Lebanese Hospital Geitaoui-University Medical Center

BACKGROUND: Childhood cancer is a highly curable disease when timely diagnosis and appropriate therapy are provided. A negative impact of the coronavirus disease 2019 (COVID-19) pandemic on access to care for children with cancer is likely but has not been evaluated. METHODS: A 34-item survey focusing on barriers to pediatric oncology management during the COVID-19 pandemic was distributed to heads of pediatric oncology units within the Pediatric Oncology East and Mediterranean (POEM) collaborative group, from the Middle East, North Africa, and West Asia. Responses were collected on April 11 through 22, 2020. Corresponding rates of proven COVID-19 cases and deaths were retrieved from the World Health Organization database. RESULTS: In total, 34 centers from 19 countries participated. Almost all centers applied guidelines to optimize resource utilization and safety, including delaying off-treatment visits, rotating and reducing staff, and implementing social distancing, hand hygiene measures, and personal protective equipment use. Essential treatments, including chemotherapy, surgery, and radiation therapy, were delayed in 29% to 44% of centers, and 24% of centers restricted acceptance of new patients. Clinical care delivery was reported as negatively affected in 28% of centers. Greater than 70% of centers reported shortages in blood products, and 47% to 62% reported interruptions in surgery and radiation as well as medication shortages. However, bed availability was affected in <30% of centers, reflecting the low rates of COVID-19 hospitalizations in the corresponding countries at the time of the survey. CONCLUSIONS: Mechanisms to approach childhood cancer treatment delivery during crises need to be re-evaluated, because treatment interruptions and delays are expected to affect patient outcomes in this otherwise largely curable disease.

BACKGROUND: The Mini-Mental State Examination (MMSE) has not been validated in the Lebanese population and no normative data exist at the national level. OBJECTIVE: To evaluate the reliability and validity of an Arabic version of MMSE developed by the "Groupe de Travail sur les Démences de l'Université Saint Joseph" (A-MMSE(GTD-USJ)) and to provide normative data by gender, age, and education in adults over 55. METHODS: Study design: national cross-sectional survey. STUDY POPULATION: 1,010 literate community-dwelling Lebanese residents aged 55 and above. OUTCOMES: reproducibility, internal consistency, sensitivity, specificity, predictive values, and area under the curve of the A-MMSE(GTD-USJ) for the detection of cognitive impairment using the Clinical Dementia Rating (CDR) as the gold standard. Normative data were established from 720 healthy adults. A-MMSE(GTD-USJ) scores corresponding to the 5th, 10th, 15th, and 50th percentiles were identified according to gender, age, and education. RESULTS: Intra-rater and inter-rater test-retest score correlations were 0.89 and 0.72, respectively. Cronbach alpha coefficient for internal consistency of the A-MMSE(GTD-USJ) was 0.71. A threshold value of 23 provided a sensitivity of 80% and a specificity of 89.4%. The area under the curve was 0.92. A-MMSE(GTD-USJ) scores increased with education and decreased with age. Women had significantly lower scores than men. Normative data for A-MMSE(GTD-USJ) stratified by gender, age, and education were generated. CONCLUSION: In reference to the CDR, the A-MMSE(GTD-USJ) is a valid tool to assess cognitive status among Lebanese subjects aged 55 and above. Normative data will help clinicians in detecting cognitive impairment in this population.

An International Working Group for Treatment Optimization in MS met to recommend evidence-based therapeutic options for the management of suboptimal responses or intolerable side-effects in patients treated with disease-modifying drugs (DMDs) for multiple sclerosis (MS). Several DMDs are now available for the treatment of MS that have been shown to alter the clinical course of the disease by decreasing disease activity and delaying the progression of disability. Nevertheless, many patients continue to experience disease activity whilst on treatment, and recommendations have been made on how the success of therapy in an individual patient can be assessed. However, even after having identified criteria for a suboptimal response to current treatments, clinicians require guidance on how to improve the outcomes. This report summarizes the conclusions from a workshop at which this issue was addressed. We suggest treatment pathways for optimizing therapy for those patients with suboptimal responses to DMDs, and therapeutic options for patients with unacceptable side-effects on their current therapy.

Multiple randomized studies have shown that combination of chemotherapy and immune checkpoint inhibitors (ICIs) leads to better response rates and survival as compared to chemotherapy alone in the advanced stage of NSCLC. Data suggesting a benefit to using ICIs in the neoadjuvant therapy of patients with early stage NSCLC are emerging. Eligible subjects were treatment naïve patients with stage IB, II, and resectable IIIA NSCLC. Patients received three cycles of neoadjuvant chemotherapy with four doses of avelumab every 2 weeks. Patients with squamous cell cancer received cisplatin or carboplatin on day 1 and gemcitabine on days 1 and 8 of each cycle of chemotherapy. Patients with nonsquamous histology received cisplatin or carboplatin with pemetrexed on day 1 of each cycle. Patients then proceeded to their planned surgery. Out of 15 patients accrued as part of stage 1 of the study, four had a radiologic response (1 complete response), lower than the minimum of six responses needed to continue to phase 2 of the study. The study was therefore terminated. Majority had adenocarcinoma histology and stage IIIA disease. The treatment was well tolerated with no unexpected side effects. Four patients (26.7%) had grade III/IV CTCAE toxicity. This study confirms that the preoperative administration of chemotherapy and avelumab is safe. There was no indication of increased surgical complications. The benefit of adding immunotherapy to chemotherapy did not appear to enhance the overall response rate of patients in the neoadjuvant setting in patients with resectable NSCLC because this study failed to meet its primary endpoint.

OBJECTIVES: The acquisition of carbapenemases by Acinetobacter baumannii is reported increasingly worldwide, but data from Lebanon are limited. The aims of this study were to evaluate the prevalence of imipenem-resistant A. baumannii in Lebanon, identify resistance determinants, and detect clonal relatedness. METHODS: Imipenem-resistant A. baumannii were collected from nine Lebanese hospitals during 2012. Antimicrobial susceptibility, the cloxacillin effect, and ethylenediaminetetraacetic acid (EDTA) synergy were determined. Genes encoding carbapenemases and insertion sequence ISAba1 were screened via PCR sequencing. ISAba1 position relative to genes encoding Acinetobacter-derived cephalosporinases (ADCs) and OXA-23 was studied by PCR mapping. Clonal linkage was examined by enterobacterial repetitive intergenic consensus PCR (ERIC-PCR). RESULTS: Out of 724 A. baumannii isolated in 2012, 638 (88%) were imipenem-resistant. Of these, 142 were analyzed. Clavulanic acid-imipenem synergy suggested carbapenem-hydrolyzing extended-spectrum β-lactamase. A positive cloxacillin test indicated ADCs, while EDTA detection strips were negative. Genotyping indicated that 90% of isolates co-harbored blaOXA-23 and blaGES-11. The remaining strains had blaOXA-23, blaOXA-24, blaGES-11, or blaOXA-24 with blaGES-11. ISAba1 was located upstream of blaADC and blaOXA-23 in 97% and 100% of isolates, respectively. ERIC-PCR fingerprinting revealed 18 pulsotypes spread via horizontal gene transfer and clonal dissemination. CONCLUSION: This survey established baseline evidence of OXA-23 and GES-11-producing A. baumannii in Lebanon, indicating the need for further surveillance.

Background: Timely detection of disease outbreaks is critical in public health. Artificial Intelligence (AI) can identify patterns in data that signal the onset of epidemics and pandemics. This scoping review examines the effectiveness of AI in epidemic and pandemic early warning systems (EWS). Objective: To assess the capability of AI-based systems in predicting epidemics and pandemics and to identify challenges and strategies for improvement. Methods: A systematic scoping review was conducted. The review included studies from the last 5 years, focusing on AI and machine learning applications in EWS. After screening 1087 articles, 33 were selected for thematic analysis. Results: The review found that AI-based EWS have been effectively implemented in various contexts, using a range of algorithms. Key challenges identified include data quality, model explainability, bias, data volume, velocity, variety, availability, and granularity. Strategies for mitigating AI bias and improving system adaptability were also discussed. Conclusion: AI has shown promise in enhancing the speed and accuracy of epidemic detection. However, challenges related to data quality, bias, and model transparency need to be addressed to improve the reliability and generalizability of AI-based EWS. Continuous monitoring and improvement, as well as incorporating social and environmental data, are essential for future development.

BACKGROUND: Clinical and molecular data on the occurrence and frequency of inherited neuromuscular disorders (NMD) in the Lebanese population is scarce. OBJECTIVE: This study aims to provide a retrospective overview of hereditary NMDs based on our clinical consultations in Lebanon. METHODS: Clinical and molecular data of patients referred to a multi-disciplinary consultation for neuromuscular disorders over a 20-year period (1999-2019) was reviewed. RESULTS: A total of 506 patients were diagnosed with 62 different disorders encompassing 10 classes of NMDs. 103 variants in 49 genes were identified. In this cohort, 81.4% of patients were diagnosed with motor neuron diseases and muscular dystrophies, with almost half of these described with spinal muscular atrophy (SMA) (40.3% of patients). We estimate a high SMA incidence of 1 in 7,500 births in Lebanon. Duchenne and Becker muscular dystrophy were the second most frequently diagnosed NMDs (17% of patients). These disorders were associated with the highest number of variants (39) identified in this study. A highly heterogeneous presentation of Limb Girdle Muscular Dystrophy and Charcot-Marie-Tooth disease was notably identified. The least common disorders (5.5% of patients) involved congenital, metabolic, and mitochondrial myopathies, congenital myasthenic syndromes, and myotonic dystrophies. A review of the literature for selected NMDs in Lebanon is provided. CONCLUSIONS: Our study indicates a high prevalence and underreporting of heterogeneous forms of NMDs in Lebanon- a major challenge with many novel NMD treatments in the pipeline. This report calls for a regional NMD patient registry.

Distal hereditary motor neuropathies (dHMNs) are a heterogeneous group of diseases, resembling Charcot-Marie-Tooth syndromes, but characterized by an exclusive involvement of the motor part of the peripheral nervous system. Here, we describe two new compound heterozygous mutations in VRK1, the vaccinia-related kinase 1 gene, in two siblings from a Lebanese family, affected with dHMN associated with upper motor neurons (MNs) signs. The mutations lead to severely reduced levels of VRK1 by impairing its stability, and to a shift of nuclear VRK1 to cytoplasm. Depletion of VRK1 from the nucleus alters the dynamics of coilin, a phosphorylation target of VRK1, by reducing its stability through increased proteasomal degradation. In human-induced pluripotent stem cell-derived MNs from patients, we demonstrate that this drop in VRK1 levels leads to Cajal bodies (CBs) disassembly and to defects in neurite outgrowth and branching. Mutations in VRK1 have been previously reported in several neurological diseases affecting lower or both upper and lower MNs. Here, we describe a new phenotype linked to VRK1 mutations, presenting as a classical slowly progressive motor neuropathy, beginning in the second decade of life, with associated upper MN signs. We provide, for the first time, evidence for a role of VRK1 in regulating CB assembly in MNs. The observed MN defects are consistent with a length dependent axonopathy affecting lower and upper MNs, and we propose that diseases due to mutations in VRK1 should be grouped under a unique entity named `VRK1-related motor neuron disease'.

The majority of disease-modifying drugs (DMDs) available for the management of active relapsing-remitting multiple sclerosis (RMS) depend on continuous drug intake for maintained efficacy, with escalation to a more active drug when an unacceptable level of disease activity returns. Among continuously applied regimens, interferons and glatiramer acetate act as immunomodulators, while dimethyl fumarate, fingolimod, ocrelizumab, natalizumab and teriflunomide are associated with continuous immunosuppression. By contrast, immune reconstitution therapy (IRT) provides efficacy that outlasts a short course of treatment. Autologous hemopoietic stem cell transplantation is perhaps the classic example of IRT, but this invasive and intensive therapy has challenging side-effects. A short treatment course of a pharmacologic agent hypothesized to act as an IRT, such as Cladribine Tablets 3.5 mg/kg or alemtuzumab, can provide long-term suppression of MS disease activity, without need for continuous treatment (the anti-CD20 mechanism of ocrelizumab has the potential to act as an IRT, but is administered continuously, at 6-monthly intervals). Cladribine Tablets 3.5 mg/kg shows some selectivity in targeting adaptive immunity with a lesser effect on innate immunity. The introduction of IRT-like disease-modifying drugs (DMDs) challenges the traditional maintenance/escalation mode of treatment and raises new questions about how disease activity is measured. In this review, we consider a modern classification of DMDs for MS and its implications for the care of patients in the IRT era.

OBJECTIVE: To assess the perioperative and financial outcomes of flexible ureteroscopic lithotripsy with holmium laser for upper tract calculi in 44 patients. MATERIALS AND METHODS: Between February 2004 and September 2006, 44 patients treated for upper tract stone with flexible ureteroscopic lithotripsy were evaluated. Renal stones were associated with collecting system obstruction in 15 (34%) patients, failed extracorporeal shock-wave lithotripsy (SWL) occurred in 14 (32%) patients, unilateral multiple stones in 18 (41%) patients, and multiple bilateral stones in 3 (7%). In 29 (66%) patients, the stone was located in the inferior calyx. Perioperative and financial outcomes were also evaluated. RESULTS: 50 procedures were performed in 44 patients. The mean stone burden on preoperative CT scan was 11.5 +/- 5.8 mm. The mean operative time was 61.3 +/- 29.4 min. The stone free rate was 93.1% after one procedure and 97.7% after a second procedure, with overall complication rate of 8%. Therapeutic success occurred in 92% and 93% of patients with lower pole stones and SWL failure, respectively. Treatment failure of a single session was associated with presence of a stone size larger than 15 mm (p = 0.007), but not associated with inferior calyx location (p = 0.09). Surgical disposables were responsible for 78% of overall costs. CONCLUSION: Flexible ureteroscopy using holmium laser is a safe and effective option for the treatment of upper urinary tract calculi. In addition, it can be considered an attractive option as salvage therapy after SWL failure or kidney calculi associated with ureteral stones. Stone size larger than 15 mm is associated with single session treatment failure.

BACKGROUND: According to the Catalogue of Transmission Genetics in Arabs, less than half of diseases reported in Lebanese patients are mapped. In the recent years, Next Generation Sequencing (NGS) techniques have significantly improved clinical diagnosis, compared to traditional sequencing methods. METHODS: A total of 213 analyses by NGS (167 by whole exome sequencing (WES) and 46 by multigene panels tests) were performed on pediatric patients across different regions of Lebanon over a period of two years (December 2015-December 2017). RESULTS: Neurological disorders were the most frequent referral demand for both WES and gene panels (122/213). Pathogenic, likely pathogenic, or variants of unknown significance were identified in 69.5% of the WES and panel patients combined. Over half of the patients with such variants had an autosomal recessive disorder. A definite molecular diagnosis (pathogenic or likely pathogenic variants) was achieved in 34.1% and 47.8% of the patients studied by WES and the multigene panels, respectively. Thirty-three novel variants were found in the cases that were molecularly solved; 26 of these being identified by WES and seven by the multigene panels. In three consanguineous families, autosomal recessive inheritance of genes previously reported as showing dominant inheritance patterns were found. Biallelism was found in six cases, digenism in four cases, and one case was trigenic. CONCLUSION: Our study thus suggests that NGS tools are valuable for an improved clinical diagnosis, and highlights that the increased adoption of such techniques will significantly further improve our understanding of the genetic basis of inherited diseases in Lebanon.

Obesity is a major health problem, because of its relationship with serious medical illnesses and significant economic consequences. This article explores various factors and variables affecting the prevalence of obesity in Lebanon, to focus public health initiatives and medical interventions in the management of obesity. This study interviewed 593 subjects, of more than 20 years, from all governorates of Lebanon. The interview covered personal and demographic data, awareness, knowledge, attitude and practices towards obesity including diet and physical activity. Males’ and females’ percentages were 51.6% and 48.4%, respectively, and a young population profile was with 52.8% less than 40 years of age. The BMI index showed that 52.77% were obese with 70.6% males and 34.27% females. The great majority were educated. TV was the most used media outlet, 79.61% watching daily between 1 - 4 hours. Obesity was considered as the most important health problem by 27.6% and ranking the 5th after cancer, cardiovascular, smoking and HIV/AIDS. About two thirds considered it a risk factor for hypertension and type 2 diabetes mellitus and 80.27% for cardiovascular diseases. Interventions should include changes in diet habits whereby, approximately one third (33.5%) drink carbonated beverages on a daily basis and 50.76% eat fast food, with a lack of awareness about daily calories intake by 75.38%. About half of the population (56.32%) walks daily for 20 minutes. Most people favored behavioral and lifestyle modifications in management rather than medications and surgery (67.79%). This study provides baseline data regarding several aspects of an obesogenic environment, a major risk factor for several diseases including hypertension, diabetes and other non-communicable diseases. After describing the factors and variables affecting the prevalence of obesity, some suggestions for appropriate interventions are included, with the hope of reducing the health burden of obesity in Lebanon.

In musculoskeletal imaging, CT is used in a wide range of indications, either alone or in a synergistic approach with MRI. While MRI is the preferred modality for the assessment of soft tissues and bone marrow, CT excels in the imaging of high-contrast structures, such as mineralized tissue. Additionally, the introduction of dual-energy CT in clinical practice two decades ago opened the door for spectral imaging applications. Recently, the advent of photon-counting detectors (PCDs) has further advanced the potential of CT, at least in theory. Compared to conventional energy-integrating detectors (EIDs), PCDs provide superior spatial resolution, reduced noise, and intrinsic spectral imaging capabilities. This review briefly describes the technical advantages of PCDs. For each technical feature, the corresponding applications in musculoskeletal imaging will be discussed, including high-spatial resolution imaging for the assessment of bone and crystal deposits, low-dose applications such as whole-body CT, as well as spectral imaging applications including the characterization of crystal deposits and imaging of metal hardware. Finally, we will highlight the potential of PCD-CT in emerging applications, underscoring the need for further preclinical and clinical validation to unleash its full clinical potential.

Stroke is a major social and health problem posing heavy burden on national economies. We provided detailed financial data on the direct in-hospital cost of acute stroke care in Lebanon and evaluated its drivers. This was an observational, quantitative, prospective, multicenter, incidence-based, bottom-up cost-of-illness study. Medical and billing records of stroke patients admitted to 8 hospitals in Beirut over 1 year were analyzed. Direct medical costs were calculated, and cost drivers were assessed using a multivariable linear regression analysis. In total, 203 stroke patients were included (male: 58%; mean age: 68.8 ± 12.9 years). The direct in-hospital cost for all cases was US$1 413 069 for 2626 days (US$538 per in-hospital day). The average in-hospital cost per stroke patient was US$6961 ± 15 663. Hemorrhagic strokes were the most costly, transient ischemic attack being the least costly. Cost drivers were hospital length of stay, intensive care unit length of stay, type of stroke, stroke severity, modified Rankin Scale, third party payer, surgery, and infectious complications. Direct medical cost of acute stroke care represents high financial burden to Lebanese health system. Development of targeted public health policies and primary prevention activities need to take priority to minimize stroke admission in future and to contain this cost.

Chordomas are the most common sacrococcygeal tumors in adults. They have a high recurrence rate, are locally aggressive, and are resistant to radiation therapy. Radio frequency is a relatively new therapeutic technique, used primarily in the treatment of liver tumors; however, its application has widened to include other neoplasms. We report its use in the palliative treatment of chordomas in two patients for debulking and control of pain, with good results and low morbidity.

PURPOSE: To describe the 5-year experience of a multidisciplinary limb salvage program for children and adolescents with malignant bone tumors in Lebanon. PATIENTS AND METHODS: Between January 2002 to February 2007, 30 children and adolescents (2 with Ewing sarcoma and 28 with osteosarcoma) underwent Limb Salvage Surgeries (LSS) at the American University of Beirut Medical Center after partnering with the multidisciplinary team at St. Judes Children's Research Hospital (SJCRH). Procedures performed included 12 Repiphysis, noninvasively expandable, prostheses inserted in skeletally immature children, 15 modular prostheses, 2 allografts and 1 rotationplasty. All patients received pre- and postoperative chemotherapy. RESULTS: With a mean follow-up of 31 months, 20 patients are now off therapy, 4 died, and 6 are receiving chemotherapy (3 due to pulmonary recurrence). Complications of surgery included infections in three cases, failure of the expansion mechanism in two, femoral stem fracture in one, prostheses femoral stem loosening in one and wound dehiscence in one. Lengthening of Repiphysis prostheses was achieved by subjecting the limb to an electromagnetic field that would allow controlled release of the Repiphysis expansion mechanism. Ten patients underwent a total of 42 lengthening procedures with an average of 9 mm lengthened per procedure (range 2-15 mm). All patients have good function of the affected limb. CONCLUSION: Our LSS results are comparable to those reported in the literature. Collaboration with SJCRH and fund raising were critical to the program's success. This endeavor could serve as a model for establishing LSS programs in developing countries.

In all the major medical centers throughout the Middle East, there is a functioning pediatric hematology oncology department. In almost all countries, opioids such as morphine, oxycodone, and fentanyl are available. Pediatric palliative care services are still in their infancy and await further recognition and development. Unfortunately, there are still countries in the Middle East where children with cancer are diagnosed when the disease is already at stage III or IV, when the only option left is palliation. To decrease the incidence of late presentation, more effort is needed concerning public awareness, and concomitantly, an urgent need to develop hospital-based and community-based palliative and supportive care services. The initial step in this direction would involve more training of health care providers: Pediatricians, Pediatric Oncologists, Oncology Nurses, and Social Workers with updated pharmacological and nonpharmacological modalities of treatment.

AIM: To calculate the prevalence of human leukocyte antigen (HLA)-B27 in axial spondyloarthritis patients (axSpA) compared to blood donors (BD) in Lebanon, to identify the clinical and radiological findings associated with HLA-B27 and to estimate the proportion of patients fulfilling the clinical arm of the Assessment of the Spondyloarthritis International Association (ASAS) criteria. METHOD: Consecutive Lebanese adult axSpA patients fulfilling the ASAS classification criteria were included from 12 rheumatology clinics across Lebanon. BD served as controls. A binary logistic regression was used to study the association between HLA-B27 and the disease features. RESULTS: A total of 247 individuals were included (141 axSpA patients and 106 BD). The prevalence of HLA-B27 was 3.8% in BD and 41.1% in axSpA. Overall, 39.7% of the axSpA patients fulfilled the clinical arm of the ASAS classification criteria. Sensitivity of HLA-B27 for axSpA was 41.1%, specificity was 96.2%, positive predictive value was 93.6%, and negative predictive value was 55.13%. Positive likelihood ratio (LR) was 10.9 and negative LR was 1.63. We found a positive association of HLA-B27 with family history of SpA and psoriasis. CONCLUSION: Our study confirmed a low prevalence of HLA-B27 in axSpA patients and BD in this Lebanese population, However, we found a high specificity and positive LR, as well as the same number of axSpA patients fulfilling the clinical arm of the ASAS criteria as in European studies. HLA-B27 is therefore valuable for identification of axSpA in Lebanese patients despite the overall low prevalence in this population. Our results may guide future evaluations the role of HLA-B27 in planning local referral strategies.

BACKGROUND: Our aim was to examine whether the length of stay, hospital charges and in-hospital mortality attributable to healthcare- and community-associated infections due to antimicrobial-resistant bacteria were higher compared with those due to susceptible bacteria in the Lebanese healthcare settings using different methodology of analysis from the payer perspective . METHODS: We performed a multi-centre prospective cohort study in ten hospitals across Lebanon. The sample size consisted of 1289 patients with documented healthcare-associated infection (HAI) or community-associated infection (CAI). We conducted three separate analysis to adjust for confounders and time-dependent bias: (1) Post-HAIs in which we included the excess LOS and hospital charges incurred after infection and (2) Matched cohort, in which we matched the patients based on propensity score estimates (3) The conventional method, in which we considered the entire hospital stay and allocated charges attributable to CAI. The linear regression models accounted for multiple confounders. RESULTS: HAIs and CAIs with resistant versus susceptible bacteria were associated with a significant excess length of hospital stay (2.69 days [95% CI,1.5-3.9]; p < 0.001) and (2.2 days [95% CI,1.2-3.3]; p < 0.001) and resulted in additional hospital charges ($1807 [95% CI, 1046-2569]; p < 0.001) and ($889 [95% CI, 378-1400]; p = 0.001) respectively. Compared with the post-HAIs analysis, the matched cohort method showed a reduction by 26 and 13% in hospital charges and LOS estimates respectively. Infections with resistant bacteria did not decrease the time to in-hospital mortality, for both healthcare- or community-associated infections. Resistant cases in the post-HAIs analysis showed a significantly higher risk of in-hospital mortality (odds ratio, 0.517 [95% CI, 0.327-0.820]; p = 0.05). CONCLUSION: This is the first nationwide study that quantifies the healthcare costs of antimicrobial resistance in Lebanon. For cases with HAIs, matched cohort analysis showed more conservative estimates compared with post-HAIs method. The differences in estimates highlight the need for a unified methodology to estimate the burden of antimicrobial resistance in order to accurately advise health policy makers and prioritize resources expenditure.

Conventional magnetic resonance imaging (MRI) remains the modality of choice to image bone marrow. However, the last few decades have witnessed the emergence and development of novel MRI techniques, such as chemical shift imaging, diffusion-weighted imaging, dynamic contrast-enhanced MRI, and whole-body MRI, as well as spectral computed tomography and nuclear medicine techniques. We summarize the technical bases behind these methods, in relation to the common physiologic and pathologic processes involving the bone marrow. We present the strengths and limitations of these imaging methods and consider their added value compared with conventional imaging in assessing non-neoplastic disorders like septic, rheumatologic, traumatic, and metabolic conditions. The potential usefulness of these methods to differentiate between benign and malignant bone marrow lesions is discussed. Finally, we consider the limitations hampering a more widespread use of these techniques in clinical practice.