Louisiana Research Day Program Book 2025

Case Studies: Section 1

Case Studies: Section 1

Stephanie Hilton, OMS-III 1 ; Stephen DiGiuseppe, PhD 2 VCOM-Louisiana; Infectious Disease, St. Francis Medical Center, Monroe, LA 90 A CASE OF STREPTOCOCCUS CANIS ASSOCIATED SEPSIS IN A DOG OWNER

Steven Sasser, OMS-III Saint Francis Medical Center Department of Surgery 91 PHEOCHROMOCYTOMA: SURGICAL TREATMENT AND MANAGING ASSOCIATED HYPERTENSION

Context/Impact: This is a case of sepsis due to an infection with Streptococcus canis (S. canis) in a dog owner with a history of breast cancer, lymphedema, and a documented allergy to cephalosporin antibiotics. Documented human cases of S. canis infections are rare. Patient factors such as immunocompromise, advancing age and other comorbidities appear to play a role in the acquisition of clinical disease from S. canis, and many cases reported share a common thread of exposure to dogs. Report of Case: A 73-year old female with a past medical history of high blood pressure, dyslipidemia, hypothyroidism, breast cancer with bilateral mastectomy and right arm lymphedema, presented to the emergency department (ED) with fever, chills, cough, and nasal congestion. Lab results revealed leukocytosis with a high neutrophilic predominance, hypoxia, and elevated troponins. Diagnostic imaging suggested pulmonary edema. Two sets of blood cultures were obtained. The patient was diagnosed with sepsis with acute hypoxic respiratory failure, admitted, and started on empiric antibiotic treatment with azithromycin. Subsequent exacerbation of her hypoxemia and

leukocytosis resulted in transfer to the critical care unit (CCU) for more intensive hemodynamic monitoring, high flow oxygen therapy, and a central venous line for improved venous access. Identification of the S. canis in her blood cultures prompted modification of antibiotic therapy to penicillin G. The patient spent nine days in the CCU before she was stabilized enough to move to a step down unit. Due to her elevated troponins at admission, she received a left heart catheterization showing no indication of myocardial infarction and suggested demand ischemia related to her hypoxia. A transesophageal echocardiogram (TEE) found no evidence of infective endocarditis. Repeat blood cultures showed no growth in the sample. The patient required oxygen therapy throughout her admission, receiving thirteen days of care before discharge to inpatient rehabilitation where she completed her antibiotics course totaling 13 days of antibiotic therapy with penicillin G. Comments/Conclusion: Patients with preexisting comorbidities, children under five years, and adults older than 65 may be at greater risk for infection with S. canis. Among conditions that increase risk are history of

malignancy, diabetes mellitus, and lymphatic insufficiency. Confirmed cases of S. canis in the literature often cite exposure to a dog, but no physical injury from the animal suggesting contact to a carrier animal’s bodily fluids may be sufficient to cause infection in a human either through skin wounds, burns, abrasions, and micro abrasions, or due to venous or lymphatic insufficiency. This patient reported contact with a dog that lived in her home and confirmed exposure to the animal’s saliva by the dog licking her on occasion, but no bite injury. No inquiry regarding the presence of a dog in this patient’s home was made until S. canis was identified in her blood cultures. The prevalence of companion animals in homes worldwide should direct clinicians to conduct comprehensive history taking that includes gathering information about animal exposures, including exposure to animals within the home. This practice can assist in more swift identification of potential sources of infection and guide discharge instructions to patients to prevent future infections.

Context: A 73-year-old female was referred for surgical removal of a right pheochromocytoma after years of multi-drug resistant hypertension. Due to possible years of growth, the mass was nearing invasion through the wall of the inferior vena cava causing hemorrhage through mass effect. Report: The patient is a well-established patient with her primary care provider (PCP) that has had hypertension since her early 30s requiring hypertensive medications. In recent years, her PCP has increased medication dosages as well as added two more antihypertensive medications while continuing the established diagnosis of drug resistant hypertension, but no other labs or imaging were ordered to discover the cause. The patient developed symptoms of an upper respiratory infection and received a CT of her chest which showed an incidental finding of a mass on the upper pole of her right kidney. An abdominal CT was ordered to further investigate the size of the mass, and serum and urine metanephrines were ordered to confirm the diagnosis of a pheochromocytoma. Imaging showed a 4 cm x 4 cm mass in close approximation to the IVC, and labs showed

a serum norepinephrine of 303 ng/mL. She was then referred to general surgery for urgent removal of the mass of the right adrenal gland. This required two weeks of preoperative blood pressure control. The standard of care suggests using phenoxybenzamine for blood pressure control, but due to financial constraints, she was placed on doxazosin and labetalol. After the time frame, the surgery was completed without complication. The mass had just begun to invade into the most superficial layer of the IVC but not through the tunica intima allowing it to be resected carefully without hemorrhage. She was then monitored in the hospital for three days to ensure proper blood pressure control while also tailoring her medications to her needs. Currently, she is on a low dose of a single anti hypertensive medication and still follows up with her PCP as recommended. Conclusion: Having a high clinical suspicion and investigating for secondary causes of drug resistant hypertension is necessary for improved patient outcomes. Without the incidental finding on her chest CT, the mass would have likely invaded into the IVC leading to deadly hemorrhage. Once the appropriate imaging and

labs were ordered, her results followed textbook results for a diagnosis of pheochromocytoma. Her case reinforces the mission of osteopathic physicians to treat the underlying illness rather than treating the symptoms causing the issues.

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105 2025 Research Recognition Day