Idiopathic (most common)
Precordial catch syndrome
Sudden, intense pain with deep inspiration, self-resolving
Usually located to one finger point and the intercostal space (often at apex of heart)
Musculoskeletal
Costochondritis, trauma
Pulmonary
Pneumothorax
Pneumonia (peds)
Pulmonary embolism
Aortic dissection
Uncommon but consider with history of connective tissue disease
GI
Esophagitis
Esophageal spasm
Gastritis
Psychosomatic
Panic attack
Anxiety
Cardiac (1%)
Left-sided obstructive lesions
Dysrhythmias
HOCM
Pericarditis
Prinzmetal's angina (vasospasm)
MI
Rare, even post-Kawasaki
Consider coronary artery dissection
Mitral valve prolapse
Anomalous coronary arteries]
Sudden, intense pain with deep inspiration, self-resolving
Usually located to one finger point and the intercostal space (often at apex of heart)
Costochondritis, trauma
Pneumothorax
Pneumonia (peds)
Pulmonary embolism
Aortic dissection
Uncommon but consider with history of connective tissue disease
Uncommon but consider with history of connective tissue disease
Esophagitis
Esophageal spasm
Gastritis
Panic attack
Anxiety
Left-sided obstructive lesions
Dysrhythmias
HOCM
Pericarditis
Prinzmetal's angina (vasospasm)
MI
Rare, even post-Kawasaki
Consider coronary artery dissection
Mitral valve prolapse
Anomalous coronary arteries]
Rare, even post-Kawasaki
Consider coronary artery dissection
Chest pain 
Idiopathic 
Chest wall pain
Precordial catch syndrome
Abdominal pain 
Sudden, intense pain with deep inspiration, self-resolving
Abdominal pain
Usually located to one finger point and the intercostal space 