After the discovery of human immunodeficiency virus (HIV) and its role in the causation of most devastating epidemic acquired immune deficiency syndrome (AIDS), there has been an increasing trend to decipher the mechanism of infection and to understand why it cannot be controlled by our immune system. By evolution, our immune system has been empowered and enough trained to recognize, elicit immune response and remove antigens and pathogens from the body. Simultaneously, HIV has also gained enough mechanism to escape the natural immune response. On one hand, it downregulates HLA class I antigens, which may present viral antigens to specific CD8 ⁺ T cells; on the other hand, the viral genome get mutated very readily under the selection pressure of specific cytotoxic T lymphocytes. The high mutation rate and convertibility of its genotype makes it a moving target and poses a prime hurdle in vaccine development. This review explains how HIV enters into the cell, how it resists the host immune response and how HIV manages to escape from it and establish in the human body.

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.

Purpose: The non-sporing anaerobes cause a wide spectrum of infections. They are difficult to culture and their identification is tedious and time-consuming. Rapid identification of anaerobes is highly desirable. Towards this end, the potential of nuclear magnetic resonance (NMR) spectroscopy for providing a fingerprint within the proton spectrum of six genera belonging to anaerobes reflecting their characteristic metabolites has been investigated. Methods: NMR analysis was carried out using Mercury plus Varian 300 MHz (7.05 T) NMR spectrophotometer on six different anaerobes. These included Bacteroides fragilis, Prevotella melaninogenica, Prevotella denticola, Fusobacterium necrophorum, Peptococcus niger and Peptostreptococcus spp. After the NMR analysis (256/512 scans), the different peaks were noted. The eight pus specimens, which yielded pure culture of anaerobe, also were analysed similarly. Results: The major resonances of multiplex of amino acids/lipid at 0.9 ppm along with lactate/lipid at 1.3 ppm, acetate at 1.92 ppm and multiplex of lysine at 3.0 ppm remained constant to label the organism as an anaerobe. There was a difference found in the MR spectra of different genera and species. A simple algorithm was developed for the identification of the six different anaerobes studied. The MR spectra of the pure culture of the organism matched the MR spectra of pus from which the organism was isolated. Conclusions: MR-based identification was of value in the identification of anaerobes. However, a larger database of the peaks produced by anaerobes needs to be created for identification of all genera and species. It could then have the potential of diagnosing an anaerobic infection in vivo and thus expedite management of deep-seated abscesses.

Background: Various reports on distribution of Acinetobacter spp. from healthy human skin restricted to urban population. However, no such data is available from healthy human skin of tribal population not exposed to modern antibiotics during their life time. Purpose: Isolation, biotyping, distribution and physiological characterisation of Acinetobacter spp. from healthy human skin of tribal population. Methods: Tribal population of Toranmal area of Satpuda Ranges, Maharashtra, India were sampled for ten body sites. Tentative Acinetobacter isolates were confirmed to the genus level by chromosomal DNA transformation assay and to species level using Bouvet and Grimont system. Novel physiological characteristics like pH, temperature and salt tolerance were studied. All strains were screened for production of various enzymes. Results: One hundred and eighteen strains were isolated, which belonged to nine Acinetobacter genospecies. A. haemolyticus was most abundant followed by A. calcoaceticus and A. genospecies 1-3. Higher percentage of Acinetobacter was recovered from skin of nose, Pawara tribe and female volunteers. They showed wide variation in temperature, salt and pH tolerance. Most of the strains could produce enzymes viz, lipase, esterase, urease and amylase. Conclusions: Acinetobacter spp. belonging to nine genospecies were obtained in the present study. Physiological characteristics including high salt, temperature and acidic pH tolerance were helpful to differentiate between the commensal and pathogenic species of Acinetobacter genus.

Purpose: To study the prevalence of TEM-, SHV- and GES-type β -lactamases among Escherichia coli and Klebsiella pneumoniae strains having ceftazidime MICs higher than 2 mg/L. Methods: A total of 63 E. coli and 41 K. pneumoniae isolated from five different university hospitals were studied for the existence of TEM-, SHV- and GES-type β -lactamases. Susceptibility tests were carried out according to the criteria of National Committee for Clinical Laboratory Standards. MICs were obtained by agar dilution method. Existence of extended-spectrum β -lactamases (ESBLs) were assessed by double-disc synergy test (DDST). Existence of the above-mentioned β -lactamase genes were studied both by PCR with specific oligonucleotide primers and isoelectric focusing methods. Results: None of the isolates were carbapenem-resistant. DDSTs were positive in 50 (79.3%) and 33 (80.5%) of E. coli and K. pneumoniae , respectively. TEM gene was detected in 41 (65.1%) and 19 (46.3%), whereas SHV gene in 18 (28.6%) and 20 (48.8%) of E. coli and K. pneumoniae strains, respectively. GES genes were not detected. Conclusions: TEM and SHV genes are highly prevalent among ESBL-producing E. coli and K. pneumoniae , whereas GES-type ESBLs are absent and found not to be responsible of ceftazidime resistance in Turkish hospitals.

Purpose: The aim of the present study was to evaluate the major source of increased serum enzyme level in typhoid fever and to determine the most relevant clinical entity, hepatitis or myopathy, during typhoid fever. Methods: A total of 118 subjects proved to have typhoid fever were evaluated for serum enzymes such as transaminases, alkaline phosphatase, lactate dehydrogenase (LDH) and creatinine kinase (CK); and their relation with each other, clinical symptoms and serum bilirubin were evaluated by regression methods. Results: Hepatomegaly was revealed in 14% of the cases and was correlated with elevated serum biliribin (5.05 ± 13.03 mg/dL in hepatomegalic subjects). Alanine aminotransferase (ALT) and CK were elevated in 22 and 60% of the cases, respectively. Correlation coefficient of CK with aspartate aminotransferase (AST) and LDH was R 2 = 0.68 and 0.75, respectively, which were higher than that of ALT with that two enzymes. Conclusions: In conclusion, elevation of serum enzymes in typhoid is mostly of muscular origin.

Purpose: This prospective study was carried out to determine the antimicrobial susceptibility of Neisseria gonorrhoeae isolates by disc diffusion method and minimum inhibitory concentration (MIC) by E -test with special reference to azithromycin. Also, the correlation between in vitro susceptibility and treatment outcome with single 2 g oral dose azithromycin was assessed. Methods: The study included 75 gonococcal isolates from males with urethritis, females with endocervicitis and their sexual contacts. All isolates were subjected to susceptibility testing for penicillin, ciprofloxacin, tetracycline, ceftriaxone, spectinomycin, cefixime and azithromycin. Males with gonococcal urethritis were randomised to receive a single dose of either azithromycin or ceftriaxone. Forty-two men with urethritis received 2 g single oral dose azithromycin, while all other patients were given 250 mg parentral ceftriaxone. All patients were called for follow-up to assess clinical and microbiological cure rates. Results: While all the isolates were susceptible to ceftriaxone, spectinomycin, cefixime and azithromycin; 74 (98.7%), 24 (32%) and 23 (30.7%) strains were resistant to ciprofloxacin, penicillin and tetracycline respectively, by both disc diffusion method and E -test. The MIC range, MIC ₅₀ and MIC ₉₀ of N. gonorrhoeae strains, to azithromycin were 0.016-0.25, 0.064 and 0.19 mg/mL, respectively. Follow-up attendance of the patients was 52.4 with 100% clinical and microbiological cure rates. Conclusions: Results of our study indicate that 2 g single oral dose azithromycin is safe and effective in the treatment of uncomplicated gonorrhoea.

Purpose: This study compares the results of radiorespirometric Buddemeyer assay with adenosine triphosphate (ATP) assay and mouse foot pad (MFP) test to validate the sensitivity of Buddemeyer assay in detecting viable M. leprae in clinical samples. Methods: Viability was assessed using all the three methods in 60 skin biopsy specimens, including 20 untreated lepromatous leprosy (BL-LL), 13 treated BL-LL, 12 untreated borderline tuberculoid to mid borderline (BT-BB) and 15 treated BT-BB cases. Results: Of the 20 untreated BL-LL cases tested, positivity indicating the presence of viable M. leprae was detected in 85, 60 and 85% with Buddemeyer, ATP and MFP test, respectively. Among the 13 treated BL-LL cases, scores were 61, 54 and 0%; among the 12 untreated BT-BB cases, the scores were 58, 16 and 16% and among the 15 treated BT-BB cases, the scores were 46, 20, 0%, respectively. Conclusion: The detection sensitivity (positive scores) with three tests were closely comparable in the two untreated groups of cases. On the other hand, in the two treated groups, a good proportion of cases scored positive in the in vitro tests but none in the MFP test. Among the two in vitro methods, the Buddemeyer assay emerged as a better test, in terms of sensitivity and specificity.

Purpose: A two-stage nested polymerase chain reaction (PCR) assay system was described that amplifies the 16S-23S rRNA spacer region sequences of Mycoplasma and Acholeplasma infections in cell cultures and virus stocks. Methods: Established cell lines and virus stocks were screened for the presence of Mycoplasma by using nested PCR using two sets of outer and inner primers, amplifies 16S-23S rRNA. PCR and restriction fragment length polymorphism (RFLP) assay was used to detect and identify most of the species-specific Mycoplasmas involved in cell cultures and virus stock contaminants. Infected cultures detected by PCR-RFLP were further treated with BM-cyclin (5 μg/mL) and passaged for three times and tested for Mycoplasma infections by PCR-RFLP. Results: Mycoplasma pirum and Mycoplasma orale infections were detected by nested PCR. Species specificity was identified by using RFLP of Vsp I, Cla I and Hin dIII restriction enzymes. Mycoplasma infections were cured by treatment with BM-cyclin. This was further confirmed by non-amplification of PCR amplimers in BM-cyclin treated vs. non-treated cultures. Conclusions: Regular monitoring of cell cultures for Mycoplasma infections and identification of species-specific Mollicutes will identify the source of contaminations. This approach can be used for quality control of the biological reagents used in cell culture and virology laboratories.

Purpose: To determine the virulence factors produced by Escherichia coli isolated from extraintestinal infections, to study the drug resistance pattern in E. coli with special reference to extended spectrum β -lactamase (ESBL) and to evaluate screening methods for ESBL. Methods: A total of 152 isolates of E. coli from various extraintestinal infections were screened for virulence factors such as haemolysin, surface hydrophobicity, serum resistance and protease. All the isolates were also studied for antibiotic susceptibility pattern using modified Kirby Bauer disk diffusion method. ESBL production was screened by standard disk diffusion method and confirmed using phenotypic confirmatory method. Results: Among 152 isolates, 36 (23.7%) were haemolytic, 42 (27.6%) were hydrophobic, 132 (86.8%) were serum resistant and only four were positive for protease. Multiple virulence factor were observed in 67 (44%) of isolates. Seventy-nine (51.4%) isolates produced ESBL. ESBL producing isolates showed multidrug resistance. There was a significant association ( P < 0.001) between multiple virulence factors and ESBL production by extraintestinal E. coli . Conclusions: The present study shows the expression of virulence factors and multidrug resistance in E. coli isolated from various extraintestinal infections. The study also shows that appropriate methods of detecting drug resistance and ESBL production are required for the judicious use of antibiotics in managing these infections.

Purpose: To assess the pattern of antimicrobial susceptibility profile of Helicobacter pylori isolates from patients with gastritis, duodenal ulcer (DU) and gastroesophageal reflux disease (GERD) residing in Shiraz, Iran. Methods: One hundred and six H. pylori isolates from patients with gastritis, DU and GERD undergoing endoscopy at our university hospitals and clinics were analysed for their antimicrobial susceptibility to metronidazole, clarithromycin, amoxicillin, co-amoxiclav, tetracycline, ciprofloxacin and furazolidone. The minimum inhibitory concentrations were determined by agar dilution method. Results: Overall H. pylori resistance rate was 72.6% to metronidazole, 9.4% to clarithromycin and furazolidone, 20.8% to amoxicillin and 4.7% to tetracycline and ciprofloxacin. No resistance to co-amoxiclav was detected among H. pylori isolates. No significant differences between antimicrobial resistance and clinical outcome were detected. Conclusions: With regard to the increasing resistance of H. pylori isolates to various antibiotics, susceptibility testing of H. pylori isolates prior to the treatment of infection must be performed to achieve better eradication and to reduce the risk of selection of H. pylori resistant strains.

Purpose: A waterborne outbreak of viral hepatitis occurred in the old city of Hyderabad from March through August 2005. An attempt was made to study the outbreak clinically, serologically, and etiologically. Methods: Five hundred and forty-six clinically and biochemically documented cases were screened for the hepatotropic viral markers, hepatitis A, B, C, and E by the ELISA method. Their demographic characteristics and outcomes were analyzed. Point source contamination of the water supply with sewerage was identified. Result: Our data confirms hepatitis E as the major cause of the outbreak (78.57%). Occasionally, mixed infection of HEV-HAV (5.31%) or HEV-HBV (0.91%) was detected in the present series of acute viral hepatitis. Conclusions: HEV was confirmed as the major etiological agent in this outbreak that was transmitted by contaminated drinking water. The study highlights the importance of screening for both enterically transmitted hepatotropic viral markers as well as the parenterally transmitted hepatotropic viral markers during outbreaks of acute viral hepatitis.

Purpose: To compare BACTEC MGIT 960 (M960) with conventional culture on Lowenstein Jensen (LJ) media and direct acid fast bacilli (AFB) smear examination for the detection of Mycobacteria in clinical samples obtained from suspected cases of pulmonary and extra pulmonary tuberculosis (TB). Methods: A total of 500 samples were processed for direct AFB smear examination, and culture on M960 and LJ media. Results: Two hundred fifty-eight out of 500 (51.6%) isolates of Mycobacteria were obtained by combined use of the two culture methods. Two hundred and fifty-three (50.6%) were positive in culture by M960 and LJ media and 28% (140/500) by direct AFB smear examination. The positivity rate of M960 system alone was 34.10% (88/258) and of LJ alone was 1.93% (5/258). Average time to detect growth (TTD) was 9.66 days by M960 and 28.81 days by LJ. Conclusions: M960 system is a rapid and sensitive method for early diagnosis of pulmonary and extrapulmonary TB. But for maximum recovery of Mycobacteria , a combination of both M960 and LJ media should be used.

Purpose: To determine the serum levels of proinflammatory and some of the Th1/Th2 cytokines in brucellosis and their alterations with treatment and outcome. Methods: Twenty-eight acute and seven subacute brucellosis patients diagnosed clinically were included in the study. Twenty healthy volunteers were also included. Brucella standard tube agglutination tests and blood culture were conducted on all subjects. Cytokine levels of pre- and post-treatment period serum samples were measured by ELISA. Results: The mean serum levels of IL-6, IFN-g and TNF-a were significantly higher in brucellosis patients compared to the control group ( P < 0.05). No significant differences were found between patient and control groups in terms of IL-1β , TGF-β 1, IL-2, IL-4 and IL-8 levels. There was a positive correlation between IFN-γ, TNF-α and IL-6 levels with CRP levels. IL-6, IFN-γ and TNF-α levels measured after treatment were statistically significantly lower than pre-treatment values ( P < 0.001). No differences were found in the levels of these cytokines between acute and subacute patients' sera. IL-6, IFN-γ and TNF-α levels were higher in acute or subacute brucellosis patients. Conclusions: Although the levels of the cytokines were decreased significantly with effective and adequate treatment these alterations did not correlate with the extent or activity of the disease.

Fluorescent in situ hybridization (FISH) was carried out using two different oligonucleotide probes specific for Pseudomonas spp. and Acinetobacter spp. These probes were tested against different organisms and were found to be highly specific. Sensitivity testing showed that the probes were able to detect as low as 10 ³ CFU/mL. In addition, FISH was carried out directly on positive blood culture samples and the detection of microorganisms took less than 2 h. We believe that FISH is a rapid method that can be used as a routine laboratory diagnostic technique for the detection of Acinetobacter spp. and Pseudomonas spp. in clinical samples.

The present study aimed to review the results of microscopic examination, routine culture and antigen detection by latex particle agglutination test (LPAT), in order to evaluate the diagnostic value of the LPAT in establishing the aetiological diagnosis of bacterial meningitis. LPAT was done in 65 clinically suspected meningitis cases ranging from 5 days to 60 years of age and was compared with culture and Gram stain. Using LPAT, an aetiological diagnosis could be done in 10 out of 65 (15.4%) cases of bacterial meningitis. In contrast, Gram stain and culture showed 16.9 and 23.1% positivity, respectively. LPAT correlated well with Gram stain and culture and can be recommended as an adjunct laboratory test for rapid aetiological diagnosis of bacterial meningitis for prompt institution of proper antibiotics.

The present study deals with the investigation of the frequency of intestinal helminth parasites in children of Kupwara, Kashmir, India. Three hundred and twelve children in the age group of 4-15 years were examined for different intestinal helminths in three schools located in rural areas. Two hundred and twenty two of 312 (71.15%) tested positive for various intestinal helminths. The various helminth parasites included Ascaris lumbricoides , Trichuris trichiura , Enterobius vermicularis and Taenia saginata . By far, the highest frequency of 69.23% (216/312) was noted for Ascaris lumbricoides followed by Trichuris trichiura 30.76% (96/312), Enterobius vermicularis 7.69% (24/312) and Taenia saginata 7.69% (24/312). Single infection was found in 33.65% (105/312) and mixed infection was seen in 37.5% (117/312) children. This study emphasizes the need for improved environmental conditions, i.e., clean water supplies, enhanced sanitation and chemotherapy of school-age children in rural areas.

This study examined the extent of cryptococcosis in clinically diagnosed cases of meningitis in HIV-1 seropositive and apparently immunocompetent patients. One hundred and forty-six samples, obtained from 126 chronic meningitis patients comprised of cerebrospinal fluid (CSF), blood, sputum and urine. The samples were processed by standard microbiological procedures. Cryptococcal isolates were identified by microscopy, cultural characteristics, melanin production on niger seed agar and hydrolysis of urea. The isolates were further speciated on cannavanine glycine bromothymol blue (CGB) media. Cryptococcal antigen detection of CSF samples was performed by latex agglutination test (LAT). Minimum inhibitory concentration (MIC) of amphotericin B for the isolates was also tested. Cryptococcosis was diagnosed in 13 patients (eight HIV-1 seropositive and five apparently immunocompetent). Cryptococcus neoformans var. neoformans was the predominant isolate. Cryptococcal antigen was detected in all, whereas microscopy could detect yeast cells in nine patients. The isolates were sensitive to amphotericin B. CD4 cell counts ranged from 8 to 96/cu mm. The study concludes that all CSF samples with clinical diagnosis of subacute and chronic meningitis should be subjected to tests for detection of Cryptococcus in clinical laboratory irrespective of the immune status.

This study was conducted to determine the frequency of different Candida spp. isolated from different parts of the hospital, associated risk factors and mortality rate. A total of 59 cases were selected for prospective analysis over a period of one and half years. Blood samples collected were processed by BACTEC (9240) method. Candidaemia was diagnosed by positive blood culture at least from two blood culture samples or from a clinically significant single blood culture sample. Candida spp. were identified by standard techniques. Most frequent isolates were C. tropicalis (35.6%), C. parapsilosis (28.8%), C. glabrata (11.9%) and C. pelliculosa (11.9%). Candida albicans was isolated only in 3.4% cases. Neonatology department accounted for highest number of isolates (27.1%), followed by gastrointestinal surgery (15.3%) and cardiac surgery (13.6%). Mortality was noted in 16.9%. Probable risk factors determined were intensive care unit stay (74.6%), antibiotic therapy (50.8%), central line (42.4%), urinary catheter (32.2%), ventilator (23.7%), malignancy (20.3%) and abdominal surgery (15.3%).

E. sakazakii has been implicated in necrotizing enterocolitis, bloodstream and central nervous system infections, with mortality rates of 40-80%. Two cases of E. sakazakii infections; one preterm very low birth weight neonate with meningitis and a two month infant with bacteraemia, are described for the first time in India. The first baby succumbed to the infection while the other responded to appropriate therapy. Powdered infant milk formulae have been implicated in causing neonatal infections and the first baby was on formula feed with classic signs of sepsis and meningitis. The second infant was on breast feed and probably developed nosocomial E. sakazakii bacteraemia.

Toxocariasis is an important zoonotic disease caused by the second stage larva of Toxocara canis or Toxocara cati . The typical clinical syndromes of toxocariasis in humans are visceral and ocular toxocariasis. Ocular toxocariasis may presents as peripheral inflammatory mass, posterior pole granuloma and endophthalmitis. We report a serologically confirmed case of ocular toxocariasis in 12-year-old female. The diagnosis was confirmed by detection of anti- Toxocara antibodies in aqueous and vitreous sample by enzyme-linked immunosorbent assay. We suggest that ophthalmologist in this region should include ocular toxocariasis in differential diagnosis particularly in children and young adults.

Cutaneous actinomycosis is a rare presentation. Here we present a case of cutaneous actinomycosis with no history of trauma or systemic dissemination. The isolate was identified as Actinomyces viscosus by standard methods. The isolate was found to be penicillin resistant by Kirby Bauer disc diffusion method. Therefore, the patient was treated with cotrimoxazole and improved. Thus, this case highlights the importance of isolation and susceptibility testing in actinomycotic infection. The sinuses have healed, and the patient has recovered.

Haemophagocytic syndrome (HPS) secondary to infections occurs due to excessive, non-malignant proliferation of histiocytes, with resultant haemophagocytosis. The syndrome is essentially treatable, provided timely etiological diagnosis is achieved. In this report, we present a rare case of a child who hailed from Uttaranchal and presented with severe hepatitis. Bone marrow examination revealed an unexpected diagnosis of HPS secondary to visceral leishmaniasis. Despite initiating appropriate antileishmanial treatment, the child had a fatal outcome.

We describe a case of mucormycosis of median sternotomy wound caused by Rhizopus arrhizus . The patient, a known diabetic and a case of coronary artery disease underwent coronary artery bypass surgery. In the postoperative period, patient developed infection of the median sternotomy wound, from which R. arrhizus was isolated on culture. Patient succumbed in spite of being treated with surgical debridement and amphotericin B. To the best of our knowledge, this is the first reported case of mucormycosis of median sternotomy wound from India.

We report a case of mycobacterial keratitis characterized by apparently spontaneous onset, delayed diagnosis, and eventually necessitating evisceration inspite of systemic antibiotics and repeated corneal grafts.