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A Ayyagari

Publications and source records attributed to A Ayyagari.

At least 37 records · Page 2Linked to original sources
PubMed1999

Role of yeasts as nosocomial pathogens & their susceptibility to fluconazole & amphotericin B.

A total of 213 and 208 yeasts were isolated as nosocomial pathogens from various infected specimens during 1996 and 1997 respectively. Yeasts ranked fifth among uropathogens in both the years and from eighth to eleventh in other specimens. Increasing trend in nosocomial urinary tract yeast infection (11.9 in 1996 to 12.6 in 1997) and decreasing trend in wound and other infections (5.1 in 1996 to 2.9 in 1997) per 1000 patients' discharges were observed; blood stream infection remained unchanged (2/1000 discharges) in both the years. Eighty two (41 from each year) randomly selected yeasts were identified to species level following standard protocol and tested for antifungal susceptibility against fluconazole and amphotericin B by reference broth macrodilution technique and agar dilution (AD) method. The frequency of various yeast species identified was Candida albicans 39 (47.6%), C.tropicalis 29 (35.4%), C. krusei 4 (4.9%), C. glabrata 3 (3.7%), C. zeylanoides 2 (2.4%), C. guilliermondii 2 (2.4%), one strain (1.2%) each of C. kefyr, C. parapsilosis, and Trichosporon beigelii. Resistance to fluconazole (MIC > or = 64 micrograms/ml) as per NCCLS criteria was observed in 2 Candida sp. (2.4%). Significantly higher number of non-albicans Candida sp. (8/43; 18.6%) had MIC > 8 micrograms/ml as compared to C. albicans (2/39; 5.1%) (P < 0.05). Only one strain of C. tropicalis had MIC 8 micrograms/ml to amphotericin B and none had MIC > 8 micrograms/ml. Agreement between the reference and the AD methods for fluconazole was 88 per cent and for amphotericin B was 94 per cent. The present study indicates that Candida sp. are emerging as important nosocomial pathogens and the tendency of yeasts to develop resistance to antifungal agents appears to be a challenge for patient management.

Amphotericin B↗
PubMed1998

Raised IgM antibodies to parvovirus B19 in juvenile rheumatoid arthritis.

To delineate the role of human parvovirus B19 in the etiopathogenesis of juvenile rheumatoid arthritis (JRA), IgM and IgG antibodies specific for parvovirus B19 surface protein antigen(s) were estimated in the sera using commercial ELISA kits. Sera of 69 JRA patients (median age 16 yr, male : female ratio 1.1:1) satisfying the criteria of American Rheumatism Association along with 26 sera of rheumatoid arthritis (RA) and 12 sera of healthy children as disease and normal controls respectively were screened. Of the 69 patients with JRA, 19 (27.5%), 35 (50.7%) and 9 (13%) were positive for IgM, IgG and both IgG and IgM antibodies respectively. Of the 26 disease control sera, 11 (42.3%) were positive for IgG antibodies while none had elevated IgM antibodies. Among 12 healthy controls, 7 (58.3%) were positive for IgG and 1 was positive for both IgG and IgM antibodies. Thus, a statistically significant proportion of children with JRA had evidence of parvovirus B19 infection.

Adolescent↗
PubMed1998

Effect of bacterial association on virulence of Entamoeba histolytica to baby hamster kidney cell monolayers.

Axenic E. histolytica trophozoite strain NIH:200 and HMI:IMSS when co-associated with aerobic bacteria Escherichia coli strain K12 and serotype 056 showed marked increase in virulence as observed by destruction of baby hamster kidney (BHK) monolayers. However, when incubated with anaerobic bacterial strains Clostridium perfringens and Bacteroides fragilis virulence remained unaltered. Further, adherence of E. histolytica to BHK monolayer was found to be mediated by N-acetyl-D-galactosamine.

Acetylgalactosamine↗
PubMed1997

Is undifferentiated seronegative spondyloarthropathy a forme fruste of reactive arthritis?

Undifferentiated spondyloarthropathy (USpa) may either represent a forme fruste of other spondyloarthropathies like reactive arthritis or be a different disease entity. To study the link between USpa and reactive arthritis, we studied the presence of IgA antibodies to Yersinia enterocolitica, Salmonella typhimurium, Shigella flexneri, Campylobacter jejuni and Chlamydia trachomatis in sera from 14 patients with USpa (European Spondyloarthropathy Study Group criteria) using ELISA. Escherichia coli was used as a control antigen. An OD value of more than the mean +/- 2 S.D. of 51 blood donors was considered positive. Five patients had elevated IgA antibodies to S. flexneri, while two patients each had elevated antibody levels to S. typhimurium and Chlamydia. No patient had elevated antibodies to Y. enterocolitica, C. jejuni and E. coli. Among 51 normals, 1, 4, 3, 2 and 3 had elevated antibodies to S. flexneri, S. typhimurium, Y. enterocolitica, C. jejuni and E. coli, respectively. Nine of 14 patients with USpa had antibodies to one of the bacteria implicated in reactive arthritis: of these, antibodies to Shigella were the most frequent. Thus, a proportion of patients with USpa may in fact have reactive arthritis.

Adolescent↗
PubMed1997

Rapid identification of Campylobacter jejuni strains by polymerase chain reaction & their restriction fragment length polymorphism analysis.

A polymerase chain reaction (PCR) technique was developed for specific identification of C. jejuni. A primer pair of a conserved region of flagellin A (fla A) gene identified all 15 strains of C. jejuni isolated from human faeces. None of the control strains like Helicobacter pylori, Vibrio cholerae Escherichia coli and Salmonella typhimurium except C. coli exhibited any amplified product by PCR. A predicted 450 bp could also be amplified from 4 chicken caecal contents positive for C. jejuni-C coli by culture. The caecal contents remained positive for C. jejuni-C. coli by PCR after preservation at 4 degrees C for one week when no viable organism could be detected. Restriction fragment length polymorphism analysis (RFLP) of fla A amplified product by using Bgl II enzyme classified 15 strains into 5 types. Three C. jejuni strains isolated from the same patient over a period of 3 wk showed the same RFLP pattern. The present study indicates that PCR is specific for C. jejuni-C. coli and it has the potential for rapid diagnosis of infection. RFLP can be a good epidemiological marker for C. jejuni infection.

Campylobacter jejuni↗
PubMed1997

The effect of in vitro bacterial association on virulence of Entamoeba histolytica.

When trophozoites of axenic E. histolytica strains NIH : 200 were associated in vitro with Escherichia coli K12 for three hours at 37 degrees C, the virulence was enhanced as shown by increased cytopathogenicity to baby hamster kidney (BHK) cell monolayer. Further, the trophozoites were observed to adhere to the polystyrene surface, a hitherto unreported phenomenon. The co-association of E. histolytica trophozoites with Bacteroides fragilis and Clostridium perfringens for three hours duration at 37 degrees C neither led to increase in cytotoxicity potential nor to adherence phenomenon; in contrast significant inhibition of cytotoxicity was observed. We have thus shown that while co-association of E. histolytica (NIH : 200) with E. coli K12 leads to enhanced amoebic virulence, that with anaerobic bacteric leads to its inhibition.

Animals↗
PubMed1997

Does Entamoeba histolytica cause irritable bowel syndrome?

BACKGROUND: Symptoms of patients with irritable bowel syndrome (IBS) closely mimic those of patients with non-dysenteric amebic colitis. AIM: To examine the clinical relevance of presence and types of Entamoeba histolytica in stools of patients with IBS. METHODS: IBS was diagnosed by Manning's criteria. Stool examination was done 4-weekly for 48 weeks to detect E. histolytica cysts or trophozoites. Patients underwent initial sigmoidoscopy. Sera of 22 IBS patients, 23 asymptomatic cyst passers and 36 healthy volunteers whose stools were also examined were tested for presence of antiamebic antibodies. Stools were cultured for amebae; positive cultures were subjected to polyacrylamide-gel electrophoresis (PAGE) using hexokinase (HK) isoenzyme to distinguish between pathogenic (fast-moving band) E. histolytica infection and nonpathogenic (slow band) species of Entamoeba dispar. RESULTS: E. histolytica cultured from stool samples of four IBS patients had slow-moving band of HK on PAGE. All patients spontaneously eradicated the infection during the next eight to 24 weeks; all had negative serology for antiamebic antibodies, and normal rectal mucosa on sigmoidoscopy. No change in symptom score occurred on follow up in IBS patients, although all of them cleared the infection. Three additional E. histolytica isolates from IBS patients obtained from another laboratory also showed nonpathogenic isoenzyme pattern. CONCLUSION: Bowel symptoms in IBS patients were not related to E. histolytica infection. The term non-dysenteric amebic colitis thus appears to be inappropriate, since it may be used erroneously for patients with IBS with nonpathogenic ameba, leading to injudicious treatment with antiamebic drugs.

Abdominal Pain↗
PubMed1996

Portal hypertensive gastropathy in children with extrahepatic portal venous obstruction: role of variceal obliteration by endoscopic sclerotherapy and Helicobacter pylori infection.

We aimed to determine the frequency of portal hypertensive gastropathy (PHG) in children with extrahepatic portal venous obstruction (EHPVO) and to find out the role of esophageal variceal obliteration by endoscopic injection sclerotherapy (EIS) and Helicobacter pylori (H. pylori) infection in the pathogenesis of PHG. Twenty consecutive children were studied before EIS and 20 after esophageal varices obliteration. Diagnosis of PHG was established by endoscopic assessment. Helicobacter pylori infection was diagnosed by rapid urease test, H. pylori culture, smear, and histopathologic examination of antral biopsy specimens. Portal hypertensive gastropathy was characterized and graded by endoscopy according to previously established criteria. In the pre-EIS group, eight (40%) had PHG (mild in all) compared with 16 (80%; mild in eight, severe in eight) in the post-EIS group (p < 0.05). Portal hypertensive gastropathy was more extensive in the post-EIS group. There was no significant difference between frequency of gastric varices and H. pylori infection in the pre-EIS and post-EIS groups. We conclude that PHG is common in children with EHPVO; its frequency, extent, and severity increase after esophageal variceal obliteration by EIS, and H. pylori infection does not play any role in its development.

Adolescent↗
PubMed1996

Healing of chronic antral gastritis: effect of sucralfate and colloidal bismuth subcitrate.

BACKGROUND: Colloidal bismuth subcitrate (CBS) causes endoscopic and histological improvement in gastritis and eradication of Helicobacter pylori in patients with non-ulcer dyspepsia (NUD). The effect of sucralfate, a cytoprotective drug, on endoscopic and histologic gastritis and H pylori clearance is not clear. We studied the effect of CBS and sucralfate on these features in patients with NUD. METHODS: Sixty three patients with NUD and H pylori infection were randomized to receive one of the following for four weeks: (i) CBS (240 mg twice daily) (Group 1); (ii) placebo I, similar in size, color and shape to CBS (Group 2); (iii) sucralfate (2.0 g twice daily) (Group 3) and (iv) placebo II, similar to sucralfate (Group 4). Symptoms, endoscopic and histological findings and H pylori status were assessed before and after treatment. RESULTS: Similar symptomatic improvement was observed with each treatment, indicating a placebo effect. Significant endoscopic and histological improvement was observed with CBS only. CBS was better than sucralfate in inducing endoscopic and histological improvement. Clearance rate of H pylori was 46.6% with CBS, 16.6% with its placebo, 33.3% with sucralfate and 13.3% with its placebo. CONCLUSION: CBS is more effective than sucralfate in inducing endoscopic and histologic healing of H pylori-related gastritis among NUD patients.

Adult↗
PubMed1996

Frequency, microbial spectrum and outcome of spontaneous bacterial peritonitis in north India.

AIM: To determine the prevalence, microbial spectrum and outcome of spontaneous bacterial peritonitis (SBP) and its variants in hospitalized cirrhotics. STUDY DESIGN: Prospective cohort study at a tertiary referral center in North India. METHODS: Over a four-month period, 70 consecutive adult patients with decompensated cirrhosis were screened for the presence of SBP or its variants. Ascitic fluid culture was done by direct inoculation of blood culture bottles at the bedside. Blood, urine and other fluids were cultured during hospital stay when clinically indicated. Ascitic fluid total leukocyte count and culture were repeated at any time during hospital stay if the patient showed clinical signs of deterioration. Patients with SBP and culture-negative neutrocytic ascites (CNNA) were treated empirically on the basis of ascitic fluid leukocyte count. RESULTS: Twenty-one of 70 (30%) patients with cirrhosis were diagnosed to have SBP or its variants CNNA and monomicrobial bacterascites (MBA). Ninety-five percent of the patients who developed this complication were in Child-Pugh class C. A causative organism was isolated in 62% of these patients. Gram-negative bucilli accounted for 6 of 10 patients with SBP whereas all cases of MBA were due to infection with Gram-positive cocei. A third of patients with SBP/CNNA had evidence of extra-abdominal focus of infection with the same organism. All episodes of SBP/CNNA were initially treated with either ciprofloxacin (12 patients) or a combination of third generation cephalosporin, cefotaxime and an aminoglycoside, gentamicin (n = 6). Fourteen patients (67%) recovered whereas 6 patients died during hospital stay. CONCLUSION: SBP is a common complication of decompensated liver disease in North India and is associated with significant in-hospital mortality. Ciprofloxacin is an effective drug for initial treatment of SBP/CNNA. Synchronous extra-peritoneal focus of infection is a frequent occurrence in these patients.

Adult↗
PubMed1996

Nosocomial infection due to enterobacter cloacae in a tertiary care hospital in northern India.

A total of 151 Enterobacter cloacae strains isolated from clinical samples (n = 139) and the hospital environment (n = 12) at a tertiary care hospital in northern India during January to October 1993, were analysed. The maximum isolations were during May (n = 24), June (n = 23) and July (n = 22). Urinary tract infection (n = 56) was the most common complication of E. cloacea infection followed by wound infection (42), respiratory tract infection (23) and bacteraemia/septicaemia (18). The frequency of resistance to different drugs was ampicillin 77.4 per cent, cotrimoxazole 79.5 per cent, gentamicin 57.5 per cent, cefotaxime 47 per cent and ofloxacin 36 per cent. Sixty three (41.7%) strains exhibited resistance to multiple drugs. Environmental isolates from bed, hospital diet, hand swab and water from a leaking drain pipe in a ward showed the same resistance pattern. A single index strain could not be identified using phage and biotyping, indicating that a variety of strains were responsible for the nosocomial infection. Adoption of strict aseptic measures and repair of the pipe brought down the infection rate.

Bacterial Typing Techniques↗
PubMed1996

Endoscopic, histologic and microbiologic evaluation of upper abdominal pain with special reference to Helicobacter pylori infection.

OBJECTIVE: To study children with significant upper abdominal pain of unidentifiable etiology and evaluate: (a) the relationship of pain to inflammatory esophago-gastro-duodenal lesions and Helicobacter pylori (HP) infection, and (b) the response to specific therapy. DESIGN: Prospective study. SETTING: Pediatric section of a tertiary referral gastroenterology center. SUBJECTS: Thirty three consecutive children with significant upper abdominal pain [mean age 9.9 +/- 2.7, range 4-15 years; 20 males] were subjected to upper gastrointestinal tract endoscopy and antral mucosal biopsies obtained for rapid urease test (RUT), Gram's staining of impression/crush smears and culture for HP and histologic examination. Patients with HP gastritis were treated with triple therapy, colloidal bismuth subcitrate, amoxycillin and metronidazole, for two weeks. At 8 weeks from the initiation of therapy, patients were re-evaluated for symptoms and HP eradication by repeat endoscopy and antral biopsies. Patients with esophagitis, gastritis and duodenitis without HP infection were treated with ranitidine for 6 weeks. All the patients were followed up for 6 months. RESULTS: Histology revealed antral gastritis in 28/33 (85%) patients. HP infection was present in 12/28 (43%) patients with antral gastritis. Symptomatic improvement with triple therapy was observed in 10/12 (83%) patients with HP gastritis and eradication of HP in 5/7. Improvement on ranitidine therapy was observed in 12/16 (75%) patients with HP negative gastritis. On follow-up, no patient with initial improvement with therapy had relapse of symptoms. CONCLUSION: Symptomatic children with HP related gastritis should be treated with triple therapy and HP negative gastritis with H2-receptor antagonist.

Abdominal Pain↗
PubMed1996

Adherence, invasion and cytotoxin assay of Campylobacter jejuni in HeLa and HEp-2 cells.

Campylobacter jejuni is an important human enteropathogen worldwide. Chickens are the major reservoir and source of campylobacter infection. Ten clinical isolates from human and five chicken strains were tested for the adherence, invasion and cytotoxin assay in HeLa and HEp-2 cells. All human strains adhered to both the HeLa (10(3) to 3 x 10(4) bacteria/mL of cell lysate) and HEp-2 cells (2 x 10(3) to 4 x 10(4) bacteria/mL of lysate). All chicken strains also adhered to the HEp-2 cells (10(2) to 10(3) bacteria/mL), but only two strains adhered to the HeLa cells. Six clinical and none of the chicken strains invaded the mammalian cells. Both the adherence and invasion were better observed in HEp-2 than in HeLa cell lines. All three isolates from patients having invasive diarrhoea and only one strain from a patient having watery diarrhoea produced cytotoxin. All three invasive strains also adhered to polystyrene surface after the localised destruction of the HEp-2 cells, a phenomenon not reported earlier. Adherence was markedly inhibited by the whole cell lysate and the acid glycine extracts, and the results were comparable. This study indicates that the clinical isolates of C. jejuni are more virulent than the chicken strains, HEp-2 is better for the adherence/invasion assay and HeLa is better for cytotoxin assay. The acid glycine extracts probably contain the key adhesins for C. jejuni.

Animals↗
PubMed1995

Antimicrobial susceptibility pattern & biotyping of Helicobacter pylori isolates from patients with peptic ulcer diseases.

Antimicrobial susceptibility of 50 local isolates of Helicobacter pylori from patients with acid peptic diseases was investigated to commonly used antibiotics. The maximum resistance was (66%) detected to metronidazole (MIC > 8 micrograms/ml). The frequency of resistance to ampicillin, erythromycin, ciprofloxacin was in the range of 20-28 per cent; least resistance was observed to tetracycline (10%). The gradient disc diffusion method was found to give reproducible results and also correlated with agar dilution method for minimum inhibitory concentration (MIC). Study of the enzymatic activity of H. pylori isolates showed that all isolates had urease, catalase, oxidase, esterase-lipase, and naphthol-AS-beta-1-phosphohydrolase enzymes and were consistently negative for ten other enzymes tested. Majority of the isolates expressed alkaline phosphatase (17/18), esterase (17/18) and acid phosphatase (14/18). The acid phosphatase had the maximum mean enzymatic activity. There was no difference in enzymatic activity between H. pylori isolates from ulcer and gastritis patients. H. pylori isolates could be typed into five biotypes. Type III was found to be more common (44.4%). This study supports the existence of the strain variations among H. pylori on the basis of the enzyme profiles.

Adolescent↗
PubMed1994

Antimicrobial susceptibility and plasmid analysis of Campylobacter jejuni isolated from diarrhoeal patients and healthy chickens in northern India.

Seventy-five strains of Campylobacter jejuni isolated from humans with diarrhoea (45 strains) and healthy chickens (30 strains) were tested for their susceptibility to different antimicrobial agents: ampicillin, tetracycline, erythromycin, gentamicin, kanamycin, furazolidine and quinolones (nalidixic acid, norfloxacin, ciprofloxacin). The frequencies of resistance to ampicillin and tetracycline were 16 and 9.3% respectively. Two strains (2.7%) exhibited resistance to quinolones as mentioned. One strain (1.3%) was resistant to erythromycin, and both ampicillin plus tetracycline. One strain (1.3%) exhibited resistance to multi-drugs (ampicillin, tetracycline and erythromycin). Resistance to ampicillin was higher in human strain (22.2%) compared to chickens (6.7%). On the contrary, the frequency of resistance to tetracycline was higher in chicken strains (13.3%) than in human (6.7%). All the ampicillin-resistant strains produced beta-lactamase. None of the ampicillin, erythromycin and quinolone-resistant strains contained any plasmid but all the tetracycline-resistant strains contained 23 kilobase (kb) plasmid which could be transferred to an ampicillin-resistant C. jejuni strain. This study thus shows that ampicillin and tetracycline resistance in C. jejuni are common in northern India. Ampicillin resistance is chromosomally determined but tetracycline resistance is mediated through 23 kb plasmid.

Animals↗
PubMed1994

A quantitative microbiological study of bacterial vaginosis.

A quantitative microbial study of vaginal secretions from 100 women with bacterial vaginosis (BV) and 50 healthy women matched for age, was undertaken. This was aimed at comparing the bacterial flora colonising the vagina of sexually active asymptomatic women with those with BV and correlating bacterial counts with presence of symptoms. Of the total 475 bacteria isolated anaerobes were predominant among controls and among patients aerobes and anaerobes had equal prevalences. The increased viable counts of all anaerobes (> 10(7) cfu/g) were related with symptoms. Mobiluncus mulieris could be isolated from one patient and Chlamydia trachomatis antigen was absent in all samples tested. Bacteroides, G. vaginalis and Ureaplasma urealyticum were found to be the most commonly occurring group in women with BV. Lactobacillus, and probably Coryneforms have a protective role in health, preventing disease.

Adolescent↗
PubMed1994

S. typhi with transferable chloramphenicol resistance isolated in Chandigarh during 1983-87.

Plasmid mediated chloramphenicol resistance in S. Typhi has been reported since the outbreak in Kerala in 1972 from India. 876 strains of S. typhi isolated at Chandigarh during Jan 1983 to July 1987 were investigated for the incidence of chloramphenicol resistance. In 1983 34% of the total isolated were resistant to chloramphenicol, in 1984 24%, during 1985 5% & while in 1986 2% of the strains showed chloramphenicol resistance. The resistant strain showed chloramphenicol resistance. The resistant strains had an minimum inhibitory concentration of 64-128 ug/ml for chloramphenicol. All the resistant strains showed multiple drug resistance with the resistance pattern CSSuT. Of these 50 strains were studied for their mechanism of resistance by conjugation experiments which showed that CSSUT pattern could be transferred to E. coli J-53 and E. coli J-62 in primary and secondary transfer experiments indicating that the resistance was carried on a transferable plasmid.

Chloramphenicol Resistance↗