Strange lump on 15 year olds back

[Letsnotupsettheapplcart]

We have just noticed this lump on my son’s back. Image attached hopefully. Any ideas? I’ve reverse google searched and not had much luck. We’re on holiday at the moment but have booked him a GP appt for Tuesday. It’s not sore

Don’t know, but what are those purple marks nearby, are they usually there? Wondering whether they’re infection tracking marks.

They look like stretch marks to me... I hope he's ok OP, in all honesty I haven't seen anything like that lump before.

The purple marks have been there a few weeks I think. We’ve been on holiday and just thought they were bumps from the pool

What do infection tracking marks mean? Excuse my ignorance

Hard to get a sense of scale but could be a lipoma? V common benign fatty lump. (And yes those are definitely stretch marks! My teen has them!)

The purple marks look like
new stretch marks. I have had something fairly similar with quite open/stretched pores that turned into a cystic spot, so it could be that. Could you try holding a very hot cloth/flannel over and see if that helps, assuming it’s not painful or sensitive. I can’t see that would do much harm if it’s not but I’m not medically trained.

It’s a little bigger than a 50 pence piece. He is growing a great speed so stretch marks would make sense

Is it itchy or tender? Bites can come up like that sometimes, especially on holiday.

No neither. We have been back from holiday about 2 weeks now. We’re currently away at Center Parcs and wouldn’t have known about it had we not seen it in the pool

My son is covered in these lines, same age, and they're just stretch marks as grew really fast.

The lines are definitely stretch marks, v common for growing teenage boys to get them there. They will fade to white .
The lump- hard to tell, could be a fatty lump (lipoma, benign) but the pitting is unusual, so it needs to be checked over in case there is an infection there.

I’m wondering if the enlarged pores are because the skin is stretched? GP appt booked so hopefully can sort quickly.

Thanks everyone for taking the time to reply

https://en.m.wikipedia.org/wiki/Lymphangitis

They’re lines of infection spreading from an infection site and need medical attention.

Sounds like the purple marks are not new though, so not that!

Is it at the base of the spine/top of the bum crack? Quite common to get cysts there.

Yes it is. Base of back. Not as low as bum crack but not far above waist line

The lump looks like a sebaceous cyst.

I think I’ve attached the uncropped image

Not a medic but my guess would be pilonidal cyst.

And this is it now. We had just got out of the pool earlier

I think those are stretch marks by it, but above the lump it looks like there might be a smaller similar one? I can see faint pitting there too. Anyway, it definitely needs checking.

What’s the red area above it?

I realise I sound like the alarmist on this thread - apologies - but spreading infections are something to be alert to.

I'd go into a local pharmacy and get them to look they may br able to give something if not they will definitely advise you what to do and in what time frame.

I’ve managed to move his GP apt to tomorrow afternoon. It’s a video appt but hopefully that’ll be sufficient for them to see what’s what

Cellulitis. Trademark orange peel skin. Needs antibiotics