人微小病毒B19感染所致肝损害19例临床分析

目的探讨B19病毒感染所致肝损害的临床表现、实验室检查特点及治疗与转归。方法对人微小病毒B19感染患者19例的临床资料进行回顾性分析。结果在人微小病毒B19感染的19例患者,主要症状有乏力(12例)、黄疸(10例)、脾肿大(10例),伴有发热(10例)、皮疹(6例)及肌肉关节疼痛(6例),有6例伴有如下疾病或并发症:如妊娠(1例)、急性肝功能衰竭(2例)、精神分裂症(1例)、急性骨髓停滞(1例)和肺炎(1例)。以血清天门冬氨酸氨基转移梅(AST)升高为主,黄疸大多数表现为轻到中度,容易出现凝血酶原活动度(PTA)下降,但胆碱脂酶(CHE)下降不明显。经积极对症支持治疗,肝功能等各项指标正常后治愈出院。人微小病毒B19可致肝功能受损,导致急性肝炎或急性重型肝炎。结论对临床上非甲～戊型肝炎病人,应注意检查血清抗B19病毒IgM。该病毒感染是一个急性或亚急性过程,呈良性经过,有自愈倾向。     

Multiple pseudo-cellulitis plaques and Koplick's sign: a particular form of parvovirus B19 primo-infection in adults

INTRODUCTION: clinical presentation which seems to be more specific of this infection. EXEGESIS: A 35-year-old woman, 12 weeks pregnant, presented with a primary infection of parvovirus B19. The clinical presentation was characterized by pseudo-cellulitis plaques of the buttocks and the vulva, buccal enanthema with ulcerations and Koplick spot. CONCLUSION: This is the second observation which describes such cutaneous and mucosal manifestations associated with parvovirus B19 infection. This kind of clinical presentation should be systematically reported to become well known by the physicians as erythema infectiosum of fifth disease or "gloves and socks" syndrome.     

Parvovirus B19 infection and systemic lupus erythematosus: Activation of an aberrant pathway?

Parvovirus B19 infection has been associated with a variety of rheumatic manifestations/diseases, mainly rheumatoid arthritis, vasculitis and systemic lupus erythematosus (SLE). B19 infection may simulate both clinical and laboratory features of SLE, presenting either as a potential first time diagnosis of SLE or as an exacerbation of previously established disease. The similarities in both clinical and serological features of parvovirus infection and SLE at presentation may hinder the differential diagnosis between these two conditions. Hence, parvovirus B19 infection mimicking SLE usually fulfils <4 ACR criteria for SLE, rarely includes cardiac or renal involvement or presents with haemolytic anaemia, and is usually associated with short-lived, low titers of autoantibodies. Rarely, cases of multisystemic involvement solely attributed to a recent parvovirus B19 infection have been reported, rendering early accurate diagnosis of particular importance and justifying the screening for evidence of parvovirus B19 involvement in newly diagnosed cases of SLE, especially the ones with abrupt onset of symptoms along with cases of SLE flares. This review describes basic features of parvovirus B19 structure and pathogenicity and expands on the parvo-associated auto-immune manifestations particularly in relation to SLE-mimicking or SLE-triggering reported cases. The proposed mechanisms for viral-induced pathologic autoimmunity are discussed with emphasis on emerging data regarding the aberrant expression and localization of autoantigens and their potential implication in alternatively activated immunological cascades.     

Rheumatoid purpura in adults and parvovirus B19 infection: fortuitous association or parvovirus B19-induced vasculitis?

INTRODUCTION: Henoch-Schoenlein purpura has been reported to be associated with parvovirus B19 infection, particularly in children and rarely in adults. We report the case of a 42-year-old patient presenting with this association. EXEGESIS: A 42-year-old patient was admitted to our medical center because of lower limb purpura. Henoch-Schoenlein purpura diagnosis was confirmed on histological findings (kidney biopsy) and concomitantly parvovirus B19 infection was proved by serological test (IgM+). Association of Henoch-Schoenlein purpura and parvovirus B19 infection has already been described. However, none of the reported studies demonstrated clearly the link between these two diseases. With regard to this observation, we wonder about the systematic use of the parvovirus B19 serological test in patients presenting first Henoch-Schoenlein purpura. Indeed, parvovirus B19-induced vasculitis is habitually controlled with intravenous immunoglobulins. CONCLUSION: A prospective study should explore the link between Henoch-Schoenlein purpura and primary parvovirus B19 infection. Moreover, we should evaluate intravenous immunoglobulins' efficacy in Henoch-Schoenlein purpura associated with active parvovirus B19 infection in order to improve the prognosis of this disease.     

Association of parvovirus B19 infection with acute icteric hepatitis in adults

Infection by human parvovirus B19 is widespread and can be associated with a wide range of different pathologies and clinical manifestations. However, parvovirus B19 infection associated with hepatitis or hepatic dysfunction in adults is rarely reported. We describe two cases of acute icteric hepatitis associated with parvovirus B19 infection in adults.     

Fifth (human parvovirus) and sixth (herpesvirus 6) diseases

Fifth (erythema infectiosum) and sixth (roseola infantum) diseases are common rash illnesses of childhood that have long been recognized in clinical medicine. The discovery of the viruses that cause these illnesses has revealed relationships with other syndromes. Primary infection with the agent of erythema infectiosum, human parvovirus B19, is associated with transient aplastic crisis in hemolytic anemia, arthropathy in adults, chronic anemia in immunocompromised patients, and nonimmune fetal hydrops in pregnant women. The only documented illness associated with primary infection with human herpesvirus 6 is roseola or exanthema subitum in young children. However, reactivated infections in adults and immunocompromised patients may be associated with serious illness such as encephalitis/encephalopathy, and bone marrow suppression leading to transplant failure or graft-versus-host disease. Diagnostic studies for both viruses have been limited, although reliable serologic tests for human parvovirus B19 have recently become available. Diagnosis of human herpesvirus 6 remains problematic, because current tests cannot differentiate primary from reactivated disease. This is more of an issue for the putative relationship of these viruses to more chronic conditions, such as rheumatologic disease for human parvovirus B19 and multiple sclerosis for human herpesvirus 6. The relationship between the viruses and these conditions remains controversial, and better diagnostic tests and further information on viral pathogenesis for both viruses are required in order to make a reliable judgment in this regard.     

Lupus-like presentation of parvovirus B19 infection

OBJECTIVES: To describe 2 cases of parvovirus B19 (B19) infection mimicking systemic lupus erythematosus (SLE) and to identify all cases of SLE imitated by and/or associated with B19 in the medical literature. METHODS: A computer-assisted (PubMed) search of the medical literature from 1975 to 2003 was performed using the following key words: parvovirus, B19, SLE, lupus, antibodies, auto-immunity. RESULTS: Thirty-eight patients were identified: 35 women, 3 men; mean age = 28.8 years. Clinical manifestations were as follows: fever (24 patients); articular involvement (36 patients); cutaneous lesions (28 patients); lymphadenopathy (9 patients); hepato- and/or splenomegaly (6 patients); serositis (6 patients); renal involvement (4 patients); cerebral impairment (10 patients). Cytopenia was observed in 23 cases. Antinuclear antibodies were detected in 34 patients, anti-double-stranded DNA antibodies in 20 patients, anti-Sm antibodies in 4 patients, antinuclear ribonucleoprotein antibodies in 5 patients, anti-Ro-SSA antibodies in 4 patients, anti-La-SSB antibodies in 4 patients, and anticardiolipin and/or anti-beta2-glycoprotein I antibodies in 8 patients. Hypocomplementemia was found in 15 of 26 patients. In 19 cases, the B19 infection had a self-limiting course. In 6 cases, B19 infection occurred in a context of previously established SLE, simulating SLE exacerbation. In 6 observations, symptoms persisted several months after the viral infection. In 7 cases, the exact relationship between SLE and B19 could not be determined. CONCLUSIONS: B19 infection may present a clinical and serological tableau making it difficult to distinguish between a viral infection and the first episode of SLE. Although B19 may modulate the clinical and biological features of rheumatic disease, studies in large series do not support a causative role for B19 in the pathogenesis of SLE.     

Infection with parvovirus B19

Human parvovirus B19 is common and widespread. Major manifestations of B19 infection are transient aplastic crisis, erythema infectiosum, hydrops fetalis, acute and chronic rheumatoid-like arthropathy and, in the immunocompromised host, chronic or recurrent bone marrow infection. Less common presentations include skin eruptions, isolated cytopenias, vasculitis, hepatitis, and neuropathies. Increasing awareness of the clinical manifestations of B19 infection makes parvovirus B19 an emerging virus. B19 may persist in healthy or immunocompromised individuals. B19 has been suggested as a candidate agent in rheumatic diseases.     

Antiphospholipid antibodies in pediatric and adult patients with rheumatic disease are associated with parvovirus B19 infection

OBJECTIVE: To show a possible association between parvovirus B19 infection and the presence of antiphospholipid antibodies (aPL) in patients with rheumatic diseases. METHODS: Serum samples obtained from 88 children with various forms of juvenile rheumatic disease and from 40 adults with systemic lupus erythematosus, the antiphospholipid syndrome, or other rheumatic disease, who had previously been tested and shown to be positive for IgG aPL, were analyzed for the presence of B19 DNA, for antibodies against the B19 viral proteins VP1, VP2, and NS1, and for IgG aPL (anticardiolipin, anti-beta(2)-glycoprotein I, and antiphosphatidylserine). As controls, serum samples obtained from 135 children with noninflammatory bone diseases or growth retardation were also analyzed. RESULTS: Twenty-four (27%) of the 88 children with rheumatic diseases had detectable amounts of IgG aPL. Fourteen (58%) of these 24 IgG aPL-positive patients showed IgG against VP1/VP2 and viral genomes, indicating the presence of acute (2 patients) or persistent (12 patients) infection. Past parvovirus B19 infection was identified in 7 (29%) of 24 IgG aPL-positive children, as indicated by VP1/VP2-specific IgG in the absence of viral DNA. Three (12%) of 24 IgG aPL-positive children had not been infected with B19. Sixty-nine (51%) of 135 control children displayed VP1/VP2-specific IgG. Three (2%) of these 135 children were IgG aPL positive (2 children had past parvovirus B19 infection, and 1 was negative for parvovirus B19). Analysis of the parvovirus B19 status of 40 adult IgG aPL-positive patients showed that 33 (83%) were anti-IgG VP1/VP2-positive, and viral DNA was detected in 11 patients (28%). Ten of these 11 viremic patients were in the subgroup of 28 IgG aPL-positive SLE patients. CONCLUSION: Antiphospholipid antibodies are preferentially found in serum of children with juvenile idiopathic arthritis who have been previously infected with parvovirus B19 and have established, persistent infection. Adult patients with IgG aPL positivity have a high incidence of persistent parvovirus B19 infection. We conclude that parvovirus B19 might be directly involved in the elicitation of autoimmune reactions partly mediated by aPL.     

Human parvovirus B19 infection in patients with systemic lupus erythematosus

OBJECTIVE: The clinical significance of the presence of B19 DNA in patients with SLE was studied. METHODS: Sera from 72 patients with systemic lupus erythematosus (SLE), 23 patients with rheumatoid arthritis (RA), 18 patients with Sj?gren's syndrome (SS), eight patients with Raynaud's phenomenon (RP), five patients with primary biliary cirrhosis (PBC), five patients with polymyositis (PM), four patients with erythema infectiosum (EI) and 22 normal controls were examined for parvovirus B19 (B19) infection by serological assays, nested PCR and Southern blotting. RESULTS: Parvovirus B19 DNA was detected in 17 of 72 patients with SLE and in three of four patients with EI, but not in patients with other systemic rheumatic diseases. Of the 17 patients with B19 DNA, only one had IgG anti-B19 antibody and two had IgM anti-B19 antibodies, whereas IgG and IgM anti-B19 antibodies were detected in 27 (49.1%) and 21 (38.2%) of 55 SLE patients without B19 DNA respectively. All sera from the patients with EI contained both IgG and IgM anti-B19 antibodies. B19 DNA was found more commonly in sera from SLE patients without anti-B19 antibodies than in those with anti-B19 antibodies (P<0.05). CONCLUSIONS: B19 infection in patients with SLE may be due to lack of anti-B19 antibodies because of either the immunocompromised nature of the host or the use of immunosuppressive drugs. There was a higher prevalence of hypocomplementaemia and RP in patients with parvovirus B19 viraemia than in those without parvovirus B19 viraemia.     

Parvovirus B19 infection in children with acute lymphoblastic leukemia is associated with cytopenia resulting in prolonged interruptions of chemotherapy.

BACKGROUND: Parvovirus B19 infection causes severe cytopenia and can mimic a leukemic relapse or therapy-induced cytopenia in patients with hematologic malignancies. We evaluated the complications of parvovirus B19 infection, including delays in the scheduled course of chemotherapy, in children with acute lymphoblastic leukemia (ALL). METHODS: Consecutive bone marrow samples were collected from 117 children with ALL and were analyzed for parvovirus B19 DNA by polymerase chain reaction. Clinical and laboratory data were collected from the Nordic Childhood Leukemia Registry and from medical records. RESULTS: Among the 117 children with ALL, 18 (15%) were found to be parvovirus B19 DNA positive. The infection was suspected on clinical grounds in only 1 of these 18 patients. Patients with viremia at diagnosis or during therapy for infection had lower viral loads (median viral load, 7 x 10(4) copies/mL) than did those who became viremic during maintenance therapy (median viral load, 2 x 10(8) copies/mL). The former group also had fewer clinical complications. Indeed, when parvovirus B19 DNA was present during the maintenance treatment, the number of complications (including cytopenia) increased, causing significantly longer periods without chemotherapy (median duration without chemotherapy, 59 days vs. 30 days; P < or = .05) and a higher number of blood transfusions (P = .018) in parvovirus B19 DNA-positive patients than in parvovirus B19 DNA-negative patients. CONCLUSIONS: Children with ALL who were infected with parvovirus B19 became cytopenic, leading to reduced treatment intensity and to complications during treatment. Screening for parvovirus B19 DNA by quantitative polymerase chain reaction in pediatric patients with ALL and unexplained cytopenia is suggested.     

Acute parvovirus B19 infection in pregnant women—An analysis of serial samples by serological and semi-quantitative PCR techniques

Summary The serological and virological course of parvovirus B19 infection was followed in 14 women who suffered symptomatic or subclinical acute infection during pregnancy. Serial serum samples from the patients were tested for IgG and IgM antibodies and the levels of parvovirus B19 DNA were monitored using a semi-quantitative PCR assay. In addition, the outcome of the pregnancies was documented by clinical information and by testing cord blood for parvovirus B19 specific antibodies as well as for parvovirus B19 DNA by PCR. Levels of IgG antibodies rose steadily within 2 months of infection and in some cases began to decline at the end of pregnancy. IgM antibodies were usually detected for at least 2 months and persisted for as long as 9 months in one case. Viral DNA was detectable for at least 8 weeks following infection and semi-quantitative analysis revealed a gradual reduction in virus load during the viraemic phase of infection. There were no apparent differences in the course of antibody development and duration of viraemia in symptomatic versus subclinical infections.     

Persistent B19 parvovirus infection in patients infected with human immunodeficiency virus type 1 (HIV-1): a treatable cause of anemia in AIDS

OBJECTIVE: To determine the role of B19 parvovirus in red cell aplasia of patients infected with human immunodeficiency virus type 1 (HIV-1). DESIGN: Uncontrolled clinical trial, with assay of serum, peripheral blood cells, and bone marrow for virus using DNA hybridization and immunocytochemistry techniques; these assays were then correlated with clinical findings, results of immunoassays for antivirus antibodies, and with immunoglobulin (Ig) therapy. SETTING: Government medical referral center, and university and private hospitals. PATIENTS: Seven patients with pure red cell aplasia and serologic evidence of infection with HIV-1. MEASUREMENTS AND MAIN RESULTS: All patients had giant pronormoblasts in the bone marrow (present in transient aplastic crisis caused by acute B19 parvovirus infection). High concentrations of B19 parvovirus were demonstrated in sera, in several cases in samples separated by weeks or months. Viral DNA and capsid protein were present in the bone marrow of three patients studied, and active viral replication was detected by southern analysis. There was no antivirus IgG in capture immunoassay and no or very low levels of antivirus IgM. The patients did not have symptoms of fifth disease, the illness caused by this virus in immunologically normal persons. Six patients were treated with a regimen of intravenous commercial immunoglobulin. In all cases, this therapy resulted in rapid reduction in serum virus concentrations and full recovery of erythropoiesis. Relapses in two cases were predicted by DNA hybridization studies, and these cases were successfully retreated. CONCLUSIONS: The B19 parvovirus is a remediable cause of severe chronic anemia in HIV-infected patients. Recognition of and therapy for parvovirus in this population will avoid erythrocyte transfusion and should prevent transmission of the virus to other persons, including immunosuppressed persons and women of child-bearing age.     

Infection and musculoskeletal conditions: Viral causes of arthritis

Several viruses cause postinfectious arthritis. The disease is a typical manifestation of arthritogenic alphaviruses, rubella virus and human parvovirus B19. In addition, arthritis is not uncommon after infection by HIV, cytomegalovirus, hepatitis B virus, hepatitis C virus, or Epstein-Barr virus (EBV). Also prolonged arthritis may result from viral infections, particularly with alphaviruses and human parvovirus B19. Viruses such as EBV and B19 may have significant roles in initiating chronic arthropathies, which in some cases may be indistinguishable from rheumatoid arthritis.     

Frequency of recent parvovirus infection in patients examined for acute reactive arthritis. A study with combinatorial parvovirus serodiagnostics

OBJECTIVE: To determine the causative role of human parvovirus B19 as a preceding infection in patients examined for acute reactive arthritis (ReA). METHODS: Sixty adult patients with acute arthritis were screened for evidence of triggering infections. In all patients, cultures of stool specimens and of Chlamydia trachomatis in urethra/cervix, and/or bacterial serology were studied. The timing of primary infection of human parvovirus B19 was determined by measurement in serum of VP2-IgM, VP2-IgG, epitope-type specifity of VP2-IgG, and avidity of VP1-IgG. RESULTS: Median time from onset of joint symptoms to the rheumatological consultation was five weeks (range 1-62). Of the 60 patients, 35 fulfilled the diagnostic criteria for ReA; in the remaining, the diagnosis was unspecified arthritis (UA). Thirty-six patients had antibodies for the B19 virus. Occurrence of these antibodies did not differ significantly between ReA and UA groups (P = 0.61). Of these 36 patients, 34 had a pre-existing immunity to the B19 virus. Of the two other patients, one had rash and self-limiting polyarthritis with serological evidence of B19 primary infection, and the other had arthritis of the lower extremities with serological evidence of a convalescence period after the B19 primary infection. The latter patient also had antibodies to Yersinia, with a clinical picture typical for ReA. CONCLUSION: In patients examined for acute ReA, the frequency of recent B19 virus infection was 3.3% (2 out of 60). The diagnostic utility of the presented methodology, by using a single serum sample, was evident.     

Different patterns of disease manifestations of parvovirus B19-associated reactive juvenile arthritis and the induction of antiphospholipid-antibodies

Children with rheumatic oligo- and polyarthritis frequently establish persistent parvovirus B19 infections, which may be associated with the production of antiphospholipid antibodies. Reported in this paper are the data of five girls with polyarticular rheumatic diseases of different types and persistent parvovirus B19 infection associated in four cases with the presence of antibodies against phospholipids. Clinical parameters, virus load, and antiphospholipid-IgG levels were determined during an observation period up to 92 months. In two patients, erythema infectiosum preceded the development of arthritis and B19 viremia persisted. Two other girls showed antibodies against parvoviral structural proteins at time of the manifestation of the rheumatic disease. Subsequent samples also revealed persistent B19 infection. In the fifth patient, parvovirus B19-specific IgG antibodies were detected for the first time after 120 months of progressing disease at an age of 11 1/2 years. Five years later, quantitative polymerase chain reaction (PCR) revealed viral DNA. In a synovial tissue specimen subsequently obtained, parvovirus B19 structural proteins could be detected by immunohistochemistry. Three of five patients recovered completely without severe sequels. One patient is in remission under immunosuppressive therapy. The fifth patient suffers from progressive erosions despite intensive therapeutical efforts. In consequence, parvovirus B 19 should generally be taken into consideration as a trigger of various forms of juvenile arthritis and persistence of infection should be evaluated.     

B19 virus--a pathogenic human parvovirus

B19 virus is the first human virus to be shown to be a member of the parvovirus genus. This review is concerned with the diseases associated with B19 virus, their nature, pathogenesis and diagnosis. The virus was discovered by chance in blood donors but has been shown to be a common infection of childhood. Infection may be asymptomatic or associated with mild, non-specific symptoms. The most common specific clinical manifestation is an erythematous rash illness which often has the classical features of erythema infectiosum. Often, however, it is described simply as rubelliform and only laboratory tests can distinguish B19 and rubella virus infections. Joint involvement is the most common complication of B19 virus infection occurring especially in adult females. It often involves the joints of the hands and wrists, clears rapidly in most patients but may persist for months or years in a few. B19 virus is also the principle cause of the transient aplastic crisis which complicates chronic haemolytic anaemia. This has been demonstrated repeatedly in sickle cell anaemia and hereditary spherocytosis and in individual cases of other haemolytic anaemias. The pathogenesis of the aplastic crisis is related to the ability of B19 virus to infect and damage early erythroid progenitor cells. Volunteer studies in normal individuals have demonstrated that this is a regular event occurring about a week after infection via the respiratory tract. Rash illness and joint involvement occur 7 to 10 days later and are presumably immune mediated. Diagnosis of B19 virus infection can be achieved by detection of the viraemia (aplastic crisis) or by detection of virus specific IgM antibody (all diseases).(ABSTRACT TRUNCATED AT 250 WORDS)     

Pure red cell aplasia in a lung transplant patient

Aplastic anemia secondary to infection by parvovirus B19 is normally an extremely rare problem in patients with no prior history. However, the presence of certain risks, such as receiving chronic immunosuppressant therapy, may facilitate its appearance. Very few cases have been published concerning red cell aplasia due to parvovirus B19 infection in patients receiving a transplanted lung. We report the case of a 24-year-old woman with cystic fibrosis who had received a double lung transplant. The patient developed red cell aplasia secondary to parvovirus B19 infection; severe anemia requiring multiple transfusions. Five days of intravenous immunoglobulin therapy resolved the anemia. We discuss the difficulty of serological diagnosis in such cases, the importance of using techniques that identify the virus and taking measures that may prevent recurrence.     

Donor‐transmitted parvovirus infection in a kidney transplant recipient presenting as pancytopenia and allograft dysfunction

Abstract: Parvovirus B19 is a nonenveloped single‐stranded DNA virus that commonly causes a benign childhood infection typically manifesting as a ‘slapped‐cheek’ rash. In immunodeficient hosts, this infection can cause persistent anemia and occasionally pancytopenia. Recently, direct renal involvement has been reported in renal transplant recipients leading to various forms of glomerulopathy and allograft dysfunction. Most cases are primary infections and are donor transmitted through the transplanted organ. Clinical and virological response to intravenous immunoglobulin (Ig) is usually excellent. We describe a case of donor‐transmitted parvovirus infection in a 23‐year‐old male who received his first cadaver renal transplant. The patient had an uncomplicated postoperative course with immediate graft function. Eight weeks after transplantation, he presented with fever, polyarthralgia, pancytopenia, and allograft dysfunction. Serological studies revealed elevated IgM titers against parvovirus B19. A renal biopsy was performed, which showed no evidence of acute rejection but with moderate degree of tubular damage. Parvovirus B19 viral DNA was detected in the renal tissue via polymerase chain reaction (PCR). The patient received a 10‐day course of intravenous Ig (400 mg/kg/day) with excellent response. His blood count normalized and the allograft improved to baseline function. The incidence of parvovirus infection in renal transplant patients is probably underestimated, because patients are not routinely screened for it and anemia and/or pancytopenia in these patients are often ascribed to immunosuppressive drugs. Because this infection is treatable, we conclude that parvovirus B19 infection should be actively considered in transplant patients presenting with pancytopenia and allograft dysfunction.     

Unusual localisation of chronic arthropathy in lumbar facet joints after parvovirus B19 infection

Human parvovirus B19 infection may be responsible for acute and chronic arthropathy. We present the case of a woman, who developed a severe chronic parvovirus B19 infection with persistence of DNA parvovirus B19, which was detected in the serum by polymerase chain reaction (PCR). After intravenous immunoglobulin administration she noted a disappearance of the general symptoms and the virus became indetectable by PCR in the serum. However, 1 month later back pain appeared. Magnetic resonance imaging showed bilateral effusions of the apophyseal joints of the lumbar spine (L4–L5). Spine involvement is rarely described during acute or chronic parvovirus B19 infection. In this case it was not possible to determine whether the facet joint arthropathy was reactive or due to persistent articular infection, or induced by immunoglobulin therapy. Received: 4 April 2001 / Accepted: 5 February 2002