How to create domain rules from raw unstructured text using NLP and deep learning?
I think your question can be solved using Case Based Reasoning .

Basic principle how it works is, you need to train the model using whole lot of different cases which you have. Based on the symptoms which you give the outcome is predicted(which disease).


Please refer to the links below for deep diving into the topic, appended couple of links with respect to health care industry:


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Do let me know if you need any additional information.