Diagnosis: Costochondritis (Costosternal Syndrome)
The most likely diagnosis is costochondritis (costosternal syndrome), characterized by bilateral tenderness over multiple costochondral junctions (ribs 3-6) following a recent upper respiratory infection with coughing. 1
Key Diagnostic Features Supporting Costochondritis
The clinical presentation demonstrates the hallmark findings of costochondritis:
Bilateral involvement of ribs 3-6 at costochondral junctions – This anatomic distribution is classic for costochondritis, which affects the costochondral junctions of ribs 3-7, most often presenting bilaterally or on the left side. 2
Reproducible tenderness on palpation – The defining physical finding is tenderness to palpation of the affected costochondral joints, which confirms a musculoskeletal origin. 2, 3, 4
Recent upper respiratory infection with coughing – Trauma to the chest wall from repetitive coughing can initiate the inflammatory process that leads to costochondritis. 3 This represents approximately 42% of all nontraumatic musculoskeletal chest wall pain. 3
Normal vital signs and well-appearing patient – These findings support a benign musculoskeletal etiology rather than a life-threatening cardiac or pulmonary condition. 1
Why Not the Other Diagnoses?
Tietze Syndrome is excluded because it presents with localized inflammation of typically one or two costochondral joints (usually ribs 2-3) with visible or palpable swelling, not the bilateral, multi-level tenderness described here. 1, 5
Precordial Catch Syndrome is excluded because it presents with sudden, brief (seconds to minutes), sharp periapical pain that is intensified by inspiration and typically occurs at rest without preceding illness. 1, 6, 7, 8 The pain is described as sudden, easily localized to one point, nonradiating, and nonexertional. 8 This patient's presentation of persistent tenderness over multiple bilateral sites does not fit this pattern.
Slipping Rib Syndrome is excluded because it involves ribs 8-10 (the false ribs), not ribs 3-6, and presents with actual rib subluxation, clicking or popping sensations, and often chest wall asymmetry. 2, 9 Physical examination reveals a mobile or popping rib with palpation in most cases. 9
Clinical Approach
The diagnosis is primarily clinical based on physical examination findings. 4
ECG should be obtained within 10 minutes in patients >35 years or those with cardiac risk factors to exclude acute coronary syndrome, though this 16-year-old with normal vitals and reproducible chest wall tenderness has low cardiac risk. 2, 4
Imaging is reserved for atypical presentations and is not indicated in this straightforward case. 2, 4
Laboratory studies are not useful for establishing the diagnosis, though inflammatory markers may be modestly elevated. 2, 4
Critical Pitfall
Do not assume reproducible chest wall tenderness completely excludes cardiac disease – In one study, 7% of patients whose chest wall pain was fully reproduced by palpation were ultimately diagnosed with acute coronary syndrome. 3 However, in this well-appearing 16-year-old with normal vital signs and a clear precipitating cause (coughing), the pretest probability of cardiac disease is extremely low.
Management
First-line therapy: NSAIDs for 1-2 weeks as the standard anti-inflammatory approach. 2, 3
Second-line: Add low-dose colchicine if symptoms persist despite NSAIDs. 2, 3
Adjunctive measures: Ice or heat application, acetaminophen when NSAIDs are contraindicated, and topical lidocaine patches for localized relief. 2, 3
Reassessment is required if pain persists beyond the expected treatment course to exclude other etiologies. 2