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Featured researches published by John Osborn.


Clinical Infectious Diseases | 1998

Reliability of Procalcitonin Concentrations for the Diagnosis of Sepsis in Critically Ill Neonates

Claudio Chiesa; Alessandra Panero; Naila Rossi; Michele Stegagno; Maria De Giusti; John Osborn; Lucia Pacifico

We evaluated the reliability of serum concentrations of procalcitonin for the diagnosis of early- and late-onset sepsis in a neonatal intensive care unit (NICU) setting. Timed procalcitonin determinations were prospectively obtained during two postnatal periods: 0-48 hours of age (period 1) and 3-30 days of age (period 2). In period 1, we measured procalcitonin concentrations in 83 healthy newborns (group 0) and in 120 NICU patients (14 with culture-proven sepsis, group 1A; 14 with clinical septicemia, group 1B; 75 with no evidence of infection, group 2; and 17 with uncertain findings, group 3). After we established 95% hour-specific reference ranges for group 0, we performed multiple linear regression analyses to determine which maternal, intrapartum, and neonatal complications would affect normal procalcitonin values. Maternal diabetes was the only variable identified in group 2 patients that induced a significant deviation from procalcitonin reference ranges. Analyses of the pooled procalcitonin values obtained for group 1 patients over the 48-hour period after birth yielded a sensitivity of 92.6% and a specificity of 97.5% for procalcitonin concentrations in the detection of early-onset sepsis. In period 2, blood samples from 23 cases with systemic infections were analyzed for procalcitonin concentrations at the onset of signs of infection. The control group was formed by matching four uninfected NICU patients to each infected case. None of the procalcitonin values for the 92 controls overlapped those for the cases (sensitivity and specificity, 100%). Procalcitonin is a promising marker for the diagnosis of early- and late-onset sepsis in neonates at high risk for this infection.


Gut | 2006

Gut-associated bacterial microbiota in paediatric patients with inflammatory bowel disease

Maria Pia Conte; Serena Schippa; Ileana Zamboni; M. Penta; F. Chiarini; Lucilla Seganti; John Osborn; Paola Falconieri; O. Borrelli; Salvatore Cucchiara

Background: Clinical and experimental observations in animal models indicate that intestinal commensal bacteria are involved in the initiation and amplification of inflammatory bowel disease (IBD). No paediatric reports are available on intestinal endogenous microflora in IBD. Aims: To investigate and characterise the predominant composition of the mucosa-associated intestinal microflora in colonoscopic biopsy specimens of paediatric patients with newly diagnosed IBD. Methods: Mucosa-associated bacteria were quantified and isolated from biopsy specimens of the ileum, caecum and rectum obtained at colonoscopy in 12 patients with Crohn’s disease, 7 with ulcerative colitis, 6 with indeterminate colitis, 10 with lymphonodular hyperplasia of the distal ileum and in 7 controls. Isolation and characterisation were carried out by conventional culture techniques for aerobic and facultative-anaerobic microorganisms, and molecular analysis (16S rRNA-based amplification and real-time polymerase chain reaction assays) for the detection of anaerobic bacterial groups or species. Results: A higher number of mucosa-associated aerobic and facultative-anaerobic bacteria were found in biopsy specimens of children with IBD than in controls. An overall decrease in some bacterial species or groups belonging to the normal anaerobic intestinal flora was suggested by molecular approaches; in particular, occurrence of Bacteroides vulgatus was low in Crohn’s disease, ulcerative colitis and indeterminate colitis specimens. Conclusion: This is the first paediatric report investigating the intestinal mucosa-associated microflora in patients of the IBD spectrum. These results, although limited by the sample size, allow a better understanding of changes in mucosa-associated bacterial flora in these patients, showing either a predominance of some potentially harmful bacterial groups or a decrease in beneficial bacterial species. These data underline the central role of mucosa-adherent bacteria in IBD.


Blood | 2009

Effects of eradication of Helicobacter pylori infection in patients with immune thrombocytopenic purpura: a systematic review

Roberto Stasi; Ameet Sarpatwari; Jodi B. Segal; John Osborn; Maria Laura Evangelista; Nichola Cooper; Drew Provan; Adrian C. Newland; S. Amadori; James B. Bussel

Whether the eradication of Helicobacter pylori infection can increase the platelet count in patients with immune thrombocytopenic purpura (ITP) is still a controversial issue. To provide evidence-based guidance, we performed a systematic review of the literature published in English, selecting articles reporting 15 or more total patients. We identified 25 studies including 1555 patients, of whom 696 were evaluable for the effects of H pylori eradication on platelet count. The weighted mean complete response (platelet count > or = 100 x 10(9)/L) and overall response (platelet count > or = 30 x 10(9)/L and at least doubling of the basal count) were 42.7% (95% confidence interval [CI], 31.8%-53.9%) and 50.3% (95% CI, 41.6%-59.0%), respectively. In 222 patients with a baseline platelet count less than 30 x 10(9)/L, the complete response rate was 20.1% (95% CI, 13.5%-26.7%) and the overall response rate was 35.2% (95% CI, 28.0%-42.4%). The response rate tended to be higher in countries with a high background prevalence of H pylori infection and in patients with milder degrees of thrombocytopenia. These findings suggest that the detection and eradication of H pylori infection should be considered in the work-up of patients with seemingly typical ITP.


Clinical Chemistry | 2003

C-Reactive Protein, Interleukin-6, and Procalcitonin in the Immediate Postnatal Period: Influence of Illness Severity, Risk Status, Antenatal and Perinatal Complications, and Infection

Claudio Chiesa; Gabriella Pellegrini; Alessandra Panero; John Osborn; Fabrizio Signore; Marcello Assumma; Lucia Pacifico

BACKGROUND Studies of the diagnostic accuracy of most laboratory tests for early-onset neonatal sepsis have yielded variable results. We investigated whether some of this variation might be attributable to differences in population baseline severity and risk status as well as to specific ante- and perinatal variables, independent of the presence of neonatal infection. METHODS The Score for Neonatal Acute Physiology (SNAP) was used to define illness severity, with SNAP Perinatal Extension (SNAP-PE) used to define the combined physiologic and perinatal mortality risk. A total of 134 ill newborns (19 with early-onset infection and 115 with no infection) were available for simultaneous analysis of the association of SNAP, SNAP-PE, and maternal and perinatal variables with C-reactive protein (CRP), interleukin-6 (IL-6), and procalcitonin (PCT) concentrations at birth and at 24 and 48 h of life. RESULTS Early-onset neonatal infection was associated with significant increases in CRP, IL-6, and PCT concentrations at all three time points, independent of illness severity. However, among babies without infection, higher SNAP and SNAP-PE scores were associated with higher IL-6 concentrations at birth. Certain maternal or perinatal variables altered IL-6 and PCT values in the infected as well as in the uninfected neonates. However, if different cutoff points were used at any of the three neonatal ages, PCT sensitivity and specificity were greater than those of CRP or IL-6. CONCLUSIONS Illness severity and risk status are unlikely to interfere with the use of CRP and PCT for detection of early-onset neonatal sepsis. In contrast, the diagnostic value of IL-6 at birth may be altered by physiologic severity and risk indexes. The reliability of CRP, IL-6, and PCT for the diagnosis of early-onset neonatal infection requires specific cutoff values for each evaluation time point over the first 48 h of life.


Intensive Care Medicine | 1999

Application of SOFA score to trauma patients

Massimo Antonelli; Rui Moreno; Jean Louis Vincent; Charles L. Sprung; A. Mendoça; Maurizo Passariello; Luigi Riccioni; John Osborn

Objective: To assess the ability of the SOFA score (Sequential Organ Failure Assessment) to describe the evolution of organ dysfunction/failure in trauma patients over time in intensive care units (ICU). Design: Retrospective analysis of a prospectively collected database. Setting: 40 ICUs in 16 countries. Patients: All trauma patients admitted to the ICU in May 1995. Main outcome measures and results: Incidence of dysfunction/failure of different organs during the first 10 days of stay and the relation between the dysfunction, outcome, and length of stay. Included in the SOFA study were 181 trauma patients (140 males and 41 females).The non-survivors were significantly older than the survivors (51 years ± 20 vs 38 ± 16 years, p < 0.05) and had a higher global SOFA score on admission (8 ± 4 vs 4 ± 3, p < 0.05) and throughout the 10-day stay. On admission, the non-survivors had higher scores for respiratory ( > 3 in 47 % of non-survivors vs 17 % of survivors), cardiovascular ( > 3 in 24 % of non-survivors vs 5.7 % of survivors), and neurological systems ( > 4 in 41 % of non-survivors vs 16 % of survivors); although the trend was maintained over the whole study period, the differences were greater during the first 4–5 days. After the first 4 days, only respiratory dysfunction was significantly related to outcome. A higher SOFA score, admission to the ICU from the same hospital, and the presence of infection on admission were the three major variables associated with a longer length of stay in the ICU (additive regression coefficients: 0.85 days for each SOFA point, 4.4 for admission from the same hospital, 7.26 for infection on admission). Conclusions: The SOFA score can reliably describe organ dysfunction/failure in trauma patients. Regular and repeated scoring may be helpful for identifying categories of patients at major risk of prolonged ICU stay or death.


Pediatric Research | 2008

Nonalcoholic fatty liver disease and carotid atherosclerosis in children

Lucia Pacifico; Vito Cantisani; Paolo Ricci; John Osborn; Elisa Schiavo; Caterina Anania; Eva Ferrara; Giuliano Dvisic; Claudio Chiesa

Nonalcoholic fatty liver disease (NAFLD) is closely associated with several metabolic syndrome features, including obesity, dyslipidemia, insulin resistance, and increased cardiovascular risk. The present study was undertaken to assess whether NAFLD in children is associated with increased carotid artery intima-media thickness (IMT), a marker of early-generalized atherosclerosis. We analyzed carotid IMT along with serum triglycerides, total, low-density lipoprotein and high-density lipoprotein cholesterol, glucose, insulin, insulin resistance index (as homeostasis model assessment of insulin resistance), aminotransferases, leptin, and adiponectin in 29 obese children with NAFLD, 33 obese children without liver involvement, and 30 control children. The diagnosis and severity of NAFLD was based on ultrasound scan, after exclusion of infectious and metabolic disorders. Obese children with NAFLD had significantly increased carotid IMT [mean 0.58 (95% confidence intervals 0.54–0.62 mm)] than obese children without liver involvement [0.49 (0.46–0.52) mm; p = 0.001] and control children [0.40 (0.36–0.43) mm; p < 0.0005]. In a stepwise multiple regression model, after adjusting for age, gender, Tanner stage, and cardiovascular risk factors, the severity of fatty liver was significantly associated with maximum IMT (b = 0.08; p < 0.0005). Our results suggest that NAFLD is strongly associated with carotid atherosclerosis even in childhood.


The Journal of Infectious Diseases | 2002

Human Papillomavirus DNA in Oral Mucosal Lesions

Lucia Giovannelli; Giuseppina Campisi; Anna Lama; Ornella Giambalvo; John Osborn; Valerio Margiotta; Pietro Ammatuna

This study determined the presence of human papillomavirus (HPV) DNA in oral mucosa cells from 121 patients with different types of oral mucosal lesions (13 squamous cell carcinomas, 59 potentially malignant lesions, 49 benign erosive ulcerative lesions) and from 90 control subjects. HPV DNA was detected by nested polymerase chain reaction, and genotype was determined by DNA sequencing. HPV prevalence was 61.5% in carcinomas, 27.1% in potentially malignant lesions, 26.5% in erosive ulcerative lesions, and 5.5% in control subjects. The risk of malignant or potentially malignant lesions was associated with HPV and was statistically significant. HPV-18 was found in 86.5% of HPV-positive lesions but was not associated with a particular type of lesion and was found in 80% of the HPV-positive control subjects. HPV infection was related to older age but not to sex, smoking, or alcohol use; the presence of lesions in the oral cavity increased the risk of HPV infection.


Clinica Chimica Acta | 2011

C reactive protein and procalcitonin: Reference intervals for preterm and term newborns during the early neonatal period

Claudio Chiesa; Fabio Natale; Roberto Pascone; John Osborn; Lucia Pacifico; Enea Bonci; Mario De Curtis

BACKGROUND There is still no study evaluating the influence of gestational age (GA) per se on C reactive protein (CRP) and procalcitonin (PCT) reference intervals. We therefore investigated how length of gestation, age (hours), and prenatal and perinatal variables might influence the levels of CRP and PCT. We also determined 95% age-specific reference intervals for CRP and PCT in healthy preterm and term babies during the early neonatal period. METHODS One blood sample (one observation per neonate) was taken for CRP and PCT from each newborn between birth and the first 4 (for term), or 5 days (for preterm newborns) of life by using a high-sensitive CRP and PCT assays. RESULTS Independently of gender and sampling time, GA had a significantly positive effect on CRP, and a significantly negative effect on PCT. Compared with healthy term babies, healthy preterm babies had a lower and shorter CRP response, and, conversely, an earlier, higher, and longer PCT response. CRP reference intervals were affected by a number of pro-inflammatory risk factors. CONCLUSIONS Age- and GA-specific reference ranges for both CRP and PCT should be taken into account to optimize their use in the diagnosis of early-onset neonatal sepsis.


The American Journal of Gastroenterology | 2004

Effect of proton pump inhibitors and antacid therapy on 13C urea breath tests and stool test for Helicobacter pylori infection.

Luigi Gatta; Nimish Vakil; Chiara Ricci; John Osborn; Andrea Tampieri; Federico Perna; Mario Miglioli; Dino Vaira

OBJECTIVE:There is uncertainty about the best method of testing patients for Helicobacter pylori (H. pylori) infection while they are taking proton pump inhibitors. The aim of this study was to determine: (i) if the decreased sensitivity of the urea breath test during proton pump inhibitor is corrected by different techniques for breath testing and (ii) if the sensitivity of stool test is decreased with the administration of proton pump inhibitors.METHODS:Prospective randomized single-blind study was performed in a tertiary care university hospital. Out of 72 H. pylori infected patients endoscoped for upper abdominal symptoms 48 were randomized to proton pump inhibitors (omeprazole 20 mg each day or esomeprazole 40 mg each day) and 24 to antacid (aluminum hydroxide 800 mg each day) for 14 days. Several breath tests (standard 75 mg 13C-UBT with citric acid, with orange juice, a tablet breath test with 100 and 50 mg of 13C), and a stool test were carried out. Baseline samples were collected before and after treatment.RESULTS:The baseline sensitivity for all breath tests was 100% in both groups; for stool test it was 97.8% (95% CI: 88.7–96.6) and 90% (95% CI: 69.9–97.2) in the proton pump inhibitor and antacid group, respectively. After treatment, the sensitivity of tests was significantly low (UBTs range: 77.1%–85.4%; stool test: 83%; 95% CI: 63.9–91.1), while it was unchanged in the antacid group.CONCLUSIONS:False negative breath and stool tests are equally common in patients taking proton pump inhibitors. Antacids do not impair the sensitivity of the breath tests or the stool test.


PLOS Medicine | 2006

Long-term outcome of otherwise healthy individuals with incidentally discovered borderline, thrombocytopenia

Roberto Stasi; S. Amadori; John Osborn; Adrian C. Newland; Drew Provan

Background The long-term outcome of individuals with mild degrees of thrombocytopenia is unknown. Methods and Findings In a prospective study conducted between August 1992 and December 2002, 260 apparently healthy individuals with incidentally discovered platelet counts between 100 × 109/l and 150 × 109/l were monitored for 6 mo to determine whether their condition persisted. The monitoring period was completed in 217 cases, of whom 191 (88%) maintained stable platelet counts. These 191 individuals were included in a long-term follow-up study to gain knowledge of their natural history. With a median time of observation of 64 mo, the thrombocytopenia resolved spontaneously or persisted with no other disorders becoming apparent in 64% of cases. The most frequent event during the study period was the subsequent development of an autoimmune disease. The 10-y probability of developing idiopathic thrombocytopenic purpura (ITP), as defined by platelet counts persistently below 100 × 109/l, was 6.9% (95% confidence interval [CI]: 4.0%–12.0%). The 10-y probability of developing autoimmune disorders other than ITP was 12.0% (95% CI: 6.9%–20.8%). Most of the cases (85%) of autoimmune disease occurred in women. Conclusions Healthy individuals with a sustained platelet count between 100 × 109/l and 150 × 109/l have a 10-y probability of developing autoimmune disorders of 12%. Further investigation is required to establish whether this risk is higher than in the general population and whether an intensive follow-up results in an improvement of prognosis.

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Claudio Chiesa

National Research Council

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Lucia Pacifico

Sapienza University of Rome

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Angela Spinelli

Istituto Superiore di Sanità

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Caterina Anania

Sapienza University of Rome

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Carola Severi

Sapienza University of Rome

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