Neurologic Complications of Babesiosis, United States, 2011-2021.

Babesiosis is a globally distributed parasitic infection caused by intraerythrocytic protozoa. The full spectrum of neurologic symptoms, the underlying neuropathophysiology, and neurologic risk factors are poorly understood. Our study sought to describe the type and frequency of neurologic complications of babesiosis in a group of hospitalized patients and assess risk factors that might predispose patients to neurologic complications. We reviewed medical records of adult patients who were admitted to Yale-New Haven Hospital, New Haven, Connecticut, USA, during January 2011-October 2021 with laboratory-confirmed babesiosis. More than half of the 163 patients experienced >1 neurologic symptoms during their hospital admissions. The most frequent symptoms were headache, confusion/delirium, and impaired consciousness. Neurologic symptoms were associated with high-grade parasitemia, renal failure, and history of diabetes mellitus. Clinicians working in endemic areas should recognize the range of symptoms associated with babesiosis, including neurologic.

The impact of ABO and RhD blood types on Babesia microti infection.

BACKGROUND: Babesiosis is an emerging infectious disease caused by intraerythrocytic Babesia parasites that can cause severe disease and death. While blood type is known to affect the mortality of Plasmodium falciparum malaria patients, associations between red blood cell (RBC) antigens and Babesia microti infection and disease severity are lacking. METHODS: We evaluated RhD and ABO blood types of Babesia-infected (18S rRNA reactive) blood donors in 10 endemic states in the Northeastern and northern Midwestern United States. We also assessed possible associations between RhD and ABO blood types and disease severity among hospitalized babesiosis patients in Connecticut. RESULTS: A total of 768 Babesia-infected blood donors were analyzed, of which 750 (97.7%) had detectable B. microti-specific antibodies. B. microti-infected blood donors were more likely to be RhD- (OR of 1.22, p-value 0.024) than RhD+ donors. Hospitalized RhD- babesiosis patients were more likely than RhD+ patients to have high peak parasitemia (p-value 0.017), which is a marker for disease severity. No differences in RhD+ blood type were noted between residents of the Northeast (OR of 0.82, p-value 0.033) and the Midwest (OR of 0.74, p-value 0.23). Overall, ABO blood type was not associated with blood donor B. microti infection, however, B. microti-infected donors in Maine and New Jersey were more likely to be blood type B compared to non-type B (OR 2.49 [p = 0.008] and 2.07 [p = 0.009], respectively), while infected donors from Pennsylvania were less likely to be type B compared to non-type B (OR 0.32 [p = 0.02]). CONCLUSIONS: People expressing RhD antigen may have a decreased risk of B. microti infection and babesiosis severity. The association of B antigen with B. microti infection is less clear because the antigen appeared to be less prevalent in infected Pennsylvania blood donors but more prevalent in Maine and New Jersey infected donors. Future studies should quantify associations between B. microti genotypes, RBC antigens, and the frequency and severity of B. microti infection to increase our understanding of human Babesia pathogenesis and improve antibody, vaccine, and RBC exchange transfusion strategies.

Prosthetic Joint Infections of the Hip and Knee Among the Elderly: A Retrospective Study.

BACKGROUND: As the population ages and demand for total joint arthroplasty increases, rates of periprosthetic joint infection are expected to increase in the geriatric population. Studies comparing prevalence of risk factors, etiology, management, and mortality of prosthetic joint infection in older patients are lacking. METHODS: We compared clinical characteristics, management, and mortality of patients <75 vs ≥75 years of age with first prosthetic joint infection of the hip or knee admitted to a tertiary medical center between September 2017 and December 2019. RESULTS: Ninety-eight patients (<75 years of age [n = 63]; ≥75 years of age (n = 35) were studied. Groups were similar in terms of etiology, culture-directed therapy, antibiotic suppression, and length of stay. There was no difference in surgical management, performed in almost 97% of cases in both groups. Arrhythmia and heart failure were more prevalent in those aged ≥75 years. Readmission related to prosthetic joint infection occurred less often in older individuals (P = .005). Deaths within 1 year of diagnosis were rare (n = 4; 4.1%), occurring in older patients and resulting mostly from sepsis. CONCLUSION: In our single-center study, patients with first prosthetic joint infection had similar management, regardless of age. We identified cardiac history as one of the host factors for prosthetic joint infection most seen in patients ≥75 years of age. Although deaths were rare, 1-year mortality was higher in patients aged ≥75. Prospective, multicenter studies are needed to explore risk factors and management strategies of prosthetic joint infection among elderly populations.

Cardiac Complications of Human Babesiosis.

BACKGROUND: Human babesiosis is a worldwide emerging tick-borne disease caused by intraerythrocytic protozoa. Most patients experience mild to moderate illness, but life-threatening complications can occur. Although cardiac complications are common, the full spectrum of cardiac disease and the frequency, risk factors, and outcomes in patients experiencing cardiac complications are unclear. Accordingly, we carried out a record review of cardiac complications among patients with babesiosis admitted to Yale-New Haven Hospital over the last decade to better characterize cardiac complications of babesiosis. METHODS: We reviewed the medical records of all adult patients with babesiosis admitted to Yale-New Haven Hospital from January 2011 to October 2021, confirmed by identification of Babesia parasites on thin blood smear and/or by polymerase chain reaction. The presence of Lyme disease and other tick-borne disease coinfections were recorded. RESULTS: Of 163 enrolled patients, 32 (19.6%) had ≥1 cardiac complication during hospitalization. The most common cardiac complications were atrial fibrillation (9.4%), heart failure (8.6%), corrected QT interval prolongation (8.0%), and cardiac ischemia (6.8%). Neither cardiovascular disease risk factors nor preexisting cardiac conditions were significantly associated with the development of cardiac complications. The cardiac complication group had a greater prevalence of high-grade parasitemia (>10%) (P < .001), longer median length of both hospital (P < .001) and intensive care unit stay (P < .001), and a higher mortality rate (P = .02) than the group without cardiac complications. CONCLUSIONS: Cardiac complications of acute babesiosis are common and occurred in approximately one-fifth of this inpatient sample. Further investigation is needed to elucidate the relationship between babesiosis severity and cardiac outcomes.

Sex differences in early and term placenta are conserved in adult tissues.

BACKGROUND: Pregnancy complications vary based on the fetus's genetic sex, which may, in part, be modulated by the placenta. Furthermore, developmental differences early in life can have lifelong health outcomes. Yet, sex differences in gene expression within the placenta at different timepoints throughout pregnancy and comparisons to adult tissues remains poorly characterized. METHODS: Here, we collect and characterize sex differences in gene expression in term placentas (≥ 36.6 weeks; 23 male XY and 27 female XX). These are compared with sex differences in previously collected first trimester placenta samples and 42 non-reproductive adult tissues from GTEx. RESULTS: We identify 268 and 53 sex-differentially expressed genes in the uncomplicated late first trimester and term placentas, respectively. Of the 53 sex-differentially expressed genes observed in the term placentas, 31 are also sex-differentially expressed genes in the late first trimester placentas. Furthermore, sex differences in gene expression in term placentas are highly correlated with sex differences in the late first trimester placentas. We found that sex-differential gene expression in the term placenta is significantly correlated with sex differences in gene expression in 42 non-reproductive adult tissues (correlation coefficient ranged from 0.892 to 0.957), with the highest correlation in brain tissues. Sex differences in gene expression were largely driven by gene expression on the sex chromosomes. We further show that some gametologous genes (genes with functional copies on X and Y) will have different inferred sex differences if the X-linked gene expression in females is compared to the sum of the X-linked and Y-linked gene expression in males. CONCLUSIONS: We find that sex differences in gene expression are conserved in late first trimester and term placentas and that these sex differences are conserved in adult tissues. We demonstrate that there are sex differences associated with innate immune response in late first trimester placentas but there is no significant difference in gene expression of innate immune genes between sexes in healthy full-term placentas. Finally, sex differences are predominantly driven by expression from sex-linked genes.

Prevalence and Predictors of Seizure Clusters in Pediatric Patients With Epilepsy: The Harvard-Yale Pediatric Seizure Cluster Study.

BACKGROUND: Determine the prevalence of seizure clusters (two or more seizures in six hours), use of rescue medications, and adverse outcomes associated with seizure clusters in pediatric patients with a range of epilepsy severities, and identify risk factors predictive of seizure clusters. METHODS: Prospective observational two-center study, including phone call and seizure diary follow-up for 12 months in patients with epilepsy aged one month to 18 years. We classified patients into three risk groups based on seizures within the prior year: high, seizure cluster (two or more seizures within one day); intermediate, at least one seizure but no days with two or more seizures; low, no seizures. RESULTS: One-third (32.3%; high risk, 72.4%; intermediate risk, 30.4%; low risk, 3.1%) of 297 patients had a seizure cluster during the study, including half (46.2%) of the patients with active seizures at baseline (intermediate- and high-risk groups combined). Emergency room visits or injuries were no more likely due to a seizure cluster than an isolated seizure. Rescue medications were utilized in 15.8% of patients in the high-risk group and 19.2% in the intermediate-risk group. History of status epilepticus (adjusted odds ratio [aOR], 2.13; confidence interval [CI], 1.09 to 4.16]), seizure frequency greater than four per month (aOR, 4.27; CI, 1.92 to 9.50), and high-risk group status (aOR, 6.42; CI, 2.97 to 13.87) were associated with greater odds of seizure cluster. CONCLUSIONS: Seizure clusters are common in pediatric patients with epilepsy. High seizure frequency was the strongest predictor of clusters. Rescue medications were underutilized. Future studies should evaluate the applicability and effectiveness of these medications for optimization of pediatric seizure cluster treatment and reduction of seizure-related emergency department visits, injuries, and mortality.

Erratum: X chromosome inactivation in the human placenta is patchy and distinct from adult tissues.

[This corrects the article DOI: 10.1016/j.xhgg.2022.100121.].

Insulin increases placental triglyceride as a potential mechanism for fetal adiposity in maternal obesity.

OBJECTIVE: Maternal obesity increases the incidence of excess adiposity in newborns, resulting in lifelong diabetes risk. Elevated intrauterine fetal adiposity has been attributed to maternal hyperglycemia; however, this hypothesis does not account for the increased adiposity seen in newborns of mothers with obesity who have euglycemia. We aimed to explore the placental response to maternal hyperinsulinemia and the effect of insulin-like growth factor 2 (IGF-2) in promoting fetal adiposity by increasing storage and availability of nutrients to the fetus. METHODS: We used placental villous explants and isolated trophoblasts from normal weight and obese women to assess the effect of insulin and IGF-2 on triglyceride content and insulin receptor signaling. Stable isotope tracer methods were used ex vivo to determine effect of hormone treatment on de novo lipogenesis (DNL), fatty acid uptake, fatty acid oxidation, and esterification in the placenta. RESULTS: Here we show that placentae from euglycemic women with normal weight and obesity both have abundant insulin receptor. Placental depth and triglyceride were greater in women with obesity compared with normal weight women. In syncytialized placental trophoblasts and villous explants, insulin and IGF-2 activate insulin receptor, induce expression of lipogenic transcription factor SREBP-1 (sterol regulatory element-binding protein 1), and stimulate triglyceride accumulation. We demonstrate elevated triglyceride is attributable to increased esterification of fatty acids, without contribution from DNL and without an acceleration of fatty acid uptake. CONCLUSIONS: Our work reveals that obesity-driven aberrations in maternal metabolism, such as hyperinsulinemia, alter placental metabolism in euglycemic conditions, and may explain the higher prevalence of excess adiposity in the newborns of obese women.

Correction: Kumar et al. The Global Emergence of Human Babesiosis. Pathogens 2021, 10, 1447.

In the original publication [...].

X chromosome inactivation in the human placenta is patchy and distinct from adult tissues.

In humans, one of the X chromosomes in genetic females is inactivated by a process called X chromosome inactivation (XCI). Variation in XCI across the placenta may contribute to observed sex differences and variability in pregnancy outcomes. However, XCI has predominantly been studied in human adult tissues. Here, we sequenced and analyzed DNA and RNA from two locations from 30 full-term pregnancies. Implementing an allele-specific approach to examine XCI, we report evidence that XCI in the human placenta is patchy, with large patches of either maternal or paternal X chromosomes inactivated. Further, using similar measurements, we show that this is in contrast to adult tissues, which generally exhibit mosaic X inactivation, where bulk samples exhibit both maternal and paternal X chromosome expression. Further, by comparing skewed samples in placenta and adult tissues, we identify genes that are uniquely inactivated or expressed in the placenta compared with adult tissues, highlighting the need for tissue-specific maps of XCI.

Correction: Kumar et al. The Global Emergence of Human Babesiosis. Pathogens 2021, 10, 1447.

There were two factual errors in the original publication of our manuscript [...].

Seizing the Window of Opportunity Within 1 Year Postpartum: Early Cardiovascular Screening.

Background Our objective was to assess new chronic hypertension 6 to 12 months postpartum for those with hypertensive disorder of pregnancy (HDP) compared with normotensive participants. Methods and Results We performed a prospective cohort study of participants with singleton gestations and no known preexisting medical conditions who were diagnosed with HDP compared with normotensive women with no pregnancy complications (non-HDP). Participants underwent cardiovascular risk assessment 6 to 12 months after delivery. Primary outcome was onset of new chronic hypertension at 6 to 12 months postpartum. We also examined lipid values, metabolic syndrome, prediabetes, diabetes, and 30-year cardiovascular disease (CVD) risk. Multivariable logistic regression was performed to assess the association between HDP and odds of a postpartum diagnosis of chronic hypertension while adjusting for parity, body mass index, insurance, and family history of CVD. There were 58 participants in the HDP group and 51 participants in the non-HDP group. Baseline characteristics between groups were not statistically different. Participants in the HDP group had 4-fold adjusted odds of developing a new diagnosis of chronic hypertension 6 to 12 months after delivery, compared with those in the non-HDP group (adjusted odds ratio, 4.60 [95% CI, 1.65-12.81]), when adjusting for body mass index, parity, family history of CVD, and insurance. Of the HDP group, 58.6% (n=34) developed new chronic hypertension. Participants in the HDP group had increased estimated 30-year CVD risk and were more likely to have metabolic syndrome, a higher fasting blood glucose, and higher low-density lipoprotein cholesterol. Conclusions Participants without known underlying medical conditions who develop HDP have 4-fold increased odds of new diagnosis of chronic hypertension by 6 to 12 months postpartum as well as increased 30-year CVD risk scores. Implementation of multidisciplinary care models focused on CVD screening, patient education, and lifestyle interventions during the first year postpartum may serve as an effective primary prevention strategy for the development of CVD.

Unnecessary Routine Use of Mycobacterial Cultures in Patients With Periprosthetic Joint Infections.

Accurate diagnosis ensures appropriate therapy of periprosthetic joint infection (PJI). Since mycobacterial PJI is rare, routine testing is inappropriate. We reviewed hip and knee PJI at our institution over 28 months. Mycobacterial cultures were routinely sent with rare positivity. Mycobacterial cultures should be sent only when there is clinical suspicion.

The Global Emergence of Human Babesiosis.

Babesiosis is an emerging tick-borne disease caused by intraerythrocytic protozoa that are primarily transmitted by hard-bodied (ixodid) ticks and rarely through blood transfusion, perinatally, and organ transplantation. More than 100 Babesia species infect a wide spectrum of wild and domestic animals worldwide and six have been identified as human pathogens. Babesia microti is the predominant species that infects humans, is found throughout the world, and causes endemic disease in the United States and China. Babesia venatorum and Babesia crassa-like agent also cause endemic disease in China. Babesia divergens is the predominant species in Europe where fulminant cases have been reported sporadically. The number of B. microti infections has been increasing globally in recent decades. In the United States, more than 2000 cases are reported each year, although the actual number is thought to be much higher. In this review of the epidemiology of human babesiosis, we discuss epidemiologic tools used to monitor disease location and frequency; demographics and modes of transmission; the location of human babesiosis; the causative Babesia species in the Americas, Europe, Asia, Africa, and Australia; the primary clinical characteristics associated with each of these infections; and the increasing global health burden of this disease.

Prevalence and Risk Factors for Nonsuicidal Self-Injury in Transgender and Gender-Expansive Youth at a Rural Gender Wellness Clinic.

Purpose: Transgender and gender-expansive (TGE) populations are at increased risk for nonsuicidal self-injury (NSSI). Rural TGE populations are understudied and underserved in terms of mental health services. The purpose of this study was to determine lifetime prevalence of NSSI among TGE youth at a rural gender wellness clinic and identify demographic and clinical characteristics associated with NSSI. Methods: The Gender Wellness Center Pediatric Patient Registry, a comprehensive database of 185 TGE youth ≤25 years of age, provided an estimate of the lifetime prevalence of NSSI. Univariate logistic regression models were utilized to test associations between patient demographic and clinical characteristics and NSSI. Variables that met the threshold for significance in the univariate analyses (p<0.05) were entered into a multivariate logistic regression model. All statistical analyses were conducted in SAS v.9.4. Results: Prevalence of NSSI in the sample was 36.8% (n=68). In unadjusted logistic regression models, risk factors for NSSI included female assigned sex at birth, transmasculine spectrum gender identity, history of mood disorder, history of suicidal ideation (SI) or attempt, and history of abuse (p<0.05). In the adjusted model, variables significantly associated with NSSI included female assigned sex at birth, history of mood disorder, and history of SI or attempt. Conclusion: NSSI was highly prevalent in this sample of rural TGE youth, confirming the need for screening and early interventions that target the unique vulnerabilities of TGE youth. The complex interplay of sex assigned at birth, mood disorders, and NSSI requires further research.

Parasite burden and red blood cell exchange transfusion for babesiosis.

BACKGROUND: The association between parasite burden and end-organ dysfunction in subjects with Babesia microti infection has not been extensively studied, nor has the optimal role of red blood cell exchange (RCE) transfusion in babesiosis treatment. This retrospective chart review evaluates the associations between parasitemia, end-organ dysfunction, and outcomes in babesiosis patients treated with antimicrobial agents and RCE compared to those treated with antimicrobial agents alone. MATERIALS AND METHODS: We evaluated adults (≥18 years of age) with laboratory-confirmed babesiosis who were admitted between 2011 and 2017 to Yale New Haven Hospital, located in a Babesia-endemic region of the Northeastern United States. Patient demographics, parasitemia levels, clinical and laboratory indicators of end-organ dysfunction, and outcomes were examined. RESULTS: Ninety-one subjects (mean age 65.1 years, 69.2% male) were studied. Subjects were stratified according to peak parasitemia: <1% (n = 34), 1-5% (n = 24), 5-10% (n = 15), and >10% (n = 18). Laboratory measures indicating degrees of hemolysis, coagulopathy, and pulmonary, renal and hepatic dysfunction differed significantly across peak parasitemia levels. Median length of hospital stay increased with each successive peak parasitemia level (P < .001). These results indicate a strong association between peak parasitemia level and disease severity. Nineteen subjects underwent RCE, all with peak parasitemia ≥9% and some degree of end-organ dysfunction. CONCLUSIONS: Babesia microti parasitemia is closely associated with disease severity, though not all subjects with end-organ dysfunction had high-grade parasitemia. Our data suggest that the use of parasitemia >10%, coupled with clinical status, is a reasonable indicator for RCE in babesiosis patients.

Health-related quality of life among transgender and gender expansive youth at a rural gender wellness clinic.

PURPOSE: To address a critical gap in the existing Health-Related Quality of Life (HRQOL) literature by quantifying and describing HRQOL among transgender and gender expansive (TG/GE) youth at a rural gender clinic and comparing the HRQOL of these youth to age-stratified United States (U.S.) population standards. METHODS: This cross-sectional study includes results of the baseline HRQOL assessment of 141 TG/GE patients enrolled in the Gender Wellness Center (GWC) Pediatric Patient Registry. HRQOL was assessed using the Child Health Questionnaire-Child Form 87 (CHQ-CF87; ages < 18) and the Short Form-36 (SF-36v2; ages 18-21). Mean subscale scores were compared to the most current U.S. population standards available. RESULTS: On all but one of the CHQ-CF87 subscales, TG/GE youth scored significantly lower than 2015-2016 U.S. general population youth and youth with two chronic conditions. On the SF-36v2, TG/GE youth scored significantly higher than 2009 U.S. standards on all physical health domains but lower on all but one of the mental health domains. CONCLUSIONS: Cross-sectional HRQOL data from a registry of TG/GE youth indicate significantly poorer mental health measures as compared with the U.S. general population. Longitudinal assessments are needed to evaluate whether HRQOL improves with gender-affirming care. Future studies should aim to identify sociocultural factors at the intersection of rurality and health that contribute to diminished HRQOL among rural TG/GE youth.

Building a Pediatric Patient Registry to Study Health Outcomes Among Transgender and Gender Expansive Youth at a Rural Gender Clinic.

Purpose: Significant knowledge gaps regarding outcomes of gender-affirming therapy in transgender (TG) and gender expansive (GE) youth impede an evidence-based approach to these patients. The Gender Wellness Center (GWC) Pediatric Patient Registry was established in 2017 to enable systematic, longitudinal research to describe the physical, mental, and quality-of-life outcomes of these youth. Methods: All TG/GE youth, ages 8-21 years, presenting to the GWC were recruited on site. Ten research questions guided the creation of data fields. The following 131 variables were abstracted from electronic medical records: demographics, weight, height, body mass index, gender identity, sexual orientation, coexisting diagnoses, substance use, Tanner stage, sexual activity, medications, fertility preservation, Gonadotropin Releasing Hormone (GnRH) analog use, hormone therapy, surgery, and related outcomes. Health-related quality of life is assessed using the Child Health Questionnaire-87 for ages <18 and the Short Form-36 for ages 18-21. Results: To date, 139 TG and GE youth (90% white and 93% non-Hispanic), have enrolled in the registry. Average age at enrollment was 17.5 years (±3.1, range: 8-21). Two-thirds of youth identified on the trans masculine spectrum (n=90), 28.8% identified on the trans feminine spectrum (n=40), and 6.5% identified as nonbinary/gender nonconforming (n=9). Nearly, all youth had socially transitioned (n=121, 87.7%) and were medically transitioning (n=123, 89.1%). Conclusion: As one of the first rural-based registries, the GWC Registry has helped to delineate health outcomes attributable to gender-affirming care in a unique patient population of TG/GE youth. Our results will be used to describe treatment outcomes that will contribute to evidence-based guidelines.

Prevalence and predictors of seizure clusters: A prospective observational study of adult patients with epilepsy.

OBJECTIVE: The purpose of this prospective observational study was to describe the prevalence and adverse outcomes associated with seizure clusters (defined as ≥2 seizures in a 6-hour period) in a large sample of adult patients with a range of epilepsy severities and to identify clinical characteristics predictive of clustering. METHODS: Patients maintained a seizure diary and were contacted monthly to verify compliance and data accuracy. Logistic regression models were utilized to test associations between individual patient demographic/clinical characteristics and seizure clustering. Fisher's exact test was utilized to test associations between rescue medication use and adverse seizure-related outcomes. RESULTS: A total of 300 patients were followed prospectively for one year; 247 patients qualified for final analysis. Six-hour seizure clusters occurred in 45.8% of patients with active epilepsy at enrollment, including 62.7% of those with prior day-clusters and 30.0% of those without prior day-clusters. The odds of clustering were markedly greater among patients who reported a higher seizure frequency (>4 seizures per year vs. 1-4 seizures per year) (adjusted odds ratio (OR): 8.9; 95% confidence interval (CI): 3.2-24.6; p < 0.0001) and among patients with prior day-clusters (adjusted OR: 11.0; 95% CI: 1.2-104.2; p = 0.036). Rescue medication use was associated with significantly fewer injuries and emergency department visits, but rescue medication was underutilized. CONCLUSIONS: Seizure clusters are common, occurring in nearly half of adult patients with active epilepsy followed prospectively over one year, and are more frequent in those with higher seizure frequencies and prior day-clusters. Although underutilized, rescue medication was associated with fewer injuries and emergency department visit.

Mammary Myofibroblastoma in a Transgender Patient on Feminizing Hormones: Literature Review and Case Report.

Purpose: Defining the risk of neoplasia associated with gender-affirming hormone therapy (GAHT) is a priority for transgender medical research. The purposes of this article are to present a unique case of breast neoplasia in a transgender individual and to review the existing evidence base on GAHT as a potential risk for breast pathology. Methods: We present the case of a 76-year-old transgender patient who developed an estrogen receptor-positive mammary myofibroblastoma (MFB) after 13 months of treatment on feminizing hormones. To our knowledge, this is the first reported case of MFB occurring in a transgender individual. A literature review was conducted to identify all reported cases of breast neoplasia among transgender individuals receiving feminizing GAHT. Information was abstracted from each of the included cases to describe the existing body of literature and to compare published cases to the case reported in this study. Results: We identified a total of 19 malignant and 3 benign cases of breast neoplasia among transgender women. Ours is the first reported case of MFB in a transgender individual receiving feminizing hormones and the first reported case of breast neoplasia associated with GAHT administered via the estradiol patch. Conclusion: This case reinforces the need for additional reporting of breast neoplasia presenting in transgender individuals treated with feminizing hormones. The relationship between estrogen exposure and breast neoplasia in the transgender population remains poorly defined, and additional research is needed to define risks and inform clinical practice.