Anna Mania

Phylogeny and molecular evolution of the hepatitis C virus

The hepatitis C virus (HCV) is a globally prevalent human pathogen that causes persistent liver infections in most infected individuals. HCV is classified into seven phylogenetically distinct genotypes, which have different geographical distributions and levels of genetic diversity. Some of these genotypes are endemic and highly divergent, whereas others disseminate rapidly on an epidemic scale but display lower variability. HCV phylogeny has an important impact on disease epidemiology and clinical practice because the viral genotype may determine the pathogenesis and severity of the resultant chronic liver disease. In addition, there is a clear association between the HCV genotype and its susceptibility to antiviral treatment. Similarly to other RNA viruses, in a single host, HCV exists as a combination of related but genetically different variants. The whole formation is the actual target of selection exerted by a host organism and antiviral therapeutics. The genetic structure of the viral population is largely shaped by mutations that are constantly introduced during an error-prone replication. However, it appears that genetic recombination may also contribute to this process. This heterogeneous collection of variants has a significant ability to evolve towards the fitness optimum. Interestingly, negative selection, which restricts diversity, emerges as an essential force that drives HCV evolution. It is becoming clear that HCV evolves to become stably adapted to the host environment. In this article we review the HCV phylogeny and molecular evolution in the context of host-virus interactions.

Cat-scratch disease: a wide spectrum of clinical pictures.

The aim of this review is to present an emerging zoonotic disease caused by Bartonella henselae. The wide spectrum of diseases connected with these bacteria varies from asymptomatic cases, to skin inflammation, fever of unknown origin, lymphadenopathy, eye disorders, encephalitis and endocarditis. The reservoirs of B. henselae are domestic animals like cats, guinea pigs, rabbits and occasionally dogs. Diagnosis is most often based on a history of exposure to cats and a serologic test with high titres of the immunoglobulin G antibody to B. henselae. Most cases of cat-scratch disease are self-limited and do not require antibiotic treatment. If an antibiotic is chosen, however, azithromycin has been shown to speed recovery.

Neurologic Complications Caused by Epstein-Barr Virus in Pediatric Patients

We retrospectively analyzed the medical documentation of 194 children infected with Epstein-Barr virus. The diagnosis was based on clinical symptoms and the presence of the viral capsid antigen IgM antibody. Patients with severe neurologic complications also underwent neurologic examination, magnetic resonance imaging (MRI), and electroencephalography (EEG). There were 2 peaks in incidence of infection; the first one in young children aged 1 to 5 years represented 62.0% of cases. The second peak (24.6% of patients) occurred in teenagers. Febrile seizures were confirmed in 3.1% of affected children younger than 5 years and headaches in 24.2% patients, mostly older children. Ten children presented severe, neurologic complications: meningoencephalitis, acute encephalitis, acute cerebellitis, transverse myelitis, and myeloradiculitis. Our study identified a variety of Epstein-Barr virus–related neurologic complications. Epstein-Barr virus should be routinely tested for when a child presents with an apparent neuroinfection as it is a common pathogen that can induce a wide variety of signs and symptoms.

Pulmonary presentation of Toxocara sp. infection in children

INTRODUCTION The aim of this study was to investigate the associations between radiological findings, blood eosinophilia, hyperimmunoglobulinemia E and G and Toxocara seropositivity in Polish children with newly diagnosed pulmonary infiltration. MATERIAL AND METHODS We retrospectively analyzed the documentation of 119 patients, aged 1 to 18 years (mean age: 7.21 ± 4.82), who were seropositive in Toxocara sp. antibodies. In all cases, peripheral blood eosinophils and leukocyte counts, serum total IgE, IgG levels and specific IgG antibodies against excretory and secretory Toxocara sp. antigens were measured at the first presentation. After the confirmation of seropositivity, all children had a routine radiological examination. RESULTS In the documentation of 23 children (mean age 3.58 ± 2.63 years) we found abnormalities in the radiological examination of their lungs. Fifteen children who had abnormalities in radiological findings presented clinical respiratory complaints such as chronic cough, wheezing, asthma and haemoptysis. Eight children were asymptomatic. The analysis of peripheral eosinophils and leukocyte number, the level of IgE and specific anti-Toxocara IgG presented significantly higher values in children with radiological lesions than in children who had correct radiology. The concentrations of total IgG and gamma globulins were not significantly different. In 10 patients CT showed irregular round nodules with and without halo ranging from 1 to 13 mm. The number of nodules varied from a single lesion to multiple, disseminated ones. All nodules were located in peripheral areas of the lungs. None of them were found in the central areas. In 13 patients, CT images showed ground-glass opacities with ill-defined margins. None of the CT images presented lymphadenopathy and pleural effusion. CONCLUSION The pulmonary lesions in small children with high eosinophilia and hyperimmunoglobulinemia E could be related to toxocariasis and for this reason they are eligible to undergo therapy with prolonged observation for several months, rather than start invasive malignancy investigations.

Expression of pattern recognition receptors in liver biopsy specimens of children chronically infected with HBV and HCV

Pattern recognition receptors (PRRs) constitute a pivotal arm of innate immunity. Their distribution is widespread and not limited to cells of the immune system. Following our previous findings concerning the expression of Toll-like receptors (TLRs) 2, 3 and 4 in chronic viral hepatitis C of children, we wished to search for other PRRs, including other TLRs, NOD-like receptors (NLRs) and RIG-1-like helicase receptors (RLR) in infected hepatocytes. Liver biopsy fragments from ten children with chronic hepatitis B and C were used and two others in which hepatotropic virus infection was excluded. Frozen sections of liver samples were subjected to ABC immunohistochemistry (IHC) following incubation with a set of antibodies. Results of IHC findings were screened for correlation with clinical/laboratory data of patients. It was found that several PRRs could be shown in affected hepatocytes, but the incidence was higher in hepatitis C than in B. In hepatitis C, TLR1, 2, 4, NALP and RIG-1 helicase showed the most marked expression. In hepatitis B, TLR1, 3, 9, NOD1 and NALP expression were the most conspicuous. Expression PRRs in liver from hepatitis of unknown origin was much lower. It was also the case in cytospins from human hepatoma cell line. Several correlations between PRRs expression and clinical findings in patients could be shown by statistical exploration. In conclusion, this data suggests some role for PRRs in the pathogenesis of chronic viral hepatitis.

Clinical condition and transmission of coinfections with human cytomegalovirus in infants of HIV-1 infected mothers in the era of mother-to-child-transmission prophylaxis

BACKGROUND AND AIM The aim of the study was to evaluate the clinical state and the risk of coinfections in infants of HIV-1-infected women receiving MTCT prophylaxis. METHODS The study included 35 Polish infants of HIV-1-infected mothers diagnosed for congenital infections. Children were evaluated for HIV-1, HCMV and HCV infection by serological and molecular methods during following visits up to 18th month of life. None of the children received breast milk after birth. RESULTS HIV-1 infection was found in one child not receiving MTCT prophylaxis, one HCV infection was detected in another infant. HCMV-DNA in the urine was present in 13/35 children (37.14%) in the 10th day and 24/35 children (68.57%) at 4th week of life. The group of children managed with full and incomplete MTCT regimen did not differ in most clinical parameters. Children receiving MTCT prophylaxis were born more frequently as first children (p=0.045) and by cesarean section (p=0.047). HCMV-positive children receiving MTCT prophylaxis were had lower gestational age (p=0.03) and smaller head circumference (p=0.02). They were born more frequently as premature (0.02) and with low birth weight (0.02). Maternal cART and the use of protease inhibitors were not significantly associated with perinatal complications. No differences in CD4+ and CD8+ counts were noted between the group receiving full and incomplete MTCT protocol. CONCLUSIONS ARV used in MTCT preventive protocols is safe for infants although the risk of the transmission of HCMV coinfection is not reduced.

Human cytomegalovirus infection and clinical status of infants born to human immunodeficiency virus type 1 infected mothers

Objective. Human cytomegalovirus (HCMV) is one of the most common congenital infections worldwide and a frequent opportunistic infection that aggravates the condition of human immunodeficiency virus (HIV)-infected patients. The aim of the study was to evaluate the frequency and factors influencing HCMV infection among infants of HIV-positive women. Methods. The study included 35 infants born to HIV-1-infected mothers examined for congenital infections. Children were evaluated for human immunodeficiency virus type 1 (HIV-1), HCMV, and HCV infection by serological and molecular methods. Results. HIV-1 infection was found in one child whose mother did not receive antiretroviral treatment during pregnancy, and HCV infection in another infant. HCMV-DNA in the urine was present in 13/35 infants (37.14%) on the 10th day and 24/35 infants (68.57%) in the 4th week of life. The majority of HCMV-infected infants were asymptomatic, although they manifested microcephaly and low birth weight significantly more frequently (p = 0.006 and p = 0.02, respectively). Type HIV prophylaxis did not influence HCMV transmission. Conclusions. Although often asymptomatic, HCMV infection in infants born to HIV-infected mothers is frequent and may be associated with prematurity, low birth weight, and microcephaly. Diagnostic procedures in children of HIV-infected mothers should involve HCMV.

Clinical Picture and Liver Histology of Chronic Hepatitis C in Children

Background and Aim Chronic hepatitis C (CHC) is still a significant clinical problem because of not only a large proportion of infected individuals, but also unclear remote consequences of the disease. The aim of the study was to analyze the clinical course and the liver histology of CHC in children searching for potential influencing factors. Methods Sixty-eight children were enrolled into the study (mean, 13.34 [SD, 3.27] years). Medical records and a current clinical status of children were analyzed considering clinical symptoms, liver function tests, and qualitative and quantitative hepatitis C virus–RNA assay with genotype and liver histology. Results A parenteral route of infection concerned 98% of children; mean length of infection was 7.34 (SD, 4.03) years. Genotype 1a was found in 78% and 1b in 16.2% children. The history of malignancy was present in 74% of patients. The symptoms of liver cirrhosis with abnormal vein circulation were found in 2 children (3%). An increased alanine aminotransferase activity was detected in 62% of patients, whereas viral load less than 6 × 105 IU/mL was found in 56 children (82%). Histological evaluation of biopsy specimens showed moderate inflammatory activity (G 2) and fibrosis (S 2; mean, 2.0). Progression of fibrosis was proportional to the age at infection. Conclusions The clinical course of CHC is usually mild but may result in the liver cirrhosis during childhood. Transient or constant increased alanine aminotransferase activity is observed in majority of children. Inflammatory activity and fibrosis have moderate progression in children and are proportional to the age at infection.

Detection and Significance of Cytotoxic Cell Subsets in Biopsies of HCV-Infected Human Livers

AbstractChronic viral hepatitis C still remains the clinical challenge. Attempts of the immune system to cope with this infection are unsatisfactory. There is a conviction that the main site of interaction between virus (Hepatitis C virus, HCV) and immune system is in situ, i.e., in liver. Natural killer (NK) cells appeared relevant in the acute hepatitis. Less is known about the immune response in the chronic HCV infection. The aim of this study was to evaluate the prevalence of various cytotoxic cell subsets in chronic HCV+ liver tissue and to seek links between them and laboratory data of patients. Sections from paraffin blocks of liver biopsy tissues of HCV+ untreated patients were subjected to the reaction with antibodies vs. cytotoxic cell subsets and immunohistochemistry. Positive cells were searched in cellular infiltrates in portal areas and in liver parenchyma. They were classified on the “Yes” or “No” basis. Majority of liver biopsies exhibited cellular infiltrates in portal spaces and as single cells in liver parenchyma. Infiltrates consisted of CD8+ T cells, CD56+ NK ones, including CD158i+ and CD158b+. The latter were rarely seen. There were also granzyme B+ cells. The most abundant were NKG2D+ cells, much more common than NK CD56+ ones. It implied that NKG2D was also expressed on T cells. Prevalence of NKG2D+ cells correlated with high activity of liver enzymes such as alanine aminotransferase, aspartate aminotransferase and a greater histological severity of liver injury. NKG2D+ cells form the bulk of cells infiltrating HCV-infected human liver. Correlation of NKG2D+ cells with some laboratory parameters of patients suggests their role in hepatitis C pathogenesis.

Replikacja HCMV w surowicy krwi i moczu dzieci z cytomegalią wrodzoną

Streszczenie Wstep Zakazenia wewnątrzlonowe lub okoloporodowe ludzkim wirusem cytomegalii ( human cytomegalowirus – HCMV) mogą prowadzic do cytomegalii wrodzonej, charakteryzującej sie zespolem wad lub zaburzen wielonarządowych. Cel pracy Ocena czasu utrzymywania sie replikacji HCMV w surowicy krwi i w moczu u dzieci z cytomegalią wrodzoną. Material i metody Badaniem objeto 30 dzieci z cytomegalią wrodzoną. Rozpoznanie choroby ustalono na podstawie parametrow klinicznych, serologicznych (ocena przeciwcial antyHCMV IgM i antyHCMV IgG – test ELISA) oraz wirusologicznych (oznaczenie DNA HCMV w surowicy i moczu chorych, fragmentow kodujących tzw. antygen wczesny i poźny – metoda PCR). Ocene utrzymywania sie replikacji HCMV przeprowadzano przed i po terapii gancyklowirem, a nastepnie w okresie obserwacji trwającym od 6 miesiecy do 7,5 lat. Wyniki W momencie rozpoznania choroby u wszystkich pacjentow stwierdzono obecnośc ktoregoś z fragmentow DNA HCMV w surowicy krwi lub/i w moczu. Po pierwszej kuracji przeciwwirusowej u 13% dzieci z badanej grupy uzyskano poprawe zarowno parametrow klinicznych, serologicznych, jak i wirusologicznych. Eliminacje obu badanych fragmentow DNA HCMV (kodujące bialka MIE i pp65) z krwi uzyskano u 70% dzieci, z moczu u 27% dzieci. Czas utrzymywania sie wykladnikow replikacji HCMV w moczu pacjentow byl zdecydowanie dluzszy niz we krwi. Wnioski Ocena DNA HCMV we krwi i w moczu jest szczegolnie przydatna w diagnostyce zakazen wrodzonych HCMV, monitorowaniu przebiegu choroby oraz ustaleniu skuteczności terapii. Nie stwierdzono samoistnej eliminacji DNA HCMV z krwi lub/i moczu dzieci z cytomegalią wrodzoną, u ktorych nie uzyskano poprawy po leczeniu przeciwwirusowym.