Diagnosis of Peripheral Facial Palsy Associated with Parvovirus B19 Infection by Polymerase Chain Reaction

Human parvovirus B19 (PVB19) infection causes neurological manifestations, including encephalitis, meningitis, and neuropathy, but facial nerve palsy is rare. Moreover, no case of facial nerve palsy related to PVB19 infection that was diagnosed by PCR and serology has been reported. A 19-month-old boy without the medical history developed facial nerve palsy and was treated with prednisolone and valacyclovir. On the 19th day, erythema appeared on his body, and the PVB19-specific IgM and PVB19 DNA were detected in the serum, leading to the diagnosis of infectious erythema associated with PVB19 infection. This case indicates that PVB19 may be one of the causative agents of facial nerve palsy.

High-Resolution Structure of the Nuclease Domain of the Human Parvovirus B19 Main Replication Protein NS1

Two new structures of the N-terminal domain of the main replication protein, NS1, of Human Parvovirus B19 (B19V) are presented. This domain (NS1-nuc) plays an important role in the “rolling hairpin” replication of the single-stranded B19V DNA genome, recognizing origin of replication sequences in double-stranded DNA, and cleaving (i.e. nicking) single-stranded DNA at a nearby site known as the trs. One structure of NS1-nuc is solved to 2.4 Å and shows the positions of two bound phosphate ions. A second structure shows the position of a single divalent cation in the DNA nicking active site. The three-dimensional structure of NS1-nuc is well conserved between the two forms, as well as with a previously solved structure of a sequence variant of the same domain, however shown here at significantly higher resolution. Using structures of NS1-nuc homologues bound to single- and double-stranded DNA, models for DNA recognition and nicking by B19V NS1-nuc are presented which predict residues important for DNA cleavage and for sequence specific recognition at the viral origin of replication.

Disseminated Human Parvovirus B19 Infection Induced Multiple Organ Dysfunction Syndrome in an Adult Patient With Alcoholic Hepatitis Complicated by Hemolytic Anemia: A Case Report and Literature Review

BackgroundHuman parvovirus B19 (B19) can cause acute hepatitis and is attributed to the high mortality of alcoholic hepatitis (AH). B19 infection is generally self-healing in previously healthy people, but it can cause fatal effects in some high-risk groups and increase its virulence and infectivity. Disseminated B19 infection-induced multiple organ dysfunction syndrome (MODS) in patients with AH has not been reported yet. Here, we described B19 viremia in an adult patient with AH accompanied by hemolytic anemia (HA), leading to disseminated infection and secondary MODS, as well as self-limiting B19 infections in seven nurses caring for him. Meanwhile, we reviewed the literature on AH and B19 infection.Case PresentationA 43-year-old male patient with AH accompanied by HA was transferred to the Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, China, on March 31, 2021. After supportive treatment, his transaminase and bilirubin levels were reduced, but his anemia worsened. He received a red blood cell (RBC) infusion on April 9 for hemoglobin (Hb) lower than 6 g/dl. On April 13, he suddenly had a high fever. Under empirical anti-infection, his high fever dropped and maintained at a low fever level; however, his anemia worsened. On April 25, he was transferred to the medical intensive care unit (MICU) due to severe pneumonia, acute respiratory distress syndrome (ARDS), acute aplastic crisis (AAC), and hemophagocytic syndrome (HPS), which were subsequently confirmed to be related to B19 infection. After methylprednisolone, intravenous immunoglobulin (IVIG), empirical anti-infection, and supportive treatment, the lung infection improved, but hematopoietic and liver abnormalities aggravated, and systemic B19 infection occurred. Finally, the patient developed a refractory arrhythmia, heart failure, and shock and was referred to a local hospital by his family on May 8, 2021. Unfortunately, he died the next day. Fourteen days after he was transferred to MICU, seven nurses caring for him in his first two days in the MICU developed self-limiting erythema infectiosum (EI).ConclusionsB19 infection is self-limiting in healthy people, with low virulence and infectivity; however, in AH patients with HA, it can lead to fatal consequences and high contagion.