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REVIEW ARTICLES
Review of clinical and laboratory features of human Brucellosis
BG Mantur, SK Amarnath, RS Shinde
July-September 2007, 25(3):188-202
DOI:10.4103/0255-0857.34758  PMID:17901634
Infection with Brucella spp. continues to pose a human health risk globally despite strides in eradicating the disease from domestic animals. Brucellosis has been an emerging disease since the discovery of Brucella melitensis by Sir David Bruce in 1887. Although many countries have eradicated B. abortus from cattle, in some areas B. melitensis and B. suis have emerged as causes of this infection in cattle, leading to human infections. Currently B. melitensis remains the principal cause of human brucellosis worldwide including India. The recent isolation of distinct strains of Brucella from marine mammals as well as humans is an indicator of an emerging zoonotic disease. Brucellosis in endemic and non-endemic regions remains a diagnostic puzzle due to misleading non-specific manifestations and increasing unusual presentations. Fewer than 10% of human cases of brucellosis may be clinically recognized and treated or reported. Routine serological surveillance is not practiced even in Brucella - endemic countries and we suggest that this should be a part of laboratory testing coupled with a high index of clinical suspicion to improve the level of case detection. The screening of family members of index cases of acute brucellosis in an endemic area should be undertaken to pick up additional unrecognised cases. Rapid and reliable, sensitive and specific, easy to perform and automated detection systems for Brucella spp. are urgently needed to allow early diagnosis and adequate antibiotic therapy in time to decrease morbidity / mortality. The history of travel to endemic countries along with exposure to animals and exotic foods are usually critical to making the clinical diagnosis. Laboratory testing is indispensable for diagnosis. Therefore alertness of clinician and close collaboration with microbiologist are essential even in endemic areas to correctly diagnose and treat this protean human infection. Existing treatment options, largely based on experience gained > 30 years ago, are adequate but not optimal. In our experience, an initial combination therapy with a three drug-regimen followed by a two-drug regimen for at least six weeks and a combination of two drugs with a minimum of six weeks seems warranted to improve outcome in children and adult patients respectively with laboratory monitoring. A safe and effective vaccine in humans is not yet available. Prevention is dependent upon the control of the disease in animal hosts, effective heat treatment of dairy produce and hygienic precautions to prevent occupational exposure. This review compiles the experiences and diagnostic and treatment paradigms currently employed in fighting this disease.
  142 48,761 3,922
GUEST EDITORIAL
Re-emergence of Chikungunya virus in India
V Ravi
April-June 2006, 24(2):83-84
DOI:10.4103/0255-0857.25175  PMID:16687855
  135 37,629 1,999
REVIEW ARTICLES
Probiotics
V Gupta, R Garg
July-September 2009, 27(3):202-209
DOI:10.4103/0255-0857.53201  PMID:19584499
The term "probiotic" was first used in 1965, by Lilly and Stillwell, to describe substances secreted by one organism which stimulate the growth of another. The use of antibiotics, immunosuppressive therapy and irradiation, amongst other means of treatment, may cause alterations in the composition and have an effect on the GIT flora. Therefore, the introduction of beneficial bacterial species to GI tract may be a very attractive option to re-establish the microbial equilibrium and prevent disease. Prebiotic is a non-digestible food ingredient that confers benefits on the host by selectively stimulating one bacterium or a group of bacteria in the colon with probiotic properties. Both probiotics and prebiotics are together called as Synbiotics. Various bacterial genera most commonly used in probiotic preparations are Lactobacillus, Bifidobacterium, Escherichia, Enterococcus, Bacillus and Streptococcus . Some fungal strains belonging to Saccharomyces have also been used. Probiotics have been shown to be effective in varied clinical conditions- ranging from infantile diarrhoea, necrotizing enterocolitis, antibiotic-associated diarrhoea, relapsing Clostridium difficle colitis, Helicobacter pylori infections, inflammatory bowel disease to cancer, female uro-genital infection and surgical infections. Lactobacillus rhamnosus strain GG has proven beneficial affects on intestinal immunity. It increases the number of IgA and other immunoglobulins secreting cells in the intestinal mucosa. It also stimulates local release of interferons. It facilitates antigen transport to underlying lymphoid cells, which serves to increase antigen uptake in Peyer's patches. Probiotics are live microorganisms, so it is possible that they may result in infection in the host. The risk and morbidity of sepsis due to probiotic bacteria should be weighed against the potential for sepsis due to more pathological bacteria and the morbidity of diseases for which probiotic bacteria are being used as therapeutic agents. Also, future, well-designed placebo controlled studies with validated results are required for ascertaining the true health benefits of probiotics The important point in this regard is careful selection of the probiotic agent, its dose standardization and a thorough knowledge of its beneficial effects.
  84 49,028 4,455
ORIGINAL ARTICLE
Detection of biofilm formation among the clinical isolates of staphylococci: An evaluation of three different screening methods
T Mathur, S Singhal, S Khan, DJ Upadhyay, T Fatma, A Rattan
January-March 2006, 24(1):25-29
DOI:10.4103/0255-0857.19890  PMID:16505551
Purpose: The purpose of this study was to evaluate three methods for detection of biofilm formation in staphylococci. Methods: For detection of biofilm formation, 152 clinical isolates of Staphylococcus spp. were screened by tissue culture plate (TCP), Tube method (TM) and Congo red agar (CRA) method. Results: Of the 152 Staphylococcus spp. 88(57.8%) displayed a biofilm-positive phenotype under the optimized conditions in the TCP method and strains were further classified as high 22 (14.47 %) and moderate 60 (39.4 %) while in 70 (46.0 %) isolates weak or no biofilm was detected. Though TM correlated well with the TCP test for 18 (11.8 %) strongly biofilm producing strains, weak producers were difficult to discriminate from biofilm negative isolates. Screening on CRA does not correlate well with either of the two methods for detecting biofilm formation in staphylococci. Conclusion: The TCP method was found to be most sensitive, accurate and reproducible screening method for detection of biofilm formation by staphylococci and has the advantage of being a quantitative model to study the adherence of staphylococci on biomedical devices.
  83 40,609 2,473
BRIEF COMMUNICATION
Evaluation of Methods for AmpC Beta-Lactamase in Gram Negative Clinical Isolates from Tertiary Care Hospitals
S Singhal, T Mathur, S Khan, DJ Upadhyay, S Chugh, R Gaind, A Rattan
April-June 2005, 23(2):120-124
DOI:10.4103/0255-0857.16053  PMID:15928443
The purpose of this study was to simultaneously screen for Extended-spectrum b-lactamases (ESBL) and AmpC b-lactamases in gram negative clinical isolates from four tertiary care hospitals and further to compare two detection methods three-dimensional extraction method and AmpC disk test for AmpC b-lactamases. A total of 272 isolates were screened for ESBL and AmpC β-lactamase by modified double disk approximation method (MDDM). Synergy observed between disks of ceftazidime/cefotaxime and clavulanate were considered as ESBL producer. Isolates showing reduced susceptibility to either of the test drugs (ceftazidime or cefotaxime) and cefoxitin were considered as presumptive AmpC producers and further confirmed by three-dimensional extraction method and AmpC disk test. A total of 173 (64%) of the isolates were found to be ESBL positive and 61 (23%) showed resistant to cefoxitin. ESBL was detected in 80 (62%) isolates of E. coli and 71 (73%) of Klebsiella spp. The occurrence of AmpC b-lactamases was found to be 8% (22) of the total isolates and the two detection methods for AmpC b -lactamase showed concordant results. Screening for ESBL and AmpC can be simultaneously done by MDDM method and confirmation for AmpC β-lactamase should be carried out routinely in tertiary care hospitals by AmpC disk test, as it is a simple and rapid procedure.
  77 21,800 1,755
REVIEW ARTICLE
Chikungunya fever: A re-emerging viral infection
M Chhabra, V Mittal, D Bhattacharya, UVS Rana, S Lal
January-March 2008, 26(1):5-12
DOI:10.4103/0255-0857.38850  PMID:18227590
Chikungunya (CHIK) fever is a re-emerging viral disease characterized by abrupt onset of fever with severe arthralgia followed by constitutional symptoms and rash lasting for 1-7 days. The disease is almost self-limiting and rarely fatal. Chikungunya virus (CHIKV) is a RNA virus belonging to family Togaviridae, genus Alphavirus. Molecular characterization has demonstrated two distinct lineages of strains which cause epidemics in Africa and Asia. These geographical genotypes exhibit differences in the transmission cycles. In contrast to Africa where sylvatic cycle is maintained between monkeys and wild mosquitoes, in Asia the cycle continues between humans and the Aedes aegypti mosquito. CHIKV is known to cause epidemics after a period of quiescence. The first recorded epidemic occurred in Tanzania in 1952-1953. In Asia, CHIK activity was documented since its isolation in Bangkok, Thailand in 1958. Virus transmission continued till 1964. After hiatus, the virus activity re-appeared in the mid-1970s and declined by 1976. In India, well-documented outbreaks occurred in 1963 and 1964 in Kolkata and southern India, respectively. Thereafter, a small outbreak of CHIK was reported from Sholapur district, Maharashtra in 1973. CHIKV emerged in the islands of South West Indian Ocean viz. French island of La Reunion, Mayotee, Mauritius and Seychelles which are reporting the outbreak since February, 2005. After quiescence of about three decades, CHIKV re-emerged in India in the states of Andhra Pradesh, Karnataka, Maharashtra, Madhya Pradesh and Tamil Nadu since December, 2005. Cases have also been reported from Rajasthan, Gujarat and Kerala. The outbreak is still continuing. National Institute of Communicable Diseases has conducted epidemiological, entomological and laboratory investigations for confirmation of the outbreak. These have been discussed in detail along with the major challenges that the country faced during the current outbreak.
  75 50,811 3,019
Onychomycosis - epidemiology, diagnosis and management
R Kaur, B Kashyap, P Bhalla
April-June 2008, 26(2):108-116
DOI:10.4103/0255-0857.40522  PMID:18445944
Onychomycosis is a fungal infection of nails caused by dermatophytes, yeasts or nondermatophyte molds and represents about 30% of mycotic cutaneous infections. Increasingly onychomychosis is being viewed as more than a mere cosmetic problem. In spite of improved personal hygiene and living environment, onychomycosis continues to spread and persist. The prevalence rate of onychomycosis is determined by age, predisposing factor, social class, occupation, climate, living environment and frequency of travel. Onychomycosis in immunocompromised patients can pose a more serious health problem. Dermatophytes are the most frequently implicated causative agents in onychomycosis. Previously regarded as contaminants, yeasts are now increasingly recognised as pathogens in fingernail infections, as are some moulds. Clinical diagnosis of onychomycosis is based on the patients' history; a physical examination, microscopy and culture of nail specimens. The treatment of onychomycosis has been attempted throughout the ages, but only in the last two decades have safe, effective systemic treatments been available for this chronic superficial fungal disease. Oral Griseofulvin and Ketoconazole; once the agents of choice for the treatment of onychomycosis, have been superseded by newer systemic compounds that have a higher cure and lower relapse rates, cause fewer side effects and are suitable for short-term dosing.
  68 35,947 2,437
BRIEF COMMUNICATION
Extended spectrum -lactamases in urinary isolates of escherichia coli and klebsiella pneumoniae - Prevalence and susceptibility pattern in a tertiary care hospital
S Babypadmini, B Appalaraju
July-September 2004, 22(3):172-174
PMID:17642726
A total of 411 urinary isolates (353 Escherichia coli and 58 Klebsiella pneumoniae) were studied for extended spectrum -lactamase (ESBL) production by double disk approximation test and NCCLS confirmatory test. ESBL production was found to be 41% in E.coli and 40% in K.pneumoniae. Fourteen percent and 12% of ESBL producers showed false susceptibility to ceftazidime and cefotaxime in routine susceptibility testing. The susceptibility of ESBL producers to imipenem, nitrofurantoin and amikacin was found to be 100%, 89% and 86% respectively. A high degree of associated resistance to gentamicin, co-trimoxazole and quinolones was found in ESBL producers. Majority of ESBL producers was detected among patients admitted in medical ICU and surgery ward.
  64 17,847 962
REVIEW ARTICLE
Alternatives to the tuberculin skin test: Interferon-γ assays in the diagnosis of Mycobacterium Tuberculosis infection
M Pai
July-September 2005, 23(3):151-158
DOI:10.4103/0255-0857.16585  PMID:16100419
For nearly a century, there were no alternatives to the tuberculin skin test (TST) for diagnosing latent tuberculosis infection. Because of advances in immunology and genomics, for the first time, an alternative has emerged in the form of T cell based interferon-g (IFN-g) assays, a new generation of in vitro tests of cellular immunity. These assays measure cell mediated immune response by quantifying IFN-g released by T cells in response to stimulation by Mycobacterium tuberculosis antigens. Although early versions of IFN-g assays used purified protein derivative (PPD) as the stimulating antigen, newer versions use antigens that are significantly more specific to M. tuberculosis. These specific antigens include ESAT-6 and CFP-10. These proteins, encoded by genes located within the region of difference 1 (RD1) segment of the M. tuberculosis genome, are more specific to M. tuberculosis than PPD because they are not shared with any BCG substrains or several nontuberculous mycobacterial species. A review of current evidence on the performance of IFN-g assays and TST suggests that both the TST and IFN-g assays have advantages and limitations, and both tests appear to be useful at this time. The emergence of IFN-g assays is a much anticipated, welcome development that has, for the first time, increased the choice of tests available for diagnosing latent tuberculosis infection. Because both tests have their strengths and limitations, the decision to select one over the other will depend on the population, the goal of testing, and the resources available. To fully evaluate the utility of IFN-g assays in high burden countries such as India, long-term cohort studies are needed to determine the association between positive IFN-g results and the subsequent risk of active disease.
  63 28,225 1,581
Bio-aerosols in indoor environment: Composition, health effects and analysis
Padma Srikanth, Suchithra Sudharsanam, Ralf Steinberg
October-December 2008, 26(4):302-312
DOI:10.4103/0255-0857.43555  PMID:18974481
Bio-aerosols are airborne particles that are living (bacteria, viruses and fungi) or originate from living organisms. Their presence in air is the result of dispersal from a site of colonization or growth. The health effects of bio-aerosols including infectious diseases, acute toxic effects, allergies and cancer coupled with the threat of bioterrorism and SARS have led to increased awareness on the importance of bio-aerosols. The evaluation of bio-aerosols includes use of variety of methods for sampling depending on the concentration of microorganisms expected. There have been problems in developing standard sampling methods, in proving a causal relationship and in establishing threshold limit values for exposures due to the complexity of composition of bio-aerosols, variations in human response to their exposure and difficulties in recovering microorganisms. Currently bio-aerosol monitoring in hospitals is carried out for epidemiological investigation of nosocomial infectious diseases, research into airborne microorganism spread and control, monitoring biohazardous procedures and use as a quality control measure. In India there is little awareness regarding the quality of indoor air, mould contamination in indoor environments, potential source for transmission of nosocomial infections in health care facilities. There is an urgent need to undertake study of indoor air, to generate baseline data and explore the link to nosocomial infections. This article is a review on composition, sources, modes of transmission, health effects and sampling methods used for evaluation of bio-aerosols, and also suggests control measures to reduce the loads of bio-aerosols.
  58 28,869 1,844
ORIGINAL ARTICLE
Comparison of the conventional diagnostic modalities, bactec culture and polymerase chain reaction test for diagnosis of tuberculosis
SS Negi, S FB Khan, Sunil Gupta, ST Pasha, S Khare, S Lal
January-March 2005, 23(1):29-33
DOI:10.4103/0255-0857.13869  PMID:15928418
PURPOSE: To evaluate the performance of 65 kDa antigen based PCR assay in clinical samples obtained from pulmonary and extrapulmonary cases of tuberculosis. METHODS: One hundred and fifty six samples were processed for detection of Mycobacterium tuberculosis by ZN smear examination, LJ medium culture, BACTEC radiometric culture and PCR tests. RESULTS: A significant difference was seen in the sensitivities of different tests, the figures being 74.4% for PCR test, 33.79% for ZN smear examination, 48.9% for LJ culture and 55.8% for BACTEC culture (P<0.05). However, there was no significant difference (P>0.05) as far as specificity of different tests was concerned. PCR test sensitivity in pulmonary and extrapulmonary clinical samples were 72.7% and 75.9% respectively and found to be significantly higher (P<0.05) when compared with those of other tests. The mean detection time for M.tuberculosis was 24.03 days by LJ medium culture, 12.89 days by BACTEC culture and less than one day by PCR test. CONCLUSIONS: PCR is a rapid and sensitive method for the early diagnosis of pulmonary and extrapulmonary tuberculosis.
  57 18,326 990
BRIEF COMMUNICATION
Prevalence of methicillin resistant staphylococcus aureus in a tertiary referral hospital in eastern Uttar Pradesh
S Anupurba, MR Sen, G Nath, BM Sharma, AK Gulati, TM Mohapatra
January-March 2003, 21(1):49-51
PMID:17642975
We report the prevalence of methicillin resistant Staphylococcus aureus (MRSA) infections and their antibiotic susceptibility pattern in our hospital located in eastern Uttar Pradesh. Out of total 549 strains of Staphylococcus aureus isolated from different clinical specimens 301 (54.85%) were found to be methicillin resistant. More than 80% of MRSA were found to be resistant to penicillin, cotrimoxazole, ciprofloxacin, gentamicin, erythromycin, tetracycline, 60.5% to amikacin and 47.5% to netilmicin. However, no strains were resistant to vancomycin. Many MRSA strains (32.0%) were multi-drug resistant. To reduce the prevalence of MRSA, the regular surveillance of hospital associated infection, monitoring of antibiotic sensitivity pattern and formulation of definite antibiotic policy may be helpful.
  55 13,885 0
ORIGINAL ARTICLE
In-vitro susceptibility testing by agar dilution method to determine the minimum inhibitory concentrations of amphotericin B, fluconazole and ketoconazole against ocular fungal isolates
KL Therese, R Bagyalakshmi, HN Madhavan, P Deepa
October-December 2006, 24(4):273-279
DOI:10.4103/0255-0857.29386  PMID:17185846
Purpose : To standardize in-vitro antifungal susceptibility testing by agar dilution method to find out the minimum inhibitory concentration (MIC) of amphotericin B, fluconazole and ketoconazole on ocular fungal isolates. Methods: A total of 180 ocular fungal isolates (130 filamentous fungi and 50 yeasts) were included. The antifungal drugs such as amphotericin B (0.0625-8 mg/mL), fluconazole (0.2-819.6 mg/mL) and ketoconazole (0.025-6.4 mg/mL) were incorporated in doubling dilutions in the yeast nitrogen base medium. The MIC was determined as the lowest concentration of the antifungal drug preventing growth of macroscopically visible colonies on drug containing plates when there was visible growth on the drug - free control plates. Results: All 50 ocular isolates of yeast were susceptible to amphotericin B, while two (4%) and five (10%) strains were resistant to fluconazole and ketoconazole respectively. Of the 130 filamentous fungi tested, six (4.6%) were resistant to amphotericin B, 49 (37.7%) and 10 (7.6%) were resistant to fluconazole and ketoconazole respectively. Percentile 50 (MIC 50) and Percentile 90 (MIC 90) for all the three antifungal agents were calculated. Aspergillus niger , Aspergillus terreus and Candida krusei were found to be resistant to fluconazole and ketoconazole. Conclusion: This technique was found to be reliable, cost effective and easy to perform with consistent results.
  53 16,011 1,085
Prevalence and antimicrobial susceptibility pattern of methicillin resistant Staphylococcus aureus: A multicentre study.
K Rajaduraipandi, KR Mani, K Panneerselvam, M Mani, M Bhaskar, P Manikandan
January-March 2006, 24(1):34-38
DOI:10.4103/0255-0857.19892  PMID:16505553
Purpose: Methicillin resistant Staphylococcus aureus (MRSA) is an important nosocomial pathogen. We report the prevalence and antibiotic susceptibility pattern of MRSA in major southern districts of Tamilnadu. Methods: A total of 7172 clinical specimens and 1725 carrier screening samples were collected from different centers and subjected to MRSA screening using conventional microbiological methods. Subsequently the antibiotic sensitivity test was performed for the confirmed MRSA isolates. Results: Out of 906 strains of S. aureus isolated from clinical and carrier samples, 250 (31.1%) and 39 (37.9%) were found to be methicillin resistant respectively. Almost all clinical MRSA strains (99.6%) were resistant to penicillin, 93.6% to ampicillin, and 63.2% towards gentamicin, co-trimoxazole, cephalexin, erythromycin, and cephotaxime. All MRSA strains (100%) of carrier screening samples had resistance to penicillin and about 71.8% and 35.9% were resistant to ampicillin and co-trimoxazole respectively. Multidrug resistance was observed among 63.6% of clinical and 23% of carrier MRSA isolates. However, all strains of clinical and carrier subjects were sensitive to vancomycin. Conclusion: The determination of prevalence and antibiotic sensitivity pattern of MRSA will help the treating clinicians for first line treatment in referral hospitals.
  50 24,171 1,718
REVIEW ARTICLE
Extended spectrum -lactamases (ESBL) - An emerging threat to clinical therapeutics
U Chaudhary, R Aggarwal
April-June 2004, 22(2):75-80
PMID:17642700
Extended spectrum -lactamases (ESBLs) are plasmid mediated, TEM and SHV derived enzymes, first isolated in Western Europe in mid 1980s, most commonly in Klebsiella spp., followed by Escherichia coli. These enzymes are capable of hydrolyzing broad spectrum cephalosporins and monobactams but inactive against cephamycins and imipenem. In addition, ESBL producing organisms exhibit coresistance to many other classes of antibiotics resulting in limitation of therapeutic option. Several risk factors have been suggested. A variety of classification schemes have been developed. Recently, Bush-Jacoby-Medeiros scheme integrated functional and molecular characteristics. ESBLs have serine at their active site and attack the amide bond in the lactam ring of antibiotics causing their hydrolysis. Because of inocolum effect and substrate specificity their detection is a major challenge. Two indicators of ESBLs are eight fold reduction in MIC and potentiation of the inhibitor zone of third generation cephalosporin in the presence of clavulanic acid. Incidence of these organisms is being continuously increasing through out the world with limited treatment alternatives. It becomes necessary to know the prevalence of these organisms and to formulate treatment policy. Moreover, restricted use of the third generation cephalosporins lead to withdrawal of selective pressure and use of lactam and -lactamase inhibitor combinations may exert reverse mutation on these enzymes.
  50 63,765 3,530
BRIEF COMMUNICATION
Prevalence of HBV and HCV dual infection in patients on haemodialysis
GA Reddy, KV Dakshinamurthy, P Neelaprasad, T Gangadhar, V Lakshmi
January-March 2005, 23(1):41-43
DOI:10.4103/0255-0857.13872  PMID:15928421
Hepatitis viral infections are important causes of morbidity and mortality in haemodialysis patients. One hundred and thirty four patients attending haemodialysis unit were screened for the presence of HBV and HCV infections. Eight (5.9%) patients were HCV positive while two (1.4%) patients had HBV infection. A dual infection with both the viruses was observed in five patients (3.7%).
  47 10,632 521
ORIGINAL ARTICLE
Prevalence of extended spectrum -lactamase producing klebsiella pneumoniae in a tertiary care hospital
I Shukla, R Tiwari, M Agrawal
April-June 2004, 22(2):87-91
PMID:17642702
PURPOSE: The purpose of this study was to know prevalence of extended spectrum -lactamase (ESBL) in multi drug resistant (MDR) strains of Klebsiella pneumoniae isolated from different clinical samples. METHODS: A total of 120 MDR strain of K. pneumoniae were selected for the study, 106 of which were resistant to atleast one of the third generation cephalosporins (3GC). They were studied for ESBL production by phenotypic confirmatory disc diffusion test (PCDDT) and by double disc synergy test (DDST). RESULTS: 88.3% (106) of the isolates were found to be resistant to atleast one of the 3GC tested (cefotaxime, ceftazidime and ceftriaxone) and 72% of the isolates were resistant to all the 3GC tested. ESBL was detected in 30.18% (32) of the K. pneumoniae by PCDDT and in 27.3% (29) by DDST. Among the ESBL producers 6 (18.75%) were sensitive to cefotaxime, 2 (6.25%) to ceftazidime and 3 (9.37%) to ceftriaxone by disc diffusion test. The minimum inhibitory concentrations (MICs) of 3GC for these strains ranged from 2-8 g/mL while for non ESBL producer sensitive counterparts it ranged from 0.03-1 g/mL. Resistance to cefotaxime was transferred to recipient E. coli K12 strains J62-1. All the K. pneumoniae isolates were sensitive to imipenem. Resistance against amoxicillin, gentamicin, ciprofloxacin and amikacin was found in 93.28, 70, 10.37 and 26.14% of the isolates respectively. CONCLUSIONS: Our study shows presence of ESBL producer K. pneumoniae in clinical isolates. The routine antimicrobial sensitivity test may fail to detect ESBL mediated resistance against 3GC and detection of ESBL production should be carried out as a routine in diagnostic laboratories by PCDDT as it is a simple and cost effective test.
  44 14,878 1,086
REVIEW ARTICLES
Meningococcal disease: History, epidemiology, pathogenesis, clinical manifestations, diagnosis, antimicrobial susceptibility and prevention
V Manchanda, S Gupta, P Bhalla
January-March 2006, 24(1):7-19
DOI:10.4103/0255-0857.19888  PMID:16505549
Meningoccocal disease has repeatedly caused outbreaks worldwide. There has been sudden surge of cases of meningococcemia and meningococcal meningitis in early 2005 in Delhi, India and neighboring states of Uttar Pradesh and Haryana. As of June 17, 2005, 429 probable cases of meningococcal disease have been reported in Delhi out of which 128 cases have revealed microbiological evidence of Neisseria meningitidis . It is possible that the number of cases was in excess of the numbers notified. During this episode drug susceptibility testing by MIC method (E-test) using break points recently recommended by NCCLS/CLSI, revealed that all isolates were sensitive to penicillin, ampicillin, rifampicin and ceftriaxone. As regards to ciprofloxacin, about two third of the isolates tested were found to be 'non-susceptible' (MIC =0.03g/mL- 0.190g/mL). All the isolates were found resistant to cotrimoxazole (MIC> 16g/mL). Repeated outbreaks, decreased susceptibility to ciprofloxacin, which is commonly used for chemoprophylaxis of meningococcal disease, highlights the need for a constant surveillance system. Present review deals with various aspects of Neisseria meningitidis and meningococcal disease in view of recent episode.
  43 85,406 2,469
REVIEW ARTICLE
Association of Parasitic Infections and Cancers
S Khurana, ML Dubey, N Malla
April-June 2005, 23(2):74-79
DOI:10.4103/0255-0857.16044  PMID:15928434
Recent advances in the fields of molecular biology, epidemiology and infectious diseases have led to significant revelations to clarify the relationship between cancer and infective agents. This article reviews the relationship between parasitic infections and carcinogenesis and the possible mechanisms involved. Few parasites, e.g., Schistosoma haematobium and Opisthorchis viverrini have been found to be strongly associated with bladder cancer and cholangiocarcinoma respectively. The evidence for the association of several other parasites and cancers has also been postulated.
  42 32,672 1,271
BRIEF COMMUNICATIONS
Occurrence of extended spectrum beta-lactamases among Enterobacteriaceae spp. isolated at a tertiary care institute
MS Kumar, V Lakshmi, R Rajagopalan
July-September 2006, 24(3):208-211
PMID:16912442
Increasing resistance to third generation cephalosporins has become a cause for concern especially among Enterobacteriaceae that cause nosocomial infections. The prevalence of extended spectrum β -lactamases (ESBLs) among members of Enterobacteriaceae constitutes a serious threat to current β -lactam therapy leading to treatment failure and consequent escalation of costs. A detailed study was initiated to identify the occurrence of ESBLs among the Enterobacteriaceae isolates at a tertiary care hospital using the double disk potentiation technique. Antibiogram profiles were determined to commonly used antibiotics and confirmation of ESBLs production was carried out by the disk diffusion assay using ceftazidime and cefotaxime in the presence and absence of clavulanic acid. Our results indicate that the majority of ESBLs were expressed in Escherichia coli.
  41 10,465 706
ORIGINAL ARTICLE
Cefoxitin resistance mediated by loss of a porin in clinical strains of Klebsiella pneumoniae and Escherichia coli
S Ananthan, A Subha
January-March 2005, 23(1):20-23
DOI:10.4103/0255-0857.13867  PMID:15928416
PURPOSE: Porins are outer membrane protein (OMP) that form water filled channels that permit the diffusion of small hydrophilic solutes like -lactam antibiotics across the outer membrane. Two major porins that facilitate diffusion of antimicrobials have been described in Klebsiella spp. and Escherichia coli. The present study was carried out to examine the role of porins among Extended Spectrum -Lactamase (ESBL) and AmpC -Lactamase positive strains of Klebsiella spp. and E.coli. METHODS: Preparation of OMP from phenotypically characterized clinical isolates K.pneumoniae and E.coli and the separation of the proteins by sodium dodecyl sulfate - polyacrylamide gel electrophoresis were performed as per a previously described procedure. RESULTS: OMP analysis revealed that cefoxitin and ceftazidime resistance was mediated by loss of a porin Omp K35 in the isolates of K.pneumoniae and E.coli. CONCLUSIONS: Loss of porin mediated resistance mechanism against cefoxitin was observed among the multidrug resistant K.pneumoniae and E.coli.
  40 11,078 561
ORIGINAL ARTICLES
Correlation between biofilm production and multiple drug resistance in imipenem resistant clinical isolates of Acinetobacter baumannii
R Srinivasa Rao, R Uma Karthika, SP Singh, P Shashikala, R Kanungo, S Jayachandran, K Prashanth
October-December 2008, 26(4):333-337
DOI:10.4103/0255-0857.43566  PMID:18974485
Purpose: To study the qualitative and quantitative methods for the investigation of biofilm formation and to examine the correlation between biofilm and antibiotic resistance among the clinical isolates of Acinetobacter baumannii . We also verified the association between biofilm and presence of extended spectrum β-lactamases, particularly, bla PER-1 . Methods: A total of 55 isolates were subjected to susceptibility testing by disc diffusion method for 13 clinically relevant antibiotics. Screening for biofilm production was done by both qualitative and quantitative methods through tube and microtitre plate assay respectively. The presence of bla PER-1 was checked by PCR. Results: A. baumannii isolates showed very high resistance (>75%) to imipenem, cephotaxime, amikacin and ciprofloxacin. Only cefoperazone, netillin and norfloxacin were found to be effective agents. Results of microtitre and tube methods were concordant with 34 isolates (62%) showing biofilm formation. Resistance to four antibiotics such as amikacin (82% vs. 17.6%, P <0.001), cephotaxime (88% vs. 11%, P P <0.001), ciprofloxacin (70% vs. 29%, P =0.005) and aztreonam (38% vs. 11%, P =0.039) was comparatively higher among biofilm producers than non-biofilm producers. Microtitre assay additionally detected 14 weakly adherent isolates. Only 11 isolates had bla PER-1 gene and among these two were strong biofilm producers, while remaining were weakly adherent isolates. Conclusion: Microtitre plate method was found to be a more sensitive method for biofilm detection. This study demonstrates a high propensity among the clinical isolates of A. baumannii to form biofilm and a significant association of biofilms with multiple drug resistance. Presence of bla PER-1 appears to be more critical for cell adherence than for biofilm formation.
  39 13,900 1,542
BRIEF COMMUNICATIONS
Study of onychomycosis: Prevailing fungi and pattern of infection
P Veer, NS Patwardhan, AS Damle
January-March 2007, 25(1):53-56
DOI:10.4103/0255-0857.31063  PMID:17377354
A mycological study of onychomycosis was undertaken in 88 patients. The nails were judged to be infected by their clinical appearance. Direct microscopy of the nail clips in 20% KOH solution was positive in 72 (81.8%) and culture was positive in 43 (48.8%) cases. Out of the samples cultured, dermatophytes were grown in 26 cases (29.5%), non dermatophyte moulds in 12 (13.6%) and Candida spp. in 5 (5.6%) while 45 (51.1%) samples yielded no growth. Amongst dermatophytes, T. rubrum was found to be commonest etiological agent (57.6%) followed by T. mentagrophyte . Amongst the non-dermatophyte mould (NDM), Aspergillus spp. was the most prevalent species followed by Alternaria spp, Curvularia spp. and Fusarium spp. Commonest age group affected was above 31 years. Males were predominantly affected (65%), male to female ratio being 1.8:1. Fingernails were affected more frequently than toe nails with the ratio of 3:1. Distal and lateral subungual onychomycosis (DLSO) was more common (50%) than other clinical pattern followed by proximal subungual onychomycosis (PSO) (20.4%), white superficial onychomycosis (SWO) (2%), total dystrophic onychomysosis (TDO) (14%) and paronychia (10.2%).
  37 14,184 1,396
ORIGINAL ARTICLE
Effect of azadirachta indica (neem) on the growth pattern of dermatophytes
V Natarajan, PV Venugopal, T Menon
April-June 2003, 21(2):98-101
PMID:17642990
PURPOSE: To determine the minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) for the extracts of the leaves and seeds of the plant Azadirachta indica against various dermatophytes. METHODS: Clinical isolates of dermatophytes(Trichophyton rubrum, Trichophyton mentagrophytes and Microsporum nanum) were treated with extracts of leaves and seeds of the plant Azadirachta indica (neem) for antifungal activity by in vitro tube dilution technique. RESULTS: The MIC of neem seed extracts was 31g/mL for all the dermatophytes tested. The neem seed extract at 15g/mL concentration (below MIC) was observed to be sufficient for distorting the growth pattern of the organisms tested. CONCLUSIONS: The changes in growth curve of the treated dermatophytes were found to be statistically significant with reference to the untreated fungi.
  37 20,976 979
SPECIAL ARTICLES
Serum levels of bcl-2 and cellular oxidative stress in patients with viral hepatitis
HG Osman, OM Gabr, S Lotfy, S Gabr
October-December 2007, 25(4):323-329
DOI:10.4103/0255-0857.37333  PMID:18087079
Purpose: This study was conducted to investigate the presence of bcl-2 protein in the serum of patients with viral hepatitis and to find out if there is any correlation between bcl-2 protein levels and cellular oxidative stress in the pathogenesis of viral hepatitis. Methods: This study was carried out on 130 patients with viral hepatitis, 70 with chronic hepatitis, 30 with liver cirrhosis and 30 with hepatocellular carcinoma (HCC) in addition to 20 healthy persons as the control. Serum bcl-2 protein was estimated by enzyme-linked immunosorbent assay, serum malondialdehyde (MDA), nitric oxide (NO) and antioxidant enzymes (GSH, GSH-px, GR and SOD) were measured using spectrophotometric analysis. Results: bcl-2 protein level was significantly elevated in the serum of HCC, cirrhosis and chronic hepatitis groups as compared to control group. There were significant positive correlations between higher bcl-2 protein level and viral hepatitis markers (HBsAg, anti-HCV antibodies) in HCC and cirrhotic patients as compared to chronic hepatitis group. An increase in oxidative stress markers (MDA, NO) and a decrease in antioxidant enzyme activities (SOD, GSH and GSH-px) were observed. However, there was a negative correlation between bcl-2 levels and GR in all studied patient groups. Conclusions: The release of oxidative free radicals, deficiency in antioxidant enzymes and the expression of bcl-2 protein might play a role in the pathogenesis of viral hepatitis. The ability to measure bcl-2 protein in the serum could be useful as a prognostic marker of cancer patients.
  37 6,638 496
* Source: CrossRef

2004 - Indian Journal of Medical Microbiology
Published by Wolters Kluwer - Medknow

Online since April 2001, new site since 1st August '04