Brief Answer:
She may be suffering from serum sickness like syndrome

Detailed Answer:
Hello

Thanks for the query. I have gone through the uploaded images.

Low platelet count with rashes and pain in joints can be there in a number of conditions. The common causes are viral infections, some inflammatory disorders like juvenile idiopathic arthritis,systemic lupus erythematosus, hypersensitivity vasculitis or serum sickness like syndrome. Your doctors may have diagnosed her as a case of serum sickness like syndrome.
Serum sickness like syndrome is an immunological disorder and can again be due to various causes like infection or medications.
But thrombocytopenia is unlikely in this condition and it is more common in inflammatory disorders.The rash can be due to low platelet or disease itself. I have seen the image and the type of rash is seem to be due to vascular or immunological in origin and not due to low platelet
A battery of investigation is needed due to quite a large numbers of etiology to make a diagnosis like hemogram,CRP,ANA,ESR,complement studies and rheumatoid factor.
The management is mainly NSAIDS and steroid.
It is confusing to me that why your doctors have stopped the steroid as it is a mode of treatment in serum sickness like syndrome.
I request you to upload the investigations so that it would be better for me to help you out.
Regards

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Brief Answer:
Thanks for giving value to my opinion

Detailed Answer:
Thank you very much for giving value to my opinion and also for giving the feedback. I would like to know whether she has been diagnosed as a case of serum sickness or something else.It will be my pleasure to answer if you have any more queries.
Regards

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