Case report: risk of virus infection after accidental blood inoculation from a multi-infected AIDS patient.

Infections caused by blood-borne viruses such as hepatitis B and C and the human immunodeficiency virus (HIV) are associated commonly with needlestick injuries, especially in a hospital setting. A prospective investigation was conducted on a medical doctor who suffered an accidental needlestick injury during blood collection from a patient with AIDS. The patient's blood contained 195,000 copies of HIV RNA, 1 × 10(6) IU hepatitis C virus (HCV) RNA, and >10(7) copies of parvovirus B19 DNA per 1 ml plasma. It was positive for cytomegalovirus virus and evidence of a resolved hepatitis B virus (HBV) infection was found. HCV viremia was detected in the physician 15 days later and was not resolved by seroconversion after 57 days. HIV infection was not transmitted, possibly because of the immediate use of anti-HIV prophylactic drugs after exposure. Parvovirus B19 infection was presumably prevented by pre-existing specific antibodies in the patient. Considering that many HIV carriers are coinfected with hepatitis B and C viruses, this case report support the knowledge that the risk of HCV transmission from a patient with AIDS is greater than that of HIV.

Recent publications in medical microbiology and immunology: a retrospective.

A look back is done to some clinical and basic research activities recently published in medical microbiology and immunology. The review covers clinical experiences and in vitro experiments to understand the emergency, pathogenicity, epidemic spread, and vaccine-based prevention of avian and swine-origin flu. Some new developments and concepts in diagnosis, (molecular) epidemiology, and therapy of AIDS, viral hepatitis C, and herpesvirus-associated diseases are outlined. Regulation of immune system has been discussed in a special issue 2010 including some aspects of CNS affections (measles). Mycobacterial infection and its prevention by modern recombinant vaccines have reached new interest, as well as new concepts of vaccination and prophylaxis against several other bacteria. Adaptation to host niches enables immune escape (example brucella) and determines virulence (example N. meningitidis). Chlamydia pneumoniae, previously considered to trigger atherosclerosis, is hypothetically associated to Alzheimer disease, while CMV, another putative trigger of atherosclerosis, gains evidence of oncomodulation in CNS tumor diseases. In terms of globalization, exotic virus infections are increasingly imported from southern countries.

Selection of a highly invasive neuroblastoma cell population through long-term human cytomegalovirus infection.

The human cytomegalovirus (HCMV) is suspected to increase tumour malignancy by infection of cancer and/or stroma cells (oncomodulation). So far, oncomodulatory mechanisms have been attributed to the presence of HCMV and direct action of its gene products on cancer cells. Here, we investigated whether the prolonged presence of HCMV can result in the irreversible selection of a cancer cell population with increased malignancy. The neuroblastoma cell line UKF-NB-4 was long-term (200 passages) infected with the HCMV strain Hi91 (UKF-NB-4(Hi)) before virus eradication using ganciclovir (UKF-NB-4(HiGCV)). Global gene expression profiling of UKF-NB-4, UKF-NB-4(Hi) and UKF-NB-4(HiGCV) cells and subsequent bioinformatic signal transduction pathway analysis revealed clear differences between UKF-NB-4 and UKF-NB-4(Hi), as well as between UKF-NB-4 and UKF-NB-4(HiGCV) cells, but only minor differences between UKF-NB-4(Hi) and UKF-NB-4(HiGCV) cells. Investigation of the expression of a subset of five genes in different chronically HCMV-infected cell lines before and after virus eradication suggested that long-term HCMV infection reproducibly causes specific changes. Array comparative genomic hybridisation showed virtually the same genomic differences for the comparisons UKF-NB-4(Hi)/UKF-NB-4 and UKF-NB-4(HiGCV)/UKF-NB-4. UKF-NB-4(Hi) cells are characterised by an increased invasive potential compared with UKF-NB-4 cells. This phenotype was completely retained in UKF-NB-4(HiGCV) cells. Moreover, there was a substantial overlap in the signal transduction pathways that differed significantly between UKF-NB-4(Hi)/UKF-NB-4(HiGCV) and UKF-NB-4 cells and those differentially regulated between tumour tissues from neuroblastoma patients with favourable or poor outcome. In conclusion, we present the first experimental evidence that long-term HCMV infection can result in the selection of tumour cell populations with enhanced malignancy.

Adaptation of cancer cells from different entities to the MDM2 inhibitor nutlin-3 results in the emergence of p53-mutated multi-drug-resistant cancer cells.

Six p53 wild-type cancer cell lines from infrequently p53-mutated entities (neuroblastoma, rhabdomyosarcoma, and melanoma) were continuously exposed to increasing concentrations of the murine double minute 2 inhibitor nutlin-3, resulting in the emergence of nutlin-3-resistant, p53-mutated sublines displaying a multi-drug resistance phenotype. Only 2 out of 28 sublines adapted to various cytotoxic drugs harboured p53 mutations. Nutlin-3-adapted UKF-NB-3 cells (UKF-NB-3(r)Nutlin(10 µM), harbouring a G245C mutation) were also radiation resistant. Analysis of UKF-NB-3 and UKF-NB-3(r)Nutlin(10 µM) cells by RNA interference experiments and lentiviral transduction of wild-type p53 into p53-mutated UKF-NB-3(r)Nutlin(10 µM) cells revealed that the loss of p53 function contributes to the multi-drug resistance of UKF-NB-3(r)Nutlin(10 µM) cells. Bioinformatics PANTHER pathway analysis based on microarray measurements of mRNA abundance indicated a substantial overlap in the signalling pathways differentially regulated between UKF-NB-3(r)Nutlin(10 µM) and UKF-NB-3 and between UKF-NB-3 and its cisplatin-, doxorubicin-, or vincristine-resistant sublines. Repeated nutlin-3 adaptation of neuroblastoma cells resulted in sublines harbouring various p53 mutations with high frequency. A p53 wild-type single cell-derived UKF-NB-3 clone was adapted to nutlin-3 in independent experiments. Eight out of ten resulting sublines were p53-mutated harbouring six different p53 mutations. This indicates that nutlin-3 induces de novo p53 mutations not initially present in the original cell population. Therefore, nutlin-3-treated cancer patients should be carefully monitored for the emergence of p53-mutated, multi-drug-resistant cells.

Seroepidemiology of parvovirus B19 in the Frankfurt am Main area, Germany: evaluation of risk factors.

BACKGROUND: Parvovirus B 19 is a virus that is distributed by respiratory droplets. It is known to be an initiator of erythema infectiosum (children's fifth disease), with erythroblasts being the target cells of infection. In case of vertically transmission, hydrops fetalis has been documented. OBJECTIVE: Parvovirus B19 seroprevalence was investigated in serum samples routinely collected from patients who had been admitted to the University Hospital in Frankfurt a. M., Germany. Patients were classified in different groups in order to analyze parovirus B19 seroprevalences in terms of risk factors. MATERIALS AND METHODS: Between June 2007 and March 2010, a total of 2,197 serum samples were analyzed for parvovirus B19-immunoglobulin G using an enzyme-linked immunosorbent assay. The study population included six groups of patients, namely, patients suffering from haemophilia, malignant disease, immunodeficiency diseases, common gynecological ailments, pregnant women and children with malignant diseases. RESULTS: Of the 2,197 serum samples, 1,383 contained antibodies to parvovirus B19 (62.9%). The overall seroprevalence in adults (20 to ≥60 years of age) was 71%. Gradually rising prevalences were recorded in children/adolescents with increasing age. We found a positive serostatus in 54.9% of adult patients with malignant disease, in 64.2% of patients with haemophilia (1 to ≥60 years), in 66.7% of patients under immunosuppression with various drugs (1 to ≥60 years) and in 41.7% of oncological patients aged 1-19 years. Of the pregnant women (aged 15-49 years), 71.1% were seropositive. CONCLUSION: The seroprevalence of parvovirus B19 in patients admitted to the University Hospital in Frankfurt a.M. was, on average, lower than that among the general population in Germany. Infection among patients in specific risk groups did not spread more than that in age-matched non-selected patients, with the exception of the group of immunocompromised patients.

Reconstitution of cytomegalovirus specific T cells after pediatric allogeneic stem cell transplantation: results from a pilot study using a multi-allele CMV tetramer group.

BACKGROUND: Recovery of cytomegalovirus (CMV)-specific T cell mediated immunity after allogeneic hematopoietic stem cell transplantation (SCT) is critical for protection against CMV disease. Tetramer-based technologies have been shown to be a sensitive tool in the enumeration of specific T cells, but have the disadvantage of HLA-restriction of the peptides. PATIENTS AND METHODS: In this pilot study, we tested the feasibility of a panel of 6 CMV-specific tetrameric HLA/CMV-peptide complexes to enumerate CMV-specific CD8 +T cells (CTLs). The reconstitution of CMV-specific CTLs was assessed in 16 children in the first year after allogeneic SCT (median age, 8 years). RESULTS: The presented assay covered more than 85% of our patients transplanted in the last 3 years. During CMV-reactivation, all 4 of the 16 analyzed patients with a high virus-load showed less than 10 CMV-specific CTLs/microl; out of these, three had not any detectable CMV-CTLs. On the other hand, five of the children with less than 10 CMV-specific CTLs/microl did not develop CMV reactivation. When enumeration of T cells was performed by means of different tetrameric HLA/CMV-peptide complexes simultaneously, the numbers of CMV-specific CTLs cells widely differed according to the HLA-type. CONCLUSIONS: Our pilot study suggests that enumeration of CMV-specific T cells by means of a panel of 6 tetramers might be a useful tool in the risk assessment for CMV reactivation in the majority of patients undergoing allogeneic SCT, but future trials have to evaluate whether this method is appropriate in tailoring antiviral therapy in the individual patient.

Valproic acid inhibits adhesion of vincristine- and cisplatin-resistant neuroblastoma tumour cells to endothelium.

Drug resistance to chemotherapy is often associated with increased malignancy in neuroblastoma (NB). In pursuit of alternative treatments for chemoresistant tumour cells, we tested the response of multidrug-resistant SKNSH and of vincristine (VCR)-, doxorubicin (DOX)-, or cisplatin (CDDP)-resistant UKF-NB-2, UKF-NB-3 or UKF-NB-6 NB tumour cell lines to valproic acid (VPA), a differentiation inducer currently in clinical trials. Drug resistance caused elevated NB adhesion (UKF-NB-2(VCR), UKF-NB-2(DOX), UKF-NB-2(CDDP), UKF-NB-3(VCR), UKF-NB-3(CDDP), UKF-NB-6(VCR), UKF-NB-6(CDDP)) to an endothelial cell monolayer, accompanied by downregulation of the adhesion receptor neural cell adhesion molecule (NCAM). Based on the UKF-NB-3 model, N-myc proteins were enhanced in UKF-NB-3(VCR) and UKF-NB-3(CDDP), compared to the drug naïve controls. p73 was diminished, whereas the p73 isoform deltaNp73 was upregulated in UKF-NB-3(VCR) and UKF-NB-3(CDDP). Valproic acid blocked adhesion of UKF-NB-3(VCR) and UKF-NB-3(CDDP), but not of UKF-NB-3(DOX), and induced the upregulation of NCAM surface expression, NCAM protein content and NCAM coding mRNA. Valproic acid diminished N-myc and enhanced p73 protein level, coupled with downregulation of deltaNp73 in UKF-NB-3(VCR) and UKF-NB-3(CDDP). Valproic acid also reverted enhanced adhesion properties of drug-resistant UKF-NB-2, UKF-NB-6 and SKNSH cells, and therefore may provide an alternative approach to the treatment of drug-resistant NB by blocking invasive processes.

Valproic acid induces extracellular signal-regulated kinase 1/2 activation and inhibits apoptosis in endothelial cells.

The histone deacetylase (HDAC) inhibitor valproic acid (VPA) was recently shown to inhibit angiogenesis, but displays no toxicity in endothelial cells. Here, we demonstrate that VPA increases extracellular signal-regulated kinase 1/2 (ERK 1/2) phosphorylation in human umbilical vein endothelial cells (HUVEC). The investigation of structurally modified VPA derivatives revealed that the induction of ERK 1/2 phosphorylation is not correlated to HDAC inhibition. PD98059, a pharmacological inhibitor of the mitogen-activated protein kinase kinase 1/2, prevented the VPA-induced ERK 1/2 phosphorylation. In endothelial cells, ERK 1/2 phosphorylation is known to promote cell survival and angiogenesis. Our results showed that VPA-induced ERK 1/2 phosphorylation in turn causes phosphorylation of the antiapoptotic protein Bcl-2 and inhibits serum starvation-induced HUVEC apoptosis and cytochrome c release from the mitochondria. Moreover, the combination of VPA with PD98059 synergistically inhibited angiogenesis in vitro and in vivo.

Infection of cultured intestinal epithelial cells with severe acute respiratory syndrome coronavirus.

To identify a model for the study of intestinal pathogenesis of severe acute respiratory syndrome (SARS) we tested the sensitivity of six human intestinal epithelial cell lines to infection with SARS coronavirus (SARS-CoV). In permissive cell lines, effects of SARS-CoV on cellular gene expression were analysed using high-density oligonucleotide arrays. Caco-2 and CL-14 cell lines were found to be highly permissive to SARS-CoV, due to the presence of angiotensin-converting enzyme 2 as a functional receptor. In both cell lines, SARS-CoV infection deregulated expression of cellular genes which may be important for the intestinal pathogenesis of SARS.

Cytomegalovirus infection blocks apoptosis in cancer cells.

Recent pathological findings reveal a higher frequency of human cytomegalovirus (HCMV) in tumor cells from different tumors compared with surrounding tissues. Experimental investigations suggest possible supportive effects of HCMV for tumor development and progression. One HCMV effect on tumor cells is the inhibition of apoptosis, leading to the promotion of tumor cell survival. Decreased sensitivity to treatment-induced tumor cell death is a major reason for failure of anticancer chemotherapy. HCMV infection interferes with both the intrinsic and extrinsic cellular apoptosis pathways. HCMV promotes cell survival signaling influencing the tumor suppressor p53 and its relative p73, and stimulates the antiapoptotic Ras/Raf/MEK/Erk- and PI-3K-signaling pathways. Antiapoptotic effects mediated by HCMV are inhibited by antiviral treatment in cell culture. Therefore, a better understanding of the influence of HCMV infection on tumor cell apoptosis might translate into improved anti-cancer therapy.

Acute retinal necrosis six years after herpes simplex encephalitis: an elusive immune deficit suggested by insufficient test sensitivity.

A patient presented with acute retinal necrosis of the left eye. Demonstration of herpes simplex virus (HSV) DNA in the aqueous humour confirmed the diagnosis. Negative results of HSV type-specific antibody tests based on gG antigens suggested a primary HSV infection. However, the patient had a past history of laboratory-confirmed herpes simplex encephalitis 6 years ago. Using antibody tests based on whole viral lysate antigens, he was seropositive from the onset, and immunoblot testing confirmed a lack of anti-gG reactivity. To be able to assess whether this might be related to the apparent inability of his immune system to suppress clinically symptomatic HSV infection, serial samples were tested by an HSV neutralisation test and a whole-blood flow cytometric assay to determine the frequency of HSV-specific CD4 lymphocytes. However, this did not yield evidence of obvious immunodeficiency; the patient reacted similarly to known positive controls by both assays. Although type-specific HSV serological tests based on gG are generally more specific than those based on whole viral lysate antigens, they have a somewhat lower sensitivity, as a certain percentage of HSV-infected individuals do not develop antibodies against gG, and others may suffer a secondary loss of anti-gG reactivity. Thus there is a risk of missing individual infected patients. Unless this potential problem is recognised, serious consequences might possibly result. We therefore urge virologists and clinicians to exercise great care if highly specific antibody assays based on recombinant proteins are employed.

Primary cytomegalovirus infection in an outpatient setting--laboratory markers and clinical aspects.

BACKGROUND: Occasionally, primary cytomegalovirus (CMV) infection may give rise to more or less severe clinical illness in immunocompetent adults. We retrospectively analyzed cases of acute CMV infection in medical outpatients. PATIENTS AND METHODS: Over a 6-year period, we identified 22 patients with a febrile illness and hepatitis suffering from primary CMV infection. This was diagnosed on the basis of a strongly positive CMV IgM antibody test result and/or CMV IgG seroconversion. Clinical features as well as relevant laboratory results were analyzed. We also tested available samples for CMV glycoprotein B-specific antibodies and CMV IgG avidity and analyzed results of Epstein-Barr virus (EBV)-specific antibody assays. In addition, current age-specific CMV IgG seroprevalence rates were determined using 9,870 routine patient samples. RESULTS: At presentation, all patients complained of malaise and fever higher than 38 degrees C, and many also complained of cephalgia. Most patients who underwent abdominal ultrasonography had an enlargement of the spleen. Most patients had a relative lymphocytosis but only three had a mild leukocytosis. C-reactive protein was only slightly elevated in 13 patients; all 22 patients had elevated levels of alanine aminotransferase (ALT) and lactate dehydrogenase (LDH). Half the patients reported travel to areas outside western Europe, mostly to tropical and subtropical areas, within 3 weeks before onset of illness. Primary CMV infection was confirmed by negative anti-gB antibody test results and the absence of high-avidity CMV antibodies. In contrast, despite past EBV infection demonstrated by positive anti-EBNA-1 results, 15 out of 21 patients tested for EBV markers had positive or nonspecific IgM test results. The overall CMV IgG seroprevalence rate in the routine samples was 64.4%, with marked age-dependent increases. CONCLUSION: CMV is a relevant differential diagnosis in feverish illnesses accompanied by hepatitis in otherwise healthy adults, about 40% of whom are CMV-naïve. Half our patients seem to have acquired their CMV infection abroad, so that a diagnosis of CMV infection needs to be taken into account in travelers, in addition to infectious illnesses more commonly considered in this context, such as dengue or hepatitis A. For diagnosis, both CMV and EBV antibody studies should be performed and the inclusion of assays able to demonstrate past infection is helpful for achieving a definite diagnosis.

Prions and orthopedic surgery.

Prions are a novel class of infectious agents that cause subacute encephalopathy in man and animals as human Creutzfeldt-Jakob disease (CJD), sheep scrapie and bovine spongiform encephalopathy (BSE). Previously, prions were shown to be transmitted by neuro- and ophthalmosurgical measures and by application of brain-derived therapeutic hormones. Recently, prions have been detected in blood specimens of experimentally infected monkeys indicating a principal threat to transfusion medicine, furthermore in human or bovine materials used in reconstructive surgery. In this article the risk of prion transmission from the surgeon to the patient or vice versa during (orthopedic) surgery is reevaluated including the issues of blood transfusion. This is accomplished based on recent epidemiologic findings and biometric calculations on the spread of prions in animals and humans as well as in terms of experimental data on artificially contaminated medical materials and devices. The overall risk of prion transmission in orthopedic surgery is considered very low if adequately prepared and sterilized materials and devices are used.

Viral zoonoses - a threat under control?

Despite intensive research and considerable effort to eradicate infectious diseases, modern medicine has failed to control many infectious diseases which have been thought to be easy to overcome with advances in medical science and technology. In fact, infectious diseases remain a dominant feature in public health considerations for the 21st century. Some infectious agents already known to be pathogenic have gained increasing importance in recent decades due to changes in disease patterns. Furthermore, many new, previously unknown infectious agents with a high pathogenic potential have been identified. Nearly all of these emergent disease episodes have involved zoonotic or species-jumping infectious agents. The complex interaction of factors like environmental and ecological changes, social factors, decline of health care, human demographics and behaviour influences the emergence of re-emergence of such diseases. Viruses, especially RNA viruses with their ability to adapt quickly to changing environmental conditions, are among the most prominent examples of emerging pathogens. In this review, we present the important examples of zoonotic viruses and discuss the factors playing a key role in the emergence and resurgence of these diseases.

Herpes zoster guideline of the German Dermatology Society (DDG).

Varicella zoster virus (VZV) causes varicella (chickenpox), remains dormant in dorsal root and cranial nerve ganglia and can be reactivated as a consequence of declining VZV-specific cellular immunity leading to herpes zoster (shingles). Patients older than 50 years of age affected by herpes zoster may suffer a significant decrease of quality of life. These patients and immunocompromised individuals are at increased risks for severe complications, involving the eye, the peripheral and the central nervous system (prolonged pain, postherpetic neuralgia). Such complications occur with and without cutaneous symptoms. The German Dermatology Society (DDG) has released guidelines in order to guarantee updated management to anyone affected by herpes zoster. Diagnosis is primarily clinical. The gold standard of laboratory diagnosis comprises PCR and direct identification of VZV in cell cultures. Detection of IgM- and IgA-anti VZV antibodies may be helpful in immunocompromised patients. Therapy has become very effective in the last years. Systemic antiviral therapy is able to shorten the healing process of acute herpes zoster, to prevent or to alleviate pain and other acute and chronic complications, particularly, when given within 48 h to a maximum of 72 h after onset of the rash. Systemic antiviral therapy is urgently indicated in patients beyond the age of 50 years and in patients at any age with herpes zoster in the head and neck area, especially in patients with zoster ophthalmicus. Further urgent indications are severe herpes zoster on the trunk and on the extremities, herpes zoster in immunosuppressed patients and in patients with severe atopic dermatitis and severe ekzema. Only relative indications for antiviral therapy exist in patients younger than 50 years with zoster on the trunk and on the extremities. In Germany acyclovir, valacyclovir, famciclovir and brivudin are approved for the systemic antiviral treatment of herpes zoster. These compounds are all well tolerated by the patients and do not differ with regard to efficacy and safety. Brivudin has a markedly higher anti-VZV potency than oral acyclovir, valacyclovir and famciclovir and thus offers a simpler dosing regimen. It must be given only once daily during 7 days in comparison to three and five times dosing per day of valacyclovir, famciclovir and acyclovir, respectively. Brivudin is an antiviral agent with no nephrotoxic properties, which is an advantage when compared to acyclovir. The most important aim of therapy of herpes zoster is to achieve painlessness. Appropriately dosed analgesics in combination with a neuroactive agent (i.e. amitriptylin) are very helpful when given together with antiviral therapy. The additive therapy with corticosteroids may shorten the degree and duration of acute zoster pain, but has no essential effect on the development of postherpetic neuralgia, which is a very difficult condition to treat. Thus early presentation to a pain therapist is recommended in specific cases.

Polyomavirus viruria in bone marrow transplant recipients: lack of correlation with clinical symptoms.

BACKGROUND: Human polyomavirus (HPV) infection is controversially discussed as a factor influencing the outcome of bone marrow transplantation (BMT). PATIENTS AND METHODS: Here we report on 62 patients undergoing BMT with clinical signs of urocystitis, such as micro- or macrohematuria with more or less severe dysuria. These patients were tested for the presence of HPV in urine specimens (n = 80) by transmission electron microscopy (TEM). RESULTS: HPV viruria was found in 35 patients (56%); 33 (94%) of them had hemorrhagic cystitis, whereas two (6%) were suffering from dysuria only. Among the patients with hemorrhagic cystitis, ten (30%) presented with macrohematuria, four (12%) with microhematuria and 19 (58%) with micro- or macrohematuria and severe dysuria. 26 of 27 HPV-negative patients (96%) showed hemorrhagic cystitis with either macrohematuria (n = 7) (26%) or microhematuria (n = 15) (56%). Four patients (15%) suffered from hematuria and dysuria, one patient (4%) from dysuria only. CONCLUSION: Although HPV-negative patients tended to present with less severe clinical symptoms, overall no statistically significant influence on the outcome of BMT was seen.