Diagnostic Approach for Right Lower Quadrant Pain

Initial Evaluation and Imaging

The American College of Radiology recommends obtaining a contrast-enhanced CT scan of the abdomen and pelvis immediately, as this is the primary diagnostic imaging modality for evaluating RLQ pain with fever, achieving sensitivities of 85.7-100% and specificities of 94.8-100% for identifying appendicitis and alternative pathologies 1, 2
A focused evaluation should look for migratory pain pattern, as this increases the likelihood of appendicitis, with a reported sensitivity and specificity in the context of appendicitis diagnosis 3, 2
The presence of a psoas sign, which is tested for by pain with hip extension or flexion, suggests appendicitis or retroperitoneal pathology, as indicated by the World Journal of Emergency Surgery 4
The timing of symptom onset relative to heavy lifting or meat consumption is crucial for differential diagnosis, as documented by the World Journal of Emergency Surgery 4

The World Journal of Emergency Surgery suggests that C-reactive protein levels are significantly higher in appendicitis versus other etiologies, and normal inflammatory markers have 100% negative predictive value for excluding appendicitis 5
A basic metabolic panel should be ordered to assess for dehydration and electrolyte abnormalities if infection is present, as recommended by the World Journal of Emergency Surgery 4
CT with IV contrast is the definitive test, reducing negative appendectomy rates and identifying alternative diagnoses including psoas abscess, mesenteric adenitis, diverticulitis, and infectious colitis 1, 2, 4

The American College of Radiology indicates that appendicitis is the most likely diagnosis given the classic presentation with RLQ pain and fever, with a sensitivity of 90-100% and specificity of 94.8-100% for contrast-enhanced CT without enteral contrast 3, 1, 2
Heavy lifting can cause psoas injury, and CT should evaluate for psoas enlargement or fluid collection, as suggested by Praxis Medical Insights 6
If appendicitis is confirmed, the standard treatment is appendectomy, and for perforated appendicitis with abscess, percutaneous drainage followed by delayed surgery should be considered, as recommended by Praxis Medical Insights 6

The World Journal of Emergency Surgery advises against relying on clinical scoring systems alone for diagnosis, as they may not accurately exclude appendicitis, particularly with atypical histories 5
The American College of Radiology recommends against delaying imaging for oral contrast, as this increases time to diagnosis and potentially increases perforation risk without improving diagnostic accuracy 3, 1
A broad differential diagnosis should be considered, including psoas muscle strain, infectious enterocolitis, and typhlitis, especially given the history of heavy lifting and meat consumption, as indicated by Praxis Medical Insights and the World Journal of Emergency Surgery 6, 4