Ison, Michael G.

Abstract Background Cache Valley virus (CVV) is a mosquito-borne virus that is a rare cause of disease in humans. In the fall of 2020, a patient developed encephalitis 6 weeks following kidney transplantation and receipt of multiple blood transfusions. Methods After ruling out more common etiologies, metagenomic next-generation sequencing (mNGS) of cerebrospinal fluid (CSF) was performed. We reviewed the medical histories of the index kidney recipient, organ donor, and recipients of other organs from the same donor and conducted a blood traceback investigation to evaluate blood transfusion as a possible source of infection in the kidney recipient. We tested patient specimens using reverse-transcription polymerase chain reaction (RT-PCR), the plaque reduction neutralization test, cell culture, and whole-genome sequencing. Results CVV was detected in CSF from the index patient by mNGS, and this result was confirmed by RT-PCR, viral culture, and additional whole-genome sequencing. The organ donor and other organ recipients had no evidence of infection with CVV by molecular or serologic testing. Neutralizing antibodies against CVV were detected in serum from a donor of red blood cells received by the index patient immediately prior to transplant. CVV neutralizing antibodies were also detected in serum from a patient who received the co-component plasma from the same blood donation. Conclusions Our investigation demonstrates probable CVV transmission through blood transfusion. Clinicians should consider arboviral infections in unexplained meningoencephalitis after blood transfusion or organ transplantation. The use of mNGS might facilitate detection of rare, unexpected infections, particularly in immunocompromised patients.

Influenza is an important cause of hospitalization due to lower respiratory tract involvement for which there is no specific antiviral treatment with proven efficacy. We conducted a double-blind, randomized, placebo-controlled trial to assess the tolerability and efficacy of nebulized zanamivir (16 mg four times a day) in combination with rimantadine compared to rimantadine with nebulized saline for treating influenza in adults hospitalized with influenza. Twenty patients tolerated the inhaled zanamivir (ZNV) plus rimantadine without decline in peak expiratory flow rates compared to the 21 who received inhaled saline. The study was terminated early because the approval of ZNV made further enrolment untenable. No significant differences were observed in the proportion of patients shedding virus by treatment day 3 (57% ZNV plus rimantadine, 67% placebo plus rimantadine), or in the durations of hospitalization and supplemental oxygen use. More ZNV plus rimantadine recipients exhibited no or mild cough on day 3 of treatment (94 vs 55%, P=0.01). Two rimantadine-resistant viruses emerged during rimantadine monotherapy; no ZNV resistance was observed. Nebulized ZNV appears to be well tolerated in this hospitalized population but further studies are needed to assess its efficacy.

AbstractBackgroundBefore the 2014 policy change pertaining to infectious disease screening, many organ procurement organizations (OPOs) were supplementing serologic screening of deceased organ donors with nucleic acid testing (NAT) for human immunodeficiency virus (HIV‐1), hepatitis B virus (HBV), and hepatitis C virus (HCV). The number of seronegative,NAT‐positive donors has not been directly measured.MethodsHIV,HBV, andHCVscreening results of 11 229 donor referrals evaluated from 2010 to 2013 were obtained from 3OPO‐affiliated laboratories, capturing 35% of all donors in the United States. Laboratories used either polymerase chain reaction assay or transcription‐mediated amplification assay to test 9643 deceased donors byNAT.ResultsTheNATresults were positive in 21 (0.2%), 1 (0.02%), and 11 (0.1%) donors who were seronegative forHIV,HBV, andHCV, respectively. All discordantHIV‐1 results were from one laboratory using a polymrease chain reaction assay. Thirteen of the reactiveHIV NATresults in seronegative referrals were repeated and were non‐reproducibly positive (NRP). Ten (0.1%), 452 (7.8%), and 197 (2.2%) ofHIV‐,HBV‐, andHCV‐seropositive donors, respectively, were negative byNAT.ConclusionsThis study highlights the importance of robust quality assurance to minimizeNRP NATresults.NATmay allow for increased utilization of organs fromHBV‐ andHCV‐seropositive,NAT‐negative donors.

AbstractBackgroundThe optimal treatment for respiratory syncytial virus (RSV) infection in adult immunocompromised patients is unknown. We assessed the management of RSV and other non‐influenza respiratory viruses in Midwestern transplant centers.MethodsA survey assessing strategies for RSV and other non‐influenza respiratory viral infections was sent to 13 centers.ResultsMultiplex polymerase chain reaction assay was used for diagnosis in 11/12 centers. Eight of 12 centers used inhaled ribavirin (RBV) in some patient populations. Barriers included cost, safety, lack of evidence, and inconvenience. Six of 12 used intravenous immunoglobulin (IVIG), mostly in combination with RBV. Inhaled RBV was used more than oral, and in the post‐stem cell transplant population, patients with lower respiratory tract infection (LRTI), graft‐versus‐host disease, and more recent transplantation were treated at higher rates. Ten centers had experience with lung transplant patients; all used either oral or inhaled RBV for LRTI, 6/10 treated upper respiratory tract infection (URTI). No center treated non‐lung solid organ transplant (SOT) recipients with URTI; 7/11 would use oral or inhaled RBV in the same group with LRTI. Patients with hematologic malignancy without hematopoietic stem cell transplantation were treated with RBV at a similar frequency to non‐lung SOT recipients. Three of 12 centers, in severe cases, treated parainfluenza and metapneumovirus, and 1/12 treated coronavirus.ConclusionsTreatment of RSV in immunocompromised patients varied greatly. While most centers treat LRTI, treatment of URTI was variable. No consensus was found regarding the use of oral versus inhaled RBV, or the use of IVIG. The presence of such heterogeneity demonstrates the need for further studies defining optimal treatment of RSV in immunocompromised hosts.

Disseminated infection with Ureaplasma species causes fatal hyperammonemia syndrome in lung transplant recipients, likely by disrupting ammonia metabolism.