Crimean-Congo Hemorrhagic Fever Case Series: a Chronology of Biochemical and Hematological Parameters

Introduction Crimean-Congo hemorrhagic fever (CCHF) is a widespread tick-borne zoonotic disease. Sporadic outbreaks of CCHF occur in endemic regions, including Pakistan. The clinical spectrum of the illness varies from asymptomatic seroconversion to severe disease which may end in death. The treatment is supportive, including blood and blood products. There is multi-organ involvement in CCHF including acute hepatitis, thrombocytopenia, coagulopathy, acute kidney injury (AKI), and encephalopathy. Hematological and biochemical parameters may identify patients at substantial risk of worse outcomes. Early detection of the disease and forecasting the clinical course may be helpful. This case series aims to evaluate the trends of hematological and biochemical parameters among the survivors and non-survivors of CCHF. Methods All consecutive patients aged 16 years and above admitted to the isolation unit of Hayatabad Medical Complex, Peshawar, Pakistan between 1^st July and 30^th July 2022 with the diagnosis of CCHF were included in this case series. The diagnosis of CCHF was made by detecting viral ribonucleic acid by a polymerase chain reaction. For all patients, age, gender, address, occupation, clinical presentation, history of contact with animals, and travel history were recorded. All the vitals were taken regularly. The hematological (complete blood count) and biochemical parameters (serum creatinine, alanine aminotransferase (ALT), and C-reactive protein (CRP)) were documented daily. The blood group was determined for all the cases. Results Out of 17 cases, the majority (16 cases, 94.1%) were male and butchers (eight cases, 47.1%) by profession. All cases had significant contact with animals. Four patients (23.5%) died. Three out of the four non-survivors (75%) had ALT < 5 times the upper limit of normal with a static pattern of liver enzymes without much decline in ALT till death. One non-survivor (25%) had marked elevation of ALT at presentation, which had a declining trend till death. Seven out of 13 survivors (53.8%) had moderate to marked elevation in the level of ALT at presentation. The ALT showed a downward trend during the course of illness in all these patients. The remaining survivors (six out of 13, 46.2%) had a mild elevation of ALT and 50% of them showed improvement in the ALT level during hospitalization. All patients had thrombocytopenia at presentation. None of the non-survivors showed a persistent increase in the platelet count, and three cases remained severely thrombocytopenic at the time of death. However, the trend in platelet count among all the survivors was increasing. The CRP level in the majority (three out of four cases, 75%) of the non-survivors remained elevated till death, while all survivors showed a progressive decline in CRP level. A majority (11 out of 17 cases) had blood group B. Half of the non-survivors (two out of four cases) and the majority of the survivors (nine out of 13 cases) had blood group B. AKI was found in all non-survivors, while all the survivors had normal renal function throughout the course. Conclusion A persistently raised ALT and CRP level, a persistently low or decreasing platelet count, and AKI were associated with mortality. Blood group B was the commonest blood group among patients of CCHF, which is not reflective of the blood group distribution of the general population from which this case series has been reported.