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K Fonseca

Publications and source records attributed to K Fonseca.

17 recordsLinked to original sources
PubMed2001

Successful stenting of a complex inferior vena cava stenosis using a modified sharp recanulization technique.

We describe a case of a 30-year-old male who presented with features of noncirrhotic portal hypertension, who was diagnosed to have inferior vena cava (IVC) obstruction. IVC angiogram and ultrasound study revealed a long-segment (36 mm long), chronic total thrombotic occlusion that was dilated and stented with a satisfactory end result. The unique feature of this case is a modified sharp recanulization technique involving the use of Brokenborough (septal puncture) needle and Mullin dilator to create a track in such a long, chronic total occlusion under simultaneous ultrasound and fluoroscopic guidance.

Adult↗
PubMed2001

Characterization of Salmonella associated with pig ear dog treats in Canada.

In the summer of 1999, the incidence of Salmonella enterica serotype Infantis infections in Alberta rose dramatically. Subsequent laboratory and epidemiological investigations established that an outbreak of human disease caused by this organism was occurring across Canada and was associated with pet treats for dogs produced from processed pig ears. Laboratory investigations using phage typing and pulsed-field gel electrophoresis (PFGE) established that isolates of Salmonella serotype Infantis from pig ear pet treats and humans exposed to pig ear pet treats comprised a well-defined subset of all isolates analyzed. Of the 53 subtypes of Salmonella serotype Infantis obtained around the time of the outbreak as defined by PFGE and phage typing, only 6 subtypes were associated with both human infection and isolation from pig ears. Together with information from epidemiological studies, these investigations established pig ear pet treats as the cause of the Salmonella serotype Infantis outbreak. The results are consistent with a model in which contaminated pig ear pet treats constitute a long-term, continuing vehicle for infection of the human population rather than causing temporally delimited point-source outbreaks. During the course of this outbreak, several other Salmonella serotypes were also isolated from pet treats, suggesting these products may be an important source of enteric infection in both humans and dogs. Though isolates of Salmonella serotypes other than Salmonella serotype Infantis from pet treats were also subjected to PFGE and phage typing, no link with human disease could be definitively established, and the contribution of pig ear pet treats to human disease remains unclear. Elimination of bacterial contamination from pet treats is required to reduce the risk of infection from these products.

Alberta↗
PubMed2000

Broken guidewire fragment: a simplified retrieval technique.

We report a technique for retrieval of a broken angioplasty wire fragment from the coronary system using a more simplified technique that does not involve the use of a snare or any other retrieval tool. With the use of an additional angioplasty wire and a balloon catheter, we could safely remove the broken wire fragment from the coronary system and circulation in a very short time.

Angioplasty, Balloon, Coronary↗
PubMed2000

Pig and goat blood as substitutes for sheep blood in blood-supplemented agar media.

In many developing countries sheep and horse blood, the recommended blood supplements in bacteriological media, are not readily available, whereas pig and goat blood are. Therefore, this study examined the use of pig and goat blood as potential substitutes for sheep blood in blood-supplemented bacteriologic media commonly used in clinical microbiology laboratories. In general, the growth characteristics and colony morphologies of a wide range of aerobic and anaerobic bacteria and Candida albicans were similar on media containing pig, goat, and sheep blood, although differences were found. Enterococcus sp. uniformly produced alpha-hemolysis when incubated in CO(2), but in anaerobic conditions the hemolysis varied. In contrast, beta-hemolytic streptococci produced identical hemolytic reactions on all three media. Synergistic hemolysis was not observed on pig blood agar in the CAMP test nor on goat blood agar in the reverse CAMP test. The preparation of chocolate agar (heated) with pig blood required heating to a higher temperature than with sheep or goat blood to yield suitable growth of Haemophilus species. In general, we conclude that pig and goat blood are suitable alternatives to sheep blood for use in bacteriological media in settings where sheep and horse blood are not readily available.

Agar↗
PubMed2000

Fatal hepatic decompensation in a patient with hepatitis B cirrhosis following famciclovir withdrawal.

Hepatitis B virus (HBV) infection is a major cause of chronic liver disease worldwide. Famciclovir is a nucleoside analogue with potent antiviral activity that appears promising in the management of patients with HBV infection. No data exist regarding the safety of nucleoside analogue withdrawal in patients treated for HBV cirrhosis. The authors describe a 41-year-old man with compensated HBV cirrhosis who developed fatal hepatic decompensation due to a rebound in viral replication within six weeks of discontinuing famciclovir therapy. Although several mutations in the HBV DNA polymerase gene have been documented, none has been associated with famciclovir resistance or adverse clinical outcomes. Clinicians should consider the risk of inducing serious flares in hepatic inflammation as a result of abrupt nucleoside analogue withdrawal. Until further data are available regarding the safety of withdrawal of these agents, indefinite treatment may be required in patients with established cirrhosis.

2-Aminopurine↗
PubMed1997

Human immunodeficiency virus seroprevalence and risk behaviors in patients attending sexually transmitted disease clinics in Alberta.

OBJECTIVE: To investigate the dissemination of human immunodeficiency virus (HIV) and hepatitis C infection in association with sexually transmitted diseases (STDs), sexual practices, and injection drug use. All eligible men and women attending two STD clinics in Alberta, Canada, from May 1994 to May 1995 were studied. STUDY DESIGN: Anonymous, unlinked serosurveys were performed using leftover sera drawn for routine syphilis, hepatitis B, or HIV testing. Self-administered questionnaires collected a wide range of data: demographic, sexual behaviors, condom use, STD history, the exchange of drugs or money for sex, and drug and alcohol use. RESULTS: HIV seroprevalence in the overall sample group (n = 6,668) was 1.5%. Univariate analysis showed significant relationships for age between 30 years and 49 years, men having sex with men, injection drug use regardless of sexual orientation, history of STD, anal sex, and exchanging money or drugs for sex. At the multivariate level, only men having sex with men, injection drug use, and age more than 30 years remained predictive of HIV infection. The prevalence of hepatitis C was 3.4% with significant associations being injection drug use and exchanging money or drugs for sex. CONCLUSION: The behavioral associations between sex practices, injection drug use, and HIV and hepatitis C seroprevalence warrant ongoing investigation. Continuing prevention programs targeted at safer sex practices (particularly for men having sex with men) and the use of clean needles are needed.

Adolescent↗
PubMed1997

Molecular detection of an importation of type 3 wild poliovirus into Canada from The Netherlands in 1993.

During the fall and winter of 1992-1993 an outbreak of wild poliovirus type 3-associated poliomyelitis involving 71 patients occurred in The Netherlands. Almost all of the individuals involved in the outbreak belonged to an orthodox religious denomination that prohibits vaccination. A surveillance was initiated to determine if there had been an importation of this same strain of wild poliovirus into a southern Alberta community with a similar religious affiliation. Viral culture of stool samples from consenting individuals in the community resulted in viral isolates which typed as poliovirus type 3. Sequencing of amplicons generated from both the 5' nontranslated region and the VP1/2A portion of the genomes from representative poliovirus isolates indicated a greater than 99% genetic similarity to the strain from The Netherlands. The results of this study show that the utilization of PCR-based diagnostics offers an important molecular tool for the concise and rapid surveillance of possible cases of wild poliovirus importation into communities with individuals at risk for infection.

Adolescent↗
PubMed1995

Detection of Chlamydia trachomatis antigen by enzyme immunoassay: importance of confirmatory testing.

AIM--To determine when a fluorescence assay for Chlamydia trachomatis elementary bodies in the specimen buffer is of most value as a verification test for genital specimens reactive on screening enzyme immunoassay (EIA). METHOD--Genital swabs from high and medium prevalence populations were tested using EIA. Samples with absorbance values greater than the positive threshold and those within the range of 30% below this value were verified by the MicroTrak direct fluorescence assay (DFA) test. Quotients derived from the threshold value and specimen absorbances were used to establish confidence limits for the EIA. RESULTS--Of 13,283 swabs tested, 474 from the high risk group and 236 from the medium risk group were reactive on EIA and confirmed by DFA. Thirty six (5.9%) patients with confirmed reactive samples would have been missed if the kit criteria alone were followed. When confidence limits were applied to the calculated quotients, only those samples with an EIA quotient of > or = 4.0 were universally confirmed by the DFA. CONCLUSION--A scheme of testing which uses the DFA to verify EIA reactive specimens over a specified range was found to improve the sensitivity and specificity of the EIA screening test.

Antigens, Bacterial↗
PubMed1994

Screening for antibody to Chlamydia pneumoniae by the complement fixation test.

We performed a retrospective survey for antibody to Chlamydia pneumoniae, by the microimmunofluorescence (MIF) test, on 120 sera that were previously determined to be positive for antibody to ornithosis antigen by the complement fixation (CF) test. The panel of sera comprised 40 paired acute and convalescent sera, and 40 single samples, from 80 patients. Of these patients, 60% were considered to be serologically positive for C. pneumoniae, based on the antibody titers of IgG, IgM, or both. There was no association between the CF titer to ornithosis antigen and the respective IgG or IgM MIF antibody titers. We propose that, in those laboratories routinely using the CF test, sera found to be positive for ornithosis antigen should be further tested by the MIF in order to clarify, both from an epidemiologic and clinical perspective, whether these patients are also serologically positive for C. pneumoniae.

Adolescent↗
PubMed1992

Antibody to hepatitis C virus in selected groups of a Canadian urban population.

In an anonymous survey, 433 sera from Canadian individuals of selected categories were tested for the presence of antibody to hepatitis C virus (HCV) using a recombinant antigen-based immunoassay. About 50% of intravenous drug abusers (IVDA), 10% of transfusion recipients and an overall average of 7.9% of male homosexuals were reactive for antibody to HCV. Individuals with jaundice and negative hepatitis B virus (HBV) serology were not reactive for antibody to HCV compared with 26.7% of those with positive HBV serology. Similarly 58% of male Federal prisoners with positive HBV serology were also HCV-antibody reactive compared with 15% of those with negative HBV serology. A prevalence of 1.2% was recorded for individuals not in any of the above groups. Of 433 sera, 92 were reactive and the discrimination in absorbance values between reactive and not reactive samples was good except for 13 sera, eight of which gave values considerably higher than the average negative value and five which were just above the positive threshold.

Alberta↗
PubMed1991

Predicting human immunodeficiency virus type 1-positive sera by using two enzyme immunoassay kits in a parallel testing format.

Two algorithms for screening sera for antibody to human immunodeficiency virus type 1 were compared for their efficiency in identifying a true-positive sample in a population with heterogeneous risk factors, using the criteria of specificity and positive predictive value (PPV). In the first algorithm, all sera were screened by using a single enzyme immunoassay (EIA) kit, and a specificity of 98.6% and a PPV of 69.3% was calculated for true-positive sera. The second algorithm employed two different EIA kits in parallel to screen each sample. In the first instance, a specificity and a PPV of 100% was calculated if a positive sample was defined as reactive by both EIA kits; in the second, a specificity of 99.97% and a PPV of 99.4% was obtained if this criterion was extended to include a combination of one reactive and one equivocal result obtained with the two EIA kits.

Algorithms↗
PubMed1986

Inhibition of Pseudomonas aeruginosa from cystic fibrosis by selective media.

Pseudomonas Isolation Agar (selective agent, Irgasan, 25 mg/1) and Pseudomonas Selective Agar (selective agents, cetrimide 200mg/1 and nalidixic acid 15 mg/1) inhibited some strains of P aeruginosa from cystic fibrosis sputum but did not inhibit isolates from other sources. Of 200 cystic fibrosis isolates, 22 were inhibited by 16 mg/1 Irgasan, 45 by 8 mg/1 nalidixic acid, and 15 by 128 mg/1 cetrimide. We recommend that cystic fibrosis sputum should be cultured on selective and non-selective media to maximise the isolation of P aeruginosa.

Carbanilides↗
PubMed1986

Septicaemia and meningitis caused by dysgonic fermenter-2 (DF-2).

A patient developed dysgonic fermenter-2 (DF-2) septicaemia and meningitis after having been bitten by a dog. The pathogenic organism was isolated from the oral cavity of the dog, which, it is believed, is the first time that this has been done. The growth characteristics of the organism and the immunological response of the patient were studied. The isolation of the infecting agent from the dog confirms that the oropharyngeal flora of dogs is a reservoir of the organism: the fastidiousness and slow growth of this Gram negative bacillus may account for the small number of reported cases of infection caused by this organism.

Animals↗
PubMed1983

Pasteurella ureae meningitis and septicaemia.

A 55-year-old male diabetic admitted with deafness, nystagmus, headache and vomiting was found to have meningitis due to Pasteurella ureae and responded to treatment with ampicillin. The P. ureae was unusual in showing X dependency. The family's dogs had had ear infections but no P. ureae were recovered from them when cultured three months later.

Ampicillin↗
PubMed1982

Value of the minimum bactericidal concentration of antibiotics in the management of a case of recurrent Streptococcus bovis septicaemia.

After prostatectomy a 60-year-old man developed Streptococcus bovis septicaemia. The patient did not respond to treatment with a combination of ampicillin and erythromycin and in vitro antagonism between these antibiotics was demonstrated by minimum bactericidal concentration (MBC). The value of determining the MBC of antibiotics used in the treatment of septicaemia is emphasised.

Ampicillin↗
PubMedDate not supplied

HIV prevalence remains low among Calgary's needle exchange program participants.

OBJECTIVES: To determine the demographic characteristics, risk behaviours and prevalence of HIV-1 among injection drug users (IDU) attending Calgary's needle exchange program (NEP). METHODS: A survey was conducted from June through September 1998 among IDU attending Calgary's NEP. Demographic and behaviour characteristics were determined by personal interview and saliva was tested for HIV antibody. RESULTS: There were 278 participants providing 272 saliva specimens. Nine were positive for HIV-1 (3.3%, 95% C.I. 1.6-6.4%). Sexual and injecting practices, cities where drugs had been used, incarceration, addiction treatment and demographic characteristics were described, and a subanalysis for women, youth and Aboriginals was carried out. CONCLUSIONS: HIV prevalence remains low among NEP attenders in Calgary, although high-risk behaviours are common. Women, youth and Aboriginals have unique risk behaviour profiles. Many IDU want to participate in addiction treatment, and strategies should be made to provide accessible, appropriate treatment services.

Adolescent↗