Ann Marie Stephenson Thomas, DO, MBA in Baltimore: Gastroenterology with a Business-Focused Practice Model
Ann Marie Stephenson Thomas operates a gastroenterology practice in Baltimore that distinguishes itself through her dual credentials in medicine and MBA training, which shapes how the practice approaches both clinical care and the business side of scheduling, insurance, and patient access. As a DO (Doctor of Osteopathic Medicine) rather than an MD, she brings training in manipulative medicine alongside conventional gastroenterology, though her primary focus remains diagnostic and therapeutic endoscopy and gastrointestinal conditions. The practice sees both established patients and new referrals in Baltimore, with an emphasis on procedural gastroenterology.
What the practice handles
Stephenson Thomas's scope covers the full range of gastroenterology: upper endoscopy, colonoscopy, management of reflux disease, peptic ulcer disease, and inflammatory bowel conditions. She performs both diagnostic and therapeutic procedures, including biopsies and polyp removal during colonoscopy. The practice accepts referrals from primary care providers and specialists across Baltimore and manages both routine screening cases and complex diagnostic work. Because her training includes both osteopathic medicine and an MBA, she is comfortable discussing how insurance coverage, procedure timing, and financial planning affect your care pathway, not just the clinical details.
Services and typical costs
Gastroenterology procedures in Baltimore vary significantly by insurance plan and facility. Colonoscopy screening covered by insurance typically carries a patient responsibility of $0 to $500 depending on your plan's deductible and out-of-pocket status. Upper endoscopy runs $500 to $1,500 out-of-pocket if uninsured; insurance-covered procedures range from $0 to $400 in patient responsibility. For established patients with chronic conditions like reflux or IBD, office visits and medication management are usually $150 to $250 per visit. Confirm your specific insurance coverage before booking, as facility fees and anesthesia charges vary independently of the physician fee.
How Stephenson Thomas compares to other Baltimore gastroenterologists
Baltimore has a mix of private practices, hospital-affiliated gastroenterology groups, and academic medical centers. University of Maryland Medical Center and Johns Hopkins Hospital both employ gastroenterologists and offer faster access to imaging and subspecialty support if you have complex disease. Private practices like Stephenson Thomas's typically offer more flexible scheduling and a more direct relationship with one physician across multiple visits. Choose an academic center if you need rapid diagnosis of a complicated case or if your condition may need a second opinion from multiple specialists in one system; choose a private practice if you value continuity with one provider and straightforward scheduling without a large hospital administrative layer. Hospital-affiliated groups fall in the middle, offering some of the convenience of private practice with access to in-house imaging and specialty backup.
Who suits this practice and who does not
New patients should be comfortable with a straightforward, clinically detailed approach. The MBA component of her background means she is direct about insurance pre-authorization, cost discussions, and the timing of procedures relative to your coverage calendar. This suits patients who want to understand the business and financial framework of their care alongside the medical facts. Patients with complex inflammatory bowel disease, refractory reflux, or diagnostic uncertainty benefit from her procedural expertise. Patients seeking only referral for a single procedure without ongoing relationship management might find a hospital system's pool of providers more flexible. Patients without insurance should ask about cash pricing at the time of booking, as many gastroenterology offices negotiate self-pay rates different from the insurance fee schedule.
What the first visit involves
New-patient appointments typically begin with a detailed history focusing on GI symptoms, previous procedures, family history of colon cancer or IBD, and current medications, especially aspirin or anticoagulants. Stephenson Thomas will perform an abdominal exam and review any previous imaging or endoscopy reports you bring. Most first visits do not include a procedure; the appointment establishes the clinical picture and schedules a procedure for a separate date if appropriate. You will need to bring your insurance card and a photo ID. Pre-procedure paperwork must be completed at least 3 to 5 business days before any endoscopy.
Hours, parking, and how to schedule
Specific office hours and parking details should be confirmed directly with the practice at the time of booking, as gastroenterology office schedules often vary by procedure load and provider availability. Call to verify current hours before traveling. Most Baltimore gastroenterology practices offer morning and early-afternoon appointment slots to accommodate fasting requirements for procedures. Parking options depend on the office location; ask when you call whether street parking, a lot, or valet is available.
Stephenson Thomas fills a distinct niche for Baltimore patients who value procedural gastroenterology from a provider trained to discuss insurance pathways and cost as openly as clinical options.
