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Massimo Dozzo,1 Francesca Carobolante,1 Pietro Maria Donisi,2 Annamaria Scattolin,1 Elena Maino,1 Rosaria Sancetta,1 Piera Viero,1 Renato Bassan1 1Complex Operative Unit of Hematology, Ospedale dell’Angelo, 2Simple Departmental Operative Unit of Anatomic Pathology, Ospedale Ss. Giovanni e Paolo, Venice, Italy Abstract: About one-half of all Burkitt lymphoma (BL) patients are younger than 40 years, and one-third belong to the adolescent and young adult (AYA) subset, defined by an age between 15 and 25–40 years, based on selection criteria used in different reports. BL is an aggressive B-cell neoplasm displaying highly characteristic clinico-diagnostic features, the biologic hallmark of which is a translocation involving immunoglobulin and c-MYC genes. It presents as sporadic, endemic, or epidemic disease. Endemicity is pathogenetically linked to an imbalance of the immune system which occurs in African children infected by malaria parasites and Epstein–Barr virus, while the epidemic form strictly follows the pattern of infection by HIV. BL shows propensity to extranodal involvement of abdominal organs, bone marrow, and central nervous system, and can cause severe metabolic and renal impairment. Nevertheless, BL is highly responsive to specifically designed short-intensive, rotational multiagent chemotherapy programs, empowered by the anti-CD20 monoclonal antibody rituximab. When carefully applied with appropriate supportive measures, these modern programs achieve a cure rate of approximately 90% in the average AYA patient, irrespective of clinical stage, which is the best result achievable in any aggressive lymphoid malignancy to date. The challenges ahead concern the following: optimization of management in underdeveloped countries, with reduction of diagnostic and referral-for-care intervals, and the applicability of currently curative regimens; the development of lower intensity but equally effective treatments for frail or immunocompromised patients at risk of death by complications; the identification of very high-risk patients through positron-emission tomography and minimal residual disease assays; and the assessment in these and the few refractory/relapsed ones of new monoclonals (ofatumumab, blinatumomab, inotuzumab ozogamicin) and new molecules targeting c-MYC and key proliferative steps of B-cell malignancies. Keywords: Burkitt lymphoma, adolescents, young adults, treatment, outcome

Sarcoidosis is a systemic granulomatous disease, sometimes characterized by an extrapulmonary localization in 30 - 50% of cases. We describe a 60-year-old Italian man with an unexplained history of fatigue, ascitis and progressive renal function impairment. Diagnosis of hepatic and bone marrow sarcoidosis was established by histology, and fast improvement of renal function was obtained after starting  corticosteroid therapy. Atypical presentation and simultaneous involvement of liver, bone marrow and kidneys make diagnosis of extrapulmonary sarcoidosis still a diagnostic challenge. Delayed diagnosis could lead to serious organ damage like a progressive severe kidney failure.

To determine the effectiveness of two methods to improve the microbial safety of human corneas preserved in organ culture. We compared the number of positive preservation solutions of corneas in organ culture in which the initial short-term hypothermic corneal maintenance solution was supplemented with amphotericin B 2.5 µg/mL and the historical data of microbial test results (2015-2019). In addition, we appraised the efficacy of Gram stain to detect bacterial or fungal contamination in the organ culture solutions of corneas from at-risk donors compared to the culture tests of corneas from not-at-risk donors. Statistical analysis was performed using STATA and statistical significance set at p < 0.05. The number of positive culture tests after preservation was 15 (0.5%) in 2020 compared to a mean of 37 (1.2%) in the period 2015-2019 (p < 0.01), with 10 (1.0%) positive samples in the cohort of 998 corneas from at-risk donors and 5 (0.2%) in the 2046 corneas from not-at-risk donors (p < 0.01). All corneas from at-risk donors tested positive at Gram stain and the results were available 1-3 days before those of the conventional culture tests. Amphotericin B supplementation in the short-term maintenance solution markedly reduced the number of positive microbial tests after organ culture and the early detection of contaminants, including slow-growing microorganisms, by Gram stain before the standard culture results. This meant fewer corneas being discarded and a greater likelihood of preventing post-graft infections., (© 2021. The Author(s).)

Purpose: To compare the effects on adhesive and structural properties of newer preservation conditions to those obtained with an established, standardized protocol (dimethyl sulfoxide at -180 °C). In attempt to simplify and enhance the safety of the procedure, we tested dextran-based freezing medium and a dry condition (no medium) at temperatures of -80 °C., Methods: Five patches of human amniotic membrane were obtained from three different donors. For each donor, five preservation condition were tested: dimethyl sulfoxide at -180 °C, dimethyl sulfoxide at -80 °C, dextran-based medium at -180 °C, dextran-based medium at -80 °C and dry freezing at -80 °C (no medium). At the end of four months storage period, adhesive properties and structure were analyzed., Results: None of the newer preservation protocols showed differences in adhesive and structural properties of the tissues. The stromal layer always kept its adhesiveness, while both structure and basement membrane were not altered by any the preservation protocol., Conclusions: Switching from liquid nitrogen cryopreservation to -80 °C would reduce manipulation, simplify the procedure, making it also cheaper. The use of dextran-based freezing medium or no medium at all (dry condition) would avoid the potential toxicity of the dimethyl sulfoxide-based freezing media., (© 2022. The Author(s), under exclusive licence to Springer Nature B.V.)

Purpose: In the past decades, the human amniotic membrane has been largely applied for several surgical and non-surgical procedures. It has been farther demonstrated that both hAM and cornea share similar patterns of expression of structural components of the basement membrane (like laminin 5 and collagen IV) making hAM an useful tissue for ocular surface reconstruction. Since 1996 in fact, amniotic membrane transplantation has been applied to a large number of ocular surface diseases including Stevens-Johnson syndrome, pterygium, corneal ulceration, ocular surface reconstruction after chemical/thermal burns and in the reconstruction after excision of ocular surface neoplasia. During the previous decades, hAM has achieved a pivotal role in regenerative medicine too.The possibility to preserve human amniotic membrane, without affecting membrane's features, has become pivotal, allowing virological and microbiological analyses to be carried out before grafting. The purpose of the present study is to investigate an easier and cheaper protocol for human amniotic membrane preservation without affecting its properties and structure, ensuring the safety profile of the tissue. We compared the effects on adhesive and structural properties of newer preservation conditions to those obtained with an established, standardized protocol (dimethyl sulfoxide at -160°C). In attempt to simplify and enhance the safety of the procedure, we tested dextran-based freezing medium and a dry condition (no medium) at temperatures of -80°C., Methods: Five patches of human amniotic membrane were obtained from three different donors. For each donor, five preservation condition were tested: dimethyl sulfoxide at -160°C, dimethyl sulfoxide at -80°C, dextran-based medium at -160°C, dextran-based medium at -80°C and dry freezing at -80°C (no medium). At the end of four months storage period, adhesive properties and structure were analyzed., Results: None of the newer preservation protocols showed differences in adhesive and structural properties of the tissues. The stromal layer always kept its adhesiveness, while both structure and basement membrane were not altered by any the preservation protocol., Conclusions: Switching from liquid nitrogen cryopreservation to -80°C would reduce manipulation, simplify the procedure, making it also cheaper. The use of dextran-based freezing medium or no medium at all (dry condition) would avoid the potential toxicity of the dimethyl sulfoxide-based freezing media., (© Author(s) (or their employer(s)) 2022. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Purpose: Despite the increasing use of sentinel lymph node (SLN) mapping after colorectal cancer resection, reported node identification and false-negative rates vary considerably. The main aim of this prospective study was to quantify the false-negative rates on SLN mapping after resection and to evaluate factors influencing them., Methods: Sixty-nine patients with biopsy-proven cancer of the colon and rectum underwent SLN mapping according to a protocol involving the ex vivo submucosal and peritumoral injection of 2-4 ml of Patent Blue V dye. All lymph nodes visualized were marked as SLN and totally embedded, then two 4 microm sections were cut for hematoxylin and eosin staining, and cytokeratin (AE1/AE3) immunostaining. A standard examination of the whole specimen and of the regional non-sentinel lymph nodes was also performed., Results: SLNs were identified in 97.3% of the evaluable cases. A mean of 5.0 SLNs were removed per patient (SD+/-4.2). Nine false negatives were identified. Rectal cancer, tumor size>60mm, number of metastatic non-sentinel lymph nodes, and mucinous tumors were associated with false-negative SLNs. At multivariate analysis, a rectal location and mucinous differentiation were independently associated with false-negative SLNs., Conclusions: Ex vivo SLN mapping after colorectal cancer surgery is technically feasible with a high identification rate. Tumor size and stage, rectal involvement and a mucinous histology seem to interfere with the reliability of SLN staging. It is mandatory to standardize the procedure and selection criteria in order to deal with the question of the reliability of SLN mapping in colorectal cancer., (Copyright (c) 2009 Elsevier Ltd. All rights reserved.)

We analyzed individual VH gene rearrangements in 55 consecutive B-chronic lymphocytic leukemia (B-CLL) patients collected from a northeastern region of Italy, stressing the possible differences related to geographic characteristics of the cohorts studied. Considering the percentage of somatic mutations present in the VH gene sequences and using the 98% cut-off value, 38 of the 55 B-CLL (69%) patients displayed somatic hypermutations and 17 (31%) had a germline configuration. Our results confirm and extend the observations of a bias in the use of certain VH, DH, and JH genes among B-CLL cells. The most frequently used VH genes were VH1-69 (12.7%) with VH3-23 (12.7%) and VH4-34 (10.9%). Collectively these genes accounted for 36.3% of the cases. In the mutated cases, the range of mutations varied from 2% to 15%, with a median of 6.5%. VH1-69 (7 cases, all unmutated) carried few mutations as opposed to VH3-23 (7 cases, 5 of which mutated), VH4-34 (6 cases, all mutated), and VH3-30 (5 cases, all mutated), which show a high load of mutations. D3 family genes were found frequently (38.1%) followed by D2 (27.2%) and D6 (18.1%). The individual D segment most frequently used was D3-3, which was present in 16.3% of cases. There was predominance of the JH4 gene (49%) followed by JH6 (40%). Analysis of the distribution of replacement and silent mutations in the mutated sequences using the method of Lossos showed in 39.4% of cases evidence of antigen selection in the framework region and/or complementary determining regions. In comparison with a recent study on B-CLL patients from the Mediterranean area, the VH4-34 gene was significantly overused in the mutated group at a percentage double that of the Italian cohort reported in this study (10.9% vs. 5%), but at a frequency similar to the entire Mediterranean region (10.7%). We also found an over-representation of VH1-69 usage in the germline group, at a frequency (12.7%) higher than previously described by the same authors (Italian 8%, Mediterranean 10.7%). On the contrary, VH3-07 and VH3-49 were not much used in our study (5.4% and 1.8%, respectively) compared with the Italian group (8% and 5.1%). In our study, VH3-23 gene segment was frequently expressed, at frequency as high as that of VH1-69, a finding in keeping with reported B-CLL Italian data, but higher than the entire series of the Mediterranean area (12.7% vs. 9.2%); VH3-21 gene, frequently expressed in northern European CLL but rarely in the Mediterranean area, was completely absent. This biased usage of VH family genes may reflect a geographic leukemic repertoire, perhaps owing to a peculiar genetic background, depending on variations in germline composition of the IgVH locus or to the effect of a potential environmental element less frequently encountered in different regions.

PCR protocols for immunoglobulin heavy chain (IgH) gene rearrangements amplification make easy the NHL-B identification. In this study we analyzed PCR products by Capillary Electrophoresis (CE) and GeneScan (GS) software, wich offers clear advantages over the conventional methods such as agarose gels (AGGE), characterized by hight rate of false negative and false positive results. We suggested some criteria--not included in previous NHL-B issues--useful to a correct analysis of results in GS. Since 2003, we collected 2,977 samples (2,770 peripheral blood and bone marrow, and 207 tissues) for GS analysis from NHL-B patients. At beginning PCR products were detected by both AGGE and CE. FR2 and FR3 VH regions were amplified by PCR seminested; together with Bcl-6 "housekeeping" gene from the same sample, as marker of DNA quality and PCR efficiency. Bcl-2/IgH and Bcl1/IgH traslocations were also analyzed for follicular and mantle cells lymphomas respectively. Resolution and sensitivity tests, developed with serial diluitions of clonal products in water and in DNA from healthy individuals, showed for GS 1% of resolution limit (3% AGGE) and 0.5% of sensitivity (5% AGGE). Our criteria for correct interpretations of results are: a) use of "house-keeping" gene Bcl-6; b) costant reference scales for hight and molecular weight; c) clonal peak at least twice higher than adiacent peaks; d) position of clonal peak (central or eccentric) as regards to policlonal peaks distributions. e) peaks features for oligoclonal or biallelic rearrangements evaluation. GS is an ideal method for detecting IgH rearrangements and some characteristic traslocations. The precise determination of the size of the PCR product can be used for the minimal residual disease evaluation. Moreover, it allows semi-quantitative resolution of fragments only one base different in size and may be more objective than gel-based methods.

Purpose: The impaired function of corneal epithelial stem cells, located in the limbus, is responsible for corneal surface damage and is clinically characterized by recurrent epithelial defects, conjunctivalization, neovascularization, and corneal opacity. The aim of this study was to investigate corneal limbal stem cell deficiency (LSCD) by means of the impression cytology (IC) technique, using antibodies against cytokeratin 19 (CK19) and cytokeratin 3 (CK3), and to evaluate the diagnostic potential of this approach., Methods: Over a 3-year period (October 1998-June 2001), we collected 113 pairs of IC samples from the eyes of 85 patients with a range of ocular surface diseases and performed an immunocytochemical analysis of CK19 and CK3. Samples with more than 50% cellularity were considered suitable for diagnostic purposes, while samples with less than 50% cellularity were considered with caution. CK19-positive cells in corneal IC were considered an expression of LSCD. We arbitrarily scored LSCD as mild (<25% of CK19-positive cells), moderate (25-50%), and severe (>50%)., Results: One hundred thirteen pairs of IC specimens were obtained from 85 patients; 32 patients (37.6%) had alkaline burns, 18 (21.2%) had other chemical or physical corneal injuries, 13 (15.3%) had complications from wearing contact lenses, 8 (9.4%) had severe microbial keratitis, and 14 (16.5%) had suspicious limbal deficit due to other causes. Nine patients underwent bilateral sampling and 12 had to be resampled. Thirteen pairs of IC specimens were obtained during the follow-up of 8 patients who had undergone limbal stem cell transplantation. In 3 of these patients, IC confirmed reversion to corneal immunophenotype (CK3+/CK19-), whereas in 4, residual limbal damage was still evident; 1 patient relapsed. In the remaining 100 pairs of impressions, we found 77 cases of LSCD, whereas in 16 pairs, we did not find LSCD. Seven pairs were defined as "not valuable" because of the poor quality of both CK samples. Diffuse LSCD, moderate or severe in degree, was found in 26 of 32 patients (81.2%) with alkali burns, whereas mild diffuse LSCD or sectoral LSCD was found in 13 of 18 patients (72.2%) with other chemical-physical injuries, in 10 of 13 patients (76.9%) wearing contact lenses, in 7 of 8 patients (87.5%) with severe microbial keratitis, and in 12 of 14 patients (85.7%) with other corneal pathologies. The quality of impressions was assessed in 77 cases and found to be good or discrete for both CKs in 32 cases (41.5%) and poor in 45 (58.5%): in 46.7% of these cases, the IC was poor only for CK19 and in 45.4% only for CK3., Conclusions: Immunocytochemistry for seeking out CK19- and CK3-positive cells on corneal IC is a simple and practical method to investigate LSCD. We believe that this technique could have an important role in evaluating patients undergoing therapeutic penetrating keratoplasty to select those who would benefit from limbal stem cell transplantation. Since sampling has been shown to be a critical point, we believe that any improvement in this area will also help to improve the methodology and will contribute to its wider utilization.

Background: Helicobacter pylori eradication therapy can be unsuccessful in 5 to 20% of patients., Aim: To investigate the validity of a strategy using triple therapies for the retreatment of patients with eradication failure, avoiding retreatment with antibiotics prone to induce resistance after use in the first treatment., Patients and Methods: From a consecutive sampling of 108 patients still Helicobacter pylori-positive after a first course of antibiotic-based treatment, 74 (68.5%) agreed to a second course of triple therapy. Group 1 (N = 17): treatment failures on an imidazole (1)-based therapy were retreated with clarithromycin (C)-based regimen; Group 2 (N = 28): failures on a C-based therapy with an I-based regimen; Group 3 (N = 7): failures on an IC-based therapy using an I-based regimen and Group 4 (N = 22): failures on a non-I/non-C based therapy with either an I-based, C-based or IC-based regimen. The presence of Helicobacter pylori was assessed by histology and the CLO-test at study entry and two months after stopping therapy., Results: Nine patients were withdrawn from the study (12.2%) due to a lack of end point endoscopy. Helicobacter pylori was cured after the second course of therapy in all but seven patients [10.7% failure by Per Protocol analysis, 21.6% by Intention-To-Treat analysis]. No statistically significant differences were found between the four groups (Group 1: 92.9% PP, 76.5% ITT; Group 2: 90.9% PP, 71.4% ITT; Group 3: PP and ITT 85.7%; Group 4: PP and ITT 86.4%). Minor adverse events were experienced in nine, none of whom required withdrawal from the drug therapy., Conclusions: A second course of triple therapy with alternate antibiotics effectively eradicated Helicobacter pylori, with only very few treatment failures. This suggests that the therapeutic strategy employed may be recommended.

Background: Helicobacter pylori eradication is accomplished using a wide array of drugs combined in a multitude of dosage schedules. The aim of the present study was to define the best 14-day eradication schedule using a PPI plus either two antibiotics or one antibiotic and bismuth., Material and Methods: For this study, 367 subjects (198 males, 169 females, age 22-87 years) with document H. pylori infection of the stomach were recruited from out-patients of the Gastroenterology Department of the Venezia Hospital. In all patients, H. pylori infection was identified by histology and the CLO-test. Patients were treated as follows: 1) PPI (P) plus clarithromycin (C) 250 mg plus amoxicillin (A) 1000 mg bid (P + C + A); 2) P plus C plus bismuth subcitrate (B) 120 mg qid (P + C + B); 3) P plus C plus tinidazole (T) 500 mg bid (P + C + T); and 4) P plus A plus T bid (P + A + T). After two months, an upper gastrointestinal endoscopy was repeated for end point histological evaluation and the CLO- test. Positivity of one of the two methods was considered sufficient to define H. pylori as "not eradicated"., Statistics: Chi-squared test and Fisher exact test., Results: Thirty-three subjects dropped out (six due to adverse events). P + C + B was proven significantly less effective than P + C + A, P + C + T and P + A + T, eradication rates being, respectively, 75.0%, 90.5%, 87.6%, 92.0%, (p = .005, per protocol analysis)., Conclusions: All PPI-based triple therapies tested in this study were effective in curing H. pylori infection; however, P + C + B resulted in rates too low (< 85%) to be recommended. P + C + A and P + A + T resulted in the high cure rates and thus may be considered the treatment of choice.

Objectives: Azithromycin, a new antibiotic chemically related to erythromycin, has been proposed for the cure of Helicobacter pylori, achieving high gastric tissue levels (above the MIC for H. pylori) after oral administration. The aim of the study was to establish whether azithromycin plus metronidazole in association with either omeprazole or bismuth subcitrate is useful in curing H. pylori infection of the stomach., Patients and Methods: The study involved 132 dispeptic patients who proved to be H. pylori infected by antral and corpus histology (Giemsa, modified) and rapid urease test (CLOtest); the Sydney system was used to classify the gastritis. Sixty-three patients received bismuth subcitrate 120 mg q.i.d. for 14 days plus azithromycin 500 mg o.d. for the first 3 days plus metronidazole 250 mg q.i.d. for the first 7 days; 69 patients received omeprazole 40 mg for 14 days plus azithromycin 500 mg o.d. for the first 3 days plus metronidazole 250 mg q.i.d. for the first 7 days. Patients were well matched for common clinical variables. Cure of H. pylori infection was assessed by the same methods 2 months after completion of treatment., Results: Eleven patients dropped out of the study, only one reporting side effects (nausea, vomiting, and epigastric pain). Cumulative "per protocol" cure rate was 66.1% (CI 95%, 58.5-75.3%). There was no statistically significant difference between the two treatment groups: 58.9% (CI 95% 48.4-74.6%) versus 72.3% (CI 95%, 60.7-82.5%). Intention to treat does not substantially modify results. Few side effects were recorded. Cured patients showed a significant reduction in the activity of gastritis., Conclusion: Azithromycin, combined with omeprazole and metronidazole, the cure rate of H. pylori was about 70%. The cure of H. pylori infection improves the activity of gastritis.

Four cases of gastric carcinoma are described that are associated with an osteoclast-like giant cell (OGC) stromal component. The patients were all middle-aged men (range 53-63 years). Microscopically, the tumors were characterized by a bland cytologic appearance, and an either solid or cribriform pattern. Osteoclast-like giant cells were found adjacent to, or intimately intermixed with, the neoplastic cells in the primary gastric masses and in the lymph nodal metastases and were often associated with lymphocytes, histiocytes, and desmoplastic stroma. By immunohistochemistry, mononuclear cells and OGCs showed diffuse positivity for alpha-1-antichymotrypsin, alpha-1-antitrypsin, and CD68. Neoplastic cells that were positive for keratin and CEA, also showed reactivity for vimentin and the latent membrane protein of Epstein-Barr virus in one case. At follow-up, three patients had died at 13, 15, and 24 months after diagnosis, and one is still alive, without evidence of disease, after 120 months. This report describes a novel variant of gastric carcinoma with distinctive and histologic features.

Unlabelled: Helicobacter pylori (Hp) is connected with active/chronic gastritis, gastric gastric and duodenal ulcer. It is not known whether exogenous factors are involved in Hp infection. The aim of this prospective study, performed on 286 consecutive subjects undergoing upper gastrointestinal endoscopy, was to evaluate the influence of smoking and alcohol consumption on Hp infection. For each patient the following parameters were taken into account: sex, age, smoking (no, < 10, > 10 cig/day) and alcohol (no, < 40, > 40 g ethanol/day) intake, antiulcer therapy (no, H2-blockers, omeprazole, sucralfate), presence of gastric or duodenal ulcer (DU). At least two biopsies from both the antrum and the corpus were obtained for histological examination; the gastritis was classified and scored according to the Sydney system., Statistics: chi-squared test (corrected), Fisher's exact test., Results: 43 pts had Hp (27M, 16F; age 57.8 yrs, range 23-91), 47 Hp ++ (25M, 22F; age 61.1, range 19-86), 81 Hp + (48H, 33F; age 56, range 16-84), 115 Hp- (75M, 40F; age 57.8, range 19-84). Hp infection was found to be significantly correlated with presence of ulcer symptoms, gastritis, lymphoid follicles and, among DU patients, with active DU. The other parameters considered did not influence Hp infection. In conclusion smoking habits and alcohol consumption do not affect Hp infection of the stomach.

The erbB2-encoded protein p185 was determined in 130 breast cancer specimens and in 29 non-malignant breast tissues using a recently available ELISA method. The assay showed good characteristics of precision and accuracy. In the non-malignant tissue p185 concentrations were normally distributed and directly correlated with estrogen receptors (ER) and progesterone receptors (PR). In cancer tissue p185 showed higher concentrations than in non-malignant tissue. No relationships were found between p185 and the main clinical and pathological parameters, except that a direct association with nuclear grade was found. We have categorized the breast cancer samples according to p185 concentrations as p185-negative (concentrations lower than the higher non-malignant tissue) and p185-positive. Our data suggested a different behaviour of p185 in samples with low or high p185 concentrations. Indeed, in p185-negative samples the concentrations were directly correlated with both ER and PR. Conversely, p185-positive samples were directly associated with node status and pT, and inversely associated with ER and PR.

Serum levels of prostatic acid phosphatase (PAP) and prostate-specific antigen (PSA) were measured in 78 patients with benign prostate hyperplasia and compared with both the gland weight and the glandular component of prostatic tissue. Both PAP and PSA were significantly higher where prostate was heavier; however, we could not find a consistent factor which could correlate weight increase to marker levels. PSA tended to be higher when glandular component was more expressed. From the present findings we conclude that in patients with prostate cancer, PAP and PSA serum levels should be investigated considering also the benign components of prostate gland.

A retrospective review of 470 consecutive frozen section consultations from two Venetian hospitals (O.C.R. and O.A.M.) was performed in order to assess the accuracy of the procedure. The overall accuracy was 89.4% with a cumulative error rate of 3.6% (false positive + false negative + different diagnosis). Such values are in accord with that reported in literature with the exception of deferred diagnosis whose rate was 7.0% of total diagnosis. It was examined with criticism the latter aspect, focusing on problems and limitations of the method and suggesting a system of quality control by means of periodic review of cases.

Hospital acquired infections (HAI) continue to constitute a major health problem for hospital patients. Such a problem is particularly relevant in Intensive Care Wards. Here infections appear to be directly or indirectly related to the patients' death, and the patients, of course, represent a selected group of the most susceptible hosts in the whole hospital due to their immunosuppressed states, underlying diseases and the numerous and highly invasive diagnostic and therapeutic procedures to which they are submitted. This paper reports the results of a one-year surveillance incidence study carried out in four Intensive Care Wards at Padua Hospital by means of a daily visits to the wards and careful collection of the patients' data in a computerized sheet. Two-hundred-thirty-one of the 859 patients considered developed one or more HAI (HAI percentage 26.9%) for a total of 382 HAIs (Infections ratio 44.5%). Nosocomial pneumonias were the most frequent infections detected, whereas urinary tract infections, bacteremias and wound infections were less common in such patients. The study also confirmed the importance of invasive procedures and surgical operations in the predisposition to HAIs. In particular, the importance of the urinary catheter and of tracheal intubation was outlined. In addition, HAI appeared to be related to the duration of hospitalization and to the severity of the patients' illness. HAIs (especially nosocomial pneumonias) were also closely related to the patients' death. Pseudomonas aeruginosa, S. aureus, Acinetobacter and Streptococcus D were the most frequently isolated agents in the infected patients. Gram-negative agents accounted for 57% of all agents isolated and were particularly frequent in both pneumonias and urinary tract infections.(ABSTRACT TRUNCATED AT 250 WORDS)