Hi and thank you so much for this query. I am so sorry to hear about what your son experienced and this surgery. I am however happy the surgery went on smoothly and the recovery so far has been great. Appendicitis has no clear cause. From the definition, it simply means an inflamed appendix and the cause is not know nor the exact mechanism that leads to this. Though there are many hypotheses that seek to suggest what the possible mechanism is, there is just not single cause that stands very straight forward. This diagnosis is often clinical and you need no second opinion. Also, your symptoms, findings and timeline are very suggestive of acute appendicitis. I am pretty sure you took the right decision and sure that is why your son if feeling a lot better after the surgery. I hope this helps. I wish you well. Thank you so much for this opportunity to address your health query. Thanks. Dr. Ivo, MD.