Gauss et al. Journal of Medical Case Reports 2012, 6:334 http://www.jmedicalcasereports.com/content/6/1/334 Page 4 of 5 Figure 2 Rooted maximum likelihood phylogenetic consensus tree for ORF1 nucleotide sequences of selected hepatitis E virus isolates. The sequence of the presented case (V11-17691, bold) clusters in genotype 3 is shown. The selected sequences represent nearest homologs in GenBank and typical members of genotype 1, 2, and 4 [6]. An avian hepatitis E virus sequence was used as an outgroup. Numbers at the nodes indicate bootstrap values of greater than 50%. Sequences are denoted by GenBank ID, country, International Organization for Standardization country code, source, and year of isolation (or publication). ch, chicken isolate; CN, China; CZ, Czech Republic; DE, Germany; ES, Spain; FR, France; hu, human; GR, Greece; Gt, genotype; JP, Japan; MM, Myanmar; MN, Mongolia; MX, Mexico; NL, The Netherlands; SE, Sweden; sw, swine; TD, Chad; US, United States. our case, rituximab therapy was stopped because of severe fatigue and increased susceptibility to infections. Conse- quently, our patient’s lymphocyte count in the blood increased from 0.8/nL at the time of referral to 9.4/nL at month 7. This may be interpreted as an indicator of a sim- ultaneous immune reconstitution and thus could explain the quick spontaneous clearance of the HEV infection and hepatitis between months 7 and 8. Notably, severe complications have also been observed in patients with HEV infection after liver transplant- ation. In a recently published case, undetected HEV in- fection in a liver transplant donor actually caused chronic HEV and cirrhosis in the recipient [15]. In addition to acute and chronic HEV infections in patients with hematological malignancies [3,5], patients with HIV have been reported with chronic HEV [4]. In our patient, antiviral treatment was not initiated, be- cause of the spontaneous recovery after immune reconsti- tution. However, beyond reduction of immunosuppressive therapy, treatment with ribavirin for at least 3 months seems to be the first treatment option for patients with chronic HEV, even though data are still limited [16]. Conclusions HEV is still regarded by many health-care professionals as a typical travel-associated disease. Consequently, HEV