Brief Answer:
Hidradenitis suppurativa & recurrent furunculosis are likely possibilities

Detailed Answer:
Hello. Thank you for writing to us at healthcaremagic

I have taken note of your query and I have understood your concern.

Persistent and recurrent painful boils and abscesses leading on to scaring at inner thigh area suggests a possibility of Hidradenitis suppurativa.
Another possibility is of recurrent bacterial skin infections i.e furunculosis.

There is no reason as to why only stretch marks would be predisposed to develop these skin lesions.

Hidradenitis Suppurativa is a disease of apocrine sweat glands bearing area characterized by recurrent painful deep bumps and abscesses that rupture, scar and may form sinus tracts.
Sites like perineaum, axilla, areola etc are rich in apocrine sweat glands are one or more of these may be affected.
The inciting factor in hidradenitis suppurativa is follicular occlusion with secondary bacterial colonization.
In later stages, hidradenitis is associated with fibrosis/ scaring from previously healed lesions and sinus tracts. This is quite distinctive of HS.
Hidradenitis suppurativa affects women more commonly than men.

The best way to approach Hidradenitis is to start an oral antibiotic.

Oral antibiotics are often part of the treatment plan in hidradenitis suppurativa patients. Antibiotics can fight infection, prevent it from worsening, and stop new breakouts.

My choice of oral antibiotic would be Amoxycillin 500 mg in combination with clavulanic acid 125 mg, thrice daily

Or

Cephalexin 500 mg, thrice daily

Or

Cefadroxil 500 mg, twice daily.

Oral antibiotics would take care of the secondary bacterial infection and inflammation that accompanies.
Sometimes antibiotics may need to be continued for a longer duration.

An OTC antibacterial cream/ointment e.g 2% Mupirocin can be applied twice daily.

I suggest that you visit a dermatologist for a confirmatory diagnosis and for the needful.

Regards

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