YEL-AVD (Yellow Fever associated viscerotropic disease) Patient states he was in his normal state of health of 23 Aug 2019 when he received 3 vaccines as part of his immunization requirements to include AVA #1, Typhoid and YF-Vax. He tolerated the vaccines well without any immediate adverse reactions. Within a few hours, he developed bilateral shoulder soreness that lasted about 3 days before resolving. He then did fine until Monday, 2 Sep when he awoke with some subtle left sided chest discomfort. Patient describes the chest discomfort began as a tugging/pulling sensation in his left chest. The pain progressed the following day and began to have associated dyspnea which was worse when lying down or when taking a deep breath. His symptoms continued to worsen and he sought care in the ED on 6 Sep 19. There he was noted to have a (+) D-dimer and CTPA done which did not reveal a PE but did show a small -moderate sized left-sided pleural effusion. In addition, he was noted to have an elevated creatinine and liver associated enzymes. He was hemodynamically stable, oxygenationg at 98% on RA and afebrile in the ED. He also endorses some chills and night sweats that developed during this time. He notes having daily headaches, as well. He further describes his chest pain as a constant dull pain 4 out of 10 in intensity but with acute excaerbations of a sharp pain (9 out of 10) with deep inspiration or lying down. Upon presentation today, he states his symptoms are all resolved other than rare episodes of substernal chest discomfort that occur at rest and resolve within a couple minutes, which he notes as distinctly different than his original pain and dyspnea.He denies any associated nausea, vomiting or diarrhea associated with his symptoms, but did endorse some LH associated with his dyspnea. He denies any recent travel and has never been outside the country. No high risk sexual encounters, etc. He denies a history of atopy/allergies. He received all routine childhood vaccines without any adverse reactions. Patient denies any other known adverse events following immunizations. Patient states he tolerates ingestion of eggs and gelatin and denies any known adverse reactions to latex, neomycin, polymixin, streptomycin, thimerosal, yeast, or formaldehyde.  Patient with clinical history and laboratory findings most consistent with Yellow fever vaccine associated viscerotropic disease (YEL-AVD). This is a rare Adverse Event Following Immunizations (AEFI) that was first described in 2001. It is reported to occur in 0.3 per 100,000 vaccines and is exclusively seen in patients receiving the YF-Vax for the first time, typically occurring within 1-8 days following vaccination but has been reported as far out as 18 days (patient's symptoms began at 10 days out from vaccination). YEL-AVD mimics naturally acquired yellow fever disease with the vaccine virus proliferating and disseminating throughout the patient's tissues. YEL-AVD is defined as acute multiple organ system dysfunction that occurs following vaccinization; it can range from relatively mild multi-system disease to severe multiple organ system failure and death. Initial symptoms of YEL-AVD are nonspecific including fever, headache, malaise, arthralgias, myalgias, nausea, vomiting and diarrhea; as it progresses it can include thrombocytopenia, elevation of transaminases, bilirubin and creatinine; less frequent manifestations include rhabdomyolysis and DIC. YEL-AVD is fatal in more than 60% of reported cases. Unfortunately, patient has no baseline CMPs/BMPs to compare his elevated LAEs and creatinine to. However, his LAEs are already trending down. The patient had multi-system organ involvement to include pleural effusion with dyspnea, elevated liver associated enzymes and acute kidney injury, elevated fibrin degradation products, as well as headaches. I suspect that patient will meet Brighton Collaboration case definition for viscerotrophic disease (level 2 of diagnostic certainty) with elevated Fibrin Degradation Products (elevated D-dimer) as well as a creatinine >/= 1.5 times his baseline value. (baseline value pending but suspect as patient convalesces his creatinine will decrease to less than 1 which will then meet this criteria). Interestingly, several cases of YEL-AVD have involved a history of autoimmune disease or diseases with potential autoimmune etiology. The literature includes 3 patients with SLE, 2 with Addison's disease, 1 with Crohn's disease, 1 with PMR and hypothyroidism, 1 with UC and 1 with myasthenia gravis. This patient has known mild eosinophilia with recent striae and weight gain, as well as some white and blue color changes to his digits. As suggested by his pulmonologist it is prudent to rule out Addison's disease as well as CVD given the literature and patient's history. No history of immunodeficiency, but given YEL-AVD can be associated with immunodeficiency will rule out common immunodeficiency with screening flow cytometry and quantitative Immunoglobulin levels; of note, patient denies a history of thymectomy or myasthenia gravis. Patient should not receive YF-Vax in the future but would not have an indication for such anyways. Patient may receive AVA and Typhoid as needed in the future but would consider dosing them in isolation from other vaccines. Serum sent to CDC for PRNT testing which may also provide some additional diagnostic certainty (already in discussions with Dr.).Patient currently feels his is back to his pre-immunization baseline.