Ultrasound is a widely used technique in the diagnosis of acute appendicitis; nevertheless, its utilization still remains controversial.
The accuracy of the Ultrasound technique in the diagnosis of acute appendicitis in the adult patient, as shown in the literature, was searched for.
The gold standard for the diagnosis of appendicitis still remains pathologic confirmation after appendectomy. In the published literature, graded-compression Ultrasound has shown an extremely variable diagnostic accuracy in the diagnosis of acute appendicitis (sensitivity range from 44% to 100%; specificity range from 47% to 99% ). This is due to many reasons, including lack of operator skill, increased bowel gas content, obesity, anatomic variants, and limitations to explore patients with previuos laparotomies.
Graded-compression Ultrasound still remains our first-line method in patients referred with clinically suspected acute appendicitis: nevertheless, due to variable diagnostic accuracy, individual skill is requested not only to perform a successful exam, but also in order to triage those equivocal cases that, subsequently, will have to undergo assessment by means of Computed Tomography.
Acute appendicitis; Ultrasound; Abdomen (US); Abdominal Pain
In the assessment of polytrauma patient, an accurate diagnostic study protocol with high sensitivity and specificity is necessary. Computed Tomography (CT) is the standard reference in the emergency for evaluating the patients with abdominal trauma. Ultrasonography (US) has a high sensitivity in detecting free fluid in the peritoneum, but it does not show as much sensitivity for traumatic parenchymal lesions. The use of Contrast-Enhanced Ultrasound (CEUS) improves the accuracy of the method in the diagnosis and assessment of the extent of parenchymal lesions. Although the CEUS is not feasible as a method of first level in the diagnosis and management of the polytrauma patient, it can be used in the follow-up of traumatic injuries of abdominal parenchymal organs (liver, spleen and kidneys), especially in young people or children.
Ultrasonography (US); Ultrasound contrast agent (USCA); Contrast-enhanced Ultrasound (CEUS); Computed Tomography (CT); Blunt abdominal trauma
Molecular targeted therapy has shown promise as a treatment for advanced hepatocellular carcinoma (HCC). Sorafenib, a multikinase inhibitor, recently received FDA approval for the treatment of advanced HCC. However, although sorafenib is well tolerated, concern for its safety has been expressed. Celecoxib (Celebrex®) is a selective cyclooxygenase-2 (COX-2) inhibitor which exhibits antitumor effects in human HCC cells. The present study examined the interaction between celecoxib and sorafenib in two human liver tumor cell lines HepG2 and Huh7. Our data showed that each inhibitor alone reduced cell growth and the combination of celecoxib with sorafenib synergistically inhibited cell growth and increased apoptosis. To better understand the molecular mechanisms underlying the synergistic antitumor activity of the combination, we investigated the expression profile of the combination-treated liver cancer cell lines using microarray analysis. Combination treatment significantly altered expression levels of 1,986 and 2,483 transcripts in HepG2 and Huh7 cells, respectively. Genes functionally involved in cell death, signal transduction and regulation of transcription were predominantly up-regulated, while genes implicated in metabolism, cell-cycle control and DNA replication and repair were mainly down-regulated upon treatment. However, combination-treated HCC cell lines displayed specificity in the expression and activity of crucial factors involved in hepatocarcinogenesis. The altered expression of some of these genes was confirmed by semi-quantitative and quantitative RT-PCR and by Western blotting. Many novel genes emerged from our transcriptomic analyses, and further functional analyses may determine whether these genes can serve as potential molecular targets for more effective anti-HCC strategies.
[5,11,17,23-Tetra-tert-butyl-25,27-(3,6-dioxaoctan-1,8-dioxy)-26,28-bis(pyridin-2-ylmethoxy)calixarene]sodium iodide–1,2,4,5-tetrafluoro-3,6-diiodobenzene–methanol (2/3/4)
The title compound, [Na(C62H76N2O6)]I·1.5C6F4I2·2CH3OH, is composed of five components: a calixarene derivative (hereinafter C4), a sodium cation, an iodide anion, a 1,2,4,5-tetrafluoro-3,6-diiodobenzene (tFdIB) molecule and a methanol molecule in a 1:1:1:1.5:2 ratio. The complex shows several interesting features: (i) the polyoxygenated loop of C4 effectively chelates a sodium cation in the form of a distorted octahedron and separates it from the iodide counter-ion, the shortest Na+⋯I− distance being greater than 6.5 Å; (ii) the cavity of C4 is filled by a methanol molecule; (iii) a second methanol molecule is hydrogen-bonded to the N atom of a pyridinyl substituent pendant of C4 and halogen-bonded to the I atom of a tFdIB molecule; (iv) the two I atoms of another tFdIB molecule are halogen-bonded to two iodide anions, which act as monodentate halogen-bond acceptorss; (v) one of the two tFdIB molecules is located about a centre of inversion.
Social support has a strong impact on individuals, not least on older individuals with health problems. A lack of support network and poor family or social relations may be crucial in later life, and represent risk factors for elder abuse. This study focused on the associations between social support, demographics/socio-economics, health variables and elder mistreatment.
The cross-sectional data was collected by means of interviews or interviews/self-response during January-July 2009, among a sample of 4,467 not demented individuals aged 60–84 years living in seven European countries (Germany, Greece, Italy, Lithuania, Portugal, Spain, and Sweden).
Multivariate analyses showed that women and persons living in large households and with a spouse/partner or other persons were more likely to experience high levels of social support. Moreover, frequent use of health care services and low scores on depression or discomfort due to physical complaints were indicators of high social support. Low levels of social support were related to older age and abuse, particularly psychological abuse.
High levels of social support may represent a protective factor in reducing both the vulnerability of older people and risk of elder mistreatment. On the basis of these results, policy makers, clinicians and researchers could act by developing intervention programmes that facilitate friendships and social activities in old age.
Over the past few years, significant advances have occurred in both our understanding of the complexity of signal transduction pathways as well as the isolation of specific inhibitors which target key components in those pathways. Furthermore critical information is being accrued regarding how genetic mutations can affect the sensitivity of various types of patients to targeted therapy. Finally, genetic mechanisms responsible for the development of resistance after targeted therapy are being discovered which may allow the creation of alternative therapies to overcome resistance. This review will discuss some of the highlights over the past few years on the roles of key signaling pathways in various diseases, the targeting of signal transduction pathways and the genetic mechanisms governing sensitivity and resistance to targeted therapies.
Targeted Therapy; Therapy Resistance; Cancer Stem Cells; Raf; Akt; PI3K; mTOR; AMPK; Metformin
The use of medicines by elderly people is a growing area of concern in social pharmacy. A significant proportion of older people do not follow the recommendations from physicians and refrain from buying prescribed medications. The aim of this study is to evaluate associations between self-rated health, somatic complaints and refraining from buying prescribed medications by elderly people.
Data was collected in a cross-sectional study in 2009. We received 624 completed questionnaires (response rate – 48.9%) from persons aged 60–84 years living in Kaunas (Lithuania). Somatic complaints were measured with the 24 item version of the Giessen Complaint List (GBB-24). Logistic regression (Enter model) was used for evaluation of the associations between refraining from buying medications and somatic complaints. These associations were measured using odds ratio (OR) and calculating the 95% confidence interval (CI).
The mean scores in total for the GBB scale and sub-scales (exhaustion, gastrointestinal and cardiovascular) were lowest among respondents who did not refrain from buying prescribed medications (means for GBB-24 scale: 21.04 vs. 24.82; p=0.001). Logistic regression suggests that somatic complaints were associated with a increased risk of refraining from buying prescribed medications (OR=1.35, 95% CI=1.15-1.60).
Somatic complaints were significantly associated with the decision to refrain from buying prescribed medications.
Use of medication; Somatic complaints; Self-rated health; Elderly; Accessibility; Non-adherence; Lithuania
The Ras/Raf/MEK/ERK and PI3K/PTEN/Akt/mTOR cascades are often activated by genetic alterations in upstream signaling molecules such as receptor tyrosine kinases (RTK). Targeting these pathways is often complex and can result in pathway activation depending on the presence of upstream mutations (e.g., Raf inhibitors induce Raf activation in cells with wild type (WT) RAF in the presence of mutant, activated RAS) and rapamycin can induce Akt activation. Targeting with inhibitors directed at two constituents of the same pathway or two different signaling pathways may be a more effective approach. This review will first evaluate potential uses of Raf, MEK, PI3K, Akt and mTOR inhibitors that have been investigated in pre-clinical and clinical investigations and then discuss how cancers can become insensitive to various inhibitors and potential strategies to overcome this resistance.
Targeted Therapy; Therapy Resistance; Cancer Stem Cells; Raf; Akt; PI3K; mTOR
Neutrophil gelatinase-associated lipocalin (NGAL, a.k.a Lnc2) is a member of the lipocalin family which has diverse roles including stabilizing matrix metalloproteinase-9 from auto-degradation and as siderocalins which are important in the transport of iron. NGAL also has important biological functions involved in immunity and inflammation as well as responses to kidney damage. NGAL expression has also been associated with certain neoplasia and is important in the metastasis of breast cancer. Many advanced cancer patients have elevated levels of NGAL in their urine and it has been proposed that NGAL may be a prognostic indicator for certain cancers (e.g. breast, brain, and others). NGAL expression is detected in response to various chemotherapeutic drugs including doxorubicin and docetaxel. We were interested in the roles of NGAL expression in cancer and whether it is associated with chemotherapeutic drug resistance. In the present study, we investigated whether increased NGAL expression led to resistance to the chemotherapeutic drug doxorubicin in normal breast epithelial cells (MCF-10A), breast cancer cells (MCF-7), and colorectal cancer cells (HT-29). We infected the various cell lines with a retrovirus encoding NGAL which we constructed. Increased NGAL expression was readily detected in the NGAL-infected cells but not the empty vector-infected cells. However, increased NGAL expression did not alter the sensitivity of the cells to the chemotherapeutic drug doxorubicin. Thus, although NGAL expression is often detected after chemotherapeutic drug treatment, it by itself, does not lead to doxorubicin resistance.
NGAL; Lcn2; Doxorubicin; lipocalins; siderocalins; iron transport; MMP-9; drug resistance
The Ras/Raf/MEK/ERK and PI3K/PTEN/Akt/mTOR cascades are often activated by genetic alterations in upstream signaling molecules such as receptor tyrosine kinases (RTK). Certain components of these pathways, RAS, NF1, BRAF, MEK1, DUSP5, PP2A, PIK3CA, PIK3R1, PIK3R4, PIK3R5, IRS4, AKT, NFKB1, MTOR, PTEN, TSC1, and TSC2 may also be activated/inactivated by mutations or epigenetic silencing. Upstream mutations in one signaling pathway or even in downstream components of the same pathway can alter the sensitivity of the cells to certain small molecule inhibitors. These pathways have profound effects on proliferative, apoptotic and differentiation pathways. Dysregulation of components of these cascades can contribute to: resistance to other pathway inhibitors, chemotherapeutic drug resistance, premature aging as well as other diseases. This review will first describe these pathways and discuss how genetic mutations and epigenetic alterations can result in resistance to various inhibitors.
Targeted Therapy; Therapy Resistance; Mutations; Raf; Akt; PI3K; mTOR
Hepatocellular carcinoma (HCC) is the most common liver cancer, accounting for 90% of primary liver cancers. In the last decade it has become one of the most frequently occurring tumors worldwide and is also considered to be the most lethal of the cancer systems, accounting for approximately one third of all malignancies.
Although the clinical diagnosis and management of early-stage HCC has improved significantly, HCC prognosis is still extremely poor. Furthermore, advanced HCC is a highly aggressive tumor with a poor or no response to common therapies. Therefore, new effective and well-tolerated therapy strategies are urgently needed.
Targeted therapies have entered the field of anti-neoplastic treatment and are being used on their own or in combination with conventional chemotherapy drugs. Molecular-targeted therapy holds great promise in the treatment of HCC. A new therapeutic opportunity for advanced HCC is the use of sorafenib (Nexavar). On the basis of the recent large randomized phase III study, the Sorafenib HCC Assessment Randomized Protocol (SHARP), sorafenib has been approved by the FDA for the treatment of advanced HCC. Sorafenib showed to be able to significantly increase survival in patients with advanced HCC, establishing a new standard of care. Despite this promising breakthrough, patients with HCC still have a dismal prognosis, as it is currently the major cause of death in cirrhotic patients. Nevertheless, the successful results of the SHARP trial underscore the need for a comprehensive understanding of the molecular pathogenesis of this devastating disease.
In this review we summarize the most important studies on the signaling pathways implicated in the pathogenesis of HCC, as well as the newest emerging drugs and their potential use in HCC management.
HCC; targeted therapy; VEGF; Ras/Raf/MEK/ERK; PI3K/Akt/PTEN/mTOR; signal transduction inhibitors; cancer
Assessment of US ability to identify subcutaneous nodular lesions using conventional B mode imaging (CBMI) and tissue second harmonic imaging (THI).
Materials and Methods
Three different types of equipment were used (Philips Envisor HDC, Philips HD 11 XE and GE Logic E) with 12–13 MHz probes and THI probes with variable frequency. One experienced operator studied 31 patients (24 women, 7 men, mean age 49 ± 15) with 52 subcutaneous nodular lesions of which 43 were palpable and 9 were nonpalpable. Statistical analysis was carried out using chi-square test.
19/52 subcutaneous nodular lesions were hyperechoic, 10/52 were isoechoic and 23/52 were hypoechoic. Of the hyperechoic nodules, 8/19 (42%) (p < 0.005) were not detected using THI, as they “disappeared” when THI was activated. Of the isoechoic nodules only 1/10 was not detected using THI, and of the hypoechoic nodules only 2/23 were not detected. Of the nodular lesions detected using CBMI and also using THI (41/52), 16/41 were shown more clearly using THI than using BMCI. No nodule was detected with the exclusive use of THI.
The statistical significance of the “disappearing” lesions (p < 0.005), mainly hyperechoic (42%), at the activation of THI must lead to a reconsideration of routine activation of THI during the entire US examination in the evaluation of subcutaneous lesions in order to avoid the risk of missing important lesions. The present results suggest that both BMCI and THI should be used in the study of subcutaneous lesions.
Ultrasound; Harmonic imaging; Contrast resolution; Subcutaneous tumors
Aging of the world's population represents one of the most remarkable success stories of medicine and of humankind, but it is also a source of various challenges. The aim of the collaborative cross-cultural European study of adult well being (ESAW) is to frame the concept of aging successfully within a causal model that embraces physical health and functional status, cognitive efficacy, material security, social support resources, and life activity. Within the framework of this project, we show here that the degree of heterogeneity among people who view aging in a positive light is significantly lower than the degree of heterogeneity of those who hold a negative perception of aging. We base this conclusion on our analysis of a survey involving 12,478 people aged 50 to 90 from six West European countries. We treat the survey database as a bipartite network in which individual respondents are linked to the actual answers they provide. Taking this perspective allows us to construct a projected network of respondents in which each link indicates a statistically validated similarity of answers profile between the connected respondents, and to identify clusters of individuals independently of demographics. We show that mental and physical well-being are key factors determining a positive perception of aging. We further observe that psychological aspects, like self-esteem and resilience, and the nationality of respondents are relevant aspects to discriminate among participants who indicate positive perception of aging.
Health and social services provided at home are becoming increasingly important. Hence, there is a need for information on home care in Europe. The objective of this literature review was to respond to this need by systematically describing what has been reported on home care in Europe in the scientific literature over the past decade.
A systematic literature search was performed for papers on home care published in English, using the following data bases: Cinahl, the Cochrane Library, Embase, Medline, PsycINFO, Sociological Abstracts, Social Services Abstracts, and Social Care Online. Studies were only included if they complied with the definition of home care, were published between January 1998 and October 2009, and dealt with at least one of the 31 specified countries. Clinical interventions, instrument developments, local projects and reviews were excluded. The data extracted included: the characteristics of the study and aspects of home care 'policy & regulation', 'financing', 'organisation & service delivery', and 'clients & informal carers'.
Seventy-four out of 5,133 potentially relevant studies met the inclusion criteria, providing information on 18 countries. Many focused on the characteristics of home care recipients and on the organisation of home care. Geographical inequalities, market forces, quality and integration of services were also among the issues frequently discussed.
Home care systems appeared to differ both between and within countries. The papers included, however, provided only a limited picture of home care. Many studies only focused on one aspect of the home care system and international comparative studies were rare. Furthermore, little information emerged on home care financing and on home care in general in Eastern Europe. This review clearly shows the need for more scientific publications on home care, especially studies comparing countries. A comprehensive and more complete insight into the state of home care in Europe requires the gathering of information using a uniform framework and methodology.
home care; European Union; care systems; international comparison
Dysregulated signaling through the Ras/Raf/MEK/ERK and PI3K/PTEN/Akt/mTOR pathways is often the result of genetic alterations in critical components in these pathways or upstream activators. Unrestricted cellular proliferation and decreased sensitivity to apoptotic-inducing agents are typically associated with activation of these pro-survival pathways. This review discusses the functions these pathways have in normal and neoplastic tissue growth and how they contribute to resistance to apoptotic stimuli. Crosstalk and commonly identified mutations that occur within these pathways that contribute to abnormal activation and cancer growth will also be addressed. Finally the recently described roles of these pathways in cancer stem cells, cellular senescence and aging will be evaluated. Controlling the expression of these pathways could ameliorate human health.
Raf; MEK; PI3K; mTOR; cancer; kinases; protein phosphorylation; signal transduction; apoptosis
The Ras/Raf/MEK/ERK and PI3K/PTEN/Akt/mTOR cascades are often activated by genetic alterations in upstream signaling molecules such as receptor tyrosine kinases (RTK). Integral components of these pathways, Ras, B-Raf, PI3K, and PTEN are also activated/inactivated by mutations. These pathways have profound effects on proliferative, apoptotic and differentiation pathways. Dysregulation of these pathways can contribute to chemotherapeutic drug resistance, proliferation of cancer initiating cells (CICs) and premature aging. This review will evaluate more recently described potential uses of MEK, PI3K, Akt and mTOR inhibitors in the proliferation of malignant cells, suppression of CICs, cellular senescence and prevention of aging. Ras/Raf/MEK/ERK and Ras/PI3K/PTEN/Akt/mTOR pathways play key roles in the regulation of normal and malignant cell growth. Inhibitors targeting these pathways have many potential uses from suppression of cancer, proliferative diseases as well as aging.
Targeted Therapy; Combination Therapy; Drug Resistance; Cancer Stem Cells; Aging; Senescence; Raf; Akt; PI3K; mTOR
Juvenile idiopathic arthritis (JIA) may cause damage to the temporomandibular joint (TMJ). In oligoarticular forms of JIA, TMJ involvement is often asymptomatic and consequently overlooked. The aim of this study was to evaluate the presence of TMJ joint effusion (JE) by ultrasonography (US) in patients with early arthritis.
Materials and methods
We examined 68 children (57 girls, 11 boys, age range 9.1–16.0 years, mean age 11.0 years) recently diagnosed with JIA. None had received any specific treatment for inflammation. Symptomatic TMJ involvement was diagnosed when one or more of the following were present: 1) recurrent pain (spontaneous or on movement of the jaw); 2) crepitation; 3) feeling of stiffness or fatigue of the jaw; 4) intermittent locking. US of the TMJ was performed in static and dynamic phases with a General Electric LOGIQ7 scanner and a linear transducer (8.5 MHz) positioned along the axis of the mandibular ramus. JE was diagnosed when the joint capsule was ≥1.5 mm thick.
Forty-six out (68%) of 68 children had US evidence of TMJ effusions (bilateral in 16 [35%] cases), but only 2/46 were symptomatic.
These data suggest that children with early stage oligoarticular JIA children are likely to have inflammation of the TMJs even in the absence of symptoms. US is a simple-to-use, noninvasive, radiation-free tool that can provide useful information in the assessment and follow-up of TMJ involvement in children and young adults with JIA.
Ultrasonography; TMJ; Oligo-articular onset; Early JIA
Abdominal wall actinomycosis is a rare disease frequently associated with the presence of an intra uterine device. We report on a case of a 47-year-old woman who had used an intrauterine device for many years and had removed it about a month prior to the identification of an abdominal wall abscess caused by Actinomyces israelii. The abscess mimicked a malignancy and the patient underwent a demolitive surgical treatment. The diagnosis was obtained only after histopathological examination. Postoperatively, the patient developed an infection of the wound which was treated with daily medication. The combination of long-term high dose antibiotic therapy with surgery led to successful treatment.
Actinomycosis; Abdominal wall; Intra uterine device; Abscess; Neoplasm
In systemic sclerosis (SSc), joint involvement may reduce the functional capacity of the hands. Intravenous immunoglobulins have previously been shown to benefit patients with SSc.
To verify the efficacy of intravenous immunoglobulins on joint involvement and function in SSc.
Patients and methods
7 women with SSc, 5 with limited and 2 with diffuse SSc, with a severe and refractory joint involvement were enrolled in the study. Methotrexate and cyclophosphamide pulse therapy did not ameliorate joint symptoms. Hence, intravenous immunoglobulins therapy was prescribed at a dosage of 2 g/kg body weight during 4 days/month for six consecutive courses. The presence of joint tenderness and swelling, and articular deformities (due to primary joint involvement and not due to skin and subcutaneous changes) were evaluated. Before and after 6 months of treatment, patients were subjected to (1) Ritchie Index (RI) evaluation of joint involvement; (2) Dreiser Algo‐Functional Index (IAFD) evaluation of hand joint function; (3) pain visual analogue scale (VAS) to measure joint pain; (4) Health Assessment Questionnaire (HAQ) to evaluate the limitations in everyday living and physical disability; and (5) modified Rodnan Skin Score for skin involvement.
After 6 months of intravenous immunoglobulins therapy, joint pain and tenderness, measured with the VAS, decreased significantly (p<0.03), and hand function (IAFD) improved significantly (p<0.02), together with the quality of life (HAQ; p<0.03). All patients significantly improved, except for one. The skin score after 6 months of intravenous immunoglobulins therapy was significantly reduced (p<0.003).
This pilot study suggests that intravenous immunoglobulins may reduce joint pain and tenderness, with a significant recovery of joint function in patients with SSc with severe and refractory joint involvement. The cost of intravenous immunoglobulins might limit their use only to patients who failed disease‐modifying antirheumatic drugs.
Ovarian cysts are the most common cause of pelvic masses in women, and in the majority of the cases, women are in their fertile age. Today, the surgical treatment has become more conservative and less invasive; hence, a laparoscopic approach in the presence of benign cysts has become a gold standard. Herein, we report a case of a 21-year-old woman referred to our Surgical Department for an abdominal mass, discovered with a computerised tomographic scan, of 20 ×10 × 25 cm arising from the left ovary, treated with the laparoscopic approach.
Benign ovarian cyst; laparoscopy; ovary
To test five hypotheses on Post-traumatic stress disorder (PTSD): 1) Is PTSD the most prevalent disorder after trauma? 2) Is the proximity to the disaster related to the risk of PTSD? 3) Is PTSD associated with child mourning or separation, previous stress, or familiarity for psychiatric disorders? 4) Does the exposition to trauma increase substance abuse or somatization? 5) Can episodic trauma cause long-lasting psychiatric morbidity?
Clinical assessment of subjects exposed to an explosion in a building caused by a gas-leak. Best estimate clinical diagnoses were made according to DSM-IV-TR criteria. The Zung Depression Rating Scale, the Zung Anxiety Rating Scale, and the Clinician Administered Post Traumatic Stress Disorder Scale were used in the clinical assessment. Statistical analysis was performed by means of t-test with Bonferroni's correction on continuous variables and χ2 or Fisher test on categorical variables.
PTSD was the most prevalent disorder after trauma, diagnosed in 32 (36.8%) subjects. The subjects who had not seen dead or injured people were more likely to receive no psychiatric diagnosis. Civil status, parenthood, death of relatives in the disaster, personal injuries, history of child mourning or separation, of previous stress, as well as familiarity for any psychiatric disorder or substance use disorder were not related with the rate of ascertained psychiatric diagnoses. Nearly two years after trauma, most of patients who had suffered PTSD still met PTSD criteria.
The 1st and the 5th hypotheses were corroborated, the 3rd and the 4th hypotheses were not confirmed. The 2nd hypothesis was partially confirmed.
Streptococcus pneumoniae pilus islet-1 (PI-1)-encoded pilus enhances in vitro adhesion to the respiratory epithelium and may contribute to pneumococcal nasopharyngeal colonization and transmission. The pilus subunits are regarded as potential protein vaccine candidates. In this study, we sought to determine PI-1 prevalence in carried pneumococcal isolates and explore its relationship with transmissibility or carriage duration. We studied 896 pneumococcal isolates collected during a longitudinal carriage study that included monthly nasopharyngeal swabbing of 234 infants and their mothers between the ages of 1 and 24 months. These were cultured according to the WHO pneumococcal carriage detection protocol. PI-1 PCR and genotyping by multilocus sequence typing were performed on isolates chosen according to specific carriage and transmission definitions. Overall, 35.2% of the isolates were PI-1-positive, but PI-1 presence was restricted to ten of the 34 serotypes studied and was most frequently associated with serotypes 19F and 23F; 47.5% of transmitted and 43.3% of non-transmitted isolates were PI-1-positive (OR 1.2; 95% CI 0.8–1.7; p 0.4). The duration of first-ever infant pneumococcal carriage was significantly longer with PI-1-positive organisms, but this difference was not significant at the individual serotype level. In conclusion, PI-1 is commonly found in pneumococcal carriage isolates, but does not appear to be associated with pneumococcal transmissibility or carriage duration.
Carriage; carriage duration; colonization; PI-1; pilus-1; Streptococcus pneumoniae; transmission