ADMITTED ON 10/4/2021: 74 y/o M with PMHx including CKD4, HFrEF / cardiomyopathy (EF 35-40% on last echo), CAD, AFib, pulmonary sarcoidosis, chronic immunosuppression and anticoagulation, etc., presented to the ER complaining of progressive shortness of breath, cough and fevers at home.  He had received his Pfizer COVID-19 booster injection on last Tuesday.  On the following day, he began to notice shortness of breath and cough.  He subsequently developed fevers, generalized weakness with myalgias, etc.  He became more short of breath today and presented to the ER for evaluation.  Upon arrival, his oxygen saturation was 90% on room air.  ABG revealed hypoxemia with PO2 of 53.  His SpO2 improved with 2 L supplemental oxygen.  Imaging was consistent with viral pneumonia.  With concern for COVID-19 and hypoxemia with multiple comorbid conditions, he was admitted to the COVID step-down unit for further workup and management.   As mentioned, the patient is fully vaccinated COVID and has received his booster.  However, he is immunosuppressed with azathioprine and chronic prednisone.   He is followed by Pulmonary  DISCHARGED 11/2/2021: Discharge Summary Information Attending Physician, Consulting Physician, Primary Care Physician   Discharge Diagnoses:  1. COVID-19 virus infection, Discharge, 10/04/2021 2. Hypoxemia, Discharge, 10/04/2021 acute hypoxic resp failure 3. CKD (chronic kidney disease), stage IV, Discharge, 10/04/2021 4. CAD (coronary artery disease), s/p multiple PCI/stents, Discharge, 10/04/2021 5. Atrial fibrillation, s/p PVI, Discharge, 10/04/2021 6. HFrEF (heart failure with reduced ejection fraction), Discharge, 10/04/2021 acute on chronic 7. Cardiomyopathy, Discharge, 10/04/2021 8. Chronic anticoagulation, Discharge, 10/04/2021 9. Pulmonary sarcoidosis, Discharge, 10/04/2021 10. Immunosuppression, Discharge, 10/04/2021 11. OSA on CPAP, Discharge, 10/04/2021 12. Class 1 obesity with body mass index (BMI) of 31.0 to 31.9 in adult, Discharge, 10/04/2021 13. Arthritis, Discharge, 10/04/2021  Secondary Diagnosis and Comorbidities: Hospital Course    SARS-CoV-2, viral pneumonia due to COVID-19. Acute respiratory failure with hypoxemia.  - Fully vaccinated and rec?d booster 9/28  - Symptoms began 9/29  - Completed course dexamethasone, 10/14  - Rec?d tocilizumab 10/9  - Completed course remdesivir, 10/9   -CTA chest w/o PE -Back on Imuran for Sarcoid -His oxygenation has ben slow to improve but is now at a manageable level at 6 to 7L -Medical facility states they will take him on current O2 needs   AKI on CKD stage IV/Hyperkalemia.  - Nephrology consulted, following  - SCr  in general has been stable  - Potassium up slightly again on 10/19 - but improved w/ restarting lasix  - Renal diet  - Has some volume overload on exam now on po lasix per Nephrology -Creatinine is stable  Extensive cardiac history, including CAD s/p multiple PCI/stents, atrial fibrillation s/p PVI, Acute on chronic HFrEF, cardiomyopathy. On chronic anticoagulation.  - Appeared volume overloaded w/acute CHF  - Now on lasix  - Rate controlled; monitoring on telemetry  - Initially on therapeutic Lovenox due to DOAC/dexamethasone interaction, now no interaction concerns   Pulmonary sarcoidosis on immunosuppression.  - Complicates #1  - Azathioprine to be possibly resumed  in AM pending labs  - Initially held his home prednisone while on dexamethasone  - Restarted prednisone as he has completed Decadron  - Will eventually need to f/u with his pulmonologist -Resumed imuran, follow LFT in one week  Class 1 obesity. OSA on CPAP.  - BMI > 31  - Complicates overall care & prognosis  - CPAP qHS  -he says will bring his home machine when goes   HTN.  - normotensive  - Restarted home losartan and metoprolol  Depression.  -improved, especially now with some light at the end of the tunnel, moving to rehab