Linear scleroderma and chronic cough

hi everyone…
i havent wrote here before…my son ben has linear scleroderma.he is 16yrs old and had alot of different medical problems,which i wont go into at the mo…he was diagnosed with .morphea at first,then it went all the way dwn his left leg in no time at all…so they said it was linear…he has been having methotrexate injections for about a yr now and has slowed it right dwn…he does however have abit on his chest…but it is not getting any worse,thank god…
i am really worried that something else is goin on tho…he has lost alot of weight and is very pale…they are keeping an eye on him with regular bloods,but he has also had a chronic cough for 3weeks…i know this doesnt sound along time ,but this same thing happened back in october…it went on for 13weeks and he went very ill…all that im reading and what docs are saying is that linear doesnt involve the internal organs…great…but why is my son getting soo ill???
could he possibly have another part of the sclroderma??what i mean to say is,does anyone know if u can have linear and scleroderma which affects the internal organs??
sorry this is abit long,but i am at my wits end here…wood be really great to hear from u guys and to have ur views.

samantha xx