Next-generation phenotyping: introducing phecodeX for enhanced discovery research in medical phenomics.

MOTIVATION: Phecodes are widely used and easily adapted phenotypes based on International Classification of Diseases codes. The current version of phecodes (v1.2) was designed primarily to study common/complex diseases diagnosed in adults; however, there are numerous limitations in the codes and their structure. RESULTS: Here, we present phecodeX, an expanded version of phecodes with a revised structure and 1,761 new codes. PhecodeX adds granularity to phenotypes in key disease domains that are under-represented in the current phecode structure-including infectious disease, pregnancy, congenital anomalies, and neonatology-and is a more robust representation of the medical phenome for global use in discovery research. AVAILABILITY AND IMPLEMENTATION: phecodeX is available at https://github.com/PheWAS/phecodeX.

Comparison of late-onset and non-late-onset systemic lupus erythematosus individuals in a real-world electronic health record cohort.

Objective: Late-onset systemic lupus erythematosus (LO-SLE) is defined as SLE diagnosed at age 50 years or later. Current studies on LO-SLE are small and have conflicting results.Methods: Using a large, electronic health record (EHR)-based cohort of SLE individuals, we compared demographics, disease characteristics, SLE-specific antibodies, and medication prescribing practices in LO (n = 123) vs. NLO-SLE (n = 402) individuals.Results: The median age (interquartile range) at SLE diagnosis was 60 (56-67) years for LO-SLE and 28 (20-38) years for NLO-SLE. Both groups were predominantly female (85% vs. 91%, p = 0.10). LO-SLE individuals were more likely to be White than NLO-SLE individuals (74% vs. 60%, p = 0.005) and less likely to have positive dsDNA (39% vs. 58%, p = 0.001) and RNP (17% vs. 32%, p = 0.02) with no differences in Smith, SSA, and SSB. Autoantibody positivity declined with increasing age at SLE diagnosis. LO-SLE individuals were less likely to develop SLE nephritis (9% vs. 29%, p < 0.001) and less likely to be prescribed multiple classes of SLE medications including antimalarials (90% vs. 95%, p = 0.04), azathioprine (17% vs. 31%, p = 0.002), mycophenolate mofetil (12% vs. 38%, p < 0.001), and belimumab (2% vs. 8%, p = 0.02).Conclusion: LO-SLE individuals may be less likely to fit an expected course for SLE with less frequent positive autoantibodies at diagnosis and lower rates of nephritis, even after adjusting for race. Understanding how age impacts SLE disease presentation could help reduce diagnostic delays in SLE.

A Report on the Safety of Acitretin Use in Renal Failure Patients on Hemodialysis.

Acitretin, commonly used for severe psoriasis and keratinocyte carcinoma chemoprevention in high-risk patients, is contraindicated in patients with end stage renal disease on hemodialysis. However, these patients often lack medication choices and in certain clinical scenarios, the benefits of acitretin may outweigh the potential risks. We identified 24 end stage renal disease patients on HD taking acitretin from Duke and Vanderbilt University Medical Centers. While adverse effects were common, patients did not frequently discontinue the medication due to them. We also found no association between acitretin with hospital admissions or mortality. We lastly found statistically significant increases in ALP and total bilirubin when on acitretin and dialysis compared to baseline. However, there was no dose-dependency or temporal association with acitretin or hemodialysis initiation. Based off these preliminary findings, we find that acitretin may safely be used in patients receiving HD with close monitoring of ALP and bilirubin.

Genetic Inhibition of APOL1 Pore-Forming Function Prevents APOL1-Mediated Kidney Disease.

SIGNIFICANCE STATEMENT: African Americans are at increased risk of CKD in part due to high-risk (HR) variants in the apolipoprotein L1 ( APOL1 ) gene, termed G1/G2. A different APOL1 variant, p.N264K , reduced the risk of CKD and ESKD among carriers of APOL1 HR variants to levels comparable with individuals with APOL1 low-risk variants in an analysis of 121,492 participants of African ancestry from the Million Veteran Program (MVP). Functional genetic studies in cell models showed that APOL1 p.N264K blocked APOL1 pore-forming function and ion channel conduction and reduced toxicity of APOL1 HR mutations. Pharmacologic inhibitors that mimic this mutation blocking APOL1 -mediated pore formation may be able to prevent and/or treat APOL1 -associated kidney disease. BACKGROUND: African Americans are at increased risk for nondiabetic CKD in part due to HR variants in the APOL1 gene. METHODS: We tested whether a different APOL1 variant, p.N264K , modified the association between APOL1 HR genotypes (two copies of G1/G2) and CKD in a cross-sectional analysis of 121,492 participants of African ancestry from the MVP. We replicated our findings in the Vanderbilt University Biobank ( n =14,386) and National Institutes of Health All of Us ( n =14,704). Primary outcome was CKD and secondary outcome was ESKD among nondiabetic patients. Primary analysis compared APOL1 HR genotypes with and without p.N264K . Secondary analyses included APOL1 low-risk genotypes and tested for interaction. In MVP, we performed sequential logistic regression models adjusting for demographics, comorbidities, medications, and ten principal components of ancestry. Functional genomic studies expressed APOL1 HR variants with and without APOL1 p.N264K in cell models. RESULTS: In the MVP cohort, 15,604 (12.8%) had two APOL1 HR variants, of which 582 (0.5%) also had APOL1 p.N264K . In MVP, 18,831 (15%) had CKD, 4177 (3%) had ESKD, and 34% had diabetes. MVP APOL1 HR, without p.N264K , was associated with increased odds of CKD (odds ratio [OR], 1.72; 95% confidence interval [CI], 1.60 to 1.85) and ESKD (OR, 3.94; 95% CI, 3.52 to 4.41). In MVP, APOL1 p.N264K mitigated the renal risk of APOL1 HR, in CKD (OR, 0.43; 95% CI, 0.28 to 0.65) and ESKD (OR, 0.19; CI 0.07 to 0.51). In the replication cohorts meta-analysis, APOL1 p.N264K mitigated the renal risk of APOL1 HR in CKD (OR, 0.40; 95% CI, 0.18 to 0.92) and ESKD (OR, 0.19; 95% CI, 0.05 to 0.79). In the mechanistic studies, APOL1 p.N264K blocked APOL1 pore-forming function and ion channel conduction and reduced toxicity of APOL1 HR variants. CONCLUSIONS: APOL1 p.N264K is associated with reduced risk of CKD and ESKD among carriers of APOL1 HR to levels comparable with individuals with APOL1 low-risk genotypes.

Recent Advances in Melanoma Diagnosis and Prognosis Using Machine Learning Methods.

PURPOSE OF REVIEW: The purpose was to summarize the current role and state of artificial intelligence and machine learning in the diagnosis and management of melanoma. RECENT FINDINGS: Deep learning algorithms can identify melanoma from clinical, dermoscopic, and whole slide pathology images with increasing accuracy. Efforts to provide more granular annotation to datasets and to identify new predictors are ongoing. There have been many incremental advances in both melanoma diagnostics and prognostic tools using artificial intelligence and machine learning. Higher quality input data will further improve these models' capabilities.

Novel Biomaterial Containing Gelatin, Manuka Honey, and Hydroxyapatite Enhanced Secondary Intention Healing Versus Standard Secondary Intention Healing in Mohs Surgical Defects on the Head and Distal Lower Extremities-A Randomized Controlled Trial: Pilot Study.

BACKGROUND: Randomized, comparative studies evaluating augmented secondary intention healing (SIH) compared with conventional SIH in dermatologic surgery are limited. This study aimed to evaluate whether the use of a novel biomaterial enhances SIH, particularly in shortening time to complete re-epithelialization. OBJECTIVE: The purpose of this study was to elucidate whether a novel biomaterial containing gelatin, manuka honey, and hydroxyapatite enhances SIH when compared with conventional SIH for surgical defects after Mohs micrographic surgery (MMS) on the head and distal lower extremities. MATERIALS AND METHODS: Thirty-seven patients were enrolled in this randomized controlled trial. Patients undergoing MMS on the head or distal lower extremities were eligible for recruitment. After clear surgical margins were obtained post-MMS, patients were randomized to receive standard SIH or biomaterial enhanced SIH. Patients had regularly scheduled follow-ups with questionnaires at each visit until complete re-epithelialization was achieved. RESULTS: Overall, there was no significant difference in time to re-epithelialization between standard SIH and biomaterial-enhanced SIH. However, there was a significant decrease in pain scores and skin thickness in the biomaterial-enhanced SIH group. CONCLUSION: Biomaterial-enhanced SIH is noninferior to standard SIH and produces less pain and favorable skin thickness compared with standard SIH. ClinicalTrials.gov listing: NCT04545476.

Low prevalence of bone mineral density testing in patients with systemic lupus erythematosus and glucocorticoid exposure.

SummaryPatients with systemic lupus erythematosus (SLE) have an increased risk of developing osteoporosis and fractures due to systemic inflammation and glucocorticoids (GCs). Professional organizations recommend bone mineral density (BMD) testing in SLE patients on GCs, especially within 6 months of initiation. Using a validated algorithm, we identified SLE patients in an electronic health record cohort with long-term GC exposure (≥90 days). Our primary outcome was ever BMD testing. We assessed the impact of patient and provider factors on testing. We identified 693 SLE cases with long-term GC exposure, 41% of whom had BMD testing performed. Only 18% of patients had BMD testing within 6 months of GC initiation. In a logistic regression model for BMD testing, male sex (OR = 0.49, 95% CI 0.27 - 0.87, p = 0.01) was associated with being less likely to have BMD testing after adjusting for race and ethnicity. In contrast, older age (OR = 1.04, p < 0.001) and nephritis (OR = 1.83, p = 0.003) were associated with being more likely to have BMD testing after adjusting for race and ethnicity. Bone health in SLE patients remains an area in need of improvement with attention to patients who are younger and male.

Characteristics of Lower Extremity Infection Rates Following Mohs Micrographic Surgery.

BACKGROUND: Surgical site infection (SSI) is the most common complication for Mohs micrographic surgery (MMS). Lower extremity surgical sites are at an increased risk for developing SSI. OBJECTIVE: This study aimed to evaluate lower extremity SSI rates post-MMS based on closure type and antibiotic usage. MATERIALS AND METHODS: A retrospective review was performed of all lower extremity MMS cases from 2011 to 2016 at Vanderbilt University Medical Center. Patient history, surgical details, and follow-up appointments were reviewed. RESULTS: Six hundred twenty MMS lower extremity surgeries were eligible. Review identified an overall lower extremity SSI rate of 7.4%. Infection rates were significantly increased in wound closed by flaps/grafts (p < .001). Although wound size and preoperative antibiotic prophylaxis were initially associated with increased infection rate (p = .03, p = .015), the associations were fully attenuated when adjusting for closure type. CONCLUSION: More complicated repair techniques (flap/graft) for larger wound sizes contribute to increased SSI risk among lower extremity MMS cases. Providers can use this information to guide antibiotic prophylaxis.

Clinical and Histopathologic Characteristics of Metastatic and Locally Advanced Cutaneous Basal Cell Carcinomas.

ABSTRACT: Locally advanced or metastatic basal cell carcinomas (laBCCs or mBCCs) are rare, with few case series providing information on their epidemiology. We aimed to describe the clinical and histologic features of locally advanced and metastatic basal cell carcinomas. Forty cases of laBCC or mBCC were identified by searching Vanderbilt's database from 1984 to January 2019. A retrospective chart review was performed. Pathology slides were available for 23 cases (13 mBCCs and 10 laBCCs). Twenty-one of 23 cases were Clark level IV or V, with a mean depth of invasion of >7 mm for both types. The mean mitotic rate was 4.4 mitoses/mm2 for laBCCs and 3.3 mitoses/mm2 for mBCCs. Ulceration was identified in 7 laBCC and 8 mBCC cases. Perineural invasion was present in 2 laBCC and 6 mBCC cases, with 3 mBCCs invading nerves >0.1 mm. Of 13 mBCC cases, histologic subtypes included infiltrative (n = 9), nodular (n = 7), morpheaform (n = 4), and superficial (n = 2), with multiple patterns present in some specimens. 10 of 13 patients with mBCC had local recurrence before metastasis. In summary, we identified several potential markers of high-risk BCC, including perineural invasion, deep invasion, elevated mitotic rate, and local recurrence of the primary tumor.

Mitotic rate is associated with positive lymph nodes in patients with thin melanomas.

BACKGROUND: The American Joint Commission on Cancer will remove mitotic rate from its staging guidelines in 2018. OBJECTIVE: Using a large nationally representative cohort, we examined the association between mitotic rate and lymph node positivity among thin melanomas. METHODS: A total of 149,273 thin melanomas in the National Cancer Database were examined for their association of high-risk features of mitotic rate, ulceration, and Breslow depth with lymph node status. RESULTS: Among 17,204 patients with thin melanomas with data on Breslow depth, ulceration, and mitotic rate who underwent a lymph node biopsy, there was a strong linear relationship between odds of having a positive lymph node and mitotic rate (R2 = 0.96, P < .0001, ß = 3.31). The odds of having a positive node increased by 19% with each 1-point increase in mitotic rate (odds ratio, 1.19; 95% confidence interval, 1.17-1.21). Cases with negative nodes had a mean mitotic rate of 1.54 plus or minus 2.07 mitoses/mm2 compared with 3.30 plus or minus 3.54 mitoses/mm2 for those with positive nodes (P < .0001). LIMITATIONS: The data collected do not allow for survival analyses. CONCLUSIONS: Mitotic rate was strongly associated with the odds of having a positive lymph node and should continue to be reported on pathology reports.

Calpain inhibition reduces structural and functional impairment of retinal ganglion cells in experimental optic neuritis.

Optic neuritis (ON), inflammation of the optic nerve, is strongly associated with multiple sclerosis. ON pathology is characterized by attack of autoreactive T cells against optic nerve antigens, resulting in demyelination, death of retinal ganglion cells, and cumulative visual impairment. A model of experimental autoimmune encephalomyelitis (EAE) was utilized to study the onset and progression of ON and the neuroprotective efficacy of oral treatment with the calpain inhibitor SNJ 1945. EAE was actively induced in B10.PL mice with myelin basic protein on Days 0 and 2, and mice received twice daily oral dosing of SNJ 1945 from Day 9 until sacrificing (Day 26). Visual function was determined by electroretinogram recordings and daily measurement of optokinetic responses (OKR) to a changing pattern stimulus. Optic nerve and retinal histopathology was investigated by immunohistochemical and luxol fast blue staining. EAE mice manifested losses in OKR thresholds, a measurement of visual acuity, which began early in the disease course. There was a significant bias toward unilateral OKR impairment among EAE-ON eyes. Treatment with SNJ 1945, initiated after the onset of OKR threshold decline, improved visual acuity, pattern electroretinogram amplitudes, and paralysis, with attenuation of retinal ganglion cell death. Furthermore, calpain inhibition spared oligodendrocytes, prevented degradation of axonal neurofilament protein, and attenuated reactive astrocytosis. The trend of early, unilateral visual impairment in EAE-ON parallels the clinical presentation of ON exacerbations associated with multiple sclerosis. Calpain inhibition may represent an ideal candidate therapy for the preservation of vision in clinical ON. As in multiple sclerosis (MS) patients, optic neuritis (ON) and early, primarily monocular loss in spatial acuity is observed in a rodent model (EAE, experimental autoimmune encephalomyelitis). Daily oral treatment with the calpain inhibitor SNJ 1945 preserves visual acuity and preserves retinal ganglion cells (Brn3a, brain-specific homeobox/POU domain protein 3A) and their axons (MOSP, myelin oligodendrocyte-specific protein). Calpain inhibition may represent a candidate therapy for the preservation of vision in ON.

Case report and cohort analysis of drug-induced liver injury associated with daptomycin.

A patient receiving daptomycin developed asymptomatic transaminitis and hyperbilirubinemia without concurrent multiorgan dysfunction or elevation of his creatinine kinase level. After ruling out other etiologies, the liver injury was attributed to daptomycin and was subsequently resolved. A single-center retrospective cohort analysis of baseline and follow-up liver function panels (n = 614) from all admissions from 2008 to 2013 during which daptomycin was administered did not reveal any other cases of probable or definite drug-induced liver injury associated with daptomycin.

Skin cancer in organ transplant recipients: more than the immune system.

Organ transplant recipients (OTRs) are at increased risk of developing nonmelanoma skin cancers. This has long been thought to be caused by immunosuppression and viral infection. However, skin cancer risk among individuals with AIDS or iatrogenic immunodeficiency does not approach the levels seen in OTRs, suggesting other factors play a critical role in oncogenesis. In clinical trials of OTRs, switching from calcineurin inhibitors to mammalian target of rapamycin inhibitors consistently led to a significant reduction in the risk of developing new skin cancers. New evidence suggests calcineurin inhibitors interfere with p53 signaling and nucleotide excision repair. These two pathways are associated with nonmelanoma skin cancer, and squamous cell carcinoma in particular. This finding may help explain the predominance of squamous cell carcinoma over basal cell carcinoma in this population. Mammalian target of rapamycin inhibitors do not appear to impact these pathways. Immunosuppression, viral infection, and impaired DNA repair and p53 signaling all interact in OTRs to create a phenotype of extreme risk for nonmelanoma skin cancer.

Voriconazole metabolism is associated with the number of skin cancers per patient.

Voriconazole exposure is associated with skin cancer, but it is unknown how the full spectrum of its metabolizer phenotypes impacts this association. We conducted a retrospective cohort study to determine how variation in metabolism of voriconazole as measured by metabolizer status of CYP2C19 is associated with the total number of skin cancers a patient develops and the rate of development of the first skin cancer after treatment. There were 1,739 organ transplant recipients with data on CYP2C19 phenotype. Of these, 134 were exposed to voriconazole. There was a significant difference in the number of skin cancers after transplant based on exposure to voriconazole, metabolizer phenotype, and the interaction of these two (p < 0.01 for all three). This increase was driven primarily by number of squamous cell carcinomas among rapid metabolizes with voriconazole exposure (p < 0.01 for both). Patients exposed to voriconazole developed skin cancers more rapidly than those without exposure (Fine-Grey hazard ratio 1.78, 95% confidence interval 1.19-2.66). This association was similarly driven by development of SCC (Fine-Grey hazard ratio 1.83, 95% confidence interval 1.14-2.94). Differences in voriconazoles metabolism are associated with an increase in the number of skin cancers developed after transplant, particularly SCC.

Voriconazole Metabolism is Associated with the Number of Skin Cancers Per Patient.

Voriconazole exposure is associated with skin cancer, but it is unknown how the full spectrum of its metabolizer phenotypes impacts this association. We conducted a retrospective cohort study to determine how variation in metabolism of voriconazole as measured by metabolizer status of CYP2C19 is associated with the total number of skin cancers a patient develops and the rate of development of the first skin cancer after treatment. There were 1,739 organ transplant recipients with data on CYP2C19 phenotype. Of these, 134 were exposed to voriconazole. There was a significant difference in the number of skin cancers after transplant based on exposure to voriconazole, metabolizer phenotype, and the interaction of these two (p < 0.01 for all three). This increase was driven primarily by number of squamous cell carcinomas among rapid metabolizes with voriconazole exposure (p < 0.01 for both). Patients exposed to voriconazole developed skin cancers more rapidly than those without exposure (Fine-Grey hazard ratio 1.78, 95% confidence interval 1.19-2.66). This association was similarly driven by development of SCC (Fine-Grey hazard ratio 1.83, 95% confidence interval 1.14-2.94). Differences in voriconazoles metabolism are associated with an increase in the number of skin cancers developed after transplant, particularly SCC.

Toward personalized skin cancer care: multiple skin cancer development in five cohorts.

Importance: Many patients will develop more than one skin cancer, however most research to date has examined only case status. Objective: Describe the frequency and timing of the treatment of multiple skin cancers in individual patients over time. Design: Longitudinal claims and electronic health record-based cohort study. Setting: Vanderbilt University Medical Center database called the Synthetic Derivative, VA, Medicare, Optum Clinformatics® Data Mart Database, IBM Marketscan. Participants: All patients with a Current Procedural Terminology code for the surgical management of a skin cancer in each of five cohorts. Exposures: None. Main Outcomes and Measures: The number of CPT codes for skin cancer treatment in each individual occurring on the same day as an ICD code for skin cancer over time. Results: Our cohort included 5,508,374 patients and 13,102,123 total skin cancers treated. Conclusions and Relevance: Nearly half of patients treated for skin cancer were treated for more than one skin cancer. Patients who have not developed a second skin cancer by 2 years after the first are unlikely to develop multiple skin cancers within the following 5 years. Better data formatting will allow for improved granularity in identifying individuals at high risk for multiple skin cancers and those unlikely to benefit from continued annual surveillance. Resource planning should take into account not just the number of skin cancer cases, but the individual burden of disease.