Via Research Recognition Day 2024 VCOM-Carolinas

Clinical Case-Based Reports

Salmonella -Associated Multifocal Alimentary Canal Infarction Caleb Bryson 1 , OMS-III, Chirag Lodha 1 , OMS-III, Stanley D. Miller, MD 1 VCOM Carolinas, Internal Medicine, Spartanburg, South Carolina Introduction Conclusions

Table 1 . Characteristics and workup of Mesenteric Venous Thrombosis

• Acute Mesenteric Ischemia (AMI) occurs whenever perfusion to the intestines by the mesenteric vasculature is suddenly impaired; this vascular compromise will result in progressive intestinal ischemia and subsequent infarction if adequate perfusion to the affected area is not restored [1]. • AMI is a life-threatening intestinal emergency and high mortality rates ranging between 50 – 100% in are commonly seen in advanced cases [2], furthermore in recent years the incidence of AMI is believed to have increased and now accounts for up to 10% of cases of “acute abdomen” in patients greater than 70 years old [2]. • The initial presentation of AMI is dependent on the underlying cause, but many cases begin with nonspecific abdominal symptoms like nausea, vomiting, tenderness to palpation, as well as pain patterns and abdominal distention that may closely resemble more common abdominal pathologies like appendicitis, severe constipation, peptic ulcer disease, or bowel obstructions [1]. • The clinical presentation of AMI is often variable ; In cases of AMI due to arterial occlusion patients commonly report abdominal pain that is extremely severe, out of proportion with physical exam findings, sudden in onset, and constant [2]. • This is in contrast to AMI due to venous thrombosis which often presents with patients reporting their initial symptoms being progressively worsening, colicky midabdominal pain that becomes more intense and constant over a variable period of hours to days. [2] • There are many risk factors associated with an increased risk of AMI with conditions like coronary artery disease, peripheral artery disease, atrial fibrillation, arterial hypertension, congestive heart failure, and inherited and acquired hypercoagulable states being notable examples [1]. • The pathogenesis of conditions resulting from an embolic or thrombotic process often centers around the concept of Virchow’s Triad ; the 3 components of this triad are as follows: Alterations in blood flow (i.e.: stasis), vascular endothelial injury, and a hypercoagulable state (either inherited or acquired) [3]. • Malignancy is associated with alterations in all 3 portions of Virchow’s Triad. [4] • AMI due to venous thrombosis also has been shown to exhibit a unique pattern of pathologic changes that help distinguish it from AMI due to arterial occlusion; affected tissue areas of bowel infarction due to MVT show patchy discontinuous areas of “dusky cyanosis that gradually fade into adjacent areas of normal tissue", whereas cases where bowel infarction is secondary to acute arterial occlusion exhibit continuous areas of infarction and have sharply demarcated transition points observed between the affected area and unaffected surrounding tissues [5]. • 67-year-old female presented to the Emergency Department several times over subsequent days with nausea, vomiting, diarrhea, and progressively worsening abdominal pain. • Conservative therapies that were effective during her initial visits began to fail. • The patient had a positive result for Salmonella spp. on a stool PCR assay, an increasing leukocytosis, and the presence of several other worrisome laboratory abnormalities. • Despite appropriate antibiotics and aggressive fluid resuscitation efforts Report of Case the patient’s abdominal pain continued to worsen and she acutely decompensated, necessitating an emergent exploratory laparotomy. • The patient was found to have several areas of infarction present across multiple vascular planes, including her esophagus, stomach, duodenum, proximal jejunum, and right colon. • A metastatic neuroendocrine tumor of GI origin was found, with an unknown primary location. • Resected tissue histology and pathology showed findings consistent with an ischemic process secondary to venous thrombosis.

• Venous thrombosis of mesenteric vessels and other vascular planes of the alimentary canal is often insidious in its presentation and poses a unique diagnostic challenge to clinicians. • The patient's septic state also likely contributed to widespread tissue ischemia. • Due to the patient's allergy to IV contrast and inability to receive allergy prophylaxis, the diagnostic modality of choice was not performed, leading to a delay in diagnosis. • Alternative imaging modalities must be considered an emergent situation's such as acute mesenteric ischemia. • Further research prospects include investigating clinical biomarkers for AMI. • Providers must ensure a high level of suspicion of AMI in older populations due to its rising prevalence in this demographic.

Mesenteric Venous Thrombosis: Common Clinical Presentations & Indicated Workup

Symptoms

Signs

Risk Factors

Early • Subacute, Insidious Onset of Colicky (Cramping) Abdominal Pain • Progressive Symptom Worsening • Concomitant Thrombotic Event (EX: DVT, PE, DIC, Trousseau Syndrome,

• D – Dimer (> 0.9) • Elevated Lactate Levels (D / L Lactate and Lactate Dehydrogenase) • Elevated Amylase (>150 but <1000: Above Normal but less than Pancreatitis ranges) • +- Doppler Flow Changes in Mesenteric Vasculature ()

• Hypercoagulable State

Onset ~6 days

(Ex: Inherited & Acquired Thrombophilia's,

Malignancy, DIC, etc.) • Prior Thrombotic Event

(EX: DVT, PE, DIC, Trousseau Syndrome,

etc.) • Recent Abdominal Infection / Inflammatory Process (Ex: Pancreatitis, Salmonellosis, Gastroenteritis, etc.)

etc.) Late • ***Pain out of Proportion*** • Peritoneal Signs • Signs of Sepsis

~14 days

Reference: #X

Clinical Presentation Highly Suspicious for AMI EX: AMI Risk Factors + Concerning Objective Findings

Hemodynamically Unstable or Signs of Sepsis?

Yes

References

No

Resuscitate and / or Emergent Laparotomy - IV Fluids - Remove Inciting Factors

CT Unavailable, or not Feasible? (i.e.: Contraindicated)

Obtain Imaging

Alternate Imaging

- Empiric Antibiotics - Consider Systemic Anticoagulation And/or Exploratory Laparotomy

Consider CT Prophylaxis

Abdominal CT with Contrast

MR Biphasic Angiography/ Venography Or, less desirably Doppler Ultrasound*

If Non-diagnostic but Clinical Suspicion for AMI remains High?

Biphasic CTA / CTV

Negative for MVT

Positive for MVT

Note: * Doppler Ultrasound is a less desirable alternative but can be considered for larger thrombi if MRA/MRV is unavailable)

Anticoagulation or Thrombectomy

Anticoagulation or Consider other Diagnosis

Acknowledgements

Special thanks to Spartanburg Regional Medical Center

Table 2 . Patient coagulation labs

Ug/mL FEU ( Age Adjusted Cutoff)

D – Dimer

5.39 (H) 20.5 (H) 1.8 (L)

< 0.670

PT

12.7 – 15.1 seconds

INR

2.0 – 3.0

81

2024 Research Recognition Day