Patient is a very pleasant 55-year-old female with a past medical history significant for nonoxygen, nonsteroid-dependent COPD on home inhalers, nicotine dependency, alcohol use who presented to the emergency room on 6/28/2021 due to profound fatigue, weakness and skin discoloration.  She also reported feeling off balance increasingly fatigued and short of breath for the past 4 weeks which have been worsening in severity.  She received her Moderna Covid 19 vaccines on May 24th and June 24th. She reported she started noticing that she was having some lower extremity edema around June 5 and talked to a coworker who suggested an over-the-counter diuretic.  She then saw her PCP on June 10 when the edema did not improve and was prescribed Lasix.    She also reported a genital rash a week ago that she thought was a heat rash but has since resolved.  She denied any increase or decrease in her alcohol consumption but admitted she did not drink anything in the last few days prior to arrival due to worsening fatigue and decreased appetite.  She does smoke about a half a pack to a pack daily depending on her stress level.  She arrived to our ER on 6/28/2021 jaundiced and pale and was found to have profound pancytopenia with leukopenia and a fever.  On November 2020 her CBC and differential were normal with a hemoglobin of 13,000 white blood cell count of 7 and platelets of 200,000.  On arrival her white blood cell count was 3.5 with a hemoglobin of 2.9 and platelets of 105,000.  Her absolute reticulocyte count was 0.2 showing a hypoproliferative bone marrow.  Stool OB was negative.  Serum iron was 257 with a TIBC of 287 saturation of 90 and ferritin of 962.  She was transfused 4 units of packed red blood cells and admitted to the intensive care unit.  CT of the abdomen and pelvis was negative for splenomegaly.  Hepatitis panel, B12 level and HIV screening were negative.  Folate level was low at 0.8.  She was started on folic acid.  She was seen in consultation by hematology.  Her peripheral smear appeared to be megaloblastic.  She was also found to have bilateral pneumonia on CT imaging and subsequent chest x-ray imaging.  Due to the fever, leukopenia and pancytopenia she was initially started on vancomycin and Zosyn.  The vancomycin was ultimately discontinued when MRSA nares screen was negative and her clinical condition stabilized.  On arrival she did have an ultrasound of the right upper quadrant and gallbladder which was a normal study as she arrived jaundice with transaminitis.  Interestingly and unexplainably the following day she had repeat CT of the abdomen and pelvis and abdominal ultrasound imaging done which then showed a very abnormal appearing gallbladder with a markedly thickened edematous wall and a small amount of perihepatic fluid, this was confirmed on repeat abdominal ultrasound.  Interestingly this was not seen on ultrasound imaging from just the night before and the case was reviewed with radiology.  CT cystography was also done as there was an unusual fluid collection adjacent to the bladder but this was ultimately a negative study.She also had an echocardiogram done during her hospital stay which revealed a normal left ventricular systolic function the right ventricular was normal in size she had a moderately dilated left atrium and right atrium and trace mitral and tricuspid regurg.  As she did not have any complaints of abdominal pain, nausea or vomiting after discussion with general surgery they did not feel that anything further needed to be done but if patient developed any symptoms of nausea, vomiting or abdominal pain an MRCP would be recommended to further evaluate the gallbladder.  Once her condition stabilized she was transferred out of the ICU to the medical floor.Patient's hemoglobin has remained relatively stable at 8.1 her platelets remain suppressed at 83,000 white blood cell count this morning was 4.2.  Her differential is presently normal with the exception of hypochromic macrocytic and microcytic cells with some polychromasia.   Patient's AST is 87 ALT of 83 and alkaline phos is normal at 111.  Total bilirubin was 2.1 with magnesium of 1.42.  She will be going home on magnesium and potassium supplementation and will need close follow-up with her PCP.  COVID-19 testing x2 was negative.   She will be going home on 3 L of oxygen for now.  Interestingly patient had her COVID-19 vaccines on May 24 and June 24. She has been placed on temporary disability for now from work.  on 7/7/21 she had repeat lab work and her folate level is now normal at 9.43. Her cbc and differential shows wbc 6.7, hgb 9.6 and platelets of 527,000 with lymphopenia 12% and monocytosis of 18%, her cmp is normal except for ast 124, alt 65 and alk phos of 158.