Characterisation of inflammatory response, coagulation, and radiological findings in Katayama fever: a report of three cases at the Medical University of Vienna, Austria

BACKGROUND: Katayama fever is an acute clinical condition characterised by high fever, dry cough and general malaise occurring during early Schistosoma spp. infection. It is predominantly reported in travellers from non-endemic regions. Whereas the immunological response to Schistosoma infection is well characterised, alterations in inflammatory markers and coagulation in response to acute infection are poorly understood. METHODS: Here we report the clinical, laboratory and radiological characteristics of three returning travellers with Katayama fever. Inflammatory markers and coagulation status were assessed repeatedly during follow-up to characterise the host response to infection. Radiographic findings were correlated with clinical and laboratory markers. RESULTS: Clinical symptoms were suggestive of a significant inflammatory response in all patients including high fever (>39°C), cough, and general malaise. Classical inflammatory markers including blood sedimentation rate, C-reactive protein, and serum amyloid A were only moderately elevated. Marked eosinophilia (33–42% of white blood cells) was observed and persisted despite anti-inflammatory and anthelminthic treatment for up to 32 weeks. Analysis of blood coagulation markers indicated increased coagulability reflected by elevated D-dimer values (0.57–1.17 μg/ml) and high thrombin generating potentials (peak thrombin activity: 311–384 nM). One patient showed particularly high levels of microparticle-associated tissue factor activity at initial presentation (1.64 pg/ml). Multiple pulmonary and hepatic opacities demonstrated by computed tomography (CT) scanning were associated with raised inflammatory markers in one patient. CONCLUSIONS: The characterisation of the inflammatory response, blood coagulation parameters and radiological findings in three patients adds to our current understanding of Katayama fever and serves as a starting point for further systematic investigations of the pathophysiology of this acute helminthic infection.