Brief Answer:
I would like to rule out recurrent parotitis

Detailed Answer:
Hello

Thanks for the query

The site you have mentioned is the anatomical location of parotid gland.The most common cause of parotid swelling in this age group is mumps parotitis.

In the presence of past history of same episode which resolved spontaneously and in the absence of fever the possibility of mumps is unlikely. Parotid gland is one of the salivary gland and helps in saliva production. There may be blockage of the duct (due to the calculi) which causes dryness of mouth on the same side and swelling and pain due to accumulation/non drainage of saliva.
The symptoms may persist for 2-7 days and then suddenly resolve spontaneously with a gush of salivation. The fever is not associated commonly.
The common cause of recurrent parotid swelling is parotid duct calculi. Other uncommon causes are autoimmune disorder (Sjogren syndrome) or juvenile recurrent parotitis (in which the exact cause could not be find out).
I would like to get a routine hemogram and serum amylase done to see any infection or the inflammation(which can cause raised amylase). Second line of investigation should be Ulrasonography and sialography to see the local abnormality and any blockage if it is there. If all these reports are normal autoimmune workup with immune profile should be done to find out the other uncommon causes.

Although the swelling appears to be parotid swelling, it may be a lymph node swelling also, as this is the site of few cervical lymph nodes. The clinical examination and ultrasonography will help in differentiating between these two.
So in the present situation I would get him evaluated by a pediatrician for detailed clinical examination and management accordingly.
I shall be glad to answer if you have any further query.

Regards

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