Anda Kadiša, Zaiga Nora-Krūkle, Simons Švirskis, Pēteris Studers, Irute Girkontaite, Aivars Lejnieks and Modra Murovska
Rheumatoid arthritis (RA) is a chronic autoimmune disease that causes erosive changes and ankylosis of joints and may cause internal injuries. Osteoarthritis (OA) is a degenerative process of the articular cartilage. However, inflammatory mediators may play a pivotal role in the initiation and perpetuation of the OA process. It is necessary to continue to study possible factors that may promote the development of the disease. The goal of this study was to evaluate the frequency and activity stage of parvovirus B19 (B19V) and persistent human herpes virus (HHV)-6 and HHV-7 infection in RA and OA patients, and healthy persons, in relation to cytokine levels and presence or absence of viral infections. RA patients with active B19V infection had the highest levels of tumour necrosis factor alpha (TNF-α), which may contribute to the development of RA. In the case of OA, the TNF-α level was higher in patients with active persistent B19V infection, suggesting that B19V reactivation affects also OA. Interleukin (IL)-6, IL-10 and metalloproteinase (MMP)-9 levels were higher in RA patients with latent HHV-6/-7 infection in comparison with active HHV-6/-7 infection, whereas in OA patients levels of all studied cytokines were very variable, ranging from low to high but without significant differences. This suggests that also latent HHV-6 and -7 viral infections can promote development of RA.
Anda Vilmane, Inga Ziemele, Santa Rasa, Anna Terentjeva, Modra Murovska, Dace Gardovska, Yung-Cheng Lin and Zaiga Nora-Krūkle
Lower respiratory tract infection (LRTI) is the major cause of morbidity and mortality of children in the world. In addition to respiratory syncytial virus, influenza virus types A and B, parainfluenza types 1, 2 and 3, and adenoviruses, several new respiratory viruses associated with LRTI were discovered in the 21st century. These are metapneumovirus, coronaviruses NL63 and HKU1, parainfluenza virus type four and human bocavirus one (HBoV1). HBoV1 was discovered in 2005 and is considered as the fourth most prevalent respiratory virus worldwide. However, the high frequency of co-infections detected together with HBoV1 raises doubt about whether HBoV1 is a true pathogen or just a bystander. This is the first study aimed to determine the presence of HBoV1 and 18 other respiratory viruses in nasopharyngeal aspirates (NPA) of children with LRTI in Latvia. Using multiplex real-time polymerase chain reaction method, the HBoV1 genomic sequence was detected in 60.0% of NPA samples, showing that HBoV1 prevalence is high among children with LRTI in Latvia. HBoV1 mono-infection was revealed in 6.67%. The most common co-infections associated with HBoV1 were rhinovirus, adenovirus, respiratory syncytial virus A and B, metapneumovirus, and enterovirus.
Anda Kadiša, Zaiga Nora-Krūkle, Svetlana Kozireva, Simons Svirskis, Pēteris Studers, Valērija Groma, Aivars Lejnieks and Modra Murovska
Rheumatoid arthritis (RA) is a chronic systemic autoimmune inflammatory disease affecting joints and causing symmetrical chronic progressive aseptic synovitis and erosive-destructive changes. Viruses and viral infections are considered to be the main risk factors for autoimmune disease development (especially for individuals with genetic predisposition). The goal of this study was to evaluate the frequency of HHV-6 and HHV-7 persistent infection and its activity phase in RA and osteoarthritis (OA) patients, and healthy persons. We examined also the influence of HHV-6 and -7 infections on RA activity, aggressiveness, radiographical stage, and frequency of complications as well as the presence of HHV-6 infection markers in synovial fluid and synovial tissues of RA joints of affected patients. Despite the lack of significant correlation between frequency of persistent single HHV-6, single HHV-7, and concurrent HHV-6 and HHV-7 infection and RA clinical course, we found that both active and latent HHV-6 and/or HHV-7 infection increased RA activity and progression in several clinical and laboratory parameters. Regarding the severity of the course of RA, we observed also a high prevalence of RA complications in the patient group with active single HHV-6 infection and also a more severe radiographical stage in RA patients with active concurrent HHV-6 and HHV-7 infection. Moreover, viral infection markers were found in synovial fluid and synovial tissues of affected joints of RA patients. This suggests that HHV-6 and/or HHV-7 infection has effect on the disease clinical course, but virus reactivation may be a consequence of immunosuppressive treatment.
Inga Ziemele, Man Xu, Anda Vilmane, Santa Rasa-Dzelzkalēja, Klaus Hedman, Maria Söderlund-Venermo, Dace Gardovska, Zaiga Nora-Krūkle and Modra Murovska
Since its discovery in 2005, human bocavirus 1 (HBoV1) has globally been one of the most common respiratory viruses. It is currently accepted that HBoV1 is a pathogen, causing upper and lower respiratory tract infections (LRTIs) in children. However, due to the prolonged HBoV1 DNA shedding from the upper airways and the subsequent high rate of co-detections with other respiratory viruses, the interpretation of positive polymerase chain reaction results is challenging. The aim of this study was to identify acute HBoV1 infections by the presence of HBoV1-specific IgM and IgG measured by competition enzyme immunoassay, to elucidate the induction of Th1/Th2 cytokines, and to describe the clinical characteristics associated with acute HBoV1 infection in hospitalised children less than five years of age with LRTI. HBoV1 IgM was detected in 19/102 (18.6%) and IgG in 66/102 (64.7%) patients. HBoV1 IgM was most frequently found in patients aged 13 to 24 months. Pneumonia and acute wheezing were the most common clinical diagnoses among HBoV1 IgM positive patients. The seroprevalence of HBoV1-specific IgG increased with age, reaching 85% by the age of five years. INF-γ, IL-4, IL-5, and IL-10 were observed to be higher in patients with acute HBoV1 infection.
Zaiga Nora-Krūkle, Santa Rasa, Anda Vilmane, Sabīne Grāvelsiņa, Mārtiņš Kālis, Inga Ziemele, Milda Naciute, Sigita Petraitiene, Diana Mieliauskaite, Migle Klimantaviciene, Irute Girkontaite, Hsin-Fu Liu, Jih-Hui Lin, Yung-Cheng Lin, Hsiu-Chuan Chan, Dace Gardovska and Modra Murovska
Human bocavirus 1 (HBoV1) is a parvovirus recently found to be a possible aetiologic agent of acute respiratory disease in children. We conducted the first clinical and molecular study on this virus in Latvia (LV) and Lithuania (LT). The aim of the study was to determine the occurrence of HBoV1 in respiratory tract samples taken from hospitalised children with acute respiratory tract infections in LV and LT. In total 186 children with age one to 50 months, and who fulfilled criteria of acute respiratory tract infection, including lower respiratory tract infections, with or without fever, were included in this study. A nasopharyngeal aspirate was obtained from each patient on admission. DNA was isolated and polimerase chain reaction (PCR) performed targeting the HBoV1 NS1sequence. HBoV1 positive samples were sequenced and phylogenetic analysis was performed. HBoV1 sequence was detected in 42 (32%) of 130 LV and in 8 (14%) of 56 LT samples. In LV the majority of patients with HBoV1 infection were observed in February while in LT in October. The phylogenetic tree for HBoV1 indicated that isolates of HBoV1 cluster closely and include almost all of the isolates in this study. HBoV1 is common in Latvia and Lithuania and might be a significant pathogen that contributes to acute respiratory tract infections in children.