Tuft cells mediate commensal remodeling of the small intestinal antimicrobial landscape.

Succinate produced by the commensal protist Tritrichomonas musculis (T. mu) stimulates chemosensory tuft cells, resulting in intestinal type 2 immunity. Tuft cells express the succinate receptor SUCNR1, yet this receptor does not mediate antihelminth immunity nor alter protist colonization. Here, we report that microbial-derived succinate increases Paneth cell numbers and profoundly alters the antimicrobial peptide (AMP) landscape in the small intestine. Succinate was sufficient to drive this epithelial remodeling, but not in mice lacking tuft cell chemosensory components required to detect this metabolite. Tuft cells respond to succinate by stimulating type 2 immunity, leading to interleukin-13-mediated epithelial and AMP expression changes. Moreover, type 2 immunity decreases the total number of mucosa-associated bacteria and alters the small intestinal microbiota composition. Finally, tuft cells can detect short-term bacterial dysbiosis that leads to a spike in luminal succinate levels and modulate AMP production in response. These findings demonstrate that a single metabolite produced by commensals can markedly shift the intestinal AMP profile and suggest that tuft cells utilize SUCNR1 and succinate sensing to modulate bacterial homeostasis.

Current and future techniques for human papilloma virus (HPV) testing in oropharyngeal squamous cell carcinoma.

Despite a reduction in smoking and alcohol consumption, the incidence of oropharyngeal squamous cell carcinoma (OPSCC) is rising. This is attributed to human papilloma virus (HPV) infection and screening for HPV is now recommended in all cases of OPSCC. Despite a variety of clinically available tests and new non-invasive test strategies there is no consensus on which technique is best. This review reports on current techniques for HPV detection in OPSCC and the clinical applicability of emerging techniques. Literature searches of Medline, Embase and clinicaltrials.gov using the search terms 'head and neck neoplasms', 'squamous cell carcinoma' and 'HPV testing' were performed. 45 studies were identified and included. p16 immunohistochemistry (IHC), HPV DNA in situ hybridization (ISH) and HPV polymerase chain reaction (PCR) are the commonest tests to determine HPV status. p16 IHC and HPV DNA PCR are highly sensitive whilst HPV DNA ISH is more specific, these techniques conventionally utilize surgical biopsies. New tests using PCR to screen fine needle aspirates, saliva, brush cytology and serum for HPV are promising but have variable sensitivity and specificity. These non-invasive samples avoid the morbidity of surgical biopsies and need for tissue blocks; their clinical role in screening and surveillance remains largely untested. Further work is needed to validate these tests and define their role.

Calcium channel blocker-clarithromycin drug interaction did not increase the risk of nonvertebral fracture: a population-based study.

BACKGROUND: Calcium channel blocker (CCB) use in elderly patients lowers blood pressure and can increase the risk of falls and fractures. These drugs are metabolized by the cytochrome P450 3A4 (CYP3A4) enzyme, and blood concentrations of these drugs may rise to harmful levels when CYP3A4 activity is inhibited. Clarithromycin is an inhibitor of CYP3A4, whereas azithromycin is not. OBJECTIVE: In older patients taking a CCB, we investigated whether coprescription of clarithromycin, compared with azithromycin, was associated with a higher risk of fracture. METHODS: This was a population-level retrospective cohort study in Ontario, Canada, from 2003 to 2012 of older adults (mean age = 76 years) newly prescribed clarithromycin (n = 96 226) or azithromycin (n = 94 083) while taking a CCB (amlodipine, nifedipine, felodipine, verapamil, diltiazem). The outcome assessed within 30 days of a new coprescription was a nonvertebral fracture. RESULTS: There were no differences in measured baseline characteristics between the clarithromycin and azithromycin groups. Amlodipine was the most commonly prescribed CCB (more than 50% of patients). Coprescribing clarithromycin, versus azithromycin, was not associated with a higher 30-day risk of nonvertebral fracture (124 patients of 96 226 taking clarithromycin [0.13%] vs 98 patients of 94 083 taking azithromycin [0.10%]; odds ratio = 1.23 [95% CI = 0.94-1.60]; P = 0.134). CONCLUSIONS: Among older adults taking a CCB, concurrent use of clarithromycin, compared with azithromycin, was not associated with a statistically significantly greater 30-day risk of nonvertebral fracture.

Osteoporotic fractures in patients with untreated hyperprolactinemia vs. those taking dopamine agonists: A systematic review and meta-analysis.

OBJECTIVE: Hyperprolactinemia is associated with bone fragility. Traditionally attributed to prolactin-induced hypogonadism, recent studies have identified increased fracture rates independent of gonadal function. METHODS: We performed a systematic review to identify studies assessing fracture risk in patients with untreated hyperprolactinemia compared to those on dopamine agonists. MEDLINE, EMBASE, Cochrane, Web of Science and BIOSIS Previews databases were searched from inception to December 2013 for studies of hyperprolactinemia with fractures as an outcome. Two authors independently performed title and abstract searches, full-text searches, data abstraction, and quality assessment. A summary odds ratio (OR) was calculated using a random effects model. RESULTS: Of the 197 articles identified, 2 met inclusion criteria. Both cross-sectional studies examined cabergoline use (or non-use) in patients with prolactin-secreting adenomas, with vertebral fractures as the primary outcome. For women, vertebral fractures were identified in 46% of untreated patients, vs. 20% of patients on cabergoline (OR: 0.29, 95% CI: 0.10-0.78). For men, the results were 67% in untreated, vs. 26% in cabergoline treated patients (OR: 0.18, CI: 0.03-0.94), with no difference between gonadal and hypogonadal men (p=0.8). Combining studies gave a summary odds ratio of 0.25 (CI: 0.11-0.59), I2=0%. CONCLUSIONS: In the limited studies available, fracture prevalence was increased in patients with untreated hyperprolactinemia compared to those on treatment, independent of gonadal function. Further studies are needed to clarify if post-menopausal women, or high-risk men, with no other indication for treatment, should be on dopamine agonists to decrease fracture risk.

The three-year incidence of fracture in chronic kidney disease.

Knowing a person's fracture risk according to their kidney function, gender, and age may influence clinical management and decision-making. Using healthcare databases from Ontario, Canada, we conducted a cohort study of 679,114 adults of 40 years and over (mean age 62 years) stratified at cohort entry by estimated glomerular filtration rate ((eGFR) 60 and over, 45-59, 30-44, 15-29, and under 15 ml/min per 1.73 m(2)), gender, and age (40-65 and over 65 years). The primary outcome was the 3-year cumulative incidence of fracture (proportion of adults who fractured (hip, forearm, pelvis, or proximal humerus) at least once within 3-years of follow-up). Additional analyses examined the fracture incidence per 1000 person-years, hip fracture alone, stratification by prior fracture, stratification by eGFR and proteinuria, and 3-year cumulative incidence of falls with hospitalization. The 3-year cumulative incidence of fracture significantly increased in a graded manner in adults with a lower eGFR for both genders and both age groups. The 3-year cumulative incidence of fracture in women over 65 years of age across the 5 eGFR groups were 4.3%, 5.8%, 6.5%, 7.8%, and 9.6%, respectively. Corresponding estimates for men over 65 years were 1.6%, 2.0%, 2.7%, 3.8%, and 5.0%, respectively. Similar graded relationships were found for falls with hospitalization and additional analyses. Thus, many adults with chronic kidney disease will fall and fracture. Results can be used for prognostication and guidance of sample size requirements for fracture prevention trials.

Effect of Anticholinergic Medications on Falls, Fracture Risk, and Bone Mineral Density Over a 10-Year Period.

BACKGROUND: Many medications used in older adults have strong anticholinergic (ACH) properties, which may increase the risk of falls and fractures. Use of these medications was identified in a population-based Canadian cohort. OBJECTIVE: To identify the fall and fracture risk associated with ACH medication use. METHODS: Data collection and analysis were conducted at baseline, year 5, and year 10. Cross-sectional analyses were performed to examine associations between ACH medication use and falls. Time-dependent Cox regression was used to examine time to first nontraumatic fracture. Finally, change in bone mineral density (BMD) over 10 years was compared in ACH medication users versus nonusers. RESULTS: Strongly ACH medications were used by 618 of 7753 participants (8.0%) at study baseline, 592 (9.5%) at year 5, and 334 (7.7%) at year 10. Unadjusted ACH medication use was associated with falls at baseline (odds ratio = 1.50; 95% CI = 1.14-1.98; P = 0.004), but the association was no longer significant after covariate adjustment. Similar results occurred at years 5 and 10. ACH medication use was associated with increased incident fracture risk before (hazard ratio = 1.22; CI = 1.13-1.32; P < 0.001) but not after covariate adjustment. Mean (SD) change in femoral neck BMD T-score over 10 years, in those using ACH medications at both years 0 and 5, was -0.60 (0.63) in ACH users versus -0.49 (0.45) in nonusers (P = 0.041), but this was not significant after covariate adjustment. CONCLUSIONS: ACH medications were not found to be independently associated with an increased risk of falling, fractures, or BMD loss. Rather, factors associated with ACH medication use explained the apparent associations.

Fractures are increased and bisphosphonate use decreased in individuals with insulin-dependent diabetes: a 10 year cohort study.

BACKGROUND: Individuals with diabetes have been found previously to be at increased risk of non-traumatic fracture. However, it is unclear if these individuals are being identified and treated for osteoporosis. METHODS: 7753 Canadians over 50 years of age were followed prospectively for 10 years. 606/7753 (7.8%) of had diabetes; 98 were insulin-dependent and 508 were not. Using a cox proportional hazards model, we assessed the association between diabetes status and incident non-traumatic fracture. Using logistic regression we identified factors associated with bisphosphonate use over the 10 year period of study. RESULTS: Mean (SD) age of participants was 66.7(9.4) years and 72% were female. Those with diabetes had higher BMD T-scores at baseline, with a mean (SD) femoral neck T-Score of -0.97 (1.06), compared to -1.24 (0.99) in the general cohort. The adjusted hazard ratio (HR) for incident non-traumatic fracture in individuals with insulin-dependent diabetes over the 10 year study period was 2.50 (95% confidence interval [CI] 1.60, 3.90; p < 0.001). Despite this increased fracture rate, individuals with diabetes (insulin-dependent or non-insulin-dependent) were less likely to be on bisphosphonate therapy at any point over 10 years of prospective follow up compared to other CaMos subjects (odds ratio [OR]: 0.59; 95% CI 0.46-0.75, p < 0.001). CONCLUSIONS: Despite the increased risk of non-traumatic fracture associated with insulin-dependent diabetes, we that found individuals with diabetes are less likely to be treated with a bisphosphonate than those without diabetes. These findings point to a possible care gap in the treatment of non-traumatic fractures in individuals with diabetes in Canada.

BATF is Required for Treg Homeostasis and Stability to Prevent Autoimmune Pathology.

Regulatory T (Treg) cells are inevitable to prevent deleterious immune responses to self and commensal microorganisms. Treg function requires continuous expression of the transcription factor (TF) FOXP3 and is divided into two major subsets: resting (rTregs) and activated (aTregs). Continuous T cell receptor (TCR) signaling plays a vital role in the differentiation of aTregs from their resting state, and in their immune homeostasis. The process by which Tregs differentiate, adapt tissue specificity, and maintain stable phenotypic expression at the transcriptional level is still inconclusivei. In this work, the role of BATF is investigated, which is induced in response to TCR stimulation in naïve T cells and during aTreg differentiation. Mice lacking BATF in Tregs developed multiorgan autoimmune pathology. As a transcriptional regulator, BATF is required for Treg differentiation, homeostasis, and stabilization of FOXP3 expression in different lymphoid and non-lymphoid tissues. Epigenetically, BATF showed direct regulation of Treg-specific genes involved in differentiation, maturation, and tissue accumulation. Most importantly, FOXP3 expression and Treg stability require continuous BATF expression in Tregs, as it regulates demethylation and accessibility of the CNS2 region of the Foxp3 locus. Considering its role in Treg stability, BATF should be considered an important therapeutic target in autoimmune disease.

An unusual pigmented tonsil neoplasm presenting to Head & Neck Clinic: a case report and literature review of primary tonsillar malignant mucosal melanoma.

Primary mucosal melanoma of the tonsil is rare, with 27 reported cases. Careful diagnosis is necessary, as the tonsil is more often a site of metastatic melanoma from a cutaneous primary tumour. In this report, we present a case of primary right tonsillar mucosal melanoma with widespread metastasis in a 31-year-old man who presented with a 3-month history of enlarging neck lumps. On examination, he had cervical lymphadenopathy and a pigmented, vascular lesion of his right tonsil, which was diagnosed as melanoma following investigation. He had widespread metastases upon presentation, and is currently undergoing palliative immunotherapy. Owing to the aggressive behaviour, late presentations and lack of effective treatment to cure mucosal melanomas, they have a poor prognosis. Treatment involves wide local excision in local disease, and immunotherapy as the first-line for metastatic disease.

Functional Outcomes Following Total Laryngectomy and Pharyngolaryngectomy: A 20-Year Single Center Study.

BACKGROUND: Laryngeal cancer accounts for 1% of all cancers in men and 0.3% of all cancers in women. Pharyngolaryngectomy (TPL) and total laryngectomy (TL) are central surgical techniques in the management of advanced laryngeal malignancies but are associated with significant morbidity. In addition, optimal reconstruction following TPL remains an area of active research. METHODS: Here, we compared speech and swallowing outcomes following circumferential and partial pharyngeal resection alongside total laryngectomy in patients with laryngeal and hypolaryngeal tumors. We performed a systemic analysis of patient demographics, tumor characteristics, treatment modality, and pharyngeal reconstruction technique following TPL and TL, leveraging data collected over a 20-year period at a large tertiary referral center. RESULTS: Analyzing 155 patients the results show circumferential pharyngeal defects and prior radiotherapy have a significant impact on surgical complications. CONCLUSION: Pharyngeal resection carries a substantial risk of incurring impaired speech and swallowing in patients. Moreover, our results support poorer functional outcomes with more radical pharyngeal resections and show a clear trend toward worse swallowing outcomes in salvage surgery.

A rearrangement of the Z chromosome topology influences the sex-linked gene display in the European corn borer, Ostrinia nubilalis.

Males are homogametic (ZZ) and females are heterogametic (WZ) with respect to the sex chromosomes in many species of butterflies and moths (insect order Lepidoptera). Genes on the Z chromosome influence traits involved in larval development, environmental adaptation, and reproductive isolation. To facilitate the investigation of these traits across Lepidoptera, we developed 43 degenerate primer pairs to PCR amplify orthologs of 43 Bombyx mori Z chromosome-linked genes. Of the 34 orthologs that amplified by PCR in Ostrinia nubilalis, 6 co-segregated with the Z chromosome anchor markers kettin (ket) and lactate dehydrogenase (ldh), and produced a consensus genetic linkage map of ~89 cM in combination with 5 AFLP markers. The O. nubilalis and B. mori Z chromosomes are comparatively co-linear, although potential gene inversions alter terminal gene orders and a translocation event disrupted synteny at one chromosome end. Compared to B. mori orthologs, O. nubilalis Z chromosome-linked genes showed conservation of tissue-specific and growth-stage-specific expression, although some genes exhibited species-specific expression across developmental stages or tissues. The O. nubilalis Z chromosome linkage map provides new tools for isolating quantitative trait loci (QTL) involved in sex-linked traits that drive speciation and it exposes genome rearrangements as a possible mechanism for differential gene regulation in Lepidoptera.

A single major QTL controls expression of larval Cry1F resistance trait in Ostrinia nubilalis (Lepidoptera: Crambidae) and is independent of midgut receptor genes.

The European corn borer, Ostrinia nubilalis (Lepidoptera: Crambidae), is an introduced crop pest in North America that causes major damage to corn and reduces yield of food, feed, and biofuel materials. The Cry1F toxin from Bacillus thuringiensis (Bt) expressed in transgenic hybrid corn is highly toxic to O. nubilalis larvae and effective in minimizing feeding damage. A laboratory colony of O. nubilalis was selected for high levels of Cry1F resistance (>12,000-fold compared to susceptible larvae) and is capable of survival on transgenic hybrid corn. Genetic linkage maps with segregating AFLP markers show that the Cry1F resistance trait is controlled by a single quantitative trait locus (QTL) on linkage group 12. The map position of single nucleotide polymorphism (SNP) markers indicated that midgut Bt toxin-receptor genes, alkaline phosphatase, aminopeptidase N, and cadherin, are not linked with the Cry1F QTL. Evidence suggests that genes within this genome interval may give rise to a novel Bt toxin resistance trait for Lepidoptera that appears independent of known receptor-based mechanisms of resistance.

Clinical risk factors for fracture in diabetes: a matched cohort analysis.

The objective was to determine which individuals with diabetes are at increased risk for fracture. It is unknown whether traditional clinical risk factors (CRFs) can be used in this population to identify individuals at higher risk of fracture. Using the Manitoba Bone Density Program database, we identified 3054 diabetic women and 9151 matched nondiabetic controls. The independent association of specific CRFs with incident osteoporotic fracture risk was assessed separately in those with diabetes and in controls, with subsequent examination of the interaction between diagnosed diabetes and each CRF. Prior major fractures were more prevalent in the diabetic group compared with the nondiabetic group (16.2% vs 14.3%, p<0.001). During mean 4 yr of observation, 259 (8.5%) of diabetic women and 559 (6.5%) of nondiabetic women experienced an incident major osteoporotic fracture (unadjusted hazard ratio [HR] for diabetes 1.49 [95% confidence interval (CI): 1.28-1.72], p<0.001; adjusted HR 1.14 [95% CI: 1.10-1.18], p<0.001). There were no significant differences between the 2 groups in the HRs for incident fracture associated with any of the CRFs studied (all p-for-interaction >0.1). Diabetes is a risk factor for major fracture. The ability of traditional CRFs to predict osteoporotic fractures is not influenced by the diagnosis of diabetes.

Composite poorly differentiated mucoepidermoid carcinoma of the thyroid and follicular variant of papillary thyroid carcinoma. Report of a case and review of the literature.

Mucoepidermoid variant of thyroid carcinoma is a rare and complex disease. Securing a diagnosis and formulating an evidence-based treatment plan is challenging. A case report of a patient with the dual pathology of a composite mucoepidermoid carcinoma of the thyroid and a follicular variant of papillary thyroid carcinoma with malignant metastasis is presented in this article. We discuss the challenges in diagnosis, prognostic factors and management of this rare presentation by reviewing current literature.

Contracting Strategies for Arthroplasty-Bundles to Population Health.

Orthopedics, and especially total joint replacement (TJR), is growing in payer prominence due to large projected increases in volume. The unsustainability of the fee-for-service payment system has lead Centers for Medicare and Medicaid Services to employ new value and risk-based contracting strategies on a population health basis and on an episode of care basis, with programs such as the Bundled Payment for Care Improvement program and the Comprehensive Care for Joint Replacement program. These trends are forcing hospitals and physicians to align to improve quality and reduce costs through new structures such as Accountable Care Organizations, comanagement programs, and gainsharing. Bundled payment programs are typically used to align specialists such as orthopedic surgeons and TJR has been on the forefront of bundled payment contracting strategies. Bundled payment programs with commercial insurers can create additional opportunities, as do commercial bundled payment contracts for TJR performed on an outpatient basis. As these programs are now becoming mandatory, surgeons must understand the structural aspects of these arrangements and the levers available to optimize the likelihood of success.

Use of the self-retaining Alexis ring retractor in transoral robotic surgery.

BACKGROUND: Ring retractors, such as the Alexis® wound retractor, are simple devices used in a wide range of surgical settings to provide atraumatic exposure while protecting wound edges. METHODS: Here, we describe the application of the Alexis® to provide access during transoral robotic surgery (TORS). CONCLUSION: Its ease of application and many benefits, including maximization of intraoral space and protection of perioral soft tissues, make this device an excellent adjunct for TORS procedures.

Risk factors for fracture in adult kidney transplant recipients.

AIM: To determine the general and transplant-specific risk factors for fractures in kidney transplant recipients. METHODS: We conducted a cohort study of all adults who received a kidney-only transplant (n = 2723) in Ontario, Canada between 2002 and 2009. We used multivariable Cox proportional hazards regression to determine general and transplant-specific risk factors for major fractures (proximal humerus, forearm, hip, and clinical vertebral). The final model was established using the backward elimination strategy, selecting risk factors with a P-value ≤ 0.2 and forcing recipient age and sex into the model. We also assessed risk factors for other fracture locations (excluding major fractures, and fractures involving the skull, hands or feet). RESULTS: There were 132 major fractures in the follow-up (8.1 fractures per 1000 person-years). General risk factors associated with a greater risk of major fracture were older recipient age [adjusted hazard ratio (aHR) per 5-year increase 1.11, 95%CI: 1.03-1.19] and female sex (aHR = 1.81, 95%CI: 1.28-2.57). Transplant-specific risk factors associated with a greater risk of fracture included older donor age (5-year increase) (aHR = 1.09, 95%CI: 1.02-1.17) and end-stage renal disease (ESRD) caused by diabetes (aHR = 1.72, 95%CI: 1.09-2.72) or cystic kidney disease (aHR = 1.73, 95%CI: 1.08-2.78) (compared to glomerulonephritis as the reference cause). Risk factors across the two fracture locations were not consistent (major fracture locations vs other). Specifically, general risk factors associated with an increased risk of other fractures were diabetes and a fall with hospitalization prior to transplantation, while length of time on dialysis, and renal vascular disease and other causes of ESRD were the transplant-specific risk factors associated with a greater risk of other fractures. CONCLUSION: Both general and transplant-specific risk factors were associated with a higher risk of fractures in kidney transplant recipients. Results can be used for clinical prognostication.

Frequency of bone mineral density testing in adult kidney transplant recipients from Ontario, Canada: a population-based cohort study.

BACKGROUND: We lack consensus on the clinical value, frequency, and timing of bone mineral density (BMD) testing in kidney transplant recipients. This study sought to determine practice patterns in BMD testing across kidney transplant centres in Ontario, Canada, and to compare the frequency of testing in kidney transplant recipients to non-transplant reference groups. METHODS: Using healthcare databases from Ontario, Canada we conducted a population-based cohort study of adult kidney transplant recipients who received a transplant from 1994-2009. We used logistic regression to determine if there was a statistically significant difference across transplant centres in the decision to perform at least one BMD test after transplantation, adjusting for covariates that may influence a physician's decision to order a BMD test. We used the McNemar's test to compare the number of recipients who had at least one BMD test to non-transplant reference groups (matching on age, sex, and date of cohort entry). RESULTS: In the first 3 years after transplant, 4821 kidney transplant recipients underwent 4802 BMD tests (median 1 test per recipient, range 0 to 6 tests), costing $600,000 (2014 CAD equivalent dollars). Across the six centres, the proportion of recipients receiving at least one BMD test varied widely (ranging from 15.6 to 92.1 %; P < 0.001). Over half (58 %) of the recipients received at least one BMD test post-transplant, a value higher than two non-transplant reference groups (general population with a previous non-vertebral fracture [hip, forearm, proximal humerus], 13.8 %; general population with no previous non-vertebral fracture, 8.5 %; P value <0.001 for each of the comparisons). CONCLUSIONS: There is substantial practice variability in BMD testing after transplant. New high-quality information is needed to inform the utility, optimal timing, and frequency of BMD testing in kidney transplant recipients.

MISE EN CONTEXTE: À ce jour, il n'existe aucun consensus sur la pertinence, au plan clinique, de demander une analyse de la densité minérale osseuse (DMO) chez les receveurs d'une greffe de rein, non plus que sur la fréquence ni le moment opportun pour y soumettre les patients après leur intervention. OBJECTIFS DE L'ÉTUDE: L'étude avait pour but d'établir un schéma de pratique pour la mesure de la DMO dans plusieurs centres de transplantation rénale en Ontario, au Canada. On a également voulu comparer la fréquence de ces analyses chez les patients ayant reçu une greffe rénale par rapport à un groupe de référence constitué de patients non transplantés. CADRE ET TYPE D'ÉTUDE: Il s'agit d'une étude rétrospective par cohorte représentative de la population, qui s'est tenue dans six centres de transplantation rénale en Ontario, au Canada. PATIENTS: Il s'agit d'une cohorte de patients ayant reçu une greffe du rein entre 1994 et 2009. MESURES: Les renseignements sur la fréquence, le coût total et les variations dans le nombre d'analyses de la DMO pour une période couvrant les trois années suivant la greffe ont été compilés dans chacun des six centres. La fréquence des analyses de la DMO chez les patients greffés a été comparée à la fréquence de ces mêmes tests pratiqués chez les sujets de groupes témoins, apparentés sur les plans de l'âge, du sexe et de la date de leur admission dans la cohorte, mais n'ayant pas subi une greffe du rein. MÉTHODE: L'analyse par régression logistique a été utilisée pour établir la présence de différences significatives du point de vue statistique entre les six centres de transplantation en regard de la décision d'effectuer au moins un test de DMO à la suite d'une greffe rénale. L'analyse a tenu compte des covariables qui pouvaient influencer les médecins traitants au moment de décider de procéder ou non à un test de DMO sur leurs patients greffés. Le test McNemar a été utilisé pour comparer le nombre de patients greffés ayant été soumis à une analyse de leur DMO par rapport au groupe témoin. RÉSULTATS: À l'intérieur d'une période de trois ans suivant leur transplantation, un total de 4802 analyses de DMO ont été demandées parmi les 4821 patients greffés du rein répertoriés dans les six centres participant à l'étude. La valeur médiane se situait à un test par patient sur une échelle allant de 0 à 6 tests par patient. Le coût total évalué pour ces 4802 analyses de DMO était de 600 000 CDN en 2014. La proportion de receveurs de greffe ayant été soumis à une analyse de leur DMO a fluctué considérablement d'un centre de transplantation à l'autre, avec des pourcentages variant de 15,6 % à 92,1 % (P < 0,001). Dans l'ensemble, on a analysé la DMO de plus de la moitié (58 %) des patients greffés au moins une fois après leur intervention. Ce résultat s'est avéré plus élevé que les pourcentages mesurés dans deux des groupes témoins non transplantés (valeur de P < 0,001 pour chaque cas) : un premier groupe constitué de gens qui avaient subi une fracture non vertébrale (hanche, avant-bras ou humérus proximal) par le passé (13,8 %) et un second groupe constitué de gens de la population générale n'ayant pas subi de fractures (8,5 %). LIMITES DE L'ÉTUDE: Les renseignements concernant les médicaments d'ordonnance administrés aux participants étaient incomplets et les valeurs de DMO étaient manquantes dans plusieurs cas. De plus, le faible taux de fractures subies par les participants ne permet pas d'établir une relation entre la valeur de DMO mesurée et le risque de fractures. CONCLUSIONS: Une variabilité importante a été constatée dans la pratique d'analyses de la DMO à la suite d'une transplantation rénale. Davantage de données sont nécessaires pour discuter de la pertinence d'effectuer ce test chez les receveurs de greffe rénale, ainsi que pour établir le moment opportun et la fréquence à laquelle les y soumettre après l'intervention.

Fracture Incidence in Adult Kidney Transplant Recipients.

BACKGROUND: It remains uncertain whether kidney transplant recipients are a high-risk group for fracture. METHODS: We conducted a cohort study using Ontario, Canada health care databases to estimate the 3-, 5- and 10-year cumulative incidence of nonvertebral fracture (proximal humerus, forearm, hip) in adult kidney transplant recipients between 1994 and 2009, stratifying by sex and age (<50 versus ≥50 years) at transplant. We also assessed the 3-year cumulative incidence of all fracture locations (excluding skull, toes, and fingers) and falls, 10-year cumulative incidence of hip fracture alone, and nonvertebral fracture incidence in recipients compared to nontransplant reference groups matched on age, sex, and cohort entry year. We studied 4821 recipients (median age, 50 years). RESULTS: Among the age and sex strata, female recipients aged 50 years or older had the highest 3-year cumulative incidence of nonvertebral fracture (3.1%; 95% confidence interval [95% CI], 2.1-4.4%). Recipients had a higher 3-year cumulative incidence of nonvertebral fracture (1.6%; 95% CI, 1.3-2.0%) compared to the general population with no previous nonvertebral fracture (0.5%; 95% CI, 0.4-0.6%; P < 0.0001) and nondialysis chronic kidney disease (1.1%; 95% CI, 0.9-1.2%; P = 0.03), but a lower fracture incidence than the general population with a previous nonvertebral fracture (2.3%; 95% CI, 1.9-2.8%; P = 0.007). The 10-year cumulative incidence of hip fracture in all recipients was 1.7% (≥3% defined as high risk in clinical guidelines). CONCLUSIONS: Kidney transplant recipients may have a lower fracture risk than previously suggested in the literature. Results inform our understanding of fracture incidence after kidney transplantation and how it compares to nontransplant populations.