Instructive even after a decade: Complete results of initial virological diagnostics and re-evaluation of molecular data in the German rabies virus “outbreak” caused by transplantations
Introduction
During the past six decades, the clinical science of transplantation was one of the most fascinating and rapidly growing fields of medicine (Barker and Markmann, 2013). Generally, the benefits of transplantation for the patients in terms of an improved quality of life and an extension of life expectancy by far outweigh the undeniable risks to which transplant recipients are exposed. In this respect, viral infections are of particular concern, and there is a constant fear that certain “exotic” pathogens (Kaul, 2013, Waggoner et al., 2013), among them the West Nile virus (Iwamoto et al., 2003), the lymphocytic choriomeningitis virus (Fischer et al., 2006), and also the rabies virus, might be transferred to the recipients. The latter virus is mainly transmitted to humans by bites of infected animals in countries where the disease is enzootic and causes an almost uniformly fatal encephalitis (Bleck and Rupprecht, 2009, Hemachudha et al., 2013, Jackson, 2009, Mani and Madhusudana, 2013, Warrell and Warrell, 2004). Since the first successful kidney transplantation up to 2004 no more than eight incidents of human-to-human transmission of the rabies virus were recorded worldwide, and all these cases occurred among recipients of cornea grafts (Galian et al., 1980, Gode and Bhide, 1988, Houff et al., 1979, Javadi et al., 1996, Thongcharoen et al., 1981). In 2004 for the first time, four incidents of rabies infection in transplant patients could be ascribed to solid organ and vascular tissue grafting in the United States (Burton et al., 2005, Srinivasan et al., 2005). About one year later, in February 2005, in Germany the suspicion arose that six individuals, who had received organs and the corneas from a common donor, could have also been infected with the rabies virus by the transplants (Ross et al., 2005). The clinical courses of the recipients were reported in detail elsewhere (Maier et al., 2010, Vetter et al., 2011). This communication aims for the first time to provide the complete spectrum of virological findings initially raised in the two national reference laboratories for rabies virus infection and also includes the results of a re-evaluation of the primary molecular data.
Section snippets
Transplant recipients
In February 2005, symptoms of altered mental status were recorded in three recipients of the lung, the two kidneys, and the pancreas from a common organ donor (patients 1, 2, and 3 in Table 1). All patients developed rapid neurological deterioration and signs of an unexplained acute encephalitis between 40 and 43 days after the transplantations. Simultaneous rabies postexposure prophylaxis (WHO, 2013) was started immediately after the onset of symptoms. The patients died on days 49, 52, and 95
Samples
Specimens were sampled from the six transplant recipients at the clinical centres and were transported to the reference laboratories. Materials were aliquoted and stored at −80 °C in freezers which were connected to a central temperature monitoring system.
Detection of rabies virus antigen by fluorescent antibody testing (FAT)
Smears of brain tissues obtained at autopsies were tested for rabies virus antigen using the standard procedure described by Dean et al. (1996). Formalin-fixed samples from the organ donor's brain were subjected to a pre-treatment with
Findings in the organ donor
In a serum and in a portion of cerebrospinal fluid, which had been obtained both on 31 December 2004, no antibodies against the rabies virus could be detected. In smears of formalin fixed brain tissue rabies virus antigen was clearly visible, whereas rabies virus RNA from fixed brain tissue was only detectable in the course of re-evaluation of the primary molecular data by use of real-time PCR (data not shown).
Findings in transplant recipients suffering from encephalitis
The diagnostic findings obtained by different analyses from intra vitam samples of
Discussion
Infections with the rabies virus, which causes an almost uniformly fatal encephalitis in humans (Bleck and Rupprecht, 2009, Hemachudha et al., 2013, Jackson, 2009, Mani and Madhusudana, 2013, Warrell and Warrell, 2004), are generally rare in Europe. Between 1996 and 2004, in Germany, for instance, only two such cases were recorded (Malerczyk et al., 2011, Ross et al., 1997, Summer et al., 2004). Given the population of the country and the known average annual organ donation rate at that time,
Conclusions
Even a decade after its occurrence, the German “outbreak” of rabies virus infections caused by transplantations remains instructive from many points of view.
From a diagnostic angle, the complete data reported for the first time in this communication show that the concentrations of rabies virus RNA in saliva and skin, i.e. the two specimens which are most often used for intra vitam diagnosis, are 250–200,000 times lower than in the infected patient's brains. Furthermore, amounts of rabies virus
Acknowledgements
The authors are grateful to Mrs L. Gallina, Mrs J. Kliemt, Mrs K. Krause, Mrs A. Schameitat, and Mrs S. Tschammer for skilful technical assistance. They are also indebted to Mr A. Zibert, PhD (Münster University Hospital, University of Münster, Münster, Germany) for helpful discussion on the quantitative results obtained with real-time PCR and to Mrs Y. Rotivel, MD (Institute Pasteur, Paris, France) for providing additional information on the patient who received a cornea transplant from a
References (58)
- et al.
Molecular cloning and complete nucleotide sequence of the attenuated rabies virus SAD B19
Virology
(1990) - et al.
Screening of organ and tissue donors for rabies
Lancet
(2005) - et al.
Two rabies deaths after corneal grafts from one donor
Lancet
(1988) - et al.
Human rabies: neuropathogenesis, diagnosis, and management
Lancet Neurol.
(2013) - et al.
Ante mortem diagnosis of human rabies using saliva samples: comparison of real time and conventional RT-PCR techniques
J. Clin. Virol.
(2006) Antigenic variants of rabies virus
Comp. Immunol. Microbiol. Infect. Dis.
(1982)- et al.
Long-term humoral and cellular immunity after vaccination with cell culture rabies vaccines in man
Clin. Immunol. Immunopathol.
(1994) - et al.
Comparative detection of rabies RNA by NASBA, real-time PCR and conventional PCR
J. Virol. Methods
(2011) - et al.
Procedures for reproducible detection of rabies virus antigen mRNA and genome in situ in formalin-fixed tissues
J. Virol. Methods
(1997) - et al.
Rabies and other lyssavirus diseases
Lancet
(2004)