Acute encephalopathy with human parvovirus B19 infection in hereditary spherocytosis

Human parvovirus B19 infection in hospitalized patients suspected of infection with pathogenic microorganism

Background

Human parvovirus B19 (HPV B19) is a single-stranded DNA virus. The detection rate of HPV B19 in the blood of healthy blood donors using PCR technology was reported to be 6.323/100000. However, that among hospitalized patients suspected of being infected with a pathogenic microorganism is unknown.

Methods

A retrospective analysis was conducted on 2,182 high-throughput NGS results for 1,484 inpatients admitted to the First Affiliated Hospital of Zhengzhou University from January 2020 to October 2021 who were suspected of being infected with a pathogenic microorganism, as well as on clinical data of some HPV B19-positive patients.

Results

Human parvovirus B19 was detected in 39 samples from 33 patients. The positivity rate was 2.22% among patients and 1.78% among samples. HPV B19 was detected in 20 cerebrospinal fluid samples, 13 blood samples, 3 alveolar lavage fluid samples, 2 tissue samples, and 1 throat swab. Based on clinical symptoms and NGS results, 16 patients were diagnosed with HPV B19 infection. The number of HPV B19 sequences in these patients was greater than 6, and the patients showed common symptoms such as fever (14 cases), anemia (11 cases), and severe nervous system symptoms such as meningoencephalitis (9 cases) and Guillain-Barré syndrome with peripheral motor and sensory nerve axon damage (4 cases). All 16 patients had experienced events likely to lead to decreased immunity (11 had a history of trauma/surgery/major disease, 4 had a history of precursor infection, and 3 had used immunosuppressants) and 7 had a history of blood transfusion during hospitalization. After treatment with antiviral drugs (12 cases) and intravenous human immunoglobulin (3 cases), of the 16 patients, 14 patients improved.

Conclusion

The HPV B19 infection rate in hospitalized patients suspected of microbial infection was 2.22%. Most patients with HPV B19 infection had a history of low immunity and blood transfusion. HPV B19 could be detected in various bodily fluids and tissues (especially cerebrospinal fluid) using NGS. Patients with severe HPV B19 infection may have nervous system damage such as Guillain-Barré syndrome and meningoencephalitis. Early diagnosis using NGS and treatment with antiviral drugs and immunoglobulin can improve prognosis.

Neurological Manifestations Associated with Parvovirus B19 Infection in Immunocompetent Children: Case Series and Systematic Review

An increasing number of reports have described human parvovirus B19 infection in association with a variety of neurological manifestations, especially in children. This study assessed the clinical and laboratory outcomes found in a case series of immunocompetent children who tested positive for parvovirus B19 by qualitative polymerase chain reaction assays of cerebrospinal fluid, in a tertiary referral center in the western Brazilian Amazon. We screened 178 children with clinically diagnosed central nervous system infections (meningoencephalitis). Of these, five (2.8%) were positive for parvovirus B19. A literature review also presented herein identified a further 50 cases of parvovirus B19 with neurological manifestations. Thus, even if the classic signs of parvovirus B19 infection are absent, such as the well-known rash, children with signs of neurological infection should also be evaluated for parvovirus B19 infection.

Human Parvoviruses

Parvovirus B19 (B19V) and human bocavirus 1 (HBoV1), members of the large Parvoviridae family, are human pathogens responsible for a variety of diseases. For B19V in particular, host features determine disease manifestations. These viruses are prevalent worldwide and are culturable in vitro, and serological and molecular assays are available but require careful interpretation of results. Additional human parvoviruses, including HBoV2 to -4, human parvovirus 4 (PARV4), and human bufavirus (BuV) are also reviewed. The full spectrum of parvovirus disease in humans has yet to be established. Candidate recombinant B19V vaccines have been developed but may not be commercially feasible. We review relevant features of the molecular and cellular biology of these viruses, and the human immune response that they elicit, which have allowed a deep understanding of pathophysiology.

Evidence of canine parvovirus transmission to a civet cat (Paradoxurus musangus) in Singapore

Cross-species transmission can often lead to deleterious effects in incidental hosts. Parvoviruses have a wide host range and primarily infect members of the order Carnivora. Here we describe juvenile common palm civet cats (Paradoxurus musangus) that were brought to the Singapore zoo and fell ill while quarantined. The tissues of two individual civets that died tested PCR-positive for parvovirus infection. Phylogenetic analysis revealed this parvovirus strain falls in a basal position to a clade of CPV that have infected dogs in China and Uruguay, suggesting cross-species transmission from domestic to wild animals. Our analysis further identified these viruses as genotype CPV-2a that is enzootic in carnivores. The ubiquity of virus infection in multiple tissues suggests this virus is pathogenic to civet cats. Here we document the cross-species transmission from domestic dogs and cats to wild civet populations, highlighting the vulnerability of wildlife to infectious agents in companion animals.

Acute encephalitis and encephalopathy associated with human parvovirus B19 infection in children

Reports of neurologic manifestations of human parvovirus B19 (B19) infection have been on the rise. Acute encephalitis and encephalopathy is the most common, accounting for 38.8% of total B19-associated neurological manifestations. To date, 34 children with B19 encephalitis and encephalopathy have been reported, which includes 21 encephalitis and 13 encephalopathy cases. Ten (29%) were immunocompromised and 17 (39%) had underlying diseases. Fever at the onset of disease and rash presented in 44.1% and 20.6% of patients, respectively. Neurological manifestations include alteration of consciousness occurred in all patients, seizures in 15 (44.1%) patients, and focal neurologic signs in 12 (35.3%) patients. Anemia and pleocytosis in cerebrospinal fluid (CSF) occurred in 56.3% and 48.1% of patients, respectively. Serum Anti-B19 IgM (82.6%) and CSF B19 DNA (90%) were positive in the majority of cases. Some patients were treated with intravenous immunoglobulins and/or steroids, although an accurate evaluation of the efficacy of these treatment modalities cannot be determined. Nineteen (57.6%) patients recovered completely, 11 (33.3%) patients had some neurological sequelae and 3 (8.8%) patients died. Although the precise pathogenesis underlying the development of B19 encephalitis and encephalopathy is unclear, direct B19 infection or NS1protein of B19 toxicity in the brain, and immune-mediated brain injuries have been proposed.

Quantitation of human parvovirus B19 DNA in erythema infectiosum and aplastic crisis

Several publications concerning the methods of real-time PCR for human parvovirus B19 (B19V) have appeared and some case reports mention B19V DNA loads. However, no large-scale study quantitating levels of B19V DNA in common or representative B19V manifestations such as erythema infectiosum and aplastic crisis has been performed. Consequently, using the TaqMan PCR assay, the B19V load in a large sample of subjects with erythema infectiosum or aplastic crisis was quantitated. Sixty-five subjects in the acute phase of erythema infectiosum were involved, and in addition 22 serum samples from seven subjects with B19V-associated aplastic crisis complicating chronic hemolytic anemia were also analyzed. In the acute phase of erythema infectiosum the median B19V DNA load in the serum samples from the acute phase of erythema infectiosum was 7.63 × 10(5)  genomes/ml, (range from 4.48 × 10(3) to 8.31 × 10(6)  genomes/ml). The serum B19V DNA load during the acute phase of aplastic crisis complicating chronic hemolytic anemia was extremely high, that is 10(10) -10(13)  genomes/ml, and decreased gradually to around 10(5) genomes/ml over 1-2 months. Although all subjects followed an almost uniform and typical clinical course of erythema infectiosum, there was a large individual variation of B19V DNA loads, that is differences of over 1,000 times. Extremely high B19V loads were observed in subjects with aplastic crisis. This study is the first large scale report of studies of the B19V DNA loads in subjects with erythema infectiosum and aplastic crisis, the most common and significant clinical manifestations by B19V infections.

Neurological aspects of human parvovirus B19 infection: a systematic review

Parvovirus B19 has been linked with various clinical syndromes including neurological manifestations. However, its role in the latter remains not completely understood. Although the last 10 years witnessed a surge of case reports on B19-associated neurological aspects, the literature data remains scattered and heterogeneous, and epidemiological information on the incidence of B19-associated neurological aspects cannot be accurately extrapolated. The aim of this review is to identify the characteristics of cases of B19-associated neurological manifestations. A computerized systematic review of existing literature concerning cases of B19-related neurological aspects revealed 89 articles describing 129 patients; 79 (61.2%) were associated with CNS manifestations, 41 (31.8%) were associated with peripheral nervous system manifestations, and 9 (7.0%) were linked with myalgic encephalomyelitis. The majority of the cases (50/129) had encephalitis. Clinical characteristic features of these cases were analyzed, and possible pathological mechanisms were also described. In conclusion, B19 should be included in differential diagnosis of encephalitic syndromes of unknown etiology in all age groups. Diagnosis should rely on investigation of anti-B19 IgM antibodies and detection of B19 DNA in serum or CSF. Treatment of severe cases might benefit from a combined regime of intravenous immunoglobulins and steroids. To confirm these outcomes, goal-targeted studies are recommended to exactly identify epidemiological scenarios and explore potential pathogenic mechanisms of these complications. Performing retrospective and prospective and multicenter studies concerning B19 and neurological aspects in general, and B19 and encephalitic syndromes in particular, are required. © 2014 The Authors. Reviews in Medical Virology published by John Wiley & Sons, Ltd.

Persistent adeno-associated virus 2 and parvovirus B19 sequences in post-mortem human cerebellum

We previously reported in a large cohort (N = 104) of post-mortem tissues the detection of both the non-pathogenic adeno-associated virus (AAV2) in approximately 13% and the pathogenic human parvovirus B19 (B19) in approximately 42% of human brains, particularly the dorsolateral prefrontal cortex. Multiple animal parvoviruses target the developing cerebellum (CBLM) resulting in hypoplasia and ataxia, but very little is known about the human parvoviruses and their ability to infect or cause disease in the CBLM. We have now confirmed in the above cohort the presence of AAV2 and B19 sequences in the CBLM. Our results show that approximately 27% and approximately 70% of human CBLM are positive by nested polymerase chain reaction for AAV2 and B19 sequences, respectively. We also document in a second cohort (N = 10) the presence of AAV2 (50%) and B19 (100%) sequences in the CBLM and correlate our results for B19 with studies from matched sera. Eighty percent (80%) of this cohort was positive for anti-B19 IgG, while none were IgM+, suggesting that most individuals had been previously infected with B19 but none acutely. To our knowledge, this study is the first to demonstrate that both AAV2 and B19 sequences are present at relatively high frequencies in the CBLM and are likely due to persistent rather than acute infection. Further studies will lead to insights into AAV2- and/or B19-CBLM interactions including mechanisms of infection, persistence, and possibly neuropathology, including cerebellar hypoplasia and ataxia.