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Current standards of sputum examination in respiratory infections with opportunistic bacteria cannot be applied to patients with cystic fibrosis due to their particularities. In 2010, a working group from Great Britain established standards for microbiological processing of samples from patients with cystic fibrosis. Recommendations on sample collection, transportation, storage, and processing, identification of bacterial isolates and in vitro antibiotic susceptibility are made. Also recommended is that the multidisciplinary team monitoring patients with cystic fibrosis to include a microbiologist.

Cystic fibrosis (CF) is a disease that degrades the local defense mechanisms of the lower respiratory tract. As a result, patients develop recurrent infections that progressively deteriorates antiinfection defenses and represent the major cause of mortality. A hallmark of those infections is the diversity of microorganisms isolated from broncho-alveolar lavage or sputum. The clinical significance of isolates is different, the recognition of the role in altering of respiratory function being important in guiding antibiotic therapy. Current data support pathogenicity in CF of S. aureus, P. aeruginosa and B. cepacia complex, the latter two being considered "preterminal bacteria". S. aureus was the most common cause of mortality and morbidity in preantibiotic era. Today, life expectancy was improved with the introduction of antistaphylococcal antibiotics. Hypermutation of P. aeruginosa--the most common species isolated from patients with CF, is the essential factor in the development of multi-resistance to antibiotics. As P. aeruginosa, B. cenocepacia is a virulent species that cause infections with poor prognosis. Microorganisms with secondary role (H. influenzae, S. maltophilia, atypical Mycobacteria, Aspergillus spp) whose clinical significance has not been clarified yet, require further studies.

Acute diarrhea is a major problem with high morbidity and mortality rates in developing countries, especially in children. Complex laboratory investigations are required to define the etiology because of the broad spectrum of etiological agents and the non-specific clinical signs. In the last decade, Cyclospora cayetanensis--a new acid-fast coccidian species--was pointed to be the cause of watery self-limited or prolonged diarrhea in immunocompetent and immunocompromised patients, with very good evolution after treatment with co-trimoxazole. Unlike Cryptosporidium parvum, nonsporulated Cyclospora oocysts are eliminated in feces, with no risk of human to human transmission. Cyclospora cayetanensis is widely spread, producing endemic infections, in Asia and South America and was reported to produce infections in foreign travellers in these areas and epidemic outbreaks of foodborne diarrhea. We describe the first case of acute diarrhea associated with Cyclospora cayetanensis in an immunocompetent child admitted to Iaşi "Sf. Maria" Hospital.

The aim of this study was to find a possible explanation for the resistance pattern of the selected strains and to evaluate the impact in case of isolating such strains. During the period February-March 1998, in the Pediatric Hospital "Sf. Maria" from Iasi, Romania, 12 non-typhoidic Salmonella strains, non-duplicates were isolated from stools of newborns and, in one case, from mother as well. Identification was done by standard methods, and sensitivity testing by disk diffusion method, against the following antimicrobials: Ampicillin (A), Amoxycilin/Clavulanic Acid (AMC), Tetracycline (T), Streptomycin (S), Cloramphenicol (C), Nalidixic Acid (NA), Ciprofloxacin (CIP), Cephalotin (KF), Cefuroxime (CXM), Ceftriaxone (CRO), Cefotaxime (CTX), Ceftazidime (CAZ), Aztreonam (AZT), Imipenem (IPM), Amikacin (AK). All strains showed resistance to: A, AMC, T, S, C, NA, CRO, CAZ, CXM, CTX, KF except one strain, CTX and CRO sensitive. The possible explanation is the production of an extended-spectrum beta-lactamase (ESbLA), detected by microbiological methods (Masuda and clover-leaf). Resistance transfer was realised by using the previously described method. In conjugation experiments we have obtained only one transconjugant, identified as E. coli, that has acquired all resistance determinants. This report highlights on the isolation of multiresistant non-typhoidic Salmonella strains in hospitalised patients without previous antibiotic treatment and possibility of detecting such strains by being aware of the correlation: resistance phenotype-resistance mechanism.

The investigations on the presence of Helicobacter pylori in gastric mucosa biopsy specimens have evidenced another morphologically distinct spiral bacterium, Helicobacter heilmanii, which is associated with histopathological lesions of antral gastritis. The authors found 18 cases of such infection in a number of 1508 children with dyspeptic manifestations examined endoscopically. While H. pylori-associated infection was detected in 48.7% of the cases, H. heilmanii-associated gastritis had a much lower prevalence, 1.1%. The diagnosis was made by microscopic examination of the gram fuchsin-stained smear from a biopsy fragment, the urease test being more commonly erratic or late positive. In 10 cases, the endoscopic examination of gastric mucosa revealed nodularity of antral mucosa, in one of these cases a ulcer lesion at the level of the great curvature being also associated. Histopathological changers of active chronic gastritis have been found but in 4 out of children, the examined fragments of gastric mucosa being collected in most cases from the fundic area: in the child with gastric ulceration the histopathological lesions were of antral acute gastritis. Clinical, bacteriological, endoscopic and histological cure of H. heilmanii gastritis is possible by therapy with bismuth compounds alone.

A. haemolyticum is involved in acute pharingotonsillitis in present, reaching a maximal incidence between 10 and 30 years of age. The authors examined 7402 throats swabs obtained from children between March 1995 and February 1996. The swabs were plated on a selective culture medium: 5% sheep blood agar added with 3.5% NaCl; the plates were incubated for 48 h in aerobic conditions. The colonies of A. haemolyticum have been suspected on the basis of a) the growing time interval (48 h); reduced size (diameter less than 1 mm); c) the presence of a narrow zone of incomplete beta-haemolysis and d) the typical pitting of the culture medium beneath the colony. The definitive identification was realised on the basis of the microscopical appearance (diphtheroid gram-positive bacilli), negative catalase test and inverse CAMP test (narrowing of the haemolytic zone produced by staphylococcal beta-lysine). The frequency of A. haemolyticum in the throat swabs investigated was 0.07% (5 cases), comparing with S. pyogenes which was found in 8.21% of cases.

Isolation and identification of S. anginosus from pathologic products are possible to be realised in informed clinical laboratory, allowing so a better knowledge of these infections' incidences and on adequate treatment. The authors' report 11 cases of pyogenic infection caused by S. anginosus. Five out of these 11 cases evaluated as mixed infections, S. anginosus being associated with anaerobic bacteria. 10 children hospitalised in surgery Department of Children Hospital had infections with different localisations; necrotizing fasciitis, preknee cap abscess, generalised peritonitis, abscess postappendectomy, pleurisy and acute mediastinitis, knee arthritis, acute osteomyelitis of mandible and an infection of the fracture's focus in upper 1/3 of the thigh bone. For all these patients the favoring factor was represented by a traumatic or surgical lesion of the skin or diverse mucosa; oral, oesophageal, intestinal, allowing the access of the normal flora of these covers to normally sterile sites. The eleventh case was an adult with a lung abscess and pleurisy, as a complication of an aspiration pneumonia. The treatment of S. anginosus infections consisted especially in penicillin or ampicillin, associated with metronidazol when anaerobic bacteria were present.

Unlabelled: S. anginosus is a commensal of the oro-pharyngeal mucous membrane without any signification for the local pathology. Ignoring the existence of beta-haemolytic colonies of this species, the risk to report the presence of some beta-haemolytic streptococci that actually belong to the normal flora exists. The antigenic identifications of beta-haemolytic streptococci maintain the confusion either, S. anginosus being able to react with specific sera anti group G, C or A. In our study, two identification criteria out of those available demonstrated a high value: the small or very small colonies' size, especially in secondary cultures and the production of acetoin (Voges-Proskauer test). S. anginosus was isolated with a quite great frequency in pharyngeal exudate from children: 41 strains out of 90 strains of beta-haemolytic non-group A streptococci were S. anginosus. Antigenically they belonged, in numerical order to groups C, G, F or they were ungroupable., In Conclusion: The microbiologist has to identify, but not to report the presence of S. anginosus in pharyngeal exudate, it being a normal component of the oro-pharyngeal flora. Doing so, a better evaluation of the clinical signification of the other beta haemolytic streptococci's non group A will be possible.