[Biosafety and biosecurity in the medical laboratory. Update and trends]. / Biosiguranta si biosecuritatea în laboratorul medical. Actualitati si tendinte.

Biosafety includes the protective measures against the risks of contamination with pathogen germs in the laboratories that handle pathogens, or stock or manipulate potentially contaminated products, or perform microbiological tests for medical or scientific research purposes, as well as the means of protecting the environment and the human collectivities against hazard contaminations that have as starting point these laboratories. Besides, lately, a new notion emerged, that of biosecurity, which refers to the sum of measures designed to protect workers, environment and population against the loss, theft, use and release in the environment of pathogenic biological agents. The work overviews the present concerns for the regulation of these two notions and the way in which a system for the management of the biological risks in a laboratory that handles pathogens should be documented and implemented. The need for the continuous professional training of the staff and for the establishment of individual and collective responsibilities for preventing biosafety incidents and trespassing biosecurity rules are as well emphasized. The main biosafety measures are pointed out and a series of considerations regarding biosafety and bioterrorism in correlation with the medical laboratory are as well mentioned.

Susceptibility to bacteriophages of Staphylococcus aureus strains received at the National Reference Centre for Staphylococci in Romania 1978-1992.

In order to determine the distribution among lytic groups of Staphylococcus aureus strains circulating in Romania 18,539 strains were phage typed in the National Reference Centre for Staphylococci between 1978 and 1992. Strains susceptible to group II phages prevailed, representing 28.28% of all phage typed strains. The distribution on lytic groups differed in terms of the type of the clinical isolate. The results are statistically analysed and compared with those obtained in Romania by Popovici et al. between 1966 and 1978 as well as with those reported for other geographical areas by other authors.

[Epidemiology studies regarding anthrax epidemic in Romania]. / Studii epidemiologice în epidemia de antrax din România.

Antrax infection, a major bacterial zoonosis caused by B. anthracis, affects animals, particulary the herbivores. The infection can be accidentally transmitted to man, in whom it has two forms. Cutaneous anthrax, more frequently encountered (95%), the transmission being favoured by the contact with contaminated animal or, after the sacrifice of the animal, with various contaminated products (skin, wool, hair, especially of goat, as well as bones, meat, blood); the evolution is favourable following treatment. Internal (visceral)--pulmonary, gastro-intestinal, meningo-encephalytic--anthrax causes quasi-total mortality, despite treatment. Transmission is conditioned by the presence of sporulated forms. The bacteriological diagnosis is based on the detection of the germ on smears or cultures for various pathological specimens (skin lesions, blood, tissues, exudates, c.s.f., sputum, etc), rapid results being obtained by immunofluorescence. The serological diagnosis is indicated by the elevated titer of antibodies, detectable by immunological methods (ELISA). 81 pathological specimens and 16 soil samples suspected of B. anthracis were received by our laboratory in 2000 and were investigated for their morpho-cultural characteristics, under the microscope and using pathogenecity tests. Of the total number of samples investigated, B. anthracis was confirmed in 12 (12.37%) cases.

[Recent proposals for nomenclature and classification of Enterobacteriaceae]. / Propuneri recente privind nomenclatura si clasificarea Enterobacteriaceae-lor.

The authors review recent proposals concerning the taxonomy and nomenclature of Enterobacteriaceae, underlining the differences with respect to the classification in Bergey's Manual of Determinative Bacteriology, 8th edition. The comments are accompanied by tables showing the various more practical tests used for differentiating the taxonomic groups up to species levels.

[Isolation by uroculture of bacterial flora from ambulatory patients]. / Izolarea prin urocultura a florei bacteriene la pacientii investigati ambulatoriu.

In the out patients investigated between 1974 and 1977 a number of 14046 quantitative urocultures were performed; 2206 (15.5%) gave relevant results for a diagnosis of urinary infection. In 98.5% of the cases, infection was caused by Gram negative bacilli, particularly Enterobacteriaceae (98.14%). A set of 11 biochemical tests, performed in a single stage, was used, correctly establishing the genus and in most cases also the species, thus realizing marked economy of material and work. It is considered that the taxonomic listing by this set is sufficient for a diagnosis of urinary infection. In such cases the clinical interest and testing the sensitivity of the strains to antibiotics is of greater importance than determination of the serotype, lysotype or biotype, of prevalent interest in other types of infection produced by enterobacteria, particularly those known to be pathogens.

[Sensitivity of Serratia marcescens to chemotherapy]. / Sensibilitatea la chimioterapice a Ser. marcescens.

The sensitivity of 112 S. marcescens strains, isolated under various clinico-epidemiologic conditions, was tested by the dilution in agar method against 10 different antibiotics and sulfonamides active against Gram-negative bacteria. With the maximum concentrations used only Gentamycin and nalidixic acid were active against a high proportion of the strains tested, i.e. 96.4% and 91.1%. Kanamycin, Neomycin, Chloramphenicol, Streptomycin and Tetracyclin had an inhibitory effect against less than 25% of tested strains. One strain was resistant to all the antibiotics, 49.1% were only sensitive to 2 antibiotics and 33.9% to 3 antibiotics. Among tested strains 22 different antibiotypes were established. Evidence of 2 or more types of resistance within the same epidemic outbreaux, reduces the value of the "antibiotype" as epidemiologic indicator within this species. The readily acquired transfer factors of resistance might be responsible for the marked "mobility" of the antibiotypes, as well as for the spread of S. marcescens in hospital pathology.

An appraisal of a cell culture test for revealing the presence of E. coli thermolabile enterotoxin (L.T.).

Three methods were comparatively used for revealing the presence of thermolabile enterotoxin (L.T.) of E. coli strains causing diarrheal illness of children. From 228 patients 52 L.T.+ strains (22.8%) were identified with the classic rabbit skin test out of which 50 L.T.+ strains (21.9%) also reacted positively in a cell culture test using CHO-KI cells and only 33 L.T.+ strains (14.4%) in the rabbit intestinal loop test. The cell culture test appears to have a constant sensitivity, it is inexpensive, easy to perform and therefore adequate to be carried out in experienced field laboratories.

Salmonella serotype typhimurium phage typing. A critical evaluation.

Of 12,930 Salmonella serotype typhimurium strains, phage typed during 1985-1988, 45.68% were "nontypable" by Anderson's set; the percent of typable strains decreased from 54.17 in 1986 to 30.54 in 1988. Of 90 phage patterns of sensitivity, 22 were currently encountered. Phage types 1, 18 and 104 were most frequent to strain of both human and non-human origin. In food generating S. typhimurium outbreaks, phage types 1 and 36 were prevalent. Except lysotypes 198 and 95, isolated from "single cases" in man only, all other phage types were common in man and animals, too. Introducing other typing methods to serotype typhimurium "nontypable" strains (by Anderson's set) was considered necessary for epidemiological purposes.

[Value of some enzyme tests used in practice for identification of enterobacteria]. / Valoarea unor teste enzimatice folosite în practica de identificare a enterobacteriilor.

A restricted biochemical scheme for the identification of enterobacteria, consisting of 12 enzymatic tests, of which 7 performed on the multitest TSI and MIU media (H2S, the production of acid and gas from glucose, fermentation of lactose/saccharose, mobility, urease and indol production) and 5 additional tests performed separately : lysindecarboxylase, phenylalanindeaminase, beta galactosidase, increase on citrate media and splitting of sodium malonate is proposed. Of 7782 coprocultures, 275 were selected on TSI and MIU media as belonging to one of the groups of known pathogenic enterobacteria ; 94.87% of these cultures were correctly identified by using the 5 additional tests alone. Of the 14 cultures that could not be listed taxonomically, 10 gave atypical reactions with at least one of these tests. The current use of this restricted scheme and the use of the more extensive sets only in doubtful cases presents a real advantage by reducing the volume of work and materials under satisfactorily accurate conditions for identification.

[An episode of hospital infection due to Klebsiella pneumoniae in a neonatal department]. / Episod de infectie spitaliceasca într-un serviciu de nou-nascuti determinat de Klebsiella pneumoniae.

Enterotoxin-producing Klebsiella pneumoniae was implicated in the induction of intrahospital infections in new-born babies. A total of 46 children and 4 adults (hospital personnel) were involved. Most of the subjects (82.6%) had median and light forms of gastroenterocolitis, and recovered following biological re-equilibration. In 17.39% of the cases the evolution was more severe due to advanced dehydration and secondary dissemination of the infection. Two children (approximately 4%) died. Factors that favored the dissemination of the infection were hygiene deficiencies and ignorance of functioning rules of materno-infantile units, and these included: admission to the hospital of working personnel with acute phenomena of enterocolitis; administration of sweetened solutions that were prepared without control and stored at room temperature; the "critical" point represented by the special room for "the accommodation" of the newborns, a "key-point" where infection was disseminated to other wards following dispersion of "adapted babies".

[The incidence of E. coli O157H7 strains in causing hemorrhagic enterocolitis]. / Incidenta tulpinilor de E. coli O157H7 in producerea enterocolitelor hemoragice.

The authors describe the evidencing of the O157H7 E. coli serotype--an enterohaemorrhagic strain of E. coli--for the first time in our country. This germ is incriminated in haemorrhagic enteritis of children and adults, accompanied or not by an uremic haemolytic syndrome. A total of 717 strains were investigated, obtained from cases of haemorrhagic enteritis (283), nonhemorrhagic enteritis (174), food poisoning (27), and a control lot of subjects without signs of enteritis (233). Identification of the strains was done with a screening method (McConkey) with D-sorbitol in place of lactose, and with anti-O157, and anti-H7 sera. The results obtained have indicated a total of 37 positive strains in haemorrhagic enteritis (69.8%), 12 strains in nonhemorrhagic enteritis (22.65%), and 4 strains in food poisoning (7.55%). No strain was isolated from the control group. The percentage of isolated O157H7 E. coli strains in our county is of 7.55% and this contributes to additional knowledge in the definition of the still unknown etiology of diarrhoeic disease in our country.

[Simplified diagnostic scheme for Enterobacteriaceae]. / Schema simplificata de diagnostic al Enterobacteriaceaelor.

After testing 18 experimental variants against 40 reference strains belonging to different Enterovacteriaceae groups, the authors chose a multitest medium that permits concomitant testing of mobility, indol, lysinedecarboxylase and phenylalanine deaminase (MILP). In this medium, the reactions of 3734 strains belonging to the genera Escherichia, Shigella. Salmonella, Citrobacter, Klebsiella, Enterobacter, Serratia. Proteus and Providencia were concordant with the reactions in individual test media, taking as reference, in a proportion of 99.7 and 100%. The authors, associating the MILP medium to TSI agar, propose a simple scheme consisting of eight test which permits, within only 24 hours, the correct identification of the genus and sometimes of the species of cultures or isolated colonies from selective media.

Detection of Serratia outbreaks in hospital.

Infections due to Serratia marcescens were studied in 23 different hospitals. A retrospective study was done in 4 hospitals; all isolates were compared by serological typing, antibiograms, bacteriocin production, and bacteriocin sensitivity. 2 of the hospitals were having cross-infection problems due to antibiotic-resistant strains, but the other 2 had little or no cross-infection. Outbreaks were studied in 19 other hospitals. 9 of these outbreaks were classified as "common source" since contaminated "sterile solutions" were incriminated as the cause in each. One hospital had a "pseudo-outbreak," in which Serratia from E.D.T.A. blood-collecting tubes contaminated blood-cultures as they were collected. All 10 of these strains from common-source outbreaks were generally sensitive to antibiotics. Outbreaks in 9 other hospitals resulted from cross-infection and were caused by strains which were very resistant to antibiotics. Guidelines for detecting outbreaks are given and control measures are suggested.