What are the causes of costochondritis in a patient with sharp pleuritic pain below the left nipple, normal electrocardiogram, and unchanged calcified infrahilar lymph nodes?

What Causes Costochondritis

Costochondritis is primarily caused by trauma to the chest wall, post-surgical complications (especially with infection or hematoma), repetitive physical strain, and severe coughing, though in many cases no specific trigger is identified. 1

Primary Etiologic Categories

Traumatic and Mechanical Causes

• Direct chest wall trauma initiates the inflammatory process at the costochondral or chondrosternal joints 1
• Repetitive movements such as heavy lifting or overuse of chest muscles can trigger inflammation 2, 3
• Severe or persistent coughing places mechanical stress on the costochondral junctions 2
• Rib fractures and other chest wall injuries can lead to secondary costochondritis 1
• Pectoral muscle strains or spasms may contribute to or mimic costochondritis symptoms 1

Post-Surgical Complications

• Infection or hematoma formation following chest surgery are significant risk factors 1
• Pain is more common when surgical incisions cut across Langer lines of tension 1
• Breast implants, particularly subpectoral placement, can be associated with costochondral pain 1
• Postsurgical scarring, nerve regeneration, or focal nerve injury due to ischemia, radiation, or lymphedema may cause persistent symptoms 1

Infectious Causes (Rare)

• Infectious costochondritis typically develops when infection spreads directly from a postoperative wound or adjacent foci 2
• Pseudomonas aeruginosa and other bacterial pathogens can cause infectious costochondritis with or without sternal osteomyelitis 2
• Tubercular costochondritis is an extremely rare form of extrapulmonary tuberculosis affecting the ribs, often misdiagnosed for years 4

Associated Systemic Conditions

Inflammatory and Rheumatologic Disorders

• Axial spondyloarthritis: Anterior chest wall pain affects 30-60% of these patients and may be the first disease manifestation 5
• SAPHO syndrome (synovitis, acne, pustulosis, hyperostosis, and osteitis) is a chronic relapsing condition that often involves the sternoclavicular joints 5
• Fibromyalgia and fibromyositis are associated with musculoskeletal chest wall pain that may mimic or coexist with costochondritis 1

Other Contributing Factors

• Nerve entrapment, particularly of the lateral cutaneous branch of the third intercostal nerve, can cause or contribute to symptoms 1
• Diabetes mellitus may be a risk factor, particularly for infectious costochondritis 2, 4

Important Clinical Context

Costochondritis accounts for approximately 42% of all nontraumatic musculoskeletal chest wall pain, making it the most common cause in this category 1, 5. The condition represents inflammation of the costochondral or chondrosternal joints, with the hallmark finding being reproducible tenderness to palpation of the affected joints 1, 6.

Key Distinguishing Features

• Unlike cardiac ischemia, costochondritis presents with sharp, pleuritic pain that worsens with respiration or palpation 7, 6
• Pain that is localized at the tip of one finger over a costochondral junction is not characteristic of myocardial ischemia 7
• Pain reproduced with movement or palpation of the chest wall argues against cardiac causes 7

Common Pitfall

While 7% of patients whose pain was fully reproduced with palpation were ultimately found to have acute coronary syndrome in one study 7, the presence of reproducible chest wall tenderness in patients over 35 years or with cardiac risk factors still requires ECG evaluation to exclude life-threatening cardiac causes 6, 3.