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PubMed1989

Management of perineal necrotizing fasciitis (Fournier's gangrene).

Eleven cases of perineal necrotizing fasciitis were treated in the Department of Surgery, University of Turku, Finland. In 10 cases the diagnosis was made on the basis of the fulminating progression of the infection to scrotal gangrene, identification of multiple underlying pathogenic organisms and toxaemia. In one female patient a corresponding infection developed in the labia majora. Each patient suffered nonspecific symptoms before the gangrene became evident. The management included surgical debridement of the necrotic tissue with incisions and drainage of the involved areas, antibiotic therapy and hyperbaric oxygen (HBO) treatment. The infection originated from the anorectal area in 5 patients, 1 patient had sustained scrotal trauma and in 5 cases the underlying condition was unknown. Colostomy was performed in 6 patients. One patient died 2 days after the admission. All the infections proved to be multimicrobial. Hyperbaric oxygenation was employed as a therapeutic adjunct in the present series, but it should neither replace nor delay surgical intervention. The key points in the management include early diagnosis with prompt surgical debridement and antibiotic therapy. After healthy granulation has appeared, the healing time can be shortened with reconstructive surgical procedures.

Adult↗

PubMed1988

Management and prevention of bacterial diarrhea.

The etiology, pathogenesis, transmission and communicability, diagnosis, and management of infectious diarrhea are reviewed. Infectious diarrhea is common in both industrialized and unindustrialized areas of the world. Better understanding of the etiology and pathogenesis and identification of "new" enteric pathogens has resulted in the use of a variety of drugs to relieve symptoms or to effect a clinical cure. Both host and microbial virulence factors are key in the acquisition of diarrheal illness. Host factors such as extreme age, a dysfunctional gastrointestinal tract, or underlying immunodeficiency enhance the risk of illness after ingestion of a pathogen or its toxins. Microbial virulence factors (the pathogen's ability to invade or produce enterotoxins, neurotoxins, or cytotoxins) characterize the type of illness manifested and the symptom complex (e.g., acute watery diarrhea versus chronic dysentery). Supportive care is indicated in the majority of cases of infectious enteritis, and rehydration is considered the mainstay of therapy in any diarrheal illness accompanied by dehydration. Antimicrobial therapy is beneficial in the treatment of severe diarrhea caused by Shigella, Campylobacter spp., Vibrio cholerae, Escherichia coli, and Clostridium difficile. Infectious diarrhea is common but is often self-limited and of short duration. Therapy frequently consists of symptomatic relief and fluid replacement.

Diarrhea↗

PubMed1987

Diagnosis of bacterial infections of the lung.

This report reviews basic principles behind the choice of specimens in the identification of respiratory bacterial pathogens. It then reviews the major bacterial pathogens and specific specimen sources, covering the strong points, drawbacks, and controversies surrounding the various diagnostic techniques such as sputum Gram stain and culture, transtracheal aspiration, transthoracic needle aspiration, and bronchoscopy.

Bacteria↗

PubMed1985

Microdilution and agar replica identification test systems.

A number of microdilution and agar-replicating systems are currently available for the rapid, accurate identification of common bacterial pathogens. These systems can be highly automated for large clinical laboratories or used manually for small laboratories.

Agar↗

PubMed1979

A ladder curriculum in clinical microbiology.

A continuum of four microbiology courses for medical technology majors has been developed by the Medical Laboratory Science Program at Northeastern University. Using a system approach to curriculum design, the academic and clinical faculty identified career-entry capabilities, delineated appropriate subject content, and developed an instructional system which placed individual topics into one of four courses in the ladder curriculum: a basic, second-year, university-based clinical microbiology course stressing microbial technique and common organism identification; third-year microbiology and cellular physiology courses developing theoretical aspects; a fourth-year, hospital-based clinical microbiology rotation emphasizing isolation and identification techniques for significant pathogens; and a fourth-year, university-based, didactic course covering host defense-organism virulence interactions, infectious disease principles, and new techniques and unusual isolates as reported in the recent journal literature. Based on four years of experience with this system and in light of the publication of the 1978 American Society for Medical Technology (ASMT) Competency Statements, the Northeastern Medical Laboratory Science Program faculty is currently reexamining the continuum to insure completeness and appropriateness of overall subject content, to provide reinforcement, and to remove unnecessary duplication among the courses in the curriculum.

Certification↗

PubMed1983

[New cases of chromoblastomycosis: importances of anatomo-pathologic examinations].

Several cases of chromoblastomycosis have been observed, for 7 years, in the laboratory of Pathology, in the IMTSSA . Their various aspects are described. The diagnosis includes three stages: clinic, mycology and pathology. The most frequent clinical lesions have been observed on the legs. Often, they were like a malignant tumour (carcinoma). The fungal investigation, by direct research of fungi in the lesions, is carried out scarcely, because it is difficult. It should be completed by cultures, in order to isolate the pathogenic agent, but its identification is not possible, if it is not carried out by a laboratory of mycology. The most simple technique , adapted to tropical areas, is the pathological examination. It reveals several points of interest: by analyzing the cutaneous lesions (in order to eliminate a carcinoma)--observing the intensity of the inflammatory reaction--but, first of all, the discovery of the thick-walled dark cells. Two techniques are usual, for staining, but they could be improved by using other special techniques, in order to analyse more carefully the lesions.

Amphotericin B↗

PubMed1984

[Microbiologic principles of antibiotic therapy].

Antibiotic therapy, in contrast to other drug treatments, is aimed at the etiology of a given disease state. The main basis of antimicrobial chemotherapy is thus identification of the causative pathogen and documentation of its susceptibility to the least toxic antibiotic. However, these requirements are frequently impossible to meet in everyday management of infections. In many situations, therefore, decision-making in antimicrobial chemotherapy must be based on a "best-guess" diagnosis regarding the causative pathogen and its susceptibility to the antibiotic. The process of decision-making in antimicrobial chemotherapy for the single most frequent infections encountered in outpatients is discussed, and the pertinent antimicrobial treatment for these infections (pharyngo-tonsillitis, otitis media, sinusitis, bronchitis and urinary tract infections) is outlined.

Adult↗

PubMed1980

[Identification and characteristics of the conjugative R plasmids of conditionally pathogenic E. coli isolated from chronic pyelonephritis patients].

The study on 63 strains of conditionally pathogenic E. coli isolated from patients with chronic pyelonephritis showed that the bacteria of the 47 strains (74.6%) were resistant to one or several antibiotics. 7 strains of such bacteria carried R-plasmids capable of transferring into the cells of E. coli K-12 during conjugation. Most of the identified 9 R-plasmids belonged to the class of the F-like plasmids and were characterized by similar lots of antibiotic resistance markers. DNA of the detected R-plasmids were treated with endonuclease (restrictase) EcoRI. After that the fragments were analysed by means of electrophoresis in agarose gel. On the basis of the restrictogrames it was concluded that the plasmids studied were not identical. A possibility of detecting complexes consisting of different plasmids carrying similar lots of antibiotic resistance markers in the cells of the same strain was shown.

Chemical Phenomena↗

PubMedDate not supplied

Torulopsis glabrata osteomyelitis: report of a case.

This is possibly the first documented case of Torulopsis glabrata osteomyelitis. Torulopis glabrata is a common fungus similar to Cryptococcus. It is though to largely represent a contaminant in routine cultures. The patient was a 58-year-old severely debilitated woman with diabetes. To establish a definitive diagnosis, careful culture and positive identification of the causative pathogen from the fresh bone biopsy were required. Treatment with amphotericin B was successful; however, optimally amphotericin B combined with local surgical excision would be the treatment of choice.

Candida↗

PubMed1995

Empiric monotherapy in neutropenia: a realistic goal?

Infection remains the major cause of morbidity and mortality for cancer patients who become granulocytopenic as a result of chemotherapy. Treatment is instituted at the first sign of infection and before the identification of the causative pathogen (empiric treatment). For many years, standard empiric treatment has been combination therapy with beta-lactams and aminoglycosides. The advent of new broad spectrum antibiotics, such as ceftazidime, has introduced the possibility of empiric monotherapy. However, ceftazidime has only modest activity against infections due to Gram-positive organisms, which presently account for at least 50% of infections in neutropenic patients, and resistance to ceftazidime in Gram-negative organisms has been documented. Meropenem is a new carbapenem with a broad antibacterial spectrum with greater in vitro activity than ceftazidime against staphylococci, streptococci and many Gram-negative bacteria. A comparative study of intravenous meropenem (1 g 8-hourly) and ceftazidime (2 g 8-hourly) in the empiric treatment of febrile neutropenic patients with haematological malignancies has been conducted. In an open, randomised trial of the treatment of 338 febrile episodes, all patients survived to 72 hours on both treatments, and meropenem was found to be at least as clinically effective as ceftazidime in eradicating both Gram-positive and Gram-negative infections. Early modification of treatment (48-72 hours) was required for approximately 40% of patients but occurred less frequently in patients treated with meropenem than with ceftazidime. Tolerability of both treatments was good. Meropenem should be compared with standard combination therapy in a large randomised trial before adopting it as empiric monotherapy for febrile neutropenic patients.

Bacterial Infections↗

PubMed1993

Invasive diagnostic approaches to pulmonary infiltrates.

The clinical and radiographic presentation of pulmonary disease in organ-transplant recipients often fails to allow the specific identification of a causative pathogen or permit the distinction between infectious and noninfectious processes. Frequently, invasive procedures are required to make a specific diagnosis and initiate appropriate therapy. The early use of transtracheal aspiration proved useful for the diagnosis of bacterial and mycobacterial pneumonias. However, its inability to reliably prove pneumonia caused by opportunistic pathogens, such as Pneumocystis carinii and cytomegalovirus, led to very narrow indications for its use among organ-transplant recipients. The introduction of fiberoptic bronchoscopy in the 1970s, with its large variety of related procedures, revolutionized the approach to the diagnosis of pulmonary disease among immunosuppressed patients and today remains the initial procedure of choice in the majority of clinical situations. The diagnostic success and relatively low morbidity of bronchoscopy has narrowed the indications for surgical lung biopsy, despite its excellent diagnostic yield. Open or thoracoscopic lung biopsies are most often used where bronchoscopy has failed to make a diagnosis or where the risk of bleeding prohibits a bronchoscopic biopsy.

Biopsy↗

PubMed1994

Rapid detection and identification of microorganisms from blood cultures.

In an era characterized by increasing emphasis on minimizing laboratory costs, reliable and cost-effective methods for rapidly identifying bacteria and fungi directly from blood cultures have a great deal of appeal to clinical microbiologists. A variety of methods have been evaluated and found to be useful under certain conditions, although none of the methods has been standardized and questions remain as to whether their use improves patient care or reduces hospital costs. Even if these methods do not improve patient care or reduce hospital costs, their use and expense could be justified if they improve laboratory work flow or decrease laboratory costs or both. Several issues remain unresolved, one of which is whether the use of rapid identification methods with a continuous-monitoring blood culture system might allow for a clinically important decrease in the time required to identify blood culture isolates. Another issue is whether subsequent isolation by culture is necessary for microorganisms with predictable antimicrobial susceptibility patterns. These and other issues need to be studied further before the exact clinical usefulness of rapid methods will be known. At this time, no commercial product has been cleared or approved by the Food and Drug Administration (FDA) for the direct detection or identification of both of pathogenic microorganisms from blood culture bottles (Sharon Hansen, PhD, personal communication, 1993). Consequently, laboratory directors should exercise caution in the use of commercial or other products for direct blood culture testing, because manufacturers assume no liability for products that are used for purposes other than that for which they have been approved. In addition, such use of commercial products may be in violation of the rules set forth in the Clinical Laboratory Improvement Act of 1988. Furthermore, as discussed previously, the clinical performance characteristics of many products typically have not been determined, and, therefore, test reference ranges, sensitivity, specificity, and positive and negative predictive values have not been established. Other issues, such as the effect of different blood culture media and additives, also have not been studied adequately, nor are specific controls defined. Therefore, laboratory staff who would like to use commercial products to test blood cultures directly must themselves establish the performance characteristics of the product (keeping in mind the issue of liability) or, preferably, persuade manufacturers to sponsor large-scale controlled clinical trials both to establish performance characteristics and to obtain FDA clearance or approval for such usage of the product.(ABSTRACT TRUNCATED AT 400 WORDS)

Bacteremia↗

PubMed1993

[Bacillary peliosis in AIDS. Anatomo-clinical study of 2 cases].

The authors report two cases of peliosis hepatis, occurring in patients with AIDS, who presented a persistent fever and an hepatomegaly. The liver biopsies showed areas of peliosis, where bacilli were observed by Warthin-Starry stain. In one case, techniques of molecular biology allowed the identification of Rochalimaea henselae, pathogen involved in bacillary angiomatosis. This rickettsia has been newly recognized in the United-States, where 17 cases of bacillary peliosis have been published in immunocompromised hosts and mainly in patients with AIDS. These observations illustrate the clinical and histological features of this new opportunistic infection, as it is described in the literature. The clinical signs include an unexplained fever, an hepatomegaly, and in 75% of the cases, a splenomegaly. The cutaneous lesions of bacillary angiomatosis are associated in 40% of the cases. An antibiotic treatment by erythromycin ensures a complete recovery.

AIDS-Related Opportunistic Infections↗

PubMed1995

Is New Zealand's recent increase in campylobacteriosis due to changes in laboratory procedures? A survey of 69 medical laboratories.

AIMS: To evaluate the contribution of changing procedures in microbiology laboratories over the previous 5 years to the increase in campylobacteriosis notifications. To assess whether regional differences in notification rates are due to variations in laboratory procedures. METHODS: A questionnaire was sent to 69 New Zealand medical laboratories, requesting data on their identification procedures for enteric pathogens, including campylobacter. RESULTS: Changes over the last 5 years in laboratory techniques were insufficient to account for a marked increase in campylobacter isolations. On the basis of data provided by 12 laboratories, the number of specimens that grew campylobacter increased by 49% between 1992 and 1993. Differences in laboratory methods do not explain regional differences in campylobacter notification rates. CONCLUSION: Changes in laboratory methodologies over the last 5 years do not appear to account for the recent national increase in campylobacteriosis notifications.

Campylobacter↗

PubMed1996

Fiberoptic bronchoscopy and bronchoalveolar lavage for the evaluation of pulmonary infiltrates after BMT in children.

Thirty-one fiberoptic bronchoscopies and BAL performed within 4 days after the appearance of pulmonary infiltrates in 28 children who received BMT were reviewed. A causative agent was identified in 67% of patients with diffuse infiltrates (Cytomegalovirus in 8 cases, Pneumocystis carinii in 4) and in 31% of those with localized infiltrates (Aspergillus in 2, bacteria in 2). No relevant side effect was reported. The results obtained from cytological and microbiological testing provided relevant informations for the management of most cases, regardless to the identification of a specific pathogen. We conclude that BAL is a safe diagnostic procedure that should be considered early after the onset of pulmonary complications in BMT recipients.

Adolescent↗

PubMed1997

[Pathways and procedures of mycological diagnosis in veterinary laboratories. A diagnostic approach].

With the increasing fungal affections in humans and animals, the veterinary laboratories will have to reckon with more fungal specimens. A reliable and rapid identification of the etiologic agents will be required. The procedure with mould cultures is described in the general part. In the specific part, the general steps to differenciate medical important moulds (dermatophyes, zygomycetes, dematiaceous fungi, Aspergillus, etc.) are delineated. The identification of some fungal pathogens is possible by the means of the schematic representations.

Animals↗

PubMed1997

Diagnostic value of certain mastitis markers in following up the clinical and bacteriological changes in pharmacotherapeutic studies.

Trends of certain mastitis markers were studied in udder quarters (n = 201) showing clinical symptoms of acute mastitis. Besides the clinical examination, before the first treatment (baseline sample), and about 3 weeks later, 17 to 24 days following the last treatment (control sample) milk samples were collected for bacteriological identification of the mastitis pathogens and for the determination of certain inflammatory markers: somatic cell count (SCC), N-acetyl-beta-D-glucosaminidase (NAGase) and alpha 1-antitrypsin (ATR) activities, as well as bovine serum albumin (BSA) and chloride (Cl-) concentrations. Based upon the clinical and bacteriological status as well as the SCC recorded at the control investigations, 6 groups were established (recovered, latently infected, subclinical mastitis: bacteriologically positive and negative, as well as clinical mastitis: bacteriologically positive and negative). As compared to the baseline samples, all parameters decreased in the case of recovered udder quarters, as well as in those with abated latent infection or subclinical mastitis at the time of control examination. Comparing the control samples of the different categories, characteristic differences were found in NAGase activity, indicating the grade of cytodamaging effect of mastitis. Of the other markers, ATR and Cl- proved to be more adequate for the differentiation than BSA. It can be concluded that, in addition to SCC, first of all NAGase can be recommended for use as an inflammatory parameter in pharmacodynamic studies. Besides these two parameters, ATR and Cl- can also be chosen as a possible third marker.

Acetylglucosaminidase↗

PubMedDate not supplied

Multiplex PCR assay for the detection of mycobacterial DNA sequences directly from sputum.

Time consuming classical diagnostic tests and the increasing incidence of tuberculosis epidemics have rendered the need for new more sensitive diagnostic tools, urgent. This study explored the possibility of a direct and rapid method for the identification and characterization of pathogenic typical and atypical species of mycobacteria from sputum, based on a multiplex PCR assay. Gene bank search on the mycobacterial genome revealed specific sequences that fulfilled the above set criteria. Two pairs of primers were used to amplify a 243 bp fragment of the gene encoding the immunogenic protein MPB 64 and a 133 bp fragment of the gene encoding the 65-KDa mycobacterial antigen. The first pair of primers was selected among others, to detect specifically bacteria of the M. tuberculosis complex, whereas the second, to detect in addition to the latter, those of the M. avium-intracellular complex. Our mutiplex PCR assay, detected and identified correctly, all the mycobacterium tuberculosis and M. avium-intracellulare complex strains provided on pure culture as controls with a sensitivity of 10(-3) colony forming units. Furthermore, by performing our assay on 55 sputum samples from patients with positive culture and Ziehl-Neelsen staining, we identified mycobacterial DNA sequences in all--39 samples with M. tuberculosis complex and 16 with M. avium-intracellulare complex. Out of 300 sputum specimens from patients with clinical evidence of tuberculosis, 149 were positive by our method (95 M. tuberculosis and 54 M. avium-intracellulare complex) whereas 157 samples (95 M. tuberculosis complex, 59 M. avium-intracellulare complex, 1 M. xenopi, and 2 that could not be positively identified) were culture positive and only 95 Ziehl Neelsen positive. These findings suggest that the method described can be applied on sputum, and can identify in one step strains of the M. tuberculosis and M. avium-intracellulare complex and has effectivness comparable to culture methodologies.

DNA Primers↗