[Clinical significance of IgM anti-HCV determination in chronic hepatitis C].

Background: In the majority of patients with acute viral hepatitis C the early antibody IgM anti-HCV in serum is positive. However, a substantial portion of the patients with chronic hepatitis C has also positive IgM anti-HCV as a sign of the continuing replication of the virus. The objective of the work was to assess the presence of IgM anti-HCV in patients with confirmed chronic hepatitis C, in subjects with HBsAg negative chronic hepatitis and in excluded blood donors.

Clinical importance of assessment of anti-HCV IgM antibodies in chronic hepatitis C.

In the majority of patients with acute hepatitis C the anti-HCV IgM antibodies in serum were present, however, some patients with chronic hepatitis C were positive for anti-HCV IgM too. The aim of this study was to assess the presence of anti-c22 IgM in patients with chronic hepatitis C and to determine whether the positivity for anti-c22 IgM has an impact on the histological finding in the liver. A total of 88 patients were examined (44 women, 44 men), mean age 48 years.

[A relapsing and protracted form of viral hepatitis A: comparison of adults and children].

In recent years in children and adults with acute viral hepatitis A relapses and a protracted course of the disease were described. The authors followed up 37 patients with viral hepatitis A (20 children and 17 adults) and compared the clinical course of the disease, the period of hospitalization, persistence of IgM anti-HAV antibody in serum, the incidence of relapses and protracted forms of the disease. In adults the mean hospitalization period was longer (28 days as compared with 19), the average serum bilirubin value was higher (94 mumol/l as compared with 51 mumol/l), there were more cases with obvious jaundice (59% as compared with 30%) and the early serum antibody IgM anti-HAV persisted longer (19 weeks as compared with 14 weeks).

Causes of acute exacerbations of chronic hepatitis B.

The authors analyzed acute exacerbations of chronic hepatitis B in 24 chronic HBsAg carriers (20 with positive HBeAg, 4 with anti-HBe), more than half of whom were treated with glucocorticoids, by examining specific antigens and antibodies of the hepatitis A virus (HAV), hepatitis B virus (HBV), hepatitis delta virus (HDV), Epstein-Barr virus (EBV) and cytomegalovirus (CMV). Of 38 observed exacerbations of the disease they found in 7 (18%) deterioration after discontinuation of glucocorticoids, in 7 (18%) seroconversion of HBeAg to anti-HBe, in 9 (24%) spontaneous exacerbation of chronic hepatitis B, in 11 (29%) chronic activation, reactivation of EBV superinfection, in 3 (8%) CMV reactivation or superinfection and in one (3%) HDV superinfection. In no instance HAV superinfection was observed.

[The first hyperimmune immunoglobulin against cytomegaloviruses made in the Czech Republic].

The Czech immunoglobulin CMV was administered to 16 subjects with active CMV infection--mostly women with repeated miscarriages, CMV primoinfection during pregnancy, to children with congenital CMV infection and to patients with other clinical forms. The immunoglobulin was administered in a single dose or repeatedly by the intramuscular route. The decline of activity of the CMV infection was demonstrated by a decline of specific IgM CMV antibodies, disappearance of previously assessed viriuria and isolation of CMV in smears from the uterine cervix.

Feeding of Dermacentor reticulatus (Fabr.) females depending on their age, origins and biotope of survival.

In Dermacentor reticulatus (Fabr., 1794) females originating from Slovakia and Poland the duration of feeding on host and its successful outcome depending on the age, origins of ticks and biotope of their survival was studied. In specimens older than a half year no influence of these factors on the duration of feeding was demonstrated.

Development of the tick Ixodes laguri Ol. in the nests of the European suslik Citellus citellus (L.).

In field and laboratory conditions new data were obtained concerning the life cycle of the nidicolous tick Ixodes laguri. The development of this tick was studied in experimental nests of the European suslik and a two-year cycle of I. laguri was demonstrated.

A comparison of developmental dynamics of Dermacentor reticulatus (Fabr.) of different geographic origins and their affection by different microclimate.

Developmental dynamics of D. reticulatus ticks of different geographic origins (NE Poland and SW Slovakia) were investigated and compared. A long-term field experiment was conducted in South Moravia in the zone of thermophilic oak forest.

Influence of microclimate on the life cycle of the common tick Ixodes ricinus (L.) in an open area in comparison with forest habitats.

Under conditions of the South-Moravian region of Pannonian climate (Valtice near Breclav), the life cycle of the common tick Ixodes ricinus (L.) was studied and a continous recording of main elements of microclimate (temperature and humidity) was carried out in an open grassy area. Simultaneously the process of hibernation was studied in four soil layers (surface, depths of 10, 20 and 30 cm).

Development and survival of the tick Hyalomma dromedarii Koch under laboratory conditions.

Developmental cycle of the tick Hyalomma dromedarii as influenced by changes of temperature and humidity was studied under laboratory conditions. Feeding and metamorphosis of developmental stages were observed under standard laboratory conditions, the metamorphosis was traced at exposure to temperature of 28 degrees C, 80% RH to alternating diurnal climate 40 degrees C, 25% RH and 20 degrees C, 80% RH and alternating humidity of 40/100% and 60/100% RH at a constant temperature 30 degrees C.

Possibilities of persistence in new biotopes of ticks imported by birds.

Survival and development of 6 tick species (Hyalomma anatolicum, Rhipicephalus sanguineus, Haemaphysalis punctata, Dermacentor marginatus, D. reticulatus and Ixodes ricinus) were studied in 3 groups differing in the range of distribution with respect to the place of importation, as a model for the knowledge of their possible inclusion in the new local biocenosis during transportation by natural hosts.

Influence of microclimate on the life cycle of the common tick Ixodes ricinus (L.) in thermophilic oak forest.

Under conditions of the South Moravian thermophilic oak forest (Valtice near Breclav), the life cycle of the common tick Ixodes ricinus was studied by continuous recording of main elements of microclimate (temperature and humidity) in three different biotopes: forest, margin of the forest and meadow. Simultaneously conditions and the process of tick hibernation were studied in four soil layers (surface, depths of 10, 20 and 30 cm). Observations made in the winter and vegetation periods were assessed by mathematical-statistical tests.