Successful intravenous immunoglobulin therapy in 3 cases of parvovirus B19-associated chronic fatigue syndrome.

Three cases of chronic fatigue syndrome (CFS) that followed acute parvovirus B19 infection were treated with a 5-day course of intravenous immunoglobulin (IVIG; 400 mg/kg per day), the only specific treatment for parvovirus B19 infection. We examined the influence of IVIG treatment on the production of cytokines and chemokines in individuals with CFS due to parvovirus B19. IVIG therapy led to clearance of parvovirus B19 viremia, resolution of symptoms, and improvement in physical and functional ability in all patients, as well as resolution of cytokine dysregulation.

Association of acute parvovirus B19 infection with new onset of acute lymphoblastic and myeloblastic leukaemia.

AIMS: To investigate the association of acute parvovirus B19 infection with new onset of acute lymphoblastic and myeloblastic leukaemia. METHODS: Cerebrospinal fluid (CSF) samples from patients with acute myelogenous leukaemia (AML) at diagnosis (n = 2) and acute lymphoblastic leukaemia (ALL) at diagnosis (n = 14) were analysed for parvovirus B19 DNA by means of nested polymerase chain reaction. In addition, samples from patients with benign intracranial hypertension (BIH) (n = 10) and hydrocephalus (n = 13) were tested as controls. RESULTS: Four leukaemia cases were positive-common ALL (n = 2), null cell ALL (n =1), and M7 AML (n = 1)-whereas all controls were negative (Yates corrected chi(2) value, 3.97; p = 0.046; odds ratio, 16.92; confidence interval, 1.03 to 77.18). All four patients were significantly anaemic, but none was encephalitic or had evidence of central nervous system leukaemia. In three of these patients, serum tumour necrosis alpha, interferon gamma, interleukin 6, granulocyte-macrophage colony stimulating factor (range, 34.93-3800.06 pg/ml), and macrophage chemoattractant protein 1 were detectable. All of these four patients carried at least one of the HLA-DRB1 alleles, which have been associated with symptomatic parvovirus B19 infection. CONCLUSION: Erythroid suppression and immune cell proliferation are both associated with B19 infection and may also be important in the pathogenesis of acute leukaemia.

Antibodies to parvovirus B19 non-structural protein are associated with chronic but not acute arthritis following B19 infection.

OBJECTIVE: To determine the incidence and significance of antibodies to the parvovirus B19 non-structural (NS1) protein in B19-infected persons during acute infection and convalescence. METHODS: The B19 NS1 protein was expressed in SF9 cells using the baculovirus expression system and was used to prepare immunofluorescence slides. These were used in a fluorescent antibody test to determine anti-B19 NS1 IgG in a well-characterized cohort of 53 persons at the time of acute B19 infection and again after a follow-up period of 26-85 months. Results were examined for statistical significance by the use of Fisher's exact test. RESULTS: NS1 antibodies were detected in five of 32 persons with acute B19 infection (four with arthritis) and 10 of 53 persons with past B19 infection (six with chronic arthritis and two with chronic arthritis and chronic fatigue syndrome). Regarding the correlation of NS1 antibodies and arthritis, at the time of acute infection four of 24 persons with arthritis had NS1 antibodies detected compared with one of eight persons with any other symptoms (P: = 1). During convalescence, eight of 20 persons with chronic arthritis had NS1 antibodies compared with two of 33 with symptoms of any other category (all except one were asymptomatic) (P: = 0.007). All 10 patients with NS1 antibodies during convalescence had arthritis during acute infection, which persisted in eight persons until the time of follow-up. CONCLUSION: Antibodies to parvovirus B19 NS1 protein are associated with chronic but not with acute arthritis after B19 infection.