Brief Answer:
There can be many possible cause , most common being infection .

Detailed Answer:
Hello XXXX,
How are you ? I am Dr Rahul Rathee and i would be honoured to answer your query and rectify your doubts and concerns .
Well there can be many possible cause for wound and discharge from navel . I would like to innemurate the possible causes in order of frequency from most common to least common -
(1) Infections - Infections are the most cause and various possible infections includes -
(a) Fungal infections
(b) Bacterial infections

(2) Sebaceous cyst - These are the small bumps underneth the skin around roots of hair follicles or in deep layers of skin . Any infection by bacteria or fungus in these cysts can lead to formation of wound and discharge from navel

(3) Pregnancy - Streching of the skin and underlying tissues by the growing fetus inside womb makes the tissues around navel weak and prone to various infections

(4) Diabetes - Uncontrolled Diabetes makes the body prone to developing various infections including navel or for that matter any part of the body

(5) Umblical Hernia

(6) Psoriasis - It is a disease of the skin and can involve any part of the skin including navel

Now coming to your second question as to what to do ? You need to visit your surgeon or physician ( who so ever is available near by you ) . He would perform a clinical examination of your wound and would prescribe you some laboratory tests including some blood tests and tests of the discharge coming out from your wound , so as the make a precise diagnosis of the underlying cause of the wound and discharge . Once a precise diagnosis is made he will prescribe you the appropriate treatment .
I hope i have answered your doubts to your satisfaction but if you still have any further doubts , please feel free to ask me . If you are satisfied , kindly close the discussion .
Take Care Pauline
Dr Rahul Rathee .

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