Identification and mechanism determination of the efflux pump subunit amrB gene mutations linked to gentamicin susceptibility in clinical Burkholderia pseudomallei from Malaysian Borneo

The bacterium Burkholderia pseudomallei is typically resistant to gentamicin but rare susceptible strains have been isolated in certain regions, such as Thailand and Sarawak, Malaysia. Recently, several amino acid substitutions have been reported in the amrB gene (a subunit of the amrAB-oprA efflux pump gene) that confer gentamicin susceptibility. However, information regarding the mechanism of the substitutions conferring the susceptibility is lacking. To understand the mechanism of amino acid substitution that confers susceptibility, this study identifies the corresponding mutations in clinical gentamicin-susceptible B. pseudomallei isolates from the Malaysian Borneo (n = 46; Sarawak: 5; Sabah: 41). Three phenotypically confirmed gentamicin-susceptible (GENs) strains from Sarawak, Malaysia, were screened for mutations in the amrB gene using gene sequences of gentamicin-resistant (GENr) strains (QEH 56, QEH 57, QEH20, and QEH26) and publicly available sequences (AF072887.1 and BX571965.1) as the comparator. The effect of missense mutations on the stability of the AmrB protein was determined by calculating the average energy change value (ΔΔG). Mutagenesis analysis identified a polymorphism-associated mutation, g.1056 T > G, a possible susceptible-associated in-frame deletion, Delta V412, and a previously confirmed susceptible-associated amino acid substitution, T368R, in each of the three GENs isolates. The contribution of Delta V412 needs further confirmation by experimental mutagenesis analysis. The mechanism by which T368R confers susceptibility, as elucidated by in silico mutagenesis analysis using AmrB-modeled protein structures, is proposed to be due to the location of T368R in a highly conserved region, rather than destabilization of the AmrB protein structure.

Improving the clinical recognition, prognosis, and treatment of melioidosis through epidemiology and clinical findings: The Sabah perspective

INTRODUCTION

Melioidosis is a deadly endemic disease in northern Australia and Southeast Asia, including Sabah, Malaysia, which is caused by the bacterium Burkholderia pseudomallei. It contributes to high fatality rates, mainly due to misdiagnosis leading to the wrong treatment being administered to the patients. Local epidemiology and data on clinical features could assist clinicians during diagnosis and treatment. However, these details are still scarce, particularly in Sabah.

METHODS

A retrospective study of 246 culture-confirmed melioidosis cases in Queen Elizabeth Hospital, Sabah, Malaysia was performed between 2016 and 2018. The epidemiological data and clinical and laboratory findings were extracted and analysed.

RESULTS

The annual incidence of culture-confirmed melioidosis cases was estimated to be 4.97 per 100,000 people. The mean age of the patients was 50±15 years. Males and members of the Kadazan-Dusun ethnic group accounted for the majority of the melioidosis cases. The odds ratio analysis indicated that bacteraemic melioidosis in this region was significantly associated with fever (76%), and patients having at least one underlying illness (43%), including diabetes mellitus (32%). Sixty-eight patients (28%) succumbed to melioidosis. Contrary to what is known regarding factors that promote bacteraemic melioidosis, neither patients with fever nor patients with at least one comorbid disease, including diabetes mellitus, were significantly associated with death from melioidosis. There was no statistically significant difference between patients without comorbidities (24, 27%) and those with at least one comorbid disease (26, 25%), including diabetes mellitus (18, 23%). The odds ratios indicate that melioidosis mortality in this region is related to patients showing respiratory organ-associated symptoms (29%), bacteraemia (30%), and septic shock (47%). Burkholderia pseudomallei isolates in this study were highly susceptible to ceftazidime (100%), imipenem (100%), and trimethoprim-sulfamethoxazole (98%).

CONCLUSIONS

Information obtained from this study can be used by clinicians to recognise individuals with the highest risk of acquiring melioidosis, estimate an accurate prognosis, and provide effective treatment for melioidosis patients to reduce death from melioidosis.

Nutritional impact of excluding red meat from the Canadian diet

The objective of the study was to examine differences in nutrient intake between consumers and non-consumers of red meat and to assess nutritional adequacy of consumers relative to Recommended Daily Allowance (RDA) in Canada. Matching estimators were used to identify differences in nutrient intake between the two groups. Statistically significant differences were observed in nutrient intake between red meat consumers and non-consumers, including lower daily intake of protein, riboflavin, niacin, vitamin D, and zinc and a higher daily intake of dietary fiber, folate, and magnesium among Canadians who did not consume red meat. Further, red meat consumers and non-consumers had nutrient intakes below RDA for dietary energy, fiber, and calcium. While individuals who did not consume red meat were at increased risk of calcium, vitamin D, energy, and potassium inadequacy, those who consumed red meat were at increased risk of dietary fiber, vitamin A, and magnesium inadequacy.

Catalytic pyrolysis of high-density polyethylene over nickel-waste chicken eggshell/HZSM-5

The main objective of the current work is to investigate the effect of nickel-waste chicken eggshell modified Hydrogen exchanged Zeolite Socony Mobil-5 (Ni-WCE/HZSM-5) on pyrolysis of high-density polyethylene (HDPE). Ni-WCE/HZSM-5 was synthesized via the impregnation incipient wetness (IWI) method with Ni and WCE mass loading of 4 and 12 wt% respectively. HZSM-5, CaO, WCE, WCE/HZSM-5, and Ni/HZSM-5 were prepared for comparison purposes with Ni-WCE/HZSM-5. All the synthesized catalysts were characterized for phase analysis, metal loading, surface morphology, and textural properties. The impregnation of nickel and WCE had significantly affected the original framework of HZSM-5, where the crystallinity percentage and average crystal size of HZSM-5 dropped to 44.97% and increased to 47.90 nm respectively. The surface morphology of HZSM-5 has drastically changed from a cubic-like shape into a spider web-like surface after the impregnation of WCE. The BET surface area of HZSM-5 has been lowered due to the impregnation of nickel and WCE, but the total pore volume has increased greatly from 0.2291 cm³/g to 0.2621 cm³/g. The catalyst performance was investigated in the pyrolysis of HDPE via a fixed bed reactor and the pyrolysis oil was further analysed to evaluate the distribution of C₆ to C₉> hydrocarbons. Among the tested catalytic samples, the highest pyrolysis oil yield was achieved by WCE (80%) followed by CaO (78%), WCE/HZSM-5 (63%), HZSM-5 (61%), Ni/HZSM-5 (44%) and Ni-WCE/HZSM-5 (50%). For hydrocarbon distribution in pyrolysis oil, the Ni/HZSM-5 produced the highest of total C₆ and C₇ hydrocarbons at 12% and 27% respectively followed by WCE/HZSM-5 (4% and 20%), non-catalytic (5% and 13%), Ni-WCE/HZSM-5 (0% and 15%), WCE (0% and 10%), HZSM-5 (0% and 6%) and CaO (0% and 0%).

Promoting a well-dispersion of MoO3 nanoparticles on fibrous silica catalyst via one-pot synthesis for enhanced photoredox environmental pollutants efficiency

The coexistence of pharmaceutical compounds and heavy metals in the aquatic environment has resulted in complications in the treatment process and thus, causing uproar among the citizens. The radical-based photocatalysis technology has aroused as an excellent method to eliminate both heavy metal and pharmaceutical compounds in the water. Herein, reported the utilization of the microemulsion technique for the preparation of nanoporous fibrous silica-molybdenum oxide (FSMo) towards simultaneous photocatalytic abatement of hexavalent chromium (Cr(VI)) and tetracycline (TC). The FESEM analysis showed the spherical morphology of the FSMo catalyst with dendrimeric silica fiber. The synthesized FSMo catalyst exhibited narrowed bandgap, high crystallinity, and well Mo element dispersion for enhanced photo-redox of Cr(VI) and TC. Remarkably, simultaneous remediation of the Cr(VI) and TC over FSMo demonstrated superior photocatalytic efficiency, 69% and 75%, respectively, than in the individual system, possibly due to the effective separation of photoinduced charges. The introduction of the Mo element to the silica framework via microemulsion technique demonstrated better dispersion of Mo compared to the incipient wetness impregnation method and thus, yielded higher photocatalytic activity towards simultaneous removal of TC and Cr(VI). Besides, quenching experiments revealed the electrons and holes as the active species that play a dominant role in the simultaneous photo-redox of Cr(VI) and TC. Lastly, the FSMo catalyst demonstrated high stability after four continuous cycles of simultaneous photocatalysis reactions, implying its potential as a suitable material for practical wastewater treatments.

National audit of non-melanoma skin cancer excisions performed by plastic surgery in the UK

A national, multi-centre audit of non-melanoma skin cancer excisions by plastic surgery.

Styrylpyrone Derivative (SPD) Extracted from Goniothalamus umbrosus Binds to Dengue Virus Serotype-2 Envelope Protein and Inhibits Early Stage of Virus Replication

A study was conducted to investigate the anti-viral effect of a styrylpyrone derivative (SPD) called goniothalamin and the effects on the dengue virus serotype 2 (DENV-2) replication cycle. The SPD was prepared from the root of Goniothalamus umbrosus after purification with petroleum ether. The isolated SPD was then subjected to gas chromatography–mass spectrometry (GC-MS) and nuclear magnetic resonance (NMR) analyses for structure validation. The cytotoxicity of the SPD was evaluated using a cell viability assay, while the anti-viral activity of the SPD towards DENV-2 was confirmed by conducting a foci reduction assay which involved virus yield reduction, time-of-addition, and time removal assays. Transcriptomic analysis via quantitative real-time polymerase chain reaction (qRT-PCR) using the DENV-2 E gene was conducted to investigate the level of gene transcript. Immunocytochemistry analysis was used to investigate the effects of SPD treatment on protein E expression. Finally, software molecular docking of the SPD and E protein was also performed. The cytotoxicity assay confirmed that the SPD was not toxic to Vero cells, even at the highest concentration tested. In the time-of-addition assay, more than 80% foci reduction was observed when SPDs were administered at 2 h post-infection (hpi), and the reduction percentage then dropped with the delay of the treatment time, suggesting the inhibition of the early replication cycle. However, the time removal assay showed that more than 80% reduction could only be observed after 96 h post-treatment with the SPD. Treatment with the SPD reduced the progeny infectivity when treated for 24 h and was dose-dependent. The result showed that transcript level of the E gene in infected cells treated with the SPD was reduced compared to infected cells without treatment. In immunocytochemistry analysis, the DENV-2 E protein exhibited similar expression trends, shown by the gene transcription level. Molecular docking showed that the SPD can interact with E protein through hydrogen bonds and other interactions. Overall, this study showed that SPDs have the potential to be anti-DENV-2 via a reduction in viral progeny infectivity and a reduction in the expression of the DENV-2 E gene and protein at different phases of viral replication. SPDs should be further researched to be developed into an effective anti-viral treatment, particularly for early-phase dengue viral infection.

Cord Blood Thyroid Stimulating Hormone Values in Healthy Term Babies delivered at Abubakar Tafawa Balewa University Teaching Hospital Bauchi, Northeastern Nigeria

BACKGROUND

Congenital hypothyroidism is one of the most common preventable causes of mental retardation and clinical manifestations are often subtle or absent at birth and hence the need for screening. Implementation of newborn screening requires local normative values.

OBJECTIVES

To determine the normative values of cord Thyroid Stimulating Hormone (TSH) among term babies in Bauchi, Northeast Nigeria and compare it with that from other centers in Nigeria.

METHODOLOGY

Cord blood samples from 200 term babies were analyzed for TSH by Fluorescence Immunoassay technique in this descriptive cross-sectional study. A cut-off of >20 µIU/ml was used for recall. The mean and range were determined and compared with those of previous local studies using t-test. Impact of some maternal and infant factors on TSH was also assessed.

RESULTS

The overall mean (SD) cord TSH was 3.74 (±1.99) µIU/ ml and the range was 0.73 to 15.22 µIU/ml (2.5th to 97.5th centile) and none had TSH > 20 µIU/ml and hence our recall rate was 0%. The mean cord TSH was comparable to that reported by a lone local multicenter study (p = 0.120) but significantly different from that of 3 other local studies (p < 0.001). There was also no significant difference between the means of different gender, birth weight groups, mode of delivery, socio-economic classes, maternal age and parity.

CONCLUSION

The Cord blood TSH level of most term newborn in Bauchi, similar to other Nigerian studies, is < 10 µIU/ml with a few but significant percentage recording cord TSH level > 10 µIU/ml. Gender, birth weight, mode of delivery, socio-economic class, maternal age and parity were not significantly related to cord TSH level. The mean blood TSH values from different studies across the country tend to vary based on the assay technique. We recommend a nationwide multicenter study with a much larger sample size, lower cutoff value for recall and a unified sample processing laboratory if national normative values are to be developed.

True-positive reflex threshold value for HCV antibody screening test

Introduction: The use of a signal-to-cut-off ratio has been recommended by the Centre for Disease Control and Prevention to determine the need for further validation using a supplemental test. In this study, we aimed to determine the optimal true-positive signal-to-cut-off ratio for the ABBOTT ARCHITECT i2000SR immunoassay (Abbott Laboratories, Illinois, USA), using the Serodia® HCV particle agglutination (HCV-PA) assay (Fujirebio Inc, Tokyo, Japan) as the reference test for anti-HCV screening. Methodology: We analysed a total of 13,240 specimens using the ARCHITECT i2000SR immunoassay and subsequently subjected all the reactive specimens with a signal-to-cut-off ratio ≥ 1.00 (n = 267) to the Serodia® HCV-PA reference assay. Receiver operating characteristic (ROC) curve analysis was carried out and performance characteristics for each signal-to-cut-off ratio were determined. The selected signal-to-cut-off ratio value was then assessed using a line immunoassay (LIA) test. Results: ROC curve analysis determined that the optimal signal-to-cut-off ratio was 5.05, which gave the highest Youden’s Index (J) value of 0.89, with a sensitivity of 93.1% (88.9-97.2), a specificity of 96.0% (92.4-99.4), a positive predictive value of 96.4% (93.3-99.5), and a negative predictive value of 92.2% (87.5-96.8). Validation of the optimal S/Co value using the LIA test yielded an accuracy of 91.8%, with sensitivity and specificity values of 92.0% and 91.7%, respectively. Conclusions: The optimal signal-to-cut-off ratio value for the ARCHITECT i2000SR immunoassay, which was determined using HCV-PA assay as the reference test and validated using a HCV-LIA assay, showed high sensitivity and specificity, and may be used in routine anti-HCV screening.

314 Biodegradable Temporising Matrix (BTM) Use in a Traumatic Chest Wound: A Case Report

We describe the innovative use of biodegradable temporising matrix (BTM) in a large traumatic chest wound in a 23-year-old lady at the Welsh Centre for Burns and Plastic Surgery. The wound was sustained after the patient fell from a tractor into a large silage rake, resulting in injuries to her chest and limbs. Following meticulous debridement, the resulting full thickness skin defect measured 30x30 cm extending from the sternal notch to the upper abdomen, with bone, muscle, and breast tissue exposure. No donor sites for free flap reconstruction were available due to the limb injuries.

BTM is a recently developed synthetic dermal substitute and has been utilised to achieve soft tissue coverage in complex wounds i.e., post debridement in burns, traumatic injuries, and necrotising fasciitis. It was used in this case as it confers a number of advantages against skin graft alone such as reduced susceptibility to contracture and the ability to cover small areas of exposed bone. It also demonstrates reduced susceptibility to infection compared with other dermal substitutes.

To our knowledge, this is the first use of BTM to cover breast tissue. The central chest is a difficult anatomical region to reconstruct due to the importance of maintaining breast contour and avoiding wound contracture and deformity. The patient was closely followed up in dressing clinic and application of split skin autograft over the delaminated achieved an aesthetically excellent and functionally result, with breast contour maintained and full range of movement at the axilla.

Unveiling antimicrobial activity of microalgae Chlorella sorokiniana (UKM2), Chlorella sp. (UKM8) and Scenedesmus sp. (UKM9)

Microalgae represent promising sources of bioactive compounds for pharmaceutical and industrial applications. The emergence of antibiotic resistant bacteria leads to the need to explore new cost-effective, safe, and potent bioactive compounds from the microalgae. This study aimed to investigate the potential of local microalgae for their antimicrobial properties and bioactive compounds. Three local microalgae namely Chlorella sorokiniana (UKM2), Chlorella sp. UKM8, and Scenedesmus sp. UKM9 biomass methanol extracts (ME) were prepared and tested against Gram-positive and Gram-negative bacteria. Chlorella sp. UKM8-ME showed the highest antibacterial activity. UKM8-ME minimum inhibitory concentrations were in the range of 0.312 to 6.25 mg/mL. Cytotoxicity evaluation using MTT assay showed that the microalgae methanolic extracts did not exhibit cytotoxicity against Vero-cells. The UKM8-ME was mainly containing 28 compounds from the Gas Chromatography-Mass Spectrometry (GC–MS) analysis. Major compounds of UKM8-ME included phenol (18.5%), hexadecanoic acid (18.25%), phytol (14.43%), 9,12-octadecadienoic acid (13.69%), and bicyclo[3.1.1]heptane (7.23%), which have been previously described to possess antimicrobial activity. Hence, Chlorella sp. (UKM8) methanol extracts showed promising antibacterial activity. More comprehensive studies are required to purify these antimicrobial compounds and develop our understanding on their mechanism in UKM8-ME to unleash their specific potential.

Extended thromboprophylaxis post gynaecological cancer surgery; the effect of weight adjusted and fixed dose LMWH (Tinzaparin)

OBJECTIVE

Gynaecological cancer surgery is associated with high rates of venous thromboembolism (VTE) despite recommended prophylaxis. We sought to investigate the impact of extended prophylaxis with fixed dose and weight based LMWH in patients undergoing gynaecological cancer surgery.

METHODS

VTE rates were recorded in patients who received LMWH prophylaxis (4500 IU Tinzaparin once daily) for the duration of hospital stay (2006-2012) (n = 610) and were compared with VTE rates in patients who underwent surgery after the introduction of extended prophylaxis (3500/4500 IU Tinzaparin for patients with BMI < 40kg/m2 and 75 IU/kg for BMI > 40 kg/m2) (2012-2017) (n = 651). Peak (4 h) anti-Xa levels in a subset of patients were also evaluated.

RESULTS

73 (5.7%) cases of VTE were recorded during 1 year of follow-up. 20 cases occurred during hospital stay. There was no significant difference in the rate of VTE between the extended prophylaxis cohort and the standard prophylaxis cohort. 23/24 patients who developed VTE in the extended prophylaxis cohort received a fixed (4500 units) dose of Tinzaparin. 63% of patients who received a fixed LMWH dose had peak anti-Xa levels below the target range (0.2-0.4 IU/ml). Peak anti-Xa was lower in patients who subsequently developed VTE compared with those who received either fixed dose (P = 0.041) and weight adjusted Tinzaparin (P = 0.0006).

CONCLUSIONS

Extended prophylaxis with Tinzaparin does not significantly reduce VTE rates in gynaecological cancer patients post surgery. Peak anti-Xa levels may be suboptimal in many patients receiving a fixed LMWH dose. Further studies are required to determine whether weight adjusted doses of Tinzaparin may provide more effective prophylaxis following gynaecological cancer surgery.

Antitumor activity of ipilimumab or BRAF ± MEK inhibition after pembrolizumab treatment in patients with advanced melanoma: analysis from KEYNOTE-006

BACKGROUND

Antitumor activity of ipilimumab or BRAF ± MEK inhibitors (BRAFi ± MEKi) following pembrolizumab administration in melanoma is poorly characterized.

PATIENTS AND METHODS

In the phase III KEYNOTE-006 study, patients with unresectable stage III/IV melanoma received pembrolizumab (10 mg/kg) once every 2 or 3 weeks (Q3W) or ipilimumab (3 mg/kg) Q3W. The current post hoc analysis evaluates outcomes with ipilimumab or BRAFi ± MEKi as first subsequent systemic therapy after pembrolizumab administration and includes patients who completed or discontinued pembrolizumab after one or more dose. Pembrolizumab arms were pooled.

RESULTS

At data cut-off (4 December 2017), median follow-up was 46.9 months. Of 555 pembrolizumab-treated patients, first subsequent therapy was ipilimumab for 103 (18.6%) and BRAFi ± MEKi for 59 (10.6%) [33 received BRAFi + MEKi, 26 BRAFi alone; 37 (62.7%) were BRAFi ± MEKi naïve]. In the subsequent ipilimumab group, ORR with previous pembrolizumab was 17.5% [1 complete response (CR); 17 partial response (PR)]; 79.6% had discontinued pembrolizumab due to progressive disease (PD); median overall survival (OS) was 21.5 months. ORR with subsequent ipilimumab was 15.5%; 11/16 responses (8 CRs; 3 PRs) were ongoing. ORR with subsequent ipilimumab was 9.7% for patients with PD as best response to pembrolizumab. Median OS from ipilimumab initiation was 9.8 months. In the subsequent BRAFi ± MEKi group, ORR with previous pembrolizumab was 13.5% (8 PR); 76.3% had discontinued pembrolizumab due to PD; median OS was 17.9 months. ORR with subsequent BRAFi ± MEKi was 30.5%, 7/18 responses (4 CR, 3 PR) were ongoing. Median OS from BRAFi ± MEKi initiation was 12.9 months. ORR for BRAFi ± MEKi-naïve patients who received subsequent BRAFi ± MEKi was 43.2%; 6/16 were ongoing (3 CR, 3 PR).

CONCLUSIONS

Ipilimumab and BRAFi ± MEKi have antitumor activity as first subsequent therapy after pembrolizumab in patients with advanced melanoma.

802 Preservation of a Reconstructed Breast Whilst Undertaking Total Sternal Resection for Metastatic Breast Cancer with a Pedicled Latissimus Dorsi Flap and a Methyl Methacrylate Mesh Sandwich

Background

Sternal resection and reconstruction are a complex and challenging procedure that requires a multidisciplinary approach and input from both thoracic and plastic surgeons. Limited data exist on sternal resection and reconstruction for secondary breast malignancies. The goals of sternal and anterior chest wall reconstruction are to maintain chest wall integrity, rigidity, and the negative pressure necessary for respiratory and cardiac functions, protect intrathoracic contents, and restore the chest wall contour.

Case Presentation

A 40-year-old lady developed a solitary sternal metastatic lesion three years after her initial diagnosis with BRCA2 positive breast cancer. She had previously undergone left mastectomy, axillary clearance and implant reconstruction followed by right prophylactic mastectomy and implant reconstruction. She also had neoadjuvant chemotherapy and adjuvant chest wall radiotherapy. Her solitary sternal metastasis was managed with curative intent by complete sternal resection and a combined alloplastic and autologous sternal reconstruction with methyl methacrylate sandwiched between a polypropylene mesh and covered with a pedicled latissimus dorsi flap. The flap was successfully tunnelled under the previous implant-based breast reconstruction capsule. The surgical margins were clear, there were no post-operative complications and no further disease. The patient achieved good cosmetic outcomes.

Conclusions

We describe the first case of breast implant preservation whilst undertaking total sternal resection for an isolated sternal metastasise and reconstruction with a pedicle latissimus dorsi flap and methyl methacrylate mesh sandwich. We advocate combined approach with thoracic and plastic surgery, which allows a safe single stage procedure.

Modeling aerosol transmission of SARS-CoV-2 from human-exhaled particles in a hospital ward

The COVID-19 pandemic has plunged the world into uncharted territory, leaving people feeling helpless in the face of an invisible threat of unknown duration that could adversely impact the national economic growths. According to the World Health Organization (WHO), the SARS-CoV-2 spreads primarily through droplets of saliva or discharge from the mouth or nose when an infected person coughs or sneezes. However, the transmission of the SARS-CoV-2 through aerosols remains unclear. In this study, computational fluid dynamic (CFD) is used to complement the investigation of the SARS-CoV-2 transmission through aerosol. The Lagrangian particle tracking method was used to analyze the dispersion of the exhaled particles from a SARS-CoV-2-positive patient under different exhale activities and different flow rates of chilled (cooling) air supply. Air sampling of the SARS-CoV-2 patient ward was conducted for 48-h measurement intervals to collect the indoor air sample for particulate with diameter less than 2.5 μm. Then, the reverse transcription quantitative real-time polymerase chain reaction (RT-qPCR) was conducted to analyze the collected air sample. The simulation demonstrated that the aerosol transmission of the SARS-CoV-2 virus in an enclosed room (such as a hospital ward) is highly possible.

["Somatic symptom disorders" in adolescence. A systematic review of the recent literature]

OBJECTIVES

Body expression of mental disorders is common in adolescence. Only two literature reviews over the last five years have been identified about somatoform disorders in children., The present article provides a systematic review of articles in English, which concern "Somatic Symptom and Related Disorders" according to the DSM-5 (Diagnostic and Statistical Manual - 5th Edition) among adolescents.

METHODS

The article search was made on Medline, Psychinfo, Google Scholar, BiomedCentral, Central and tripdatabase (for grey literature) according to PRISMA criteria and with the items "somatoform disorders" or "somatic symptom disorders". An age filter was applied for "adolescents", and a selection was done from the last five years. All articles concerning adolescents (often associated with children) were initially included, except for articles concerning eating disorders, dysmorphic disorders or adult population. Comments, editorials, opinion or descriptive articles were also excluded. The authors then carried out an analysis of the main topics, themes and questions covered in the selected publications and presented a descriptive synthesis.

RESULTS

A total of seventy-seven publications were included in the analysis, from three hundred and seventy-two publications. First, the terms used to refer to these "somatic symptom disorders" were varied, such as "somatization", "somatic complaints/symptoms", "functional disorder", "unexplained symptoms" and "somatoform disorders". Then, studies related just to adolescents were limited: most of studies included children and adolescents in their methodologies; and some of them questioned somatic symptoms from a developmental perspective. Case reports were the most represented articles among all medical specialties, with clinical descriptions about "functional neurological symptom disorder", "factitious disorder" and "somatic symptom disorder" with a medical disease, among children and adolescents. We sometimes observed a controversial borderline between psychological and somatic disorders. Various explanatory models appeared, especially the trauma path; familial and social environment was also pointed out, with a possible peer group effect; neurocognitive theories were finally described. The literature highlights the effectiveness of psychosocial therapies (especially the cognitive-behavioral therapy) and the importance of multidisciplinary management. Finally, a few studies with a qualitative methodology are represented.

CONCLUSIONS

Only nine articles included "somatic symptom disorder" in their titles, despite a terminology valued by many authors (compared to "somatoform disorders" from the DSM-IV). The heterogeneity of terminologies, case reports and explanatory models witness a lack of connexions between medical specialties. This could explain in part the wandering of adolescents and their families in the health care system. It could also contribute to the delay before diagnosis, especially when neurological symptoms exist, and a late referral for psychiatric consultation. Further studies are needed to understand difficulties to use a clinical pathway among medical specialties, when the benefit of amultidisciplinary approach seems to be unanimous.