What is the appropriate evaluation and management of left upper quadrant (LUQ) pain in a male patient on testosterone (hormone replacement) therapy?

Left Upper Quadrant Pain in a Male on Testosterone Therapy

CT abdomen and pelvis with contrast is the most appropriate initial imaging study for evaluating left upper quadrant (LUQ) pain in this patient, as it provides excellent diagnostic yield for both acute abdominal pathology and testosterone-related complications. 1

Initial Clinical Assessment

Key History Elements to Obtain

• Duration and character of pain: Determine if pain is acute (days) versus chronic, cramping versus sharp, and whether it radiates 2
• Testosterone administration details: Route (intramuscular vs. transdermal), injection site if applicable, duration of therapy, and timing of pain onset relative to testosterone initiation 3, 4
• Associated symptoms: Fever, leukocytosis, changes in bowel habits, urinary symptoms, or constitutional symptoms 1
• Reproductive organ status: In transgender males, presence or absence of uterus/ovaries is critical, as 69.4% of trans-masculine persons on testosterone report new-onset abdominopelvic pain 3

Physical Examination Priorities

• Localization: True LUQ pain versus suprapubic or lower quadrant pain mischaracterized by the patient 3
• Injection site examination: If using intramuscular testosterone, examine for localized muscle tenderness, swelling, or dark urine suggesting rhabdomyolysis 4
• Abdominal examination: Assess for peritoneal signs, masses, organomegaly, or focal tenderness 1, 2

Diagnostic Imaging Approach

First-Line Imaging

CT abdomen and pelvis with IV contrast is rated 8/9 (usually appropriate) by the American College of Radiology for evaluating left-sided abdominal pain. 1 This modality offers:

• 69% sensitivity and 100% specificity for acute abdominal pathology in the LUQ 2
• Ability to identify splenic pathology, renal issues, colonic disease, pancreatic tail abnormalities, and reproductive organ complications 1, 2

Alternative Imaging Considerations

• Ultrasonography may be considered initially if splenic or renal pathology is strongly suspected, though it has lower diagnostic yield than CT 1
• MRI is rated 4/9 (may be appropriate) and should be reserved for patients requiring radiation avoidance 1
• Plain radiography has limited diagnostic value (rated 4/9) and should generally be avoided 1

Testosterone-Specific Complications to Consider

Reproductive Organ Pathology (if applicable)

In transgender males with retained reproductive organs, new-onset abdominopelvic pain occurs in 69.4% after testosterone initiation, with median onset at 1 year (range: 1 month to 20 years). 3 Key features include:

• Suprapubic localization in 78.7% of cases 3
• Cramping, intermittent pain in 75-80% 3
• Patients with uterus/ovaries are 9.5 times more likely to have suprapubic pain 3
• All 28 patients reporting pain resolution achieved this through hysterectomy 3

Injection-Related Complications

Localized rhabdomyolysis can occur with intramuscular testosterone, particularly in smaller muscle groups like the deltoid. 4 Warning signs include:

• Dark-colored urine 4
• Focal muscle pain at injection site 4
• Elevated creatinine kinase levels 4
• Management: Switch to subcutaneous testosterone or use larger muscle groups (thigh/gluteus) 4

Hematologic Complications

Monitor for polycythemia-related complications, as hematocrit >54% occurs in up to 43.8% of patients on injectable testosterone. 5, 6 Elevated hematocrit increases blood viscosity and can cause:

• Abdominal vascular thrombosis 6
• Splenic infarction (though rare)
• Action required: Dose reduction or temporary discontinuation if hematocrit >54% 1, 5

Laboratory Evaluation

Essential Initial Labs

• Complete blood count: Check for leukocytosis (infection/inflammation) and hematocrit elevation 1, 5
• Comprehensive metabolic panel: Assess renal function and electrolytes 6
• Creatinine kinase: If injection-site pain or dark urine present 4
• Lipase/amylase: If pancreatic pathology suspected 1

Testosterone-Specific Monitoring

• Hematocrit should be checked every 3-6 months during the first year of testosterone therapy, as most changes occur within the first 3 months 5
• If hematocrit is elevated, consider therapeutic phlebotomy or blood donation in addition to dose adjustment 5

Common Diagnostic Pitfalls

Critical Errors to Avoid

1. Assuming musculoskeletal pain without imaging: While upper quadrant musculoskeletal pain exists 7, visceral pathology must be excluded first in acute presentations 1, 2
2. Overlooking reproductive organ complications: In transgender males, failure to consider retained reproductive organs as pain source delays appropriate management 3
3. Missing injection-related rhabdomyolysis: Dark urine with injection-site pain requires immediate CK measurement and hydration 4
4. Ignoring polycythemia: Testosterone-induced erythrocytosis can cause thromboembolic complications requiring urgent intervention 5, 6

When Imaging May Be Deferred

Imaging may not be necessary if:

• Patient has mild, clearly musculoskeletal pain with normal vital signs and no red flags 7
• History of recurrent, benign condition (e.g., costochondritis) with identical presentation 1

However, given the moderate sensitivity (69%) of clinical assessment alone, a low threshold for CT imaging is appropriate in the acute setting. 2

Management Based on Findings

If CT Identifies Acute Pathology

• Diverticulitis: Medical management for mild cases; surgical consultation for complicated disease 1
• Splenic pathology: Hematology consultation if splenic infarction or hematologic disorder identified 2
• Reproductive organ pathology: Gynecology consultation; definitive treatment may require hysterectomy 3

If CT is Negative

• Negative predictive value is 83% 2
• Consider non-imaging diagnoses: functional pain, early inflammatory process, or musculoskeletal causes 2, 7
• 12% of patients with negative CT ultimately receive clinical diagnosis of pathology undetectable on imaging 2
• Close follow-up is essential; repeat imaging if symptoms worsen or persist 1, 2

Testosterone Therapy Modifications

• Continue monitoring hematocrit regardless of imaging findings 5, 6
• If injection-related complications identified, switch to transdermal or subcutaneous formulations 5, 4
• Injectable testosterone carries highest risk of complications (43.8% erythrocytosis rate) compared to transdermal (2.8-17.9%) 5