In a 43‑year‑old woman on postoperative day 9 after vaginal hysterectomy, with a kidney (and likely pancreas) transplant and on anticoagulation, who presents with acute right‑upper‑quadrant to mid‑abdominal pain and guarding, what are the appropriate differential diagnoses and immediate work‑up?

Acute Right Upper Quadrant to Mid-Abdominal Pain Post-Vaginal Hysterectomy in Anticoagulated Transplant Patient

In this 43-year-old woman on postoperative day 9 after vaginal hysterectomy with kidney transplant and anticoagulation presenting with acute RUQ-to-mid-abdominal pain and guarding, obtain immediate CT abdomen and pelvis with IV contrast to evaluate for postoperative hemorrhage, abscess, or biliary pathology—this is the single most appropriate diagnostic test for this clinical scenario. 1

Differential Diagnosis

High-Priority Life-Threatening Conditions

Postoperative hemorrhage/retroperitoneal hematoma:

• Retroperitoneal hematoma is a recognized complication of vaginal hysterectomy, particularly in anticoagulated patients, and can present with acute abdominal pain and hemodynamic instability even days after surgery 2
• The combination of anticoagulation and recent pelvic surgery creates substantial bleeding risk, with hemorrhage being a documented complication requiring transfusion in hysterectomy patients 3
• Zone III retroperitoneal hematomas can extend into the upper abdomen, explaining the RUQ-to-mid-quadrant pain distribution 2

Postoperative abscess:

• Infectious complications are the most common after hysterectomy, occurring in 10.5-13% of cases, with vaginal hysterectomy carrying a 13% infection rate 3
• Postoperative fever with abdominal pain in the setting of recent bowel manipulation or surgery is primarily concerning for abscess formation and warrants cross-sectional imaging 1
• Immunosuppression from transplant medications significantly increases infection risk in this population 4

Biliary pathology (acute cholecystitis):

• Acute cholecystitis is the primary diagnostic consideration in patients presenting with RUQ pain 1
• Immunosuppressed transplant patients have altered inflammatory responses that can mask typical presentations 4
• Guarding in the RUQ specifically raises concern for gallbladder pathology 1

Moderate-Priority Surgical Complications

Bowel injury/anastomotic leak:

• Gastrointestinal tract injury occurs in 0.1-1% of hysterectomies, though less common than other complications 3
• Delayed presentation of bowel injury can occur up to 9 days postoperatively 1

Ureteral injury:

• Genitourinary tract injury occurs in 1-2% of major gynecologic surgeries, with 75% occurring during hysterectomy 3
• The transplanted kidney and ureter location in the pelvis creates additional anatomical complexity 5

Vaginal cuff dehiscence:

• Occurs in 0.08% of vaginal hysterectomies, though typically presents with vaginal bleeding rather than upper abdominal pain 3

Immediate Diagnostic Work-Up

First-Line Imaging

CT abdomen and pelvis with IV contrast (no oral contrast):

• This is the definitive imaging study for postoperative complications, with CT being "often the first study and generally considered to be" the most appropriate for evaluating postoperative abdominal pain and fever 1
• CT provides comprehensive evaluation for hemorrhage, abscess, bowel perforation, and biliary pathology simultaneously 1
• IV contrast is essential to detect wall enhancement in cholecystitis, assess vascular injuries, and identify active bleeding 1
• CT has 90% sensitivity for detecting intra-abdominal foreign bodies and can identify retained surgical materials 1
• In postoperative patients, CT allows for abscess drainage should nonoperative management be pursued 1

Laboratory Testing

Immediate labs to obtain:

• Complete blood count to assess for anemia (hemorrhage) or leukocytosis (infection) 1
• Comprehensive metabolic panel including liver function tests and creatinine to assess transplant kidney function and biliary obstruction 4
• Coagulation studies (PT/INR, aPTT) given anticoagulation status
• Lipase if pancreatitis is considered
• Blood cultures if fever is present 1

Alternative Imaging Considerations

Right upper quadrant ultrasound:

• While ultrasonography is the initial imaging test of choice for RUQ pain in general populations, it has limited sensitivity for detecting postoperative abscesses and retroperitoneal hematomas 1
• Ultrasound may be useful as an adjunct if biliary pathology remains the primary concern after CT, but should not delay definitive CT imaging in this acute postoperative setting 1

Plain radiography:

• Conventional radiography has limited diagnostic value in assessment of acute abdominal pain and low sensitivity for sources of fever or abscess 1
• May only be useful if retained surgical sponge is suspected due to classic appearance of sponge markers 1

Critical Clinical Pitfalls

Do not delay imaging based on absence of fever:

• Fever may be absent in approximately 50% of serious intra-abdominal pathology, and immunosuppression in transplant patients can mask typical inflammatory responses 4

Do not rely on clinical examination alone:

• Clinical determination of intra-abdominal pathology is notoriously poor, with misdiagnosis rates of 34-68% without imaging confirmation 1

Do not assume stable vital signs exclude hemorrhage:

• Retroperitoneal hematomas can be hemodynamically stable initially and expand over hours, as demonstrated in case reports of post-hysterectomy bleeding 2

Consider transplant-specific complications:

• The pelvic location of the transplanted kidney and altered anatomy must be considered when interpreting imaging 5
• Immunosuppressive medications increase infection risk and alter typical inflammatory presentations 4

Anticoagulation management:

• Coordinate with transplant nephrology regarding temporary anticoagulation reversal if hemorrhage is confirmed, balancing bleeding risk against thrombotic risk to the transplanted kidney

Management Algorithm Based on CT Findings

If CT shows retroperitoneal hematoma:

• Immediate surgical consultation for potential exploration versus observation 2
• Consider interventional radiology for angiography and possible embolization if active extravasation is identified 2
• Transfusion support as needed with close hemodynamic monitoring 2

If CT shows postoperative abscess:

• CT-guided percutaneous drainage is preferred initial management 1
• Broad-spectrum antibiotics covering gram-negative and anaerobic organisms 3
• Surgical consultation if drainage is inadequate or clinical deterioration occurs 1

If CT shows acute cholecystitis:

• Surgical consultation for cholecystectomy, though timing must be coordinated with recent hysterectomy 1
• Consider percutaneous cholecystostomy if patient is not a surgical candidate 1

If CT is negative or equivocal:

• Admission for serial abdominal examinations every 6-12 hours 1
• Repeat imaging in 12-24 hours if symptoms persist or worsen 1
• Consider MRI with MRCP if biliary pathology remains suspected but CT is inconclusive 1