Evaluation of the relationship between serum levels of VEGF and sVEGFR1 with mortality and prognosis in patients with Crimean-Congo hemorrhagic fever

Host response transcriptomic analysis of Crimean-Congo hemorrhagic fever pathogenesis in the cynomolgus macaque model

Crimean-Congo hemorrhagic fever virus (CCHFV) is a highly pathogenic tick-borne RNA virus prevalent in Asia, Europe, and Africa, and can cause a hemorrhagic disease (CCHF) in humans with mortality rates as high as 60%. A general lack of both effective medical countermeasures and a comprehensive understanding of disease pathogenesis is partly driven by an historical lack of viable CCHF animal models. Recently, a cynomolgous macaque model of CCHF disease was developed. Here, we document the targeted transcriptomic response of non-human primates (NHP) to two different CCHFV strains; Afghan09-2990 and Kosova Hoti that both yielded a mild CCHF disease state. We utilized a targeted gene panel to elucidate the transcriptomic changes occurring in NHP whole blood during CCHFV infection; a first for any primate species. We show numerous upregulated genes starting at 1 day post-challenge through 14 days post-challenge. Early gene changes fell predominantly in the interferon stimulated gene family with later gene changes coinciding with an adaptive immune response to the virus. There are subtle differences between viral strains, namely duration of the differentially expressed gene response and biological pathways enriched. After recovery, NHPs showed no lasting transcriptomic changes at the end of sample collection.

Association of MCP-1 promotor polymorphism with disease severity of Crimean-Congo hemorrhagic fever

Crimean-Congo hemorrhagic fever (CCHF) is a thick-borne viral zoonotic disease. The pathogenesis and the reasons why cases have a mild or severe course in CCHF have not yet been explained. In this study, we investigated the relationship between promoter -2518 A/G single-nucleotide polymorphism (SNP) of the MCP-1 gene and the clinical course of CCHF. The MCP-1-2518 A/G SNP (rs1024611) frequency was examined in 128 virologically/serologically confirmed CCHF patients and 181 healthy controls by using the PCR-RFLP method. When CCHF patients and controls were compared, no significant difference was found between genotype distributions and allele frequencies of the -2518 A/G SNP of MCP-1 gene (P > .05). Compared to the AA genotype, both AG (P = .016; OR = 2.57) and GG genotype (P = .039; OR = 3.43) were found with significantly higher frequencies in mild/moderate cases than in severe cases. Compared to the AG + GG genotype, AA showed a significant risk for severe CCHF (60.0% vs 38.4%, P = .02; OR = 2.41). In contrast, the AG genotype showed a significant protective effect against severe disease compared to AA + GG genotype (29.1% vs 47.9%, P = .013; OR = 2.58). Compared to mild/moderate cases, the A allele was found to be significantly higher in severe cases (0.745 vs 0.623, P = .039; OR = 1.77). However, no significant relationship was found between fatal and nonfatal cases in terms of genotype or allele frequencies (P > .05). In conclusion, both -2518 AA genotype and A allele of MCP-1 were associated with disease severity, and the AG genotype had a protective effect against a severe disease course in CCHF patients.

Prognostic factors, pathophysiology and novel biomarkers in Crimean-Congo hemorrhagic fever

Crimean-Congo hemorrhagic fever (CCHF) is a geographically widespread tick-borne zoonosis. The clinical spectrum of the illness varies from mild infection to severe disease and death. In severe cases, hemorrhagic manifestations develop, with fatality rates of 4-20%, depending on the geographic region and quality of the health care. Although vast majority of the CCHF cases were reported from Turkey, mortality rate is lower than the other regions, which is 5% on average. Prediction of the clinical course of the disease enables appropriate management planning by the physician and prompt transportation, if needed, of the patient to a tertiary care hospital for an intensive therapy. Thus, predicting the outcome of the disease may avert potential mortality. There are numerous studies investigating the prognostic factors of CCHF in the literature. Majority of them were reported from Turkey and included investigations on clinical and biochemical parameters, severity scoring systems and some novel biomarkers. Somnolence, bleeding, thrombocytopenia, elevated liver enzymes and prolonged bleeding times are the most frequently reported prognostic factors to predict the clinical course of the disease earlier. High viral load seems to be the strongest predictor to make a clinical decision about the patient outcome. The severity scoring systems based on clinically important mortality-related parameters are especially useful for clinicians working in the field to predict the course of the disease and to decide which patient should be referred to a tertiary care hospital for intensive care. In the light of the pathophysiological characteristics of CCHF, some new biomarkers of prognosis including cytokines, soluble adhesion molecules, genetic polymorphisms and coagulopathy parameters were also investigated. However most of these tests are not available to clinicians and they were obtained mostly for research purposes. In spite of the various studies about prognostic factors, they have several inherent limitations, including large variability in the results and confusing data that are not useful for clinicians in routine practice. In this paper, the results of diverse studies of the prediction of the prognosis in CCHF based on epidemiological, clinical and laboratory findings of the disease were summarized and suggestions for future studies are provided.

Relationship between IFNA1, IFNA5, IFNA10, and IFNA17 gene polymorphisms and Crimean-Congo hemorrhagic fever prognosis in a Turkish population range

Crimean-Congo hemorrhagic fever (CCHF) is a fatal emerging acute viral infection. Not much is known regarding the pathogenic mechanisms and the reasons behind severe or mild disease courses in CCHF. IFN-alpha (IFNA) is one of the essential cytokines in the immune system. Existence of single nucleotide gene polymorphisms (SNPs) in cytokines can cause susceptibility or resistance to viral agents and different clinical courses. Hence, the relationship between SNPs in genes encoding cytokines (IFNA1 -1823G/A (rs1332190), IFNA5 -2529T/A (rs758236), IFNA10 Cys20stop (rs10119910), and IFNA17 Ile184Arg (rs9298814) SNPs and disease susceptibility were investigated. The associations between SNPs and CCHF prognosis were also studied. Total 150 patients with CCHF and 170 healthy individuals were enrolled. Genotyping was performed by PCR-RFLP methods. The frequency of IFNA1 -1823 (rs1332190) GG genotype was significantly higher in control subjects than CCHF patients (20% vs. 8%; P = 0.01). For IFNA17 Ile184Arg (rs9298814) polymorphism, CCHF patients having TG genotype had a higher frequency than the control subjects (38% vs. 32.4%; P = 0.039). The distribution of TT + TG genotype frequencies was also significantly higher in CCHF group than the controls (97.3% vs. 91.8%; P = 0.049). Genotype and allele frequencies for IFNA subtypes between fatal and survivors were the same (P > 0.05). Genotype and allele frequencies between severe and mild/moderate CCHF patients were also the same (P > 0.05). The results show that IFNA1 rs1332190 and IFNA17 rs9298814 SNPs may play an important role in CCHF susceptibility. Determining the existence of other connections for IFNA SNPs and CCHF severity and fatality requires further investigations.

Health care response to CCHF in US soldier and nosocomial transmission to health care providers, Germany, 2009

Early recognition and implementation of appropriate infection control measures were effective in preventing further transmission.

In 2009, a lethal case of Crimean–Congo hemorrhagic fever (CCHF), acquired by a US soldier in Afghanistan, was treated at a medical center in Germany and resulted in nosocomial transmission to 2 health care providers (HCPs). After his arrival at the medical center (day 6 of illness) by aeromedical evacuation, the patient required repetitive bronchoscopies to control severe pulmonary hemorrhage and renal and hepatic dialysis for hepatorenal failure. After showing clinical improvement, the patient died suddenly on day 11 of illness from cerebellar tonsil herniation caused by cerebral/cerebellar edema. The 2 infected HCPs were among 16 HCPs who received ribavirin postexposure prophylaxis. The infected HCPs had mild or no CCHF symptoms. Transmission may have occurred during bag-valve-mask ventilation, breaches in personal protective equipment during resuscitations, or bronchoscopies generating infectious aerosols. This case highlights the critical care and infection control challenges presented by severe CCHF cases, including the need for experience with ribavirin treatment and postexposure prophylaxis.

Important of Angiopoietic System in Evaluation of Endothelial Damage in Children with Crimean-Congo Hemorrhagic Fever

BACKGROUND

Crimean-Congo hemorrhagic fever (CCHF) causes endothelial activation and dysfunction by affecting the endothelium directly or indirectly. In maintaining the vascular integrity, vascular endothelial growth factor (VEGF-A) and its receptor (VEGFR1) and angiopoietin-2 (Ang-2) and its receptor (Tie-2) are very important mediators. For this reason, we aimed at studying the association of Ang-2 and VEGF and their receptors Tie-2 and VEGFR1 with CCHF infection.

METHODS

Thirty one CCHF patients and 31 healthy controls (HC) were included in the study. CCHF patients were classified into 2 groups in terms of disease severity (severe and nonsevere). VEGF-A, VEGFR1, Ang-2 and Tie-2 levels were measured in all groups.

RESULT

Serum levels of Tie-2, Ang-2, VEGF-A and VEGFR1 were significantly increased in CCHF patients compared with the HC. Furthermore, serum Tie-2, Ang-2, VEGF and VEGFR1 levels were found to be significantly higher in the severe group than in the nonsevere and HC groups (P < 0.05 and P < 0.001, respectively). Also, Tie-2, Ang-2, VEGF-A and VEGFR1 levels were significantly higher in the nonsevere group than in the HC group (P < 0.05).

CONCLUSION

Having statistically significant higher Ang-2, Tie-2, VEGF-A and VEGFR1 levels in the severe group when compared with the other groups suggested that VEGF-related Ang-2/Tie-2 system played a critical role in the pathogenesis of the disease, and these markers could be used as the severity criteria.

Cytokines as biomarkers of Crimean-Congo hemorrhagic fever

Crimean-Congo hemorrhagic fever (CCHF) is a potentially severe disease caused by CCHF virus. As in other viral hemorrhagic fevers, it is considered that the course and outcome of the disease depend on the viral load and the balance among the immune response mediators, and that a fatal outcome is the result of a "cytokine storm." The level of 27 cytokines was measured in serum samples taken from 29 patients during the acute phase of the disease. Two cases were fatal. Among survivors, significant differences between severe and non-severe cases were observed in the levels of IP-10, and MCP-1, while the levels of IL-1b, IL-5, IL-6, IL-8, IL-9, IL-10, IL-15, IP-10, MCP-1, TNF-α, and RANTES differed significantly between fatal and non-fatal cases (P < 0.05). RANTES was negatively correlated with the outcome of the disease. A striking similarity with the cytokine patterns seen in Ebola virus disease was observed. A weak Th1 immune response was seen. The viral load was positively correlated with IL-10, IP-10, and MCP-1 levels, and negatively correlated with the ratio IL-12/IL-10. Especially IP-10 and MCP-1 were significantly associated with the viral load, the severity and outcome of the disease, and they could act as biomarkers and, probably, as potential targets for treatment strategies design.