revealed a large vegetation on the aortic valve. Three samples of blood for culture grew gram-negative pleomorphic coccobacilli within 24 hours which were identified by cultural and biochemical characteristics to be Acinetobacter baumannii complex. Antimicrobial susceptibility was performed by Kirby-Bauer method and the isolate were found to be resistant to ampicillin, Ciprofloxacin, Ceftriaxone, Gentamicin, Amikacin, Augmentin, Levofloxacin, Piperacillin-Tazobactam, Netilimicin and sensitive to Imipenem. Patient was initially treated with Ceftraixone and Gentamicin and subsequently with Ampicillin and Amikacin but did not respond to treatment and died of sepsis before therapy with Imipenem could be started.

Acinetobacter Infections↗
PubMed2005

Tobacco agar: a new medium for chlamydosporulation in Candida albicans and Candida dubliniensis.

Chlamydospores are a distinctive morphologic feature of Candida albicans and Candida dubliniensis and aid in their identification. A new medium, tobacco agar, for chlamydosporulation in Candida is described. All the strains of C. dubliniensis and 96% of isolates of C. albicans tested produced chlamydospores after 24 h incubation on tobacco agar, whereas none of the other seven species produced chlamydospores.

Agar↗
PubMed2005

Candidosis in children with onco-hematological diseases in Chennai, south India.

Candida spp. are recognized as a leading contributor to mortality and morbidity in patients with onco-hematological malignancies. The rates and risk factors for mycotic infections in pediatric oncology patients are undetermined, particularly for those treated at centers in developing countries. The objective of the present study was to prospectively evaluate the species stratification and antifungal susceptibility profile of Candida spp. associated with superficial and systemic infection in children with onco-hematological diseases. Acute lymphoblastic leukemia was the most common underlying disease (71.4%) among the 91 children under study. Candida albicans was the predominant species, with 17/29 isolates (58.6%); followed by C. tropicalis, with 10/29 isolates (34.5%). The drug susceptibility data analysis for the clinical isolates of Candida revealed 17.2% (5/29) resistance to fluconazole. This study reinforces the need for the systematic surveillance of candidosis for the correct management of such life-threatening infections.

Antifungal Agents↗
PubMed2005

Isolation, distribution and prevalence of various species of enterococci isolated from clinical specimens in a tertiary care hospital.

Various clinical specimens were processed to find the prevalence rate of enterococci and to identify the species of clinical isolates of enterococci. Screening of various clinical specimens revealed that enterococci were prevalent in 2% of the total specimens, with urine and wound to be the major site of isolation. Conventional test scheme proposed by Facklam and Collins and commercially available systems Rapid ID 32 Strep (biomereiux) were successfully used to speciate enterococcal strains. Five species of enterococci were identified in the study from a set of 396 cultures, with E. faecalis (79.79%), and E. faecium (11.11%) predominating. E. hirae (3.03%), E. gallinarum (3.03%), and E. casseliflavus (3.03%), were the other members of Enterococcus species identified.

Cross Infection↗
PubMed2004

Biotypes of group A streptococci isolated from children.

Thirty-eight isolates of group A streptococci from patients with pharyngitis, 13 isolates from patients with pyoderma and 28 carrier strains were subjected to biotyping by carbohydrate fermentation tests and production of beta-glucuronidase. Biotype 10 was observed most frequently among clinical isolates and biotypes 3 and 4 were most common among carrier isolates.

Adolescent↗
PubMed2004

Group A streptococcal infections of the pharynx in a rural population in south India.

BACKGROUND & OBJECTIVES: There has been a resurgence in the incidence of rheumatic heart disease all over the world and hence surveillance and strain characterization are important. The aim of this study was to screen children in a rural community in south India for throat carriage of group A streptococci and to clinically assess them for signs of rheumatic heart disease. METHODS: Throat swabs were collected from children (5-14 yr) in the village of Orathur, Tamil Nadu and cultured on tryptose blood agar plates. Beta haemolytic streptococci were serogrouped using Streptex kit and biotyped based on their ability to ferment carbohydrates and production of beta-glucuronidase enzyme. Blood samples were also collected and antibodies to streptolysin O demonstrated by latex agglutination tests. All the children were examined by a paediatrician; ECG and echocardiography were performed to assess cardiac function. RESULTS: Eighty of the 310 children included in the study had symptoms of acute respiratory infections; 16 of them grew beta haemolytic streptococci of which 8 belonged to group A (10%). Biotype 4 was most common. Antistreptolysin O (ASO) test did not correlate with culture results. Two of 310 children had rheumatic heart disease but both were culture negative. INTERPRETATION & CONCLUSION: Pharyngeal carriage of group A streptococci was common in this population. The prevalence of rheumatic heart disease was 0.6 per cent. The study emphasizes the need for active surveillance and characterization of GAS isolates.

Adolescent↗
PubMed2004

Rapid discrimination between strains of beta haemolytic streptococci by intact cell mass spectrometry.

BACKGROUND & OBJECTIVES: Beta haemolytic streptococci belonging to Lancefield group A, B, C and G cause a wide spectrum of clinical diseases. Hence there is a need for rapid and accurate typing of these strains. The present study was undertaken to evaluate the use of intact cell matrix assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) for rapid discrimination between strains of beta haemolytic streptococci. METHODS: Colonies of beta haemolytic streptococci were emulsified with chemical matrix on the sample slide, dried and analyzed by MALDI-TOF-MS. RESULTS: The reproducibility of results for all groups of beta haemolytic streptococci was good and spectra obtained for Lancefield group A, C and G streptococci showed discrimination between the groups on visual comparison. A finer difference in spectrum was observed among group A streptococci isolated from different locations at different periods of time. INTERPRETATION & CONCLUSION: MALDI-TOF-MS may be a potential tool in discriminating between strains of beta haemolytic streptococci, and also in the characterisation of untypable strains of group A streptococci.

Adolescent↗
PubMed2003

Prevalence of antibodies to hepatitis A and hepatitis E virus in urban school children in Chennai.

With similar feco-oral mode of transmission of Hepatitis A and E viruses, and improving levels of personal hygiene among higher socioeconomic population, periodic surveillance on HAV/HEV exposure pattern may be of immense public health value. One such attempt was made in Tamilnadu, India by analysing the presence of antibodies to HAV and HEV in 185 healthy children of 6 months to 12 years of age. While anti HAV positivity was 96.9% by 12 years of age, anti HEV positivity fluctuated between 5.3-16.7%. The study suggests the necessity for developing a vaccine for HEV to prevent the frequent occurrence of HEV outbreaks in India, since natural HEV exposure does not bestow significant protection as observed in HAV.

Age Distribution↗
PubMed2003

Occurrence of group C Streptococci in children in a South Indian village.

Throat swabs were collected from 310 children aged 5-14 years attending a rural health camp at Orathur near Chennai. Group C Streptococci were isolated from 13/310 (4.19%) cases. Seven out of 13 patients had symptoms of respiratory tract infection. Biochemical characterization of the isolates was done by hemolytic characteristics, Voges-Proskauer test, fermentation of trehalose and sorbitol and hydrolysis of 4-methylumbelliferyl-D-â-glucuronide. Four out of 13 strains were identified as S. equisimilis.

Adolescent↗