Vaccination failure; Hepatitis A virus infection; Generalized weakness; Jaundice; Death NOS; This case was reported in a literature article and described the occurrence of unknown cause of death in a 58-year-old male patient who received Hepatitis A vaccine for prophylaxis.   The patient's past medical history included hepatitis a. Concurrent medical conditions included hepatic cirrhosis and alcoholic.   On an unknown date, the patient received Hepatitis A vaccine at an unknown dose. In April 2019, unknown after receiving Hepatitis A vaccine, the patient experienced vaccination failure (serious criteria hospitalization and GSK medically significant), hepatitis a (serious criteria hospitalization), weakness generalized (serious criteria hospitalization) and jaundice (serious criteria hospitalization). On an unknown date, the patient experienced unknown cause of death (serious criteria death and GSK medically significant). On an unknown date, the outcome of the unknown cause of death was fatal and the outcome of the vaccination failure, hepatitis a, weakness generalized and jaundice were unknown. The reported cause of death was unknown cause of death.   It was unknown if the reporter considered the unknown cause of death, vaccination failure, hepatitis a, weakness generalized and jaundice to be related to Hepatitis A vaccine.  Additional details were provided as follows: This case was reported in a literature article and described the suspected vaccination failure in a male patient aged 58-year-old who was vaccinated with unspecified hepatitis A vaccine (manufacturer unknown) for prophylaxis.  The patient had a history of liver cirrhosis and Hepatitis A virus (HAV) infection. The patient had daily alcohol use. The patient was negative for human immunodeficiency virus (HIV). No information on patient's family history or concomitant medication was provided. On an unspecified date, the patient received unspecified hepatitis A vaccine one time (administration route and site unspecified; batch number not provided). The age at vaccination was not provided.  On an unspecified date in April 2019, unknown period after vaccination, the patient presented to the emergency department (ED) with generalized weakness and jaundice for one week. The patient denied recent travel or drug use, however, admitted to daily alcohol use. The patient's vital signs were normal. Physical exam was unremarkable aside from generalized jaundice. Laboratory results were relevant for markedly elevated transaminases, international normalized ratio (INR) and total bilirubin. On day of admission, the patient's lab test showed alanine aminotransferase (ALT) at 1813, aspartate aminotransferase (AST) at 933, total bilirubin at 19.97. direct bilirubin at 11.94, INR at 2.18 and alkaline phosphatase at 225 (normal range and units not reported for all).  In April 2019, from admission, Ethanol and acetaminophen levels were negative, polymerase chain reaction (PCR) did not detect hepatitis B virus deoxyribonucleic acid (HBV DNA) and hepatitis C virus ribonucleic acid (HCV RNA), but viral hepatitis serologies was non-reactive for hepatitis B core antibody (HBcAB), hepatitis B surface antigen (HBsAg), hepatitis B surface antibody (HBsAb), hepaitis C virus antibody (HCV-AB), hepatitis E virus (HEV immunoglobulin G)-IgG and HEV-IgM, but was reactive for hepatitis A virus (HAV) IgM and IgG, despite prior immunity to HAV two years ago in May 2017 when the patient was only reactive for HAV-IgG and non-reactive for HBcAB, HBsAg, HBsAb and HCV-AB.  Supportive treatment was started. The patient's hospital stay was complicated by fulminant liver failure and hepatorenal syndrome. The patient was not a candidate for liver transplant due to continued alcohol use. On last day, prior to expiration date, the patient's lab tests showed ALT at 39, AST at 35, total bilirubin a 55.04, direct bilirubin at more than 14.00, INR at 3.11 and alkaline phosphatase at 90. The patient pursued hospice care and later expired. This case was considered as suspected vaccination failure since time to onset was unknown. This case was considered as serious due to death, vaccination failure and hospitalization. The authors commented "Immunity to HAV occurs after exposure to its antigen (Ag) confirmed by a positive IgG. Vaccination should offer lifelong immunity. T-cells play a main role in Ag presentation, cytokine induction and B cell differentiation. However, patients with a compromised immune system often experience T-cell dysfunction, hindering a proper immune response. Immunocompromised states, such as HIV infection, affect seroconversion rates after vaccination. One study showed 4% of patients with HAV infection were HIV positive and 55% were previously vaccinated. Our patient was negative for HIV but had a history of liver cirrhosis. The liver is the first organ in contact with the HAV Ag, delivered from the gut via the portal vein. Liver macrophages prevent systemic spread of Ag and hepatocytes synthesize complement. Both are essential for a robust immune response. This case highlights the risk of reinfection with HAV in cirrhotic patients, even with prior immunization. We suggest consideration for booster immunization in this population similar to that suggested for HIV patients".      Lab Comments: The patient's vital signs were normal. Polymerase chain reaction (PCR) did not detect hepatitis B virus deoxyribonucleic acid (HBV DNA) and hepatitis C virus ribonucleic acid (HCV RNA), but viral hepatitis serologies was non-reactive for hepatitis B core antibody (HBcAB), hepatitis B surface antigen (HBsAg), hepatitis B surface antibody (HBsAb), hepaitis C virus antibody (HCV-AB), hepatitis E virus (HEV immunoglobulin G)-IgG and HEV-IgM, but was reactive for hepatitis A virus (HAV) IgM and IgG, despite prior immunity to HAV two years ago in May 2017 when the patient was only reactive for HAV-IgG and non-reactive for HBcAB, HBsAg, HBsAb and HCV-AB. On last day in 2019, prior to expiration date, the patient's lab tests showed ALT at 39, AST at 35, total bilirubin a 55.04, direct bilirubin at more than 14.00, INR at 3.11 and alkaline phosphatase at 90; Reported Cause(s) of Death: Death NOS