CD4 and chronic kidney disease: A 74-year-old man with known HIV (CD4 234 cells/mm3, VL undetectable, on Bictegravir/Emtricitabine/Tenofovir alafenamide), dementia, hypertension (HTN), stage 3 chronic kidney disease (CKD), and presumed gastric carcinoma treated with one dose of pembrolizumab, presented to the ED with abdominal pain, fatigue, and altered mental status.