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ABSTRACTPattern recognition receptors (PRRs) are responsible for Aspergillus fumigatusrecognition by innate immunity and its subsequent immune signaling. The triggering receptor expressed on myeloid cells 1 (TREM1) is a recently characterized pro-inflammatory receptor constitutively expressed on the surface of neutrophils and macrophages. A soluble form (sTREM1) of this protein that can be detected in human body fluids has been identified. Here we investigated the role of TREM1 during invasive pulmonary aspergillosis (IPA). IPA patients displayed significantly higher levels of sTREM1 in bronchoalveolar lavages when compared to control patients. Functional analysis in TREM1 showed that the levels of sTREM1 and TREM1 pathway-related cytokines were influenced by single nucleotide polymorphisms in TREM1. In addition, we confirmed a role of TREM1 on antifungal host defense against A. fumigatusin a murine model of IPA. TREM1 deficiency increased susceptibility to infection in the immunosuppressed murine host. Deletion of TREM1 showed delayed innate and adaptive immune responses and impaired pro-inflammatory cytokine responses. The absence of TREM1 in primary macrophages attenuated the TLR signaling by altering the expression of both receptor and effector proteins that are critical to the response against A. fumigatus. In this study, and for the first time, we demonstrate the key role for the TREM1 receptor pathway during IPA.

Acute bacterial meningitis (ABM) is a rare but disabling infectious condition that requires a performant multidisciplinary management approach. Between 70 and 90 adult patients are diagnosed with community-acquired ABM in Belgium annually, and reported case fatality rates range from 17 to 40%. The currently available guidelines provide evidence-based guidance on how to manage this disease. However, these guidelines do not translate the evidence to the daily practice at the emergency department in a Belgian healthcare context. We created a taskforce in University Hospitals Leuven consisting of experts with complementary expertise in managing this disease: neurology, neurosurgery, intensive care medicine, microbiology and infectious diseases. The taskforce agreed upon a flowchart containing seven management steps encompassing all relevant phases in emergency ABM management. In addition to the focus on timely and adequate initiation of antimicrobial treatment, the flowchart and protocol also provide guidance on practical hurdles such as how to assess the safety of performing a lumbar puncture and when to refer patients to the intensive care department. This protocol was implemented in University Hospitals Leuven and fosters inter-disciplinary coordination of ABM care.

ABSTRACTAzole-resistant Aspergillus fumigatusis an increasing worldwide problem with major clinical implications. Surveillance is warranted to guide clinicians to provide optimal treatment to patients. To investigate azole resistance in clinical Aspergillusisolates in our institution, a Belgian university hospital, we conducted a laboratory-based surveillance between June 2015 and October 2016. Two different approaches were used: a prospective culture-based surveillance using VIPcheck on unselected A. fumigatus(n= 109 patients, including 19 patients with proven or probable invasive aspergillosis [IA]), followed by molecular detection of mutations conferring azole resistance, and a retrospective detection of azole-resistant A. fumigatusin bronchoalveolar lavage fluid using the commercially available AsperGenius PCR (n= 100 patients, including 29 patients with proven or probable IA). By VIPcheck, 25 azole-resistant A. fumigatusspecimens were isolated from 14 patients (12.8%). Of these 14 patients, only 2 had proven or probable IA (10.5%). Mutations at the cyp51Agene were observed in 23 of the 25 A. fumigatusisolates; TR34/L98H was the most prevalent mutation (46.7%), followed by TR46/Y121F/T289A (26.7%). Twenty-seven (27%) patients were positive for the presence of Aspergillusspecies by AsperGenius PCR. A. fumigatuswas detected by AsperGenius in 20 patients, and 3 of these patients carried cyp51Amutations. Two patients had proven or probable IA and cyp51Amutation (11.7%). Our study has shown that the detection of azole-resistant A. fumigatusin clinical isolates was a frequent finding in our institution. Hence, a rapid method for resistance detection may be useful to improve patient management. Centers that care for immunocompromised patients should perform routine surveillance to determine their local epidemiology.

ABSTRACTInfection is an important complication in patients with hematologic malignancies or solid tumors undergoing intensive cytotoxic chemotherapy. In only 20 to 30% of the febrile neutropenic episodes, an infectious agent is detected by conventional cultures. In this prospective study, the performance of broad-range PCR coupled with electrospray ionization time of flight mass spectrometry (PCR/ESI-MS) technology was compared to conventional blood cultures (BC) in a consecutive series of samples from high-risk hematology patients. In 74 patients, BC and a whole-blood sample for PCR/ESI-MS (Iridica BAC BSI; Abbott, Carlsbad, CA, USA) were collected at the start of each febrile neutropenic episode and, in case of persistent fever, also at day 5. During 100 different febrile episodes, 105 blood samples were collected and analyzed by PCR/ESI-MS. There was evidence of a bloodstream infection (BSI) in 36/105 cases (34%), based on 14 cases with both PCR/ESI-MS and BC positivity, 17 cases with BC positivity only, and 5 cases with PCR/ESI-MS positivity only. The sensitivity of PCR/ESI-MS was 45%, specificity was 93%, and the negative predictive value was 80% compared to blood culture. PCR/ESI-MS detected definite pathogens (Fusobacterium nucleatumand Streptococcus pneumoniae) missed by BC, whereas it missed both Gram-negative and Gram-positive organisms detected by BC. PCR/ESI-MS testing detected additional microorganisms but showed a low sensitivity (45%) compared to BC in neutropenic patients. Our results indicate a lower concordance between BC and PCR/ESI-MS in the neutropenic population than what has been previously reported in other patient groups with normal white blood cell distribution, and a lower sensitivity than other PCR-based methods.

ABSTRACTTesting cerebrospinal fluid (CSF) for the presence of galactomannan (GM) antigen may help in diagnosing cerebral aspergillosis (CA). However, the use of the CSF GM test as a diagnostic test has been little studied. We evaluated its diagnostic performance by comparing the CSF GM optical density indexes (ODI) at different cutoffs in patients with probable and proven CA to those in patients without CA. Patients from 2 tertiary referral hospitals with suspected CA between 2004 and 2014 and in whom CSF GM ODI had been determined were selected. European Organization for Research and Treatment of Cancer/Invasive Infectious Diseases Study Mycoses Group (EORTC/MSG) definitions of invasive aspergillosis and CA were used, but with the exclusion of the test to be validated (i.e., the CSF GM test) as a microbiological EORTC/MSG criterion. The study population consisted of 44 patients (4 with proven CA, 13 with probable CA, and 27 with no CA). Of the 17 patients with CA, 15 had a CSF GM ODI of =2.0. Of 27 patients without CA, 26 had a CSF GM ODI of <0.5 and 1 had a CSF GM ODI of 8.2. When a GM CSF ODI cutoff of 1.0 was used, the sensitivity, specificity, and positive and negative predictive values were 88.2%, 96.3%, 93.8%, and 92.9%, respectively. The same results were found when a CSF GM ODI cutoff of 0.5 or 2.0 was used. Testing GM in CSF has a high diagnostic performance for diagnosing CA and may be useful to diagnose or virtually rule out the infection without the need for a cerebral biopsy.

ABSTRACTA panel of new cytomegalovirus (CMV) assays for use on the Architect instrument has been developed, including a CMV avidity assay based on a new technology. The purpose of this study was to compare the performance characteristics of the fully automated CMV immunoglobulin M (IgM), IgG, and IgG avidity tests on the Architect instrument with those of other available assays. A total of 503 consecutive fresh patient serum specimens (routine serum specimens) and 96 serum specimens from 33 pregnant women with a recent CMV primary infection (seroconversion serum specimens) were tested for CMV IgM and IgG by the Architect (Abbott), Vidas (BioMe´rieux), and Enzygnost (Siemens) assays. The seroconversion sera and 100 preselected serum specimens IgM negative and IgG positive by the AxSYM assay were also tested by the IgG avidity tests on the Architect and Vidas instruments. The relative agreements for CMV IgM determination with routine sera between the Architect assay and the Vidas, Enzygnost, and AxSYM assays were 97%, 94%, and 93%, respectively, for the CMV IgM tests and 99%, 98%, and 98%, respectively, for the CMV IgG tests. The specificities of the CMV IgG avidity test were 98% for the Architect assay and 76% for the Vidas assay. No high CMV IgG avidity test results were found within the first 3 months after seroconversion by either of those assays. The correlation between the results of the newly developed CMV IgM and IgG tests on the Architect instrument with the Vidas and Enzygnost assays was excellent (=94%). The CMV IgG avidity test reliably excluded patients with recent infections and showed an excellent specificity (98%).

The aim of this study was to evaluate the diagnostic reliability and prognostic significance of the quantification of cytomegalovirus (CMV) DNA in amniotic fluid (AF). We retrospectively reviewed the results for 282 amniotic fluid samples that had been tested for CMV by a quantitative real-time PCR. We observed three cases in which no CMV genomes were detected in the AF but in which the children were nevertheless congenitally infected. Hence, we conclude that a negative result by PCR for CMV in AF cannot rule out the possibility of congenital infection. No false-positive PCR results were observed. A correlation between the CMV viral load in AF and the fetal and neonatal outcomes could not be demonstrated in our study. Instead, a correlation was found between the CMV viral load and the gestational age at the time of amniocentesis.

AbstractBackground: Most girls with Turner syndrome (TS) are intensively followed by paediatricians, but are lost to follow-up when they reach adulthood. To gain insight into the adult medical and psychosocial situation, we performed a survey in young adult TS patients. Patients and Methods: A questionnaire concerning current health status, education, occupation and living situation was sent to 160 young adult TS women, all treated during childhood with GH and oestrogen if needed. Results: We received 102 completed questionnaires. Mean ± SD age at reception of the questionnaire was 23.4 ± 3.3 years, height 153.3 ± 5.2 cm, body mass index 23.7 ± 4.9 kg/m². Age and auxological parameters were comparable between responders and non-responders. Thirteen (12.7%) responders were not under regular medical care; 15 (14.7%) were seen by a general practitioner, while 28 (27.4%) needed several specialists. Forty-one (40.2%) patients reported health problems. The most frequently reported problem was hypertension (10.7%), followed by hypothyroidism (5.8%) and back problems (4.9%). Twenty-four (23.5%) of the 41 patients were taking medication for the indicated health problems. Twenty-six (25.5%) women had undergone spontaneous puberty; 16 of them reported spontaneous menstruations while 10 received oestrogen replacement therapy. Of the 76 women with induced puberty, 11 (14.5%) were not taking any oestrogen anymore. Compared with the general population, more TS women attended university and more obtained higher education. Forty-six women (45.1%) were working full-time, 7 (6.9%) were unemployed, and 4 (3.9%) received an allocation. Seventy (68.6%) patients were still living with their parents, while 18 (17.6%) were living together or married, and 14 (13.7%) were living alone. Conclusions: The transition of adolescents with TS to adult medical care is not optimal in Belgium. Although 40.2% of these young women reported health problems, 12.7% did not consult any physician. Many TS women did not take oestrogen replacement therapy. A specialized multidisciplinary approach for adults with TS is needed in order to optimize health and psychosocial status in these women.Copyright © 2004 S. Karger AG, Basel

Background:Most girls with Turner syndrome (TS) are intensively followed by paediatricians, but are lost to follow-up when they reach adulthood. To gain insight into the adult medical and psychosocial situation, we performed a survey in young adult TS patients. Patients and Methods:A questionnaire concerning current health status, education, occupation and living situation was sent to 160 young adult TS women, all treated during childhood with GH and oestrogen if needed. Results:We received 102 completed questionnaires. Mean ± SD age at reception of the questionnaire was 23.4 ± 3.3 years, height 153.3 ± 5.2 cm, body mass index 23.7 ± 4.9 kg/m². Age and auxological parameters were comparable between responders and non-responders. Thirteen (12.7%) responders were not under regular medical care; 15 (14.7%) were seen by a general practitioner, while 28 (27.4%) needed several specialists. Forty-one (40.2%) patients reported health problems. The most frequently reported problem was hypertension (10.7%), followed by hypothyroidism (5.8%) and back problems (4.9%). Twenty-four (23.5%) of the 41 patients were taking medication for the indicated health problems. Twenty-six (25.5%) women had undergone spontaneous puberty; 16 of them reported spontaneous menstruations while 10 received oestrogen replacement therapy. Of the 76 women with induced puberty, 11 (14.5%) were not taking any oestrogen anymore. Compared with the general population, more TS women attended university and more obtained higher education. Forty-six women (45.1%) were working full-time, 7 (6.9%) were unemployed, and 4 (3.9%) received an allocation. Seventy (68.6%) patients were still living with their parents, while 18 (17.6%) were living together or married, and 14 (13.7%) were living alone. Conclusions:The transition of adolescents with TS to adult medical care is not optimal in Belgium. Although 40.2% of these young women reported health problems, 12.7% did not consult any physician. Many TS women did not take oestrogen replacement therapy. A specialized multidisciplinary approach for adults with TS is needed in order to optimize health and psychosocial status in these women.

We have investigated the influence of subinhibitory concentrations of erythromycin on the interaction between Streptococcus pneumoniae and human respiratory epithelial cells. Confluent in vitro cell cultures were inoculated with erythromycin-resistant S. pneumoniae and incubated for 24 h. Erythromycin significantly reduced adherence of the pneumococci after 4 h and 24 h: 4.0% +/- 0.7% (mean +/- S.E.M. ) of the pneumococci adhered to the epithelial cells in medium with erythromycin, compared with 7.7% +/- 0.8% in medium without erythromycin (P: = 0.002) after 4 h, and the corresponding values after 24 h were 24.2% +/- 5.3% and 38.4% +/- 5.0%, respectively (P: = 0.038). Disruption of epithelial integrity by S. pneumoniae, measured as the decrease in transepithelial electrical resistance, was delayed in the presence of erythromycin. Neither addition of erythromycin to the culture medium nor infection of the cell cultures with pneumococci significantly affected secretion of interleukin-8 by the epithelial cells. Addition of erythromycin to a pneumococcal suspension in cell culture medium without respiratory epithelial cells almost completely prevented the release of pneumolysin. We conclude that erythromycin at subinhibitory concentrations reduces the adherence to and disruption of respiratory epithelial cells by S. pneumoniae, possibly by interfering with pneumolysin release.

AbstractThe aim of the present study was to evaluate the behavioral and affective characteristics and the changes in psychosocial functioning resulting from precocious puberty in 15 girls with central precocious puberty treated for 2 y using the GnRH agonist long‐acting triptorelin, and in 5 untreated girls. After diagnosis of precocious puberty at 6.6–10.4 y of age, height, weight and pubertal development were evaluated at 3‐month intervals over 2 y. Semi‐structured interviews were carried out with the patient, the parents and the pediatric endocrinologists at 1, 8, 16 and 24 months after diagnosis. Standardized questionnaires (Child Behavior Checklist, Self‐esteem Inventory) were administered at 1 and 24 months or 16 and 24 months, respectively. There was a mean 1.5‐y delay between the observation of signs of puberty as reported by the parents and the diagnosis of precocious puberty at the first consultation of a pediatric endocrinologist. Before follow‐up, all 20 girls were very concerned about physical differences from peers, particularly breast development. During therapy, breast regression to minimal or absent development occurred in 5/15 treated patients, who then no longer felt embarrassed about pubertal development in contrast to the other patients. Fear of sexuality remained obvious throughout the study in most patients. Feelings of loneliness and exemplary behavior were observed and tended to decrease in the treated patients and to increase in the untreated patients. Elevated scores of withdrawal, anxiety/depression and somatic complaints at Child Behavior Checklist were still observed after 2 y. These changes in behavioral and affective characteristics appeared to be related neither to height and weight, nor to development of pubic hair, which progressed in most patients. After 2 y, the physical differences remained a concern for 13 girls and the risk of short adult stature for 6. In summary, some behavioral and affective characteristics and particularities in psychosocial functioning are observed in girls with precocious puberty. During treatment with long acting triptorelin, problematic behavior and functioning decrease slightly, particularly in the few girls showing breast regression to minimal or absent development.

Invasive aspergillosis (IA) is a life-threatening infection that affects an increasing number of patients undergoing chemotherapy or allo-transplantation, and recent studies have shown that genetic factors contribute to disease susceptibility. In this two-stage, population-based, case-control study, we evaluated whether 7 potentially functional single nucleotide polymorphisms (SNPs) within the ARNT2and CX3CR1genes influence the risk of IA in high-risk hematological patients.

The genetic basis of macrolide resistance was characterized in 59 Streptococcus pneumoniae isolates. All isolates were collected in 1995 and 1997 and were from invasive infections. The majority of the isolates (54 of 59 isolates) were erythromycin and clindamycin resistant (MLS(B)-phenotype) and carried the ermAM gene. Five isolates were erythromycin resistant but clindamycin susceptible (M-phenotype). Using PCR the mefE gene was detected in these five isolates. Contrary to the situation found in Canada and the USA, mefE-mediated erythromycin resistance in S. pneumoniae is uncommon in Belgium.