My DD8 has an identical PRI, but slightly higher scores in other areas as compared to your child. I had asked a question about lower comprehension instead of higher PRI, so I will attach the link.
My DD is highly gifted in Math and is about 5 years above her age level, but her reading comprehension is more commensurate with the her age, but on the high side. She is an excellent speller. Her auditory processing and phonemic awareness is amazing. She can nail any word perfectly, although her problem was that she did not know what many words meant. We kept her very sheltered, so a lot of the vocabulary and understanding of real life hinders her ability to fully comprehend things. We use dictionary.com alot to help with those issues.
She has sensorial issues with hearing as well, where she is very sensitive to certain noises.
We used Hooked on Phonics for reading, and DD flew through that at ages 3 and 4. Spellingcity.com is a great site for spelling.
http://giftedissues.davidsongifted....IV_low_comprehension_scor.html#Post79674Good luck!