United States

Introduction: Total Hip Arthroplasty (THA) is one of the most common orthopedic procedures performed in the United States. With nearly 500,000 cases performed annually, the success rate has been estimated to be around 90-95%. Known complications from THA are classified into early or late stages. The association between arterial thrombotic events such as ischemic colitis (IC) and acute limb ischemia following THA has not been highly reported. 

Case Report: 62-year-old male nine days status post right THA presented to ED for altered mental status. On arrival, BP was 95/57, HR 104, and O2 sat 88% on 10L NC. The bilateral lower extremities were swollen and cool to touch with absent DP pulses. The abdomen was distended with diffuse tenderness. CT abdomen/pelvis was concerning, and the decision to proceed with exploratory laparotomy was made. Upon entry into the peritoneum, foul-smelling, purulent fluid was present. It was evident that the patient had an ischemic left colon in the distribution of the IMA with sparing of the rectum. The ischemic colon was resected, and an ostomy was brought out. Despite aggressive resuscitation attempts, the patient continued to worsen and remained intubated. On postoperative day 7, due to severe acidosis and deteriorating multiorgan failure, the patient&#39;s family opted to withdraw care. 

Discussion: To our knowledge, there has been only one published report of mesenteric ischemia following THA. The standard of care following THA to prevent thromboembolism has changed over the last ten years from Warfarin to direct oral anticoagulants (DOAC), with recent literature describing the beneficial efficacy of monotherapy with aspirin. Due to life-threatening complications, strict compliance with VTE prophylaxis is necessary for all post-operative patients.

Conclusion: With THA volume increasing yearly, we aim to emphasize the importance of recognizing these rare and potentially devastating postoperative vascular complications.


2022 AMA Research Challenge

Multiple Ischemic Events Following Total Hip Arthroplasty

Welcome to the largest national, multi-specialty research event **featuring research from 750 medical students, residents and fellows, and international medical graduates.**


#### Event Details
The 2022 American Medical Association Research Challenge includes a poster symposium hall and a semifinals hall with the top scored research. Log in at any time throughout the event to:
* **View posters and presentations** on a variety of topics and specialties
* **Score posters in the semifinals** to help decide the top five finalists (AMA member exclusive opportunity)
* **Connect with participants** and provide feedback to help advance their research

At the conclusion of this event, the AMA will announce the top five finalists who will advance to the AMA Research Challenge finals, present their research to an elite panel of judges and compete to win a $10,000 grand prize sponsored by Laurel Road.
 

#### Attend Live Forums
**Oct. 20, 6 — 7 p.m. Central**
 **How to plan a career in academic medicine** 
 Learn how to plan a career in academic medicine and get your questions answered. [Access Here](https://underline.io/events/363/lounge)
 
 **Speakers**
![](https://assets.underline.io/uploads/markdown_image/1/image/d5adb133dfc58eb0a6d469e9cedcd5d4.jpg)
Ricardo Correa, MD, EdD
![](https://assets.underline.io/uploads/markdown_image/1/image/5f9437ab87861538bf02b9ca7c0d926e.jpg)
Stuart M. Greenstein, MD
![](https://assets.underline.io/uploads/markdown_image/1/image/05b1b637c99286d558c371f8e8b185ce.jpg)
Stephanie Strohbeen, MD
 
 **Oct. 22, 11 a.m. — Noon Central**
 **How to get published**
 Learn tips to get your research published and get your questions answered. [Access Here](https://underline.io/events/363/lounge)
 
 **Speakers**
![](https://assets.underline.io/uploads/markdown_image/1/image/8ce6235e957d31cb5e6f9097cc6f6972.jpg)
Jessica Li, MD/PhD Candidate
![](https://assets.underline.io/uploads/markdown_image/1/image/9950ef2e0237f54cb3d8280334d42491.jpg)
Charles Lopresto, DO

### Sponsor
AMA would like to thank Laurel Road for sponsoring a $10,000 grand prize for the winner of the AMA Research Challenge. Laurel Road is not involved in the judging or scoring process to select the winner. The winner will be announced on Dec. 7 during the AMA Research Challenge finals. Payment of the grand prize will be directly from Laurel Road. See the AMA Research Challenge Official Rules for terms and conditions.

![](https://assets.underline.io/uploads/markdown_image/1/image/611e331d4a0eba0920f240cfc04b4d77.png)

**There is no registration fee for this event! **

Register to explore research in a variety of topics. AMA members get exclusive access to score posters in the semifinals.

**Please use the link below to register for free if you have not already done so:**

https://www.ama-assn.org/about/events/ama-research-challenge

Registration Is Required

Welcome to the largest national, multi-specialty research event featuring research from 750 medical students, residents and fellows, and international medical graduates.


Introduction: Total Hip Arthroplasty (THA) is one of the most common orthopedic procedures performed in the United States. With nearly 500,000 cases performed annually, the success rate has been estimated to be around 90-95%. Known complications from THA are classified into early or late stages. The association between arterial thrombotic events such as ischemic colitis (IC) and acute limb ischemia following THA has not been highly reported. 

Case Report: 62-year-old male nine days status post right THA presented to ED for altered mental status. On arrival, BP was 95/57, HR 104, and O2 sat 88% on 10L NC. The bilateral lower extremities were swollen and cool to touch with absent DP pulses. The abdomen was distended with diffuse tenderness. CT abdomen/pelvis was concerning, and the decision to proceed with exploratory laparotomy was made. Upon entry into the peritoneum, foul-smelling, purulent fluid was present. It was evident that the patient had an ischemic left colon in the distribution of the IMA with sparing of the rectum. The ischemic colon was resected, and an ostomy was brought out. Despite aggressive resuscitation attempts, the patient continued to worsen and remained intubated. On postoperative day 7, due to severe acidosis and deteriorating multiorgan failure, the patient's family opted to withdraw care. 

Discussion: To our knowledge, there has been only one published report of mesenteric ischemia following THA. The standard of care following THA to prevent thromboembolism has changed over the last ten years from Warfarin to direct oral anticoagulants (DOAC), with recent literature describing the beneficial efficacy of monotherapy with aspirin. Due to life-threatening complications, strict compliance with VTE prophylaxis is necessary for all post-operative patients.

Conclusion: With THA volume increasing yearly, we aim to emphasize the importance of recognizing these rare and potentially devastating postoperative vascular complications.


poster

Novel Surgical Technique to Repair Pediatric Tibial Tubercle Avulsion Fracture,
No Need for Hardware or Casting

Background: 
Lacrimal gland tumors are a rare malignancy with an incidence of about 1 per 1 million people. Epithelial tumors are the most common form representing 50-60% of all lacrimal gland tumors with carcinoma ex pleomorphic adenoma (CEPA) constituting 10% of the epithelial tumors. CEPA is a malignant tumor that arises from benign pleomorphic adenomas. Clinical features include rapid growth causing eyelid and orbital protrusion often accompanied by pain. Mean survival after diagnosis is three years. CEPA may progress to intracranial spreading along with possible metastatic malignancy to the lung, chest, and bone. These malignancies are treated aggressively with a combination of surgical resection, chemotherapy, and radiation. 

Case Presentation: 
A 79-year-old male with a history of right eye exenteration after a childhood injury initially presented to his PCP with a mass on his right lower eyelid. A biopsy was obtained, and pathological results were initially suspicious for squamous cell carcinoma. He was referred to ENT who excised the lesion with intraoperative pathology confirming a negative margin. Pathology results from the excision were consistent with a 3 cm high-grade carcinoma ex pleomorphic adenoma of the lacrimal gland. Three weeks after resection, PET/CT scan showed local recurrence at the inferior resection margin and metastatic disease in a 1B cervical lymph node. The patient underwent combination chemoradiation therapy with complete regression confirmed by PET/CT. Nine months after completing chemoradiation, repeat PET/CT showed two new lung nodules concerning for metastatic disease. The patient did not wish to undergo further testing or treatment and decided to transition to comfort care only. 

Discussion: 
CEPA is an incredibly rare and aggressive tumor about which little is known regarding the preceding oncogenic events in the literature, indicating the need for further research to improve treatments.

Carcinoma Ex Pleomorphic Adenoma: An Extremely Rare Tumor of the Lacrimal Gland

Aggressive natural killer cell leukemia (ANKL) is a rare neoplastic malignancy, especially in pediatric populations with very few cases reported in the literature. It commonly presents with a rapidly declining clinical course and has a median survival of two months. We report the case of a 15-year-old female who presented with fever, hepatosplenomegaly, hemophagocytosis, and disseminated intravascular coagulation (DIC). The patient was ultimately diagnosed with ANKL but died after developing multiorgan failure and DIC prior to the initiation of any treatment. In this case report, we review and discuss the literature concerning the diagnosis and treatment of ANKL in pediatric patients.

A Case Report on Aggressive Natural Killer Cell Leukemia in a Pediatric Patient 

A Sugar of 4: An Unlikely Presentation of Glycogen Storage Disease


Acute liver failure (ALF) is a dynamic clinical condition manifested either by an abrupt or indolent onset of a liver-based coagulopathy and biochemical evidence of hepatocellular injury resulting from rapid deterioration in liver cell function. Acetaminophen overdose is the most common cause of ALF in Western countries and its incidence appears to be increasing. Most acetaminophen overdose patients recover with early N-acetylcysteine (NAC) therapy and supportive care, but regulatory actions are needed to prevent future cases. However, we must consider alternative causes of hepatitis which include HBV infection (7%), autoimmune hepatitis (5%), ischemic hepatitis (4%), and various other causes (5%). We present a 16 y.o. who presented in Acute Liver Injury (ALI) with transaminitis progressing to ALF (INR 2.5, NH4 119 umol/L, ALT 2,812/AST 6,222 U/L). In this case presentation, we aim to highlight the importance of obtaining a thorough history and including the practice of excluding alternative causes. While our patient denied intentionally overdosing on acetaminophen, an acetaminophen level of 24 mcg/mL at ~24 hours is significant. Without the concomitant acute EBV hepatitis (EBV PCR pos, EBV Capsid Ag IgM 96.4, EBV IgG neg), she likely would have experienced less severe liver injury without progression to acute liver failure. The appropriate initiation of intravenous N-acetylcysteine and fomepizole likely played a critical role in halting the progression by blocking further metabolism of acetaminophen by CYP2E1. Perhaps most importantly in delayed presentations, fomepizole inhibits c-Jun-N-terminal Kinase (JNK) which mitigates liver inflammatory responses. NAC may help other causes of ALI/ALF not caused by acetaminophen.

Accidental Acetaminophen Overdose?

Abstract Title: An Interesting Presentation of Cutaneous Mastocytoma
Background
Mastocytosis is a clonal proliferative disorder in which mast cells accumulate in various organs, most commonly the skin. Mast cell degranulation releases inflammatory mediators, which induce edema, pain, and pruritus. 

Case Presentation
A previously healthy, two-month-old female presented to the emergency department (ED) for what appeared to be a blistering skin infection. Prior to arrival, the patient experienced a transient episode of “beet red” flushing, cheek swelling, and diarrhea. Immediately after, the area on the right ankle was indurated and violaceous with erythematous borders.

The patient was born via vaginal delivery at 39 weeks. Of note, the patient’s mother has a history of genital herpes simplex virus (HSV) and took valacyclovir one month prior to delivery. She reported no active lesions at the time of delivery. 

In the ED, physical exam revealed an approximately two-centimeter ovoid area of mild hyperpigmentation with an erythematous border on the lateral aspect of the right ankle. Overlying this area were multiple vesicles in a cluster, the largest approximately six millimeters in diameter.

HSV and general wound culture swabs of the ankle, as well as blood cultures, were collected. A punch biopsy of the lesion was sent for pathological review, which ruled out cutaneous HSV infection. Additional staining was performed to evaluate for Langerhans’ cell histiocytosis and mastocytosis. Histologic features and immunophenotype confirmed the diagnosis of mastocytosis. 

Discussion
Given the maternal history and concern for potentially fatal complications, the thought was that the patient could have HSV infection. When HSV infection was suspected, a Tzanck smear could have been an alternative diagnostic strategy; however, the sensitivity and accuracy can depend on the interpreter and disease incidence. Because of the relatively low incidence in this geographic region, it is likely that a negative Tzanck smear would have required confirmatory testing via punch biopsy.

Another strategy could have been a wound swab with viral polymerase chain reaction for HSV, a highly sensitive and specific test, but the involved hospital is not large enough to make these assays economically viable. Ultimately, performing a skin biopsy allowed a rapid and definitive diagnosis of this patient.

An Interesting Presentation of Cutaneous Mastocytoma

Hemifacial Spasms in the Pediatric Population: A Case Series

Isolated Upper Gastrointestinal Findings in Pediatric Patient Found to Have Crohn’s Disease

Introduction

Multisystem inflammatory syndrome in children rarely involves severe coronary dilation, multiple readmissions, or occurrence after COVID-19 vaccination. We describe the case of a boy aged 5 years with all three of these unusual features.

Case Presentation

A previously healthy 5-year-old male was hospitalized with fever for 4 days, sore throat, myalgias, abdominal pain, conjunctivitis, and rash. Symptom onset was 56 days after acute COVID-19 illness and 16 days after receiving one dose of the Pfizer COVID-19 vaccine. Workup was notable for elevated inflammatory markers, mildly elevated cardiac biomarkers with evidence of SARS-CoV-2 infection, including both SARS-COV2-PCR and anti-nucleocapsid antibody. Patient was diagnosed with MIS-C with Kawasaki features, and demonstrated clinical improvement after treatment with IVIG, steroids and aspirin. Echocardiography during the initial hospitalization was reassuring. On day 7 of MIS-C illness, the patient was discharged with low dose aspirin and prednisone.

A day after completing his course of prednisone, on day 10 of MIS-C illness, patient presented to the emergency room again with fever, fatigue, rash, conjunctivitis, and dry, cracked lips. Labs were notable for thrombocytosis, leukocytosis, and elevated CRP, ESR, and d-dimer. He was diagnosed with recrudescence of MIS-C with features of Kawasaki disease. He was started on IV methylprednisolone 1 mg/kg, and low dose aspirin. Echocardiography on day 11 was significant for newly dilated coronary arteries with no aneurysms, and patient was promptly started on his second course of IVIG, from which he remained afebrile. Repeat echocardiogram was not notable for any changes. On day 14, patient was discharged with a prednisolone taper and low dose aspirin. Until day 20 of illness, he took 1 mg/kg of prednisolone twice daily.

On day 21, patient’s prednisolone was tapered to 1 mg/kg once daily, and he presented with fevers, dry cracked lips, conjunctivitis and abdominal pain on day 23. Inflammatory markers had elevated since previous discharge. Echocardiography was significant for severe dilation to his coronary arteries, especially his right coronary artery (RCA) (4.5 mm) and left anterior descending artery (LAD) (6.7 mm). He began treatment for refractory MIS-C and was started on infliximab and methylprednisolone. He was also given enoxaparin for his coronary artery dilation. On day 25, echocardiography continued to show severe coronary artery dilation, most significant with the LAD. His inflammatory markers and clinical course improved, and on day 28, repeat echocardiography showed no significant change. Patient was discharged on enoxaparin, daily aspirin, and a 30-day steroid taper. He remains asymptomatic, and most recent echocardiogram remains stable with slight improvement. A month after his most recent discharge, his inflammatory markers were found to be increasing, and his steroid taper was adjusted accordingly.

Discussion:

Our patient was admitted three times for MIS-C refractory to initial treatment with intravenous immunoglobulin, corticosteroids and anti-inflammatory agents. Readmission for MIS-C is not common. Among the 457 cases of MIS-C at our institution, this is the only patient to require 2 readmissions for MIS-C. He also developed giant coronary aneurysms. A diagnosis of MIS-C after COVID-19 vaccination is rare. In a study of vaccination in the United States, only one case occurs per million vaccinated children between the ages of 12-20 were noted to have MIS-C after vaccination. Whether or not the patient should receive his second Pfizer vaccine was questioned. Given current CDC guidelines, no future COVID-19 vaccinations are planned until the patient has at least made a complete recovery from his cardiac complications.

Premium content

Multiple Ischemic Events Following Total Hip Arthroplasty

Next from 2022 AMA Research Challenge

Novel Surgical Technique to Repair Pediatric Tibial Tubercle Avulsion Fracture, No Need for Hardware or Casting

Similar lecture

Current Trends In Operative Intervention Of Mallet FInger Injuries