Early non-invasive ventilation treatment for severe influenza pneumonia

The role of non-invasive ventilation (NIV) in acute respiratory failure caused by viral pneumonia remains controversial. Our objective was to evaluate the use of NIV in a cohort of (H1N1)v pneumonia. Usefulness and success of NIV were assessed in a prospective, observational registry of patients with influenza A (H1N1) virus pneumonia in 148 Spanish intensive care units (ICUs) in 2009–10. Significant variables for NIV success were included in a multivariate analysis. In all, 685 patients with confirmed influenza A (H1N1)v viral pneumonia were admitted to participating ICUs; 489 were ventilated, 177 with NIV. The NIV was successful in 72 patients (40.7%), the rest required intubation. Low Acute Physiology and Chronic Health Evaluation (APACHE) II, low Sequential Organ Failure Assessment (SOFA) and absence of renal failure were associated with NIV success. Success of NIV was independently associated with fewer than two chest X-ray quadrant opacities (OR 3.5) and no vasopressor requirement (OR 8.1). However, among patients with two or more quadrant opacities, a SOFA score ≤7 presented a higher success rate than those with SOFA score >7 (OR 10.7). Patients in whom NIV was successful required shorter ventilation time, shorter ICU stay and hospital stay than NIV failure. In patients in whom NIV failed, the delay in intubation did not increase mortality (26.5% versus 24.2%). Clinicians used NIV in 25.8% of influenza A (H1N1)v viral pneumonia admitted to ICU, and treatment was effective in 40.6% of them. NIV success was associated with shorter hospital stay and mortality similar to non-ventilated patients. NIV failure was associated with a mortality similar to those who were intubated from the start.     

Risk factors for severe complications of the novel influenza A (H1N1): analysis of patients hospitalized in Italy

Eighty-one patients affected by the novel influenza A (H1N1), hospitalized in North-western Italy, were studied. The median age was 32 years (range 1–81 years). Fifty-six (69%) had an underlying medical condition, including lung disorders (asthma or chronic obstructive pulmonary disease) in 34% and obesity in 25%. Fifty percent of them had pneumonia, 12% were admitted to the intensive care unit and 3% died. Antiviral treatment was initiated in 75% of patients started within 48 h. Older age and lung and neurocognitive disorders were associated with severe disease and death.     

Inflammatory profiles in severe pneumonia associated with the pandemic influenza A/H1N1 virus isolated in Mexico City

The immune mechanisms underlying the pathogenesis of severe pneumonia associated with the A/H1N1 virus are not well known. The objective of this study was to determine whether severe A/H1N1-associated pneumonia can be explained by the emergence of particular T-cell subsets and the cytokines/chemokines they produced, as well as distinct responses to infection. T-cell subset distribution and cytokine/chemokine levels in peripheral blood and bronchoalveolar lavage (BAL) were determined in patients with severe A/H1N1 infection, asymptomatic household contacts, and healthy controls. Cytokine and chemokine production was also evaluated after in vitro infection with seasonal H1N1 and pandemic A/H1N1 strains. We found an increase in the frequency of peripheral Th2 and Tc2 cells in A/H1N1 patients. A trend toward increased Tc1 cells was observed in household contacts. Elevated serum levels of IL-6, CXCL8, and CCL2 were found in patients and a similar cytokine/chemokine profile was observed in BAL, in which CCL5 was also increased. Infection assays revealed that both strains induce the production of several cytokines/chemokines at 24 and 72 h, however, IL-6, CCL3, and CXCL8 were strongly up-regulated in 72-h cultures in presence of the A/H1N1 virus. Several inflammatory mediators are up-regulated in peripheral and lung samples from A/H1N1-infected patients who developed severe pneumonia. In addition, the A/H1N1 strain induces higher levels of pro-inflammatory cytokines and chemokines than the seasonal H1N1 strain. These findings suggest that it is possible to identify biomarkers of severe pneumonia and also suggest the therapeutic use of immunomodulatory drugs in patients with severe pneumonia associated with A/H1N1 infection.     

Subaortic left brachiocephalic vein: computed tomography and magnetic resonance angiography findings

A case of anomalous (subaortic) position of the left brachiocephalic vein was incidentally detected on computed tomography images. Magnetic resonance angiography was performed to demonstrate the relationship of this vessel with other vascular structures. The anomalous vein was formed by the union of the left internal jugular and left subclavian veins. This vein passed downward along the left lateral side of the aortic arch, entered the aorticopulmonary window, descended in the mediastinum between the ascending aorta and the trachea and joined with the right brachiocephalic vein to form the superior vena cava. No cardiac anomalies accompanied the subaortic left brachiocephalic vein in the present case. We present the computed tomography and magnetic resonance angiography findings of this rare anomalous vein.

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Electronic Supplementary Material The french version of this article is available in the form of electronic supplementary material and can be obtained by using the Springer Link server located at .

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Veine brachiocéphalique gauche sous-aortique. Constatations en tomodensitométrie et en angiographie par résonance magnétique

Résumé Un cas de position anormale sous-aortique de la veine brachiocéphalique gauche a été détecté accidentellement au cours d'un scanner. L'angiographie par résonance magnétique a été réalisée pour montrer les rapports de ce vaisseaux avec les autres structures vasculaires. La veine anormale était formée par l'union des veines jugulaire interne et subclavière gauches. La veine se dirigeait vers le bas le long du côté gauche de l'arc de l'aorte, traversait la fenêtre aorto-pulmonaire, descendait dans le médiastin entre l'aorte ascendante et la trachée et rejoignait la veine brachio-céphalique droite pour former la veine cave supérieure. Aucune autre anomalie cardiaque n'accompagnait la veine brachiocéphalique gauche sous-aortique dans le cas présenté. Nous présentons les données tomodensitométriques et d'angiographie par résonance magnétique concernant cette rare veine anormale.

     

Indication for a role of regulatory T cells for the advent of influenza A (H1N1)-related pneumonia

Regulatory T cells (T_regs) have an anti‐inflammatory role. A former study in a limited number of patients found that absolute counts of T_regs increase when infection by the new influenza H1N1 virus is complicated with pneumonia. These results generate the question if H1N1‐related pneumonia is associated with a state of hypo‐inflammation. A total of 135 patients were enrolled with blood sampling within less than 24 h from diagnosis; 23 with flu‐like syndrome; 69 with uncomplicated H1N1‐infection; seven with bacterial pneumonia; and 36 with H1N1‐related pneumonia. T_regs and CD14/HLA‐DR co‐expression were estimated by flow cytometry; concentrations of tumour necrosis factor‐alpha (TNF‐α), of interleukin (IL)‐6 and of soluble triggering receptor expressed on myeloid cells‐1 (sTREM‐1) by an enzyme immunoassay; those of procalcitonin (PCT) by immuno‐time‐resolved amplified cryptate technology assay. Expression of human leucocyte antigen D‐related (HLA‐DR) on monocytes was similar between groups; absolute T_reg counts were greater among patients with H1N1‐related pneumonia than flu‐like syndrome or H1N1‐uncomplicated infection. Serum TNF‐α of patients with bacterial pneumonia was greater than those of other groups, but IL‐10 was similar between groups. Serum PCT was greater among patients with H1N1‐related pneumonia and sTREM‐1 among those with H1N1‐related pneumonia. Regression analysis revealed that the most important factors related with the advent of pneumonia were the existence of underlying illnesses (P = 0·006) and of T_regs equal to or above 16 mm³ (P = 0·013). It is concluded that the advent of H1N1‐related pneumonia is related to an early increase of the absolute T_reg counts. This increase is probably not part of a hypo‐inflammatory state of the host.     

Changes in epidemiology,clinical features and severity of influenza A (H1N1) 2009 pneumonia in the first post-pandemic influenza season

Although the influenza A (H1N1) 2009 virus is expected to circulate as a seasonal virus for some years after the pandemic period, its behaviour cannot be predicted. We analysed a prospective cohort study of hospitalized adults with influenza A (H1N1) 2009 pneumonia at 14 teaching hospitals in Spain to compare the epidemiology, clinical features and outcomes of influenza A (H1N1) 2009 pneumonia between the pandemic period and the first post-pandemic influenza season. A total of 348 patients were included: 234 during the pandemic period and 114 during the first post-pandemic influenza season. Patients during the post-pandemic period were older and more likely to have chronic obstructive pulmonary disease, chronic kidney disease and cancer than the others. Septic shock, altered mental status and respiratory failure on arrival at hospital were significantly more common during the post-pandemic period. Time from illness onset to receipt of antiviral therapy was also longer during this period. Early antiviral therapy was less frequently administered to patients during the post-pandemic period (22.9% versus 10.9%; p 0.009). In addition, length of stay was longer, and need for mechanical ventilation and intensive-care unit admission were significantly higher during the post-pandemic period. In-hospital mortality (5.1% versus 21.2%; p <0.001) was also greater during this period. In conclusion, significant epidemiological changes and an increased severity of influenza A (H1N1) 2009 pneumonia were found in the first post-pandemic influenza season. Physicians should consider influenza A (H1N1) 2009 when selecting microbiological testing and treatment in patients with pneumonia in the upcoming influenza season.     

Antigen-specific H1N1 influenza antibody responses in acute respiratory tract infections and their relation to influenza infection and disease course

BackgroundEarly antibody responses to influenza infection are important in both clearance of virus and fighting the disease. Acute influenza antibody titers directed toward H1-antigens and their relation to infection type and patient outcomes have not been well investigated.ObjectiveUsing hemagglutination inhibition (HI) assays, we aimed to characterize the H1-specific antibody titers in patients with influenza infection or another respiratory infection before and after the H1N1-pandemic influenza outbreak. Among patients with acute influenza infection we related duration of illness, severity of symptoms, and need for hospitalization to antibody titers.MethodsThere were 134 adult patients (average age 34.7) who presented to an urban academic emergency department (ED) from October through March during the 2008–2011 influenza seasons with symptoms of fever and a cough. Nasal aspirates were tested by viral culture, and peripheral blood serum was run in seven H1-subtype HI assays.ResultsAcutely infected influenza patients had markedly lower antibody titers for six of the seven pseudotype viruses. For the average over the seven titers (log units, base 2) their mean was 7.24 (95% CI 6.88, 7.61) compared with 8.60 (95% CI 8.27, 8.92) among patients who had a non-influenza respiratory illness, p < 0.0001. Among patients with seasonal influenza infection, titers of some antibodies correlated with severity of symptoms and with total duration of illness (p < 0.02).ConclusionIn patients with acute respiratory infections, lower concentrations of H1-influenza-specific antibodies were associated with influenza infection. Among influenza-infected patients, higher antibody titers were present in patients with a longer duration of illness and with higher severity-of-symptom scores.     

Evaluation of initial chest computed tomography (CT) findings of COVID-19 pneumonia in 117 deceased patients: a retrospective study

Background/aim There is no study in the literature in which only chest computed tomography (CT) findings of deceased cases obtained at admission were examined, and the relationship between these findings and mortality was evaluated.Materials and methods In this retrospective study, a total of 117 deceased patients with COVID-19 infection confirmed by positive polymerase chain reaction and undergone chest CT were enrolled. We evaluated initial chest CT findings and their relationship, location, prevalence, and the frequency with mortality.Results The mean age of patients was 73 ±18 years; 71 of all patients were male and 46 were female. The predominant feature was pure ground-glass opacity (GGO) lesion (82.0%), and 59.8% of cases had pure consolidation. There was no cavitation or architectural distorsion. Pericardial effusion was found in 9.4% the patients, and pleural effusions were found in 15.3% of them. Mediastinal lymphadenopathy was only 11.9% in total.ConclusionIn deceased patients, on admission CTs, pure consolidation, pleural and pericardial effusion, mediastinal LAP were more common than ordinary cases. It was these findings that should also raise the concern when they were seen on chest CT; therefore, these radiologic features have the potential to represent prognostic imaging markers in patients with COVID-19 pneumonia.     

First influenza season after the 2009 pandemic influenza: characteristics of intensive care unit admissions in adults and children in Vall d'Hebron Hospital

To assess potential differences in epidemiology and management of patients admitted with influenza infection in the intensive care unit (ICU) during the first post-pandemic influenza period. Observational prospective study comparing September 2009–January 2010 with September 2010–January 2011. Variables captured: demographics, co-morbidities, physiological parameters, outcomes and management. Analysis was performed using SPSS v. 13.0; significance was set at p 0.5. Data from 53 patients, 38 adults (age, median 41.5 years; interquartile range (IQR) 32.8–51.3) and 15 children (age, median 2 years, IQR 0.5–9) are presented. Vaccination rates were 0% and 4.3% during the first and second periods, respectively. Differences postpandemic were: 100% of episodes developed after December compared with 16.7% in the 2009 season. Younger children were affected (median age 0.8 years (IQR 0.3–4.8) vs 7 years (IQR 1.25–11.5), p 0.05) and influenza B caused 8.7% of ICU admissions. Influenza A (H1N1) 2009 and respiratory syncytial virus epidemics occurred simultaneously (42.8% of children) and bacterial co-infections doubled (from 10% to 21.7%); the prevalence of co-infections (viral or bacterial) increased from 10% to 39.1% (OR 5.8, 95% CI 1.3–24.8). Respiratory syndromes without chest X-ray opacities reflecting exacerbation of asthma or chronic obstructive pulmonary disease, bronchitis or bronchiolitis increased (from 6.9% to 39.1%, p <0.05) and pneumonia decreased (from 83.3% to 56.5%, p <0.05). Primary viral pneumonia predominated among ICU admissions. Postpandemic ICU influenza developed later, with some cases of influenza B, more frequent bacterial and viral co-infections and more patients with severe acute respiratory infection with normal chest X-ray. Increasing vaccination rates among risk-group individuals is warranted to prevent ICU admission and death.     

Symphysis pubis distance in adults: a retrospective computed tomography study

Background In this retrospective study, symphysis pubis (SP) distance was measured by transverse computed tomography scans. The relation between the SP distance and age, gender, number of birth and body-mass index was studied. Methods Symphysis pubis joint distances were evaluated for the patients who had undergone abdominal or pelvic computed tomography examination for other medical reasons between the dates of March and May 2007. Anterior, middle, and posterior SP joint distances were measured at transverse planes. Normal joint width in women and men was determined. The relation between obtained values, and age, gender, number of birth, as well as body-mass index was studied. Results Symphysis pubis narrows at anterior concurrently with ageing (r = −0.115; P = 0.007). Narrowing, though less, is also observed at posterior (r = −1.50 P = 0.000); however, middle part does not change (r = 0.030; P = 0.489). Number of birth and body-mass index values do not affect SP width. The widths measured at anterior and middle of the SP were significantly higher in women (P = 0.010 and P = 0.002). Conclusions Osteoarthritic changes develop in SP with ageing. However, osteoarthritis in SP, was found to be clinically and radiologically different from that in other symphyseal joints, as SP hardly ever moves, and vertically processing interpubic disc combines pelvis girdle with counterforces, and is supported by very strong ligaments and muscles. Anterior and middle part of the SP joint is wider in women, because fibrocartilaginous disc is too thick to provide the mobility. An erratum to this article can be found at     

Identifying predictors for bacterial and fungal coinfection on chest computed tomography in patients with Pneumocystis pneumonia

BackgroundPneumocystis pneumonia (PCP) is a common opportunistic infection with high mortality in individuals with decreased immunity. Pulmonary coinfections with PCP are associated with poor prognosis. The study aims to identify radiological predictors for pulmonary coinfections in patients with PCP and risk factors for mortality.MethodsThis is a retrospective, five-year study was conducted in a medical center, enrolling patients diagnosed with PCP, who received a chest computed tomography (CT) scan. The radiological findings and medical records of all participants were reviewed carefully by 2 independent doctors. Univariable and multivariable analysis was performed to identify radiological predictors for pulmonary coinfection and clinical risk factors for poor prognosis.ResultsA total of 101 participants were included, of which 39 were HIV-infected and 62 were non-HIV-infected. In multivariable analysis, radiologic predictors on chest CT for coinfection with bacteria pneumonia included lack of ground glass opacity (adjusted odds ratio [aOR], 6.33; 95% confidence interval [CI], 2.03–19.77; p = 0.001) and presence of pleural effusion (aOR, 3.74; 95% CI, 1.27–10.99; p = 0.017). Predictors for fungal pneumonia included diffuse consolidation (adjusted OR, 6.27; 95% CI, 1.72–22.86; p = 0.005) and presence of pleural effusion (adjusted OR, 5.26; 95% CI, 1.44–19.17; p = 0.012). A significantly higher in-hospital mortality was associated with older age, recent corticosteroid exposure, cytomegalovirus coinfection, and acute respiratory failure.ConclusionEarly identification of pulmonary coinfections in PCP using radiological features on the CT scans, will enable appropriate treatment which is crucial to improve the prognosis.     

Influenza in patients with hematological malignancies: Experience at two comprehensive cancer centers

The burden of influenza infections in patients with hematological malignancies (HMs) is not well defined. We describe the clinical presentation and associated outcomes of influenza at two comprehensive cancer centers (center 1 in the United States and center 2 in Mexico). Clinical and laboratory data on patients with HMs and influenza infection diagnosed from April 2009 to May 2014 at the two centers were reviewed retrospectively. A total of 190 patients were included, the majority were male (63%) with a median age of 49 years (range, 1‐88 years), and had active or refractory HMs (76%). Compared to center 1, patients in center 2 were significantly sicker (active cancer, decreased albumin levels, elevated creatinine levels, or hypoxia at influenza diagnosis) and experienced higher lower respiratory tract infection (LRI) rate (42% vs 7%; P < 0.001). In multivariable logistic regression analysis (odds ratio, 95% confidence interval), leukemia, (3.09, 1.23‐7.70), decreased albumin level (3.78, 1.55‐9.20), hypoxia at diagnosis (14.98, 3.30‐67.90), respiratory co‐infection (5.87, 1.65‐20.86), and corticosteroid use (2.71, 1.03‐7.15) were significantly associated with LRI; and elevated creatinine level (3.33, 1.05‐10.56), hypoxia at diagnosis (5.87, 1.12‐30.77), and respiratory co‐infection (6.30, 1.55‐25.67) were significantly associated with 60 day mortality in both centers. HM patients with influenza are at high risk for serious complications such as LRI and death, especially if they are immunosuppressed. Patients with respiratory symptoms should seek prompt medical care during influenza season.     

Cribra orbitalia visualized in computed tomography

Cribra orbitalia are sieve-like lesions of the orbital roof. While common in historic skulls, they have long been absent in those examined in the last decades. Only recently we found low-grade cribra orbitalia in some contemporary cases. Though of unknown origin, this lesion is often attributed to anemia and deficiency diseases. It is theoretically possible to visualize cribra orbitalia in living subjects by computed tomography and thus study their etiology. The aim of our study was to investigate the possibilities of computed tomography for visualizing cribra orbitalia. We used multislice computed tomography (MSCT) in the spiral and sequential mode to image medium-grade cribra orbitalia of moderate severity in a human skull. Virtual endoscopic and 3-D images were produced by post-processing. The best results were obtained by the sequential mode and 3-D reconstruction. Given a thin slice thickness and a wide slice angle between slice plane and the orbital roof, the threshold level seems to be the most important factor influencing realistic reproduction and should be finely adjusted according to bone density. Clinical research may now begin by examining relevant patients undergoing CT.     

Severity assessment tools in ICU patients with 2009 Influenza A (H1N1) pneumonia

The aim of this study was to determine if severity assessment tools (general severity of illness and community-acquired pneumonia specific scores) can be used to guide decisions for patients admitted to the intensive care unit (ICU) due to pandemic influenza A pneumonia. A prospective, observational, multicentre study included 265 patients with a mean age of 42 (±16.1) years and an ICU mortality of 31.7%. On admission to the ICU, the mean pneumonia severity index (PSI) score was 103.2 ± 43.2 points, the CURB-65 score was 1.7 ± 1.1 points and the PIRO-CAP score was 3.2 ± 1.5 points. None of the scores had a good predictive ability: area under the ROC for PSI, 0.72 (95% CI, 0.65-0.78); CURB-65, 0.67 (95% CI, 0.59-0.74); and PIRO-CAP, 0.64 (95% CI, 0.56-0.71). The PSI score (OR, 1.022 (1.009-1.034), p 0.001) was independently associated with ICU mortality; however, none of the three scores, when used at ICU admission, were able to reliably detect a low-risk group of patients. Low risk for mortality was identified in 27.5% of patients using PIRO-CAP, but above 40% when using PSI (I–III) or CURB65 (<2). Observed mortality was 13.7%, 13.5% and 19.4%, respectively. Pneumonia-specific scores undervalued severity and should not be used as instruments to guide decisions in the ICU.     

Rotation of the cervical spinal column: a computed tomography in vivo study

Summary The functional anatomy of the spinal column has mainly been studied in the cadaver. The aim of our study was to determine in vivo the normal axial rotation of the cervical column using computed tomography (CT). Sixty subjects, divided into decades from 20 to 80 years of age were studied. The CT protocol comprised an axial cut at the level of the skull base (C0) and at each vertebral level in the neck, in the neutral position (with the nasal septum vertical) and during rotation of the head. To reduce the exposure to irradiation the subjects were divided into two groups: 40 were studied from C0 to the fifth cervical vertebra (C5) with unilateral rotation at C0 of 10°, 20° and 40° (20 rotations to the left and 20 to the right), and 20 subjects were studied from C0 to the first thoracic vertebra (T1) with a maximum rotation at C0 to left and right. The angular position of a vertebra was defined as the anteroposterior axis with reference in the neutral position to the axis of C0, and in rotation was related to its original axis. At each vertebral level the mean angle of rotation and its standard deviation were calculated (n=30) for the successive intermediate and maximum rotations at C0 level. The rotation of the cervical spine took place mainly at two levels: 58% between C1 and C2 and 24% between C3 and C6. The pairs of vertebrae C0/C1 and C2/C3 provided functional couples where the rotation was minimal. Rotation of the lower cervical spine occurred very early. The percentage of rotation with respect to C0 of each cervical vertebra was constant during the successive rotations. The neutral positions of the vertebrae below the atlas were variable. The findings on rotation to left and to right were comparable. This study determined in vivo the distribution of rotation at each vertebral level of the cervical spine during partial and maximum rotation of the skull base. It facilitates the application of CT to the examination of disorders affecting the rotation of the cervical spinal column.

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Anatomie in vivo de la rotation de la colonne cervicale: étude tomodensitométrique

Résumé L'anatomie fonctionnelle de la colonne cervicale a principalement été établie in vitro sur cadavre. Notre étude avait pour but de déterminer in vivo, par utilisation de la tomodensitométrie (TDM), les normes fonctionnelles de la rotation axiale de la colonne cervicale. 60 témoins répartis en décades de 20 à 60 ans et au delà ont été explorés. Le protocole TDM comportait une coupe axiale sur la base du crâne (C0) et sur chaque étage vertébral cervical, en position neutre (septum nasal vertical) et au cours de rotations de la tête. Afin d'obtenir une irradiation faible les sujets étaient répartis en deux groupes : 40 sujets étaient explorés de C0 à C5 pour une rotation unilatérale de C0 à 10°, 20° et 40° (20 rotations droites et gauches), 20 sujets étaient explorés de C0 à T1 pour une rotation maximale de C0 à droite et à gauche. La position angulaire d'une vertèbre était définie par son axe antéro-postérieur rapporté, en position neutre à l'axe de C0, et en rotation à son axe initial. A chaque étage vertébral, l'angle moyen de rotation, et sa déviation standard, étaient calculés (n>30) pour les rotations séquentielles et maximales de C0. La rotation de la colonne cervicale s'effectuait principalement à 2 niveaux; 58 % entre C1 et C2 et 24 % entre C3 et C6. Les doublets vertébraux C0/C1 et C2/C3 formaient des couples fonctionnels. La rotation de la colonne cervicale inférieure était très précoce. Le pourcentage de rotation, par rapport à C0, de chaque vertèbre cervicale était constant au cours des rotations séquentielles. La position neutre des vertèbres sous-atloïdiennes était variable. Les résultats en rotations droite et gauche étaient comparables. Cette étude détermine in vivo la répartition de la rotation axiale de la colonne cervicale à chaque segment vertébral pour des rotations séquentielles et maximales de la base du crâne. Elle permet l'application de cette technique TDM à l'exploration de la pathologie de la rotation de la colonne cervicale.

     

Phylogenetic analysis of swine influenza viruses recently isolated in Korea

Several influenza A viral subtypes were isolated from pigs during a severe outbreak of respiratory disease in Korea during 2005 and 2006. They included a classical swine H1N1 subtype, two swine-human-avian triple-recombinant H1N2 subtypes, and a swine-human-avian triple-recombinant H3N2 subtype. In the current study, genetic characterization to determine the probable origin of these recent isolates was carried out for the first time. Phylogenetic analysis indicated that all the recent Korean isolates of H1N1, H1N2, and H3N2 influenza are closely related to viruses from the United States. Serologic and genetic analysis indicated that the Korean H1N2 viral subtypes were introduced directly from the United States, and did not arise from recombination between Korean H1N1 and H3N2. We suggest that the H1N1, H1N2, and H3N2 viral subtypes that were isolated from the Korean swine population originated in North America, and that these viruses are currently circulating in the Korean swine population.     

Epiphysial ossification centres in iliosacral joints: anatomy and computed tomography

Summary Bilateral apparently bony structures of different forms and sizes located in the inferior and superior ventral parts of the sacroiliac joints were observed on axial CT images of the pelvic region of juvenile patients. No other pathological changes were noted in the sacroiliac joints of these individuals. In one patient the bony structures could also be seen on a conventional plain radiograph. We also examined 3 juvenile autopsy specimens of this joint using radiology, CT, macroscopical evaluation and histology. In two of them, structures could be detected on the CT scans which were similar to those observed in the young patients. Macroscopic investigations revealed the structures to be secondary ossification centres located in the articular cartilage of the lateral part of the os sacrum at the levels of the first and third sacral segments. According to older anatomical literature, these epiphysial ossification centres contribute to the auricular surface of the lateral part of the os sacrum and the free lateral surface of the inferior sacral parts. They can be observed between the ages of 12 and 25 years and begin to synostose with the lateral part around the age of 18 years. In macerated juvenile specimens of the bony pelvis, free ossicles were not detectable in the region of the sacroiliac joints. Histological peculiarities of the ossification process observed are discussed. These physiologically occurring ossification centres are to be differentiated from pathological alterations appearing as bony or bone-like structures on CT scans.

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Points d'ossification épiphysaire des articulations sacro-iliaques : étude anatomique et tomodensitométrique

Résumé Des formations osseuses apparemment bilatérales, de formes et tailles différentes, localisées dans les parties antéro-supérieures et inférieures des articulations sacroiliaques, ont été observées sur les images de coupes axiales de la région pelvienne chez des patients jeunes. Aucune autre modification pathologique n'a été notée au niveau des articulations sacro-iliaques de ces individus. Chez l'un des patients, les structures osseuses pouvaient aussi être observées sur les radiographies standard. Nous avons aussi étudié cette articulation chez 3 sujets anatomiques juvéniles, par la radiographie, la TDM, l'étude macroscopique et histologique. Chez deux d'entre eux des formations osseuses semblables à celles observées chez les patients jeunes pouvaient être détectées sur les coupes TDM. Les recherches macroscopiques ont montré que ces structures étaient des points d'ossification secondaires localisés dans le cartilage articulaire de la partie latérale du sacrum en regard du 1er et du 3e segments sacrés. Si l'on se réfère à une littérature anatomique plus ancienne, ces points d'ossification épiphysaires contribuent à la surface auriculaire de la partie latérale du sacrum et à la surface libre latérale des parties caudales du sacrum. Ils peuvent être observés entre 12 et 25 ans et commencent à fusionner avec les parties latérales aux environs de la 18e année. Sur les bassins osseux provenant de pièces juvéniles conservées, les ossicules libres n'ont pas pu être décelés dans la région des articulations sacroiliaques. Les particularités histologiques du processus d'ossification observé sont discutés. Ces points d'ossification physiologiques doivent être distingués des altérations pathologiques apparaissant au scanner comme des structures osseuses ou assimilées.