Demodex: a skin resident in man and his best friend

Demodex mites are microscopic arachnids found in the normal skin of many mammals. In humans, it is well established that Demodex mite density is higher in patients with the skin condition rosacea, and treatment with acaricidal agents is effective in resolving symptoms. However, pathophysiology of rosacea is complex and multifactorial. In dogs, demodicosis is a significant veterinary issue, particularly the generalized form of the disease which can be fatal if untreated. In each species, clinical and molecular studies have shown that the host’s immunological interactions with Demodex mites are an important, but not fully understood, aspect of how Demodex can live in the skin either as a harmless commensal organism or as a pathogenic agent. This review outlines the role of Demodex mites in humans and dogs, considering morphology, prevalence, symptoms, diagnosis, histology treatment and pathogenesis.     

The Effect of Homelessness on Patient Wait Times in the Emergency Department

BackgroundProlonged emergency department (ED) wait times could potentially lead to increased morbidity and mortality. While previous work has demonstrated disparities in wait times associated with race, information about the relationship between experiencing homelessness and ED wait times is lacking.ObjectivesThe purpose of this study was to explore the relationship between residence status (undomiciled vs. domiciled) and ED wait times. We hypothesized that being undomiciled would be associated with longer wait times.MethodsWe obtained data from the National Hospital Ambulatory Medical Care Survey from 2014 to 2017. We compared wait times in each triage category using t tests. We used multivariate linear regression to explore associations between residence status and wait times while controlling for other patient- and hospital-level variables.ResultsOn average, undomiciled patients experienced significantly longer mean ED wait times than domiciled patients (53.4 vs. 38.9 min; p < 0.0001). In the multivariate model, undomiciled patients experienced significantly different wait times by 15.5 min (p = 0.0002). Undomiciled patients experienced increasingly longer waits vs. domiciled patients for the emergent and urgent triage categories (+33.5 min, p < 0.0001, and +22.7 min, p < 0.0001, respectively).ConclusionsUndomiciled patients experience longer ED wait times when compared with domiciled patients. This disparity is not explained by undomiciled patients seeking care in the ED for minor illness, because the disparity is more pronounced for urgent and emergent triage categories.     

FGF13 promotes metastasis of triple-negative breast cancer

Triple-negative breast cancer (TNBC) represents 10–20% of all human ductal adenocarcinomas and has a poor prognosis relative to other subtypes, due to the high propensity to develop distant metastases. Hence, new molecular targets for therapeutic intervention are needed for TNBC. We recently conducted a rigorous phenotypic and genomic characterization of four isogenic populations of MDA-MB-231 human triple-negative breast cancer cells that possess a range of intrinsic spontaneous metastatic capacities in vivo, ranging from nonmetastatic (MDA-MB-231_ATCC) to highly metastatic to lung, liver, spleen and spine (MDA-MB-231_HM). Gene expression profiling of primary tumours by RNA-Seq identified the fibroblast growth factor homologous factor, FGF13, as highly upregulated in aggressively metastatic MDA-MB-231_HM tumours. Clinically, higher FGF13 mRNA expression was associated with significantly worse relapse free survival in both luminal A and basal-like human breast cancers but was not associated with other clinical variables and was not upregulated in primary tumours relative to normal mammary gland. Stable FGF13 depletion restricted in vitro colony forming ability in MDA-MB-231_HM TNBC cells but not in oestrogen receptor (ER)-positive MCF-7 or MDA-MB-361 cells. However, despite augmenting MDA-MB-231_HM cell migration and invasion in vitro, FGF13 suppression almost completely blocked the spontaneous metastasis of MDA-MB-231_HM orthotopic xenografts to both lung and liver while having negligible impact on primary tumour growth. Together, these data indicate that FGF13 may represent a therapeutic target for blocking metastatic outgrowth of certain TNBCs. Further evaluation of the roles of individual FGF13 protein isoforms in progression of the different subtypes of breast cancer is warranted.     

OK,Boomer, MD: The Rights of Aging Physicians and the Health of Our Communities

How do we balance the rights of aging physicians against the right of the public to competent health care? This version of a classic public health ethics dilemma is here now and likely to increase as the population ages. Peer review has long been the standard mechanism for assessing physician competence, but it is subjective and too easily subverted. New options are needed, both in medicine and throughout the professions, but they are challenging to implement. Physicians have an ethical obligation to protect the health of the public by acknowledging, assessing, and addressing the cognitive effects of aging on medical competence.     

Transplantation of viral-positive hepatitis C-positive kidneys into uninfected recipients offers an opportunity to increase organ access

The advent of direct-acting antivirals (DAAs) has provided the impetus to transplant kidneys from hepatitis C virus-positive donors into uninfected recipients (D+/R−). Thirty D+/R− patients received DAA treatment. Sustained virologic response (SVR12) was defined as an undetectable viral load in 12 weeks after treatment. An age-matched cohort of uninfected donor and recipient pairs (D−/R−) transplanted during same time period was used for comparison. The median day of viral detection was postoperative day (POD) 2. The detection of viremia in D+/R− patients was 100%. The initial median viral load was 531 copies/μL (range: 10-1 × 10⁸ copies/μL) with a median peak viral load of 3.4 × 10⁵ copies/μL (range: 804-1.0 × 10⁸ copies/μL). DAAs were initiated on median POD 9 (range: 5-41 days). All 30 patients had confirmed SVR12. During a median follow-up of 10 months, patient and graft survival was 100%, and acute rejection was 6.6% with no major adverse events related to DAA treatment. Delayed graft function was significantly decreased in D+/R− patients as compared to the age-matched cohort (27% vs 60%; P = .01). D+/R− transplantation offers patients an alternative strategy to increase access.     

An unusual case of cutaneous Waldenström macroglobulinemia with the MYD88 L265P mutation

Waldenström macroglobulinemia is a lymphoplasmacytic lymphoma with bone marrow involvement and a monoclonal IgM gammopathy. Infiltration of the skin by neoplastic cells is very rare, and it can be difficult to distinguish from marginal zone lymphoma. The MYD88 L265P mutation is strongly associated with Waldenström macroglobulinemia, and it may be helpful in differentiating the two disorders, although the presence of this mutation is not specific, and other factors must be considered when making the final diagnosis. We present a diagnostically challenging case of cutaneous Waldenström macroglobulinemia in which the MYD88 L265P mutation was identified in the skin but not in the bone marrow, due to a low tumor burden.