Medical Coding

Answer: C - A04.7, B20 is the correct answer because code A04.7 is the primary code for enterocolitis due to Clostridium difficile, which is the primary reason for admission. The HIV is subsequent in this particular case because it is not the main reason the patient was being admitted. However, it is still necessary to consider for best plan of care and treatment of the patient.
B20 is not the primary code so should not be listed first. R75 is the code for inconclusive serologic evidence of HIV which is incorrect for this patient since this patient has been diagnosed with HIV in the past.