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Ciprofloxacin-Induced Achilles Tendinopathy in a 26-Year-Old Male
No full textRAD 2025 Award Winning Posters & Oral Presentations, Poster Highlight: Texas College of Osteopathic Medicine - Case StudyBackground: Fluoroquinolones, including ciprofloxacin, are broad-spectrum antibiotics commonly prescribed for a range of bacterial infections, including urinary tract infections (UTIs), bacterial sinusitis, pneumonia, and gastrointestinal infections. While effective, these antibiotics have been increasingly linked to adverse musculoskeletal effects, particularly collagen degradation, oxidative stress, and disruption of tendon matrix integrity, which predispose patients to tendinopathies (Sharma et al., 2020; Hall et al., 2021). The risk is highest in older adults with renal dysfunction and those on concurrent corticosteroid therapy. However, emerging evidence suggests that young, physically active individuals are also vulnerable, particularly those engaged in repetitive high-impact activities that place mechanical stress on tendons (Khurana et al., 2019). Among fluoroquinolone-associated tendinopathies, the Achilles tendon is the most frequently affected, with an incidence of 0.14% to 0.4% in the general population (Sharma et al., 2020). This case underscores the potential for fluoroquinolone-induced Achilles tendinopathy in a young, otherwise healthy individual, reinforcing the need for heightened clinical awareness of this complication beyond traditionally recognized high-risk populations. Case Presentation: A 26-year-old male presented to the outpatient clinic with a new onset 2-week history of posterior ankle pain, worsened with weight-bearing activities. The pain was sharp and localized to the Achilles tendon. He reported no recent trauma, prior tendinopathy, or systemic illnesses. His medical history was unremarkable except for a recent diagnosis of acute bacterial sinusitis, for which he was prescribed ciprofloxacin 500 mg BID for 10 days. Symptoms began 5 days into the antibiotic course and persisted after completion. He is a recreational weightlifter and runner, jogging 3–4 times per week, with no recent increase in training intensity. Physical Examination: Inspection: Mild swelling and erythema over the posterior ankle. Palpation: Tenderness 2–6 cm proximal to the Achilles tendon insertion. Range of Motion: Passive dorsiflexion elicited pain. Strength Testing: Mild weakness with plantarflexion. Thompson Test: Negative. Diagnostic Workup: Ultrasound (US): Thickened Achilles tendon with hypoechoic areas and peritendinous fluid, consistent with tendinopathy (Hall et al., 2021). Management and Outcome: Given the clinical findings and recent ciprofloxacin exposure, the diagnosis of fluoroquinolone-induced Achilles tendinopathy was established. Management included: Discontinuation of Ciprofloxacin to prevent further tendon injury. Activity Modification, advising the patient to avoid high-impact activities. Symptom Control, including NSAIDs (if tolerated) and cryotherapy (Hall et al., 2021). Physical Therapy, incorporating strengthening and mobility exercises (Sharma et al., 2020). Follow-up in 2–4 weeks to evaluate progression and recovery. The patient improved gradually over 6 weeks with conservative management. He was instructed to avoid all fluoroquinolone antibiotics indefinitely and to slowly reintegrate physical activity over the coming months to avoid reinjury. Conclusions: This case underscores the risk of fluoroquinolone-induced tendinopathy in young, otherwise healthy individuals, challenging the traditional perception that this adverse effect primarily affects older patients or those with underlying risk factors. Future research should focus on identifying genetic or biochemical markers that may predispose certain individuals to fluoroquinolone-induced tendinopathy, as well as investigating the role of alternative antibiotics with a lower musculoskeletal risk profile in susceptible populations
Visiting Student Learning Opportunities Analysis and the Cost Differences for MD, DO, and IMG students
No full textPurpose: The cost of applying to residency programs can be a large barrier for medical students in the match process. One major variable cost in the application process is the cost of away rotations. Away rotations allow a medical student to get involved with a program outside their home institution and are important for connecting with the residency programs a student has interest in. Visiting Student Learning Opportunities (“VSLO”) is a web application by the Association of American Medical Colleges which allows students to find and apply to away rotations. The aim of this article is to explore the unequal financial barriers that certain student demographics face when applying to their perspective away rotations. Methods: A detailed analysis of VSLO was conducted to show key differences in the cost associated with applying to and rotating at certain programs for various groups of medical students. The analysis compares three groups of students: MD students (Medical Doctor), DO students (Doctor of Osteopathic Medicine), and IMGs (International Medical Graduates). The data for this analysis was conducted by collecting all of the prices listed under processing and tuition fees for each program that is currently listed in the VSLO database as of March 2023. The processing and tuition fees of rotating at each of these programs were then analyzed to determine any cost difference groups of medical students. The range, mean and median in cost differences were calculated between MD, DO and IMG students. Results: This analysis of VSLO shows 249 programs in the United States that were accepting applications, with 142 of these programs requiring no processing or tuition fees. Only 4 programs reflect a difference in fees between MD and DO students, yet 24 programs have higher fees for IMG students when compared to MD and DO students. Tuition fees for IMGs can be as high as $4500 more than other students. Conclusions: IMGs historically have a lower match rate into U.S. residencies when compared to students from schools within the U.S., and these additional fees accentuate the difficulty of matching. The difference in match rates for IMGs is more drastic in competitive specialties, such as Dermatology. The importance of networking during away rotations is heavily emphasized with these competitive specialties, and differences in price for away rotations may contribute to differences in match rates for IMGs
Beta 2 Receptors Mediate Adrenergic Relaxation of the Rat Femoral Artery
No full textPoster Highlight: College of Biomedical and Translational Science, RAD 2025 Award Winning Posters & Oral PresentationsPurpose: The purpose of this study was to determine: a) the extent to which β-adrenergic agonists relax vascular smooth muscle, b) the β-receptor subtype(s) that are activated; and c) the signaling mechanisms involved. Methods: Isometric tension was recorded from 2 mm segments of femoral arteries from male and female Sprague Dawley rats. Arterial rings were contracted with the α1 agonist phenylephrine (10 µM) or 60 mM K+, which produced a stable contraction upon which mechanisms of relaxation were studied. Various pharmacological agents, including isoproterenol, dobutamine, glibenclamide, 4-aminopyridine, and ouabain were used to determine the mechanism underlying β-adrenergic mediated relaxation. Results: Isoproterenol (10 nM to 10 µM), an agonist of β1 and β2 receptors, produced full relaxation. Dobutamine (10 nM to 10 µM), a selective β1 agonist, also produced full relaxation. Contracting arteries with 60 mM K+, which depolarizes the membrane and shifts the reversal potential, abolished β-adrenergic mediated relaxation. Application of 100 µM glibenclamide (an inhibitor of ATP-dependent K+ channels) or 1 mM 4-aminopyridine (an inhibitor of voltage-gated K+ channels) affected β-adrenergic relaxation of PE contractions. Ouabain (30 µM), an inhibitor of the Na+/K+-ATPase, partially blocked β-adrenergic relaxation following PE contractions. Conclusion: These results suggest that stimulation of β2 receptors antagonize α1 adrenergic contraction through cellular mechanisms which activate the Na+/K+-ATPase. Understanding β-adrenergic mediated relaxation can reveal the basic mechanisms behind vascular regulation. Additionally, it can help guide the development of more targeted treatments for vascular diseases like hypertension by selectively focusing on those specific receptors and pathways
Retinal Proteomic Landscape and Visual Function Preservation Reveal the Therapeutic Benefits of DHED Eyedrops in Estrogen-Deprived Glaucomatous Male Rats
No full textPurpose: In females, menopause has been implicated as a risk factor for glaucomatous ocular neurodegeneration. In males, the broad-spectrum neuroprotectant hormone 17β-estradiol (E2) is produced by aromatase from testosterone. Therefore, losing this androgen due to aging and/or orchidectomy promotes vulnerability to retinal neurodegeneration and potentially permanent vision loss. Traditional E2 replacement therapies, while promising, are associated with numerous side effects, including feminization. Our lab has developed 10β,17β-dihydroxyestra-1,4-dien-3-one (DHED), a unique prodrug selectively converted into E2 in the retina upon topical administration. Consequently, our approach confines E2 formation to the retina while sparing the rest of the body from unwanted hormonal side effects. We previously reported the neuroprotective effects of DHED eyedrops under sustained ocular hypertension (OHT) in gonad-intact male and female animals. Here, we use a multipronged approach to investigate the effects of both E2 deprivation and OHT on the vision and retinal proteome of orchiectomized (ORDX) male Brown-Norway (BN) rats and the therapeutic benefits of topical DHED in these animals. Methods: Young (3 months old) male BN rats were separated into four groups (n=4): naïve, ORDX, Vehicle + OHT + ORDX, and DHED + OHT + ORDX. OHT was induced via bilateral hypertonic saline injection into an episcleral vein. Visual acuity (VA) and contrast sensitivity (CS) were measured using the OptoMotry system. DHED (0.01%) was formulated as eyedrops using a vehicle consisting of 2-hydroxylpropyl-β-cyclodextrin (20%) in saline. Retinas were collected after a 3-week, once-daily eye drop treatment and processed for data-dependent acquisition using nanoflow liquid chromatography-tandem mass spectrometry. Our global proteomics-based bioinformatics pipeline included identification, quantitation, and statistical analysis employing Proteome Discoverer, MaxQuant, and Scaffold. Ingenuity Pathway Analysis (IPA) was used to derive biological context. Differentially expressed proteins (DEPs) were selected as potential biomarkers based on statistical significance (ANOVA and Student's t-tests) and association with neuroprotection/degeneration. Validation of DEPs was conducted by targeted proteomics (parallel reaction monitoring). Results: Compared to the naïve control, visual performance was retained in the DHED-treated group (VA = 0.60 ± 0.02 c/D, CS = 11.3% ± 1.2%), in sharp contrast with the vehicle group (VA = 0.55 ± 0.01 c/D, 28.0% ± 1.0%) with the VA (p = 0.0012) and CS (p < 0.001) differing significantly at the end of the treatment period. Our bioinformatics pipelines identified over 900 proteins with high confidence. ANOVA and pairwise comparisons of groups using the naïve control revealed 92 proteins affected by ORDX, 104 by OHT, and 88 regulated by DHED-derived E2. Analysis of DEPs in IPA revealed several dysregulated pathways associated with synaptogenesis and mitochondrial protein degradation and dysfunction. Lastly, we propose E2-responsive DEPs that may serve as potential preclinical biomarkers, such as apolipoprotein E and interphotoreceptor matrix proteoglycan 2. Conclusion: Our study combined behavioral assessments of vision and retinal proteomic mapping to reveal the neuroprotective effect of the topically applied DHED in ORDX OHT male BN rats. We identified for the first time numerous DEPs associated with the combined effects of estrogen-deprivation, OHT, and retina-targeted E2 treatments
Retroperitoneal Schwannoma: An Abnormal Presentation Mimicking a Pelvic Mass
No full textRAD 2025 Award Winning Posters & Oral Presentations, Poster Highlight: Texas College of Osteopathic Medicine - Case StudyBackground: A schwannoma is an encapsulated nerve sheath tumor originating from differentiated Schwann cells. They are preferentially localized to the head, neck and extremities with a minor occurrence of 1-3% in the retroperitoneal space. Schwannoma symptoms often are asymptomatic due to slow growth but can present with symptoms according to their location. We report a case of a 45-year-old female with a retroperitoneal schwannoma that mimicked an ovarian mass. Case Information: A 45-year-old female with a ten-year history of a right ovarian cyst presented with lower abdominal pain, early satiety, hematuria, low back pain and constipation. Transabdominal ultrasound showed right ovarian enlargement measuring 8.8 x 6.6 cm, described as heterogenous with loculations. Tumor markers indicated a low risk of malignancy. The patient was taken to the operating room for an exploratory laparotomy that revealed a large, firm posterior pelvic mass palpated in the retroperitoneal space. The cyst wall could not be completely dissected due to proximity to major vessels and nerve roots. The patient was referred to a neighboring academic institution because of the case complexity. She underwent repeat exploratory laparotomy and neuroplasty of the L5, S1 and S2 nerve roots. The L5 nerve root was ultimately sacrificed and the retroperitoneal mass was removed. Final pathology revealed a benign schwannoma. Conclusion: The diagnosis of a retroperitoneal schwannoma is often missed because of its rare occurrence, location, vague symptoms and resemblance to other tumors on varying imaging modalities. Due to low incidence and often delay in diagnosis, current management guidelines are limited and not well documented. Currently, histopathological exam after total surgical resection is the most reliable source for diagnosis. The patient in this case demonstrates the need for improvement in the preoperative evaluation and consideration of non-gynecologic differential diagnoses in the evaluation of a suspected pelvic mass
INVESTIGATING VARIATION IN HUMAN BODY COMPOSITION: A COMPARISON OF CT AND DEXA IMAGING MODALITIES
No full textAnthropologists have long recognized that differences in body composition influence how humans thermoregulate during exposure to different climatic conditions. Yet, research into the role of body composition in thermoregulation has been limited by a lack of methodological options for accurately quantifying different types of internal body tissues (i.e., bone, muscle, adipose). The development of medical imaging technologies such as computed tomography (CT) and dual energy x-ray absorptiometry (DEXA) has provided new approaches for accurately assessing the amount and distribution of various types of tissue within the body. However, the comparability of these two imaging modalities in assessing body composition has not been rigorously investigated. Accordingly, this project will employ matching sets of whole-body CT scans and whole-body DEXA scans collected from the same research subjects to evaluate the ability of each modality to quantify the absolute and relative amount of different tissue types. Initial results indicate that DEXA and CT return similar values for lean mass (DEXA = 29.94 kg, CT = 29.75 kg) differing by approximately 0.61%. In contrast, differences in fat mass values (DEXA = 10.57 kg, CT = 9.31 kg) are comparatively greater at 11.88%. Further research is needed to determine why the two modalities differ so substantially in their assessments of adiposity
Impact of the NFL Hip Drop Tackle Ban on Lower Extremity Injuries: A Comparative Analysis of Quadriceps, Hamstring, Knee, and Achilles Injuries
No full textPurpose: The NFL implemented a ban on the hip drop tackle before the 2024-2025 season due to concerns over lower extremity injuries. This study evaluates the impact of the ban on quadriceps, hamstring, knee, and Achilles injuries during the 2024 season compared to pre-ban seasons. Methods: Publicly available data from NFL injury reports and transactions from 2021-2024 were analyzed to identify players with isolated quadriceps, hamstring, knee, and Achilles injuries resulting in missed games. The 2024 season served as the index year post-ban, while the 2021-2023 seasons were averaged for pre-ban comparison. A Student’s t-test was performed using Jeffrey’s Amazing Statistics Program (JASP) to assess statistical significance. Results: Total quadriceps, hamstring, knee, and Achilles injuries were X in the pre-index seasons and Y in the index season. Knee injuries remained the most prevalent lower extremity injury pre- and post-ban. Achilles injuries showed a trend toward increased occurrence post-ban, with a p-value of 0.065, bordering statistical significance. Hamstring and quadriceps injuries demonstrated a nonsignificant decrease. Conclusions: Despite the hip drop tackle ban, knee injuries remained the most common, and Achilles injuries showed a potential increase. The findings suggest that additional years of post-ban data are needed to determine whether the rule change effectively reduces lower extremity injuries or alters injury mechanisms
A Case of Myasthenia Gravis in a Patient with Argyria
No full textBackground: Myasthenia Gravis is a rare autoimmune disorder that affects the nerve transmission to muscles and leads to muscle weakness¹. Myasthenia Gravis affects 10 to 20 people per 100,000 and more commonly occurs in women under 40 and men above 60¹. Case information: A 67 year old male with no past medical history presented to the emergency department complaining of generalized weakness, primarily of the upper extremities. Early that day, he experienced a fall and was unable to stand up due to weakness. He reported no falls prior to this episode and no previous episodes of weakness. He endorsed previous palpitations when experiencing stress. He had never seen a primary care physician and was not taking any medications, however he endorsed taking multiple supplements, including 20 years of elemental silver. Physical exam demonstrated a well appearing male in no acute distress with a blue-gray tint to his skin, especially prominent on the face and chest. Strength was ⅘ in the upper extremity and the remainder of the exam, including a neurologic exam was benign. There was no diplopia, ptosis, or lower extremity weakness. The patient endorsed he had argyria, a gray to blue discoloration of the skin caused by ingestion of colloidal silver that deposits in the skin after long term ingestion. Vitamin B12 was decreased (<159), C-reactive protein (CRP) was 15 mg/L (normal <10) and erythrocyte sedimentation rate (ESR) was 18 mm/HR (normal <15). Remaining labs were mostly benign with minor elevations in liver enzymes. On day three in the hospital, he endorsed returning upper extremity weakness, making it difficult to eat or ambulate. He endorsed difficulty clearing his throat, difficulty speaking, and worsening vision. Further examination now demonstrated ⅘ strength in the upper extremity, 5/5 strength of the lower extremity, and left eye ptosis all without noticeable fatigability with repeated motion. On day 5, he endorsed waxing and waning muscle weakness, worsening diplopia and new onset dry eyes. Labs showed acetylcholine receptor antibody levels of 131 nmol/L (positive is .05 or higher). Given the high specificity of this antibody, a diagnosis of Myasthenia Gravis was made and he was started on pyridostigmine and a prednisone taper. Weakness and ptosis improved upon starting pyridostigmine and prednisone. Conclusions: This case illustrates a unique case of Myasthenia Gravis with an arrhythmia in a patient with argyria. Long term ingestion of colloidal silver is most commonly associated with argyria as a side effect, but may also lead to renal, hepatic and neurologic dysfunction². While neurologic dysfunction has been documented in patients with long term ingestion of silver, no documentation in the literature is found of patients with Myasthenia Gravis and argyria
Assessing and Addressing the Unmet Needs of Patients with Systemic Lupus Erythematosus (SLE)
No full textSystemic Lupus Erythematosus (SLE) is a chronic autoimmune disease that significantly impacts patients' quality of life. Despite advancements in medical research, there remain substantial unmet needs in the management and care of SLE patients. This research project aims to identify and address these unmet needs through a comprehensive approach involving needs assessment, systematic review, and the development of educational materials. The project will begin with a detailed needs assessment to gather and analyze data on the unmet needs of SLE patients. This assessment will involve comparing existing needs assessments and their evaluation methods to create a tailored needs assessment for SLE patients. Data will be collected from UNTHSC pharmacy students and faculty, and the findings will be used to create an infographic that highlights the unmet needs in SLE patients. In parallel, a systematic review of current lupus research literature will be conducted to compare data and identify key issues faced by SLE patients. This review will inform the development of educational materials aimed at improving patient education and healthcare provider awareness. The educational materials will include patient education handouts, verbal counseling tips, and other resources to help patients understand SLE and encourage healthcare providers to use uniform patient education materials. The final products of this project will include a comprehensive needs assessment report and a set of educational materials. These products will be disseminated through UNTHSC and HSC Health to raise awareness and improve the quality of care for SLE patients. By integrating principles of diversity and inclusivity, this project aims to make a meaningful contribution to the organization and enhance the care provided to SLE patients. IRB Number This study has been submitted for IRB approval and is pending review. Only the results of the systematic review and the educational material will be shared with this poster
Presentations of Cutaneous Disease in Various Skin Pigmentations: Keloids
No full textIntroduction: Keloids are benign, firm nodules resulting from excessive scar formation, typically following trauma, but they can also arise spontaneously. They commonly affect areas like the chest, shoulders, back, cheeks, and earlobes. Their growth exceeds the boundaries of the original injury. Keloids can cause discomfort, pruritus, or cosmetic concerns. While they are more prevalent in individuals with darker skin tones, they occur across all age groups and skin types. Differentiating keloids from conditions such as hypertrophic scars, dermatofibromas, acrochordons, inflamed nevi, cysts, and lipomas is crucial for proper diagnosis and management. This review highlights the diverse clinical presentations of keloids across various Fitzpatrick skin types. Case Presentation: We present a series of cases demonstrating the diverse presentations of keloids across various Fitzpatrick skin types. The first case involves a 16-year-old male with Fitzpatrick skin type I, presenting with pink, shiny, raised keloids on the shoulders, back, and chest secondary to cystic acne. The second case shows a woman with Fitzpatrick II skin type, presenting with a biopsy-confirmed keloid, described as a firm, pink, linear, well-demarcated raised plaque without adnexal structures, resulting from a previous surgery. The third case features a 17-year-old male with Fitzpatrick III skin type, displaying shiny, pink-to-purple keloids and active cystic acne scars on his chest, shoulders, and back. The fourth case is a 64-year-old female with Fitzpatrick IV skin type, presenting with smooth, linear keloids on her chest resulting from bypass surgery. The fifth case involves a 55-year-old female with Fitzpatrick V skin type, exhibiting linear keloids on her back and smaller plaques on her arm, all darker than her baseline skin tone. The final case is a 73-year-old male with Fitzpatrick VI skin type, who developed spontaneous, hyperpigmented linear keloids across his shoulders, arms, and back. Learning Points: Keloids present differently across Fitzpatrick skin types, often appearing pink or reddish in lighter tones and hyperpigmented in darker tones, highlighting the importance of recognizing these variations for accurate diagnosis. Despite these differences, keloids share common features, including smooth, firm nodules that extend beyond the initial trauma and lack adnexal structures, which help differentiate them from other common conditions such as hypertrophic scars, dermatofibromas, acrochordons, inflamed nevi, cysts, and lipomas. Effective diagnosis and management depend on understanding these variations and employing targeted interventions such as intralesional steroids or surgical excision