Unintentional weightloss and low immunity in 6 year old girl

[VM78]

I'm worried abot my 6 1/2 year old niece. She has dropped from an lean, tall and rather muscular 97th percentile to just over 20th percentile in the last 6 months. She is pale, quieter than usual, catching every infection she comes in contact with, her lymph nodes aren't huge but weirdly hard (imagine frozen peas or dried beans under skin). She has been a picky eater in the past but this seems to be more than just a result of that behaviour re-occuring.
Do I have reason to be concerned?

[VM78]

I've asked our mum (an RN with thirty years experience) to try talk with my sister about it. I can't repeat in polite company my mothers reaction to the last photo of neice sent to her (shes overseas at present). Family wise its just me, my sister and her partner living close enough for regular contact.  

[margypops]

as I said on the other post I think a serious chat with parents is in order about your concerns ., what other family has she in her life ?

[VM78]

why did that double post grrrrr

[VM78]

Thanks for your comment. Your answer is about what  what I expected given her symptoms. Now I just have to convince her mum I'm not being reactionary or overbearing. Oh the perils of dealing with family..........without employing a taser gun or the judicious use of a moderate dose of Haldol.      

[VM78]

Thanks for your comment. Your answer is about what  what I expected given her symptoms. Now I just have to convince her mum I'm not being reactionary or overbearing. Oh the perils of dealing with family..........without employing a taser gun or the judicious use of a moderate dose of Haldol.      

[caregiver222]

Yes. I recommend she be evaluated as soon as possible at a teaching hospital in the pediatrics department. Not by her stand-alone pediatrician, no matter how competent or nice he/she may be.  In addition I would insist upon a tuberculosis test.