Clinical and laboratory findings in patients with oliguric and non-oliguric Hantavirus haemorrhagic fever with renal syndrome: an analysis of 128 patients

Patients with haemorrhagic fever with renal syndrome (HFRS) may present without significant oliguria. We compared different initial clinical symptoms and laboratory findings in patients who developed oliguric acute renal failure (ARF) with those in patients who did not develop oliguric ARF. Overall, 128 patients with serologically confirmed HFRS were hospitalized at the University Hospital for Infectious Disease, Zagreb, Croatia between January 1999 and December 2010. Clinical signs and laboratory findings were extracted from medical charts, and were assessed for their relationship to the development of oliguric ARF. Puumala virus infection was diagnosed in 101 (79%) patients, and Dobrava-Belgrade virus infection in 27 (21%). Oliguria or anuria developed in 30% of patients. We identified the following risk factors for the development of oliguria and anuria on multivariable analysis: conjunctival hyperaemia or bleeding (relative risk (RR) 1.84, 95% CI 1.09–3.10; p 0.023), diarrhoea (RR 1.45, 95% CI 1.07–1.97; p 0.017), serum sodium of ≤133 mM (RR 2.21, 95% CI 1.34–3.64; p 0.002), and dipstick protein value of >1.5 g/L (RR 1.59, 95% CI 1.09–2.33; p 0.016), as well as hiking in the forest (RR 1.92, 95% CI 1.13–3.26; p 0.016). Our findings may help physicians in the earlier identification of patients with a more severe form of HFRS caused by Puumala and Dobrava-Belgrade viruses. Particular attention should be given to findings such as conjunctival hyperaemia or bleeding, diarrhoea, a low serum sodium level, and proteinuria.