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Background Many studies have shown that invasive pulmonary aspergillosis, cryptococcosis, and mucormycosis can mimic radiographic and clinical features of primary lung cancer. However, more research surveying the incidence and outcomes of these fungal infections among patients with a history of lung cancer is needed. The aim of this study was to describe the occurrence and clinical outcomes of opportunistic invasive fungal infections that can mimic tumors in non–small-cell lung cancer patients. Patients and Methods Patients seen at Stanford University Medical Center from January 1, 2007, to May 1, 2020, with pulmonary aspergillosis, cryptococcosis, or mucormycosis after non–small-cell lung cancer (NSCLC) diagnosis were reviewed. The European Organization for Research and Treatment of Cancer National Institute of Allergy and Infectious Diseases Mycoses Study Group criteria was used to classify patients with evidence of proven or probable invasive fungal infection within our cohort. Results A total of 12 patients with proven or probable invasive mold infection (including 8 cases of aspergillosis) and 1 patient with proven cryptococcosis were identified, without any cases of mucormycosis. Of this cohort, 6 patients (46%) showed radiographic findings that were found to be most consistent with lung cancer by radiologists. Eight cases (62%) were suspected of cancer recurrence or progression by the treatment team on the basis of additional considerations of medical history and clinical symptoms. Most patients had active NSCLC or had a history of recurrence without active NSCLC at the time of fungal discovery (11 patients; 85%). Most patients died without full recovery (7 patients; 54%). Conclusions Invasive pulmonary aspergillosis and cryptococcosis can often be mistaken as cancer recurrence or progression in patients with a history of NSCLC because of mimicking radiographic and clinical characteristics.

Histoplasmosis-associated hemophagocytic lymphohistiocytosis is a rate but lethal disease in immunocompromised hosts. Unusual clinical presentations make diagnosing invasive fungal infection even more challenging. Here we present a case of hemophagocytic lymphohistiocytosis secondary to progressive disseminated histoplasmosis presenting as cellulitis in a patient with systemic lupus erythematous. A high index of suspicion combined with histopathology and molecular diagnostic techniques are important to establish an accurate and timely diagnosis of opportunistic infections in immunocompromised patients.

Background Invasive fungal infection (IFI) is a growing cause of morbidity and mortality in oncology and transplant patients. Diagnosis of IFI is often delayed due to need for invasive biopsy and low sensitivity of conventional diagnostic methods. Fungal cell-free DNA (cfDNA) detection in plasma is a novel testing modality for the noninvasive diagnosis of IFI. Methods A novel bioinformatic pipeline was created to interrogate fungal genomes and identify multicopy sequences for cfDNA polymerase chain reaction (PCR) targeting. A real-time PCR panel was developed for 12 genera and species most commonly causing IFI. Sensitivity and specificity of the fungal PCR panel were determined using plasma samples from patients with IFI and non-IFI controls. Clinical impact of the fungal PCR panel was evaluated prospectively based on the treating team’s interpretation of the results. Results Overall, the sensitivity and specificity were 56.5% (65/115; 95% confidence interval [CI], 47.4–65.2) and 99.5% (2064/2075; 95% CI, 99.0–99.7), respectively. In the subset of patients with an optimized plasma volume (2 mL), sensitivity was 69.6% (48/69; 95% CI, 57.9–79.2). Sensitivity was 91.7% (11/12; 95% CI, 62.5–100) for detection of Mucorales agents, 56.3% (9/16; 95% CI, 33.2–76.9) for Aspergillus species, and 84.6% (11/13; 95% CI, 56.5–96.9) for Candida albicans. In a prospective evaluation of 226 patients with suspected IFI, cfDNA testing was positive in 47 (20.8%) patients and resulted in a positive impact on clinical management in 20 of 47 (42.6%). Conclusions The fungal cfDNA PCR panel offers a noninvasive approach to early diagnosis of IFI, providing actionable results for personalized care.

Invasive fungal diseases (IFDs) are common in patients with acute myeloid leukemia (AML), but no recent data on incidence without antifungal prophylaxis are available. We evaluated the incidence of IFDs in patients with AML undergoing induction chemotherapy at Stanford University Hospital from 2012 to 2017, for up to 12 weeks after induction. We also analyzed factors associated with IFD development. Thirty-six of 240 patients (13%) developed at least one proven or probable IFD. Seventy-eight percent of the proven or probable IFDs were due toiCandida/ioriAspergillus/ispecies. Infection due toiFusarium/iandiMucorales/iwas uncommon. Absolute neutrophil count (ANC) oflt;500 µL/L at the start of induction was associated with an increased risk of IFD. One hundred and eighty-seven patients (78%) were started on systemic antifungal drugs, even without microbiologic evidence of an IFD. IFDs remain frequent in AML patients undergoing induction chemotherapy without antifungal prophylaxis.

Herpesviruses such as herpes simplex virus (HSV) type 1 and 2, varicella-zoster virus (VZV), and cytomegalovirus (CMV) maintain lifelong latency in the host after primary infection and can reactivate periodically either as asymptomatic viral shedding or as clinical disease. Immunosuppression, including biologic therapy, may increase frequency and severity of herpesvirus reactivation and infection. Licensed biologics are reviewed regarding their risks of potentiating HSV, VZV, and CMV reactivation and infection. Approaches to prophylaxis against HSV, VZV, and CMV infection or reactivation are discussed.

Background Skull base osteomyelitis (SBO) is an infection of the central cranial bones, most commonly resulting from contiguous spread of infection from adjacent head and neck structures. SBO is a well‐recognized complication of treatment of head and neck cancer (HNC) that results in significant morbidity. Methods We conducted a retrospective chart review of HNC patients diagnosed with SBO. Results SBO was commonly diagnosed with nasal endoscopy showing mucosal breakdown between the naso/oropharynx and skull base and with characteristic changes on CT/MRI. Culture data were often polymicrobial, inclusive of naso/oropharyngeal flora, but half of the patients additionally had antibiotic‐resistant or atypical pathogens. The mean duration of antimicrobial therapy was 117 +/− 94 days. Recurrent SBO was found in half of the patients, associated with Pseudomonas aeruginosa and with persistent defects in the mucosa abutting the skull base. Conclusions Diagnosis and management of SBO in HNC patients are challenging. Recommendations to aid in clinical care are proposed. Level of evidence 4, case series.

Cytomegalovirus (CMV) reactivation is common in organ transplant recipients and can lead to significant morbidity and mortality. Cutaneous CMV findings are rarely reported in the literature and diagnosis can be delayed if not clinically recognized. We describe a case of a female patient 20 years post renal transplant who presented with extensive ulcerative skin lesions and diarrhea. She rapidly deteriorated and died on day 5 of hospitalization. Autopsy noted extensive CMV involvement of skin and gastrointestinal (GI) tract by CMV-specific immunohistochemistry. These findings, along with high-grade CMV viremia, led to the final postmortem diagnosis of disseminated CMV infection. This case focuses on the cutaneous findings of disseminated CMV as recognition of CMV skin lesions can lead to earlier initiation of appropriate therapy in transplant recipients.

Liver transplant recipients (LTRs) are at risk for vancomycin-resistant Enterococcus (VRE) infections which can lead to significant morbidity or mortality. Antibiotic exposure, including vancomycin, is associated with greater risk of VRE infection. This study aimed to assess the appropriateness of vancomycin use and rates of VRE infection in this population. We performed a retrospective cohort study of 327 patients who underwent liver transplantation at our center from January 1, 2012 to June 30, 2017. Sixty (18.3%) LTRs had at least one VRE-positive culture between six-months pre-transplant and six-months post-transplant. LTRs with VRE had greater vancomycin exposure as compared to VRE-negative LTRs (p < 0.05) and were more likely to receive prolonged vancomycin courses (> 72 hours, p < 0.05). Overall appropriateness of vancomycin use > 72 hours among VRE-positive LTRs was only 26.8%. Inappropriate vancomycin use most commonly occurred in patients with presumed sepsis without an identifiable source or pneumonia with negative respiratory cultures. Our findings illustrate an opportunity to improve antibiotic stewardship and reduce vancomycin use in the transplant population

Background Patients with lymphoproliferative disorders following hematopoietic stem cell transplant (HSCT) most commonly present with fever and lymphadenopathy within the first 5 months of transplant. Pulmonary post-transplant lymphoproliferative disorder (PTLD) is a particularly aggressive and rapidly progressive disease, with high morbidity and mortality. There are a very limited number of reported pulmonary PTLD cases following HSCT in patients with acute myeloid leukemia (AML). Early diagnosis and detection of pulmonary PTLD is critical given its high lethality. However, variable clinical presentations and nonspecific radiographic findings make pulmonary PTLD difficult to distinguish from other more common causes of pulmonary disease in AML patients. Case presentation Here, we describe a 68-year-old Caucasian man who presented for salvage induction therapy following relapse of his AML after a haploidentical allogeneic HSCT 10 months earlier. He developed recurrent fevers, dry cough, and hypoxemia, with chest computed tomography (CT) showing bibasilar consolidations and increased nodularity without increased lymphadenopathy. His symptoms initially improved with antibiotic and antifungal therapy, but his follow-up chest CT showed progression of disease despite symptomatic improvement. Epstein–Barr virus (EBV) was detected in his blood by polymerase chain reaction (PCR), and a lung biopsy revealed monomorphic PTLD with B cells positive for EBV. Unfortunately, the patient’s condition rapidly deteriorated, and he passed away prior to treatment initiation. Conclusions To our knowledge, this is the first reported case of an AML patient developing pulmonary PTLD relatively late in his post-transplant course in the setting of relapsed disease and salvage therapy. Pulmonary PTLD, a rare but highly lethal disorder, can imitate the symptoms and radiographic findings of pneumonia, a common diagnosis in immunocompromised AML patients. This case illustrates the importance of considering pulmonary PTLD in the differential diagnosis for pulmonary disease in AML patients with a history of HSCT, especially in the setting of progressive radiographic findings despite broad antibacterial and antifungal therapy. Further, our case demonstrates the importance of biopsy and uninterrupted EBV DNA monitoring in the definitive diagnosis of PTLD, given nonspecific symptomatology and radiographic findings.

Advances in solid organ transplantation have improved the survival of end-stage organ disease at the expense of an increased risk for opportunistic infections. Unusual clinical presentations and the possibility of concurrent infections make diagnosing invasive fungal infection (IFI) more difficult. Here, we present a case of simultaneous vertebral infection caused by Coccidioides immitis-posadasii and subcutaneous phaeohyphomycosis due to Nigrograna mackinnonii in a kidney transplant recipient. The diagnosis of both infections required invasive procedures to obtain tissue and a high index of suspicion that more than one IFI could be present. A multidisciplinary team approach for the management of immunocompromised patients with suspected or diagnosed IFI is warranted.

The risk of JC polyomavirus encephalopathy varies among biologic classes and among agents within the same class. Of currently used biologics, the highest risk is seen with natalizumab followed by rituximab. Multiple other agents have also been implicated. Drug-specific causality is difficult to establish because many patients receive multiple immunomodulatory medications concomitantly or sequentially, and have other immunocompromising factors related to their underlying disease. As use of biologic therapies continues to expand, further research is needed into pathogenesis, treatment, and prevention of JC polyomavirus encephalopathy such that risk for its development is better understood and mitigated, if not eliminated altogether.

Hematopoietic cell transplantation (HCT) is potentially curative for patients with hematologic disorders, but carries significant risks of infection-related morbidity and mortality. Infectious diseases are the second most common cause of death in HCT recipients, surpassed only by progression of underlying disease. Many infectious diseases are difficult to diagnose and treat, and may only be first identified by autopsy. However, autopsy rates are decreasing despite their value. The clinical and autopsy records of adult HCT recipients at our center who underwent autopsy between 1 January 2000 and 31 December 2017 were reviewed. Discrepancies between premortem clinical diagnoses and postmortem autopsy diagnoses were evaluated. Of 185 patients who underwent autopsy, 35 patients (18.8%) had a total of 41 missed infections. Five patients (2.7%) had >1 missed infection. Of the 41 missed infections, 18 (43.9%) were viral, 16 (39.0%) were fungal, 5 (12.2%) were bacterial, and 2 (4.9%) were parasitic. According to the Goldman criteria, 31 discrepancies (75.6%) were class I, 5 (12.2%) were class II, 1 (2.4%) was class III, and 4 (9.8%) were class IV. Autopsies of HCT recipients frequently identify clinically significant infectious diseases that were not suspected premortem. Had these infections been suspected, a change in management might have improved patient survival in many of these cases. Autopsy is underutilized and should be performed regularly to help improve infection-related morbidity and mortality. Illustrative cases are presented and the lessons learned from them are also discussed.

The Enteroviridae are single-stranded RNA viruses in the Picornaviridae family notable for their ability to cause a wide range of diseases, with more severe disease manifestations in the immunocompromised host. Humans are the reservoir for Enteroviridae, and person-to-person transmission occurs via the fecal-oral or respiratory route. Intact innate immune response including NK cells and macrophages plays an important role during the initial phase of infection followed by T- and B-cell adaptive immunity, which is central in effective viral clearance. Enteroviral infections peak in the summer and fall months. Poliovirus classically causes a paralytic poliomyelitis with weakness and paralysis. Other enteroviral diseases include upper respiratory infections, HFMD, herpangina, myositis, myocarditis, aseptic meningitis, encephalitis, as well as a flaccid paralysis similar to poliovirus infection. Patients with B-cell immune defects including agammaglobulinemia are susceptible to chronic enterovirus infections including chronic meningoencephalitis. Patients undergoing HSCT may develop potentially life-threatening gastroenteritis and viral pneumonitis. No antiviral therapy is currently available; IVIG therapy is suggested for patients with enteroviral myocarditis and encephalitis. A comprehensive review of enteroviral illness is presented in the transplant population.

West Nile virus (WNV) is an emerging pathogen endemic in Africa and Europe. Recent events demonstrate the speed with which a vector-borne disease like WNV can disseminate when introduced into a susceptible, pathogen-naive population, where competent reservoir and vectors are present. Since the arrival of WNV to the North American continent in 1999, it is estimated that 2–4 million people have been infected in the USA alone. It has special relevance to the immunocompromised host populations because of the possibility of WNV transmission through organ transplantation and the increased risk of neuroinvasive disease in immunocompromised patients. In this chapter a detailed discussion of WNV infection with a focus in transplant population is presented.

Respiratory viral infections (RVIs) are common among the general population; however, these often mild viral illnesses can lead to serious morbidity and mortality among recipients of hematopoietic stem cell and solid organ transplantation. The disease spectrum ranges from asymptomatic or mild infections to life-threatening lower respiratory tract infection or long-term airflow obstruction syndromes. Progression to lower respiratory tract infection or to respiratory failure is determined by the intrinsic virulence of the specific viral pathogen as well as various host factors, including the type of transplantation, status of the host’s immune dysfunction, the underlying disease, and other comorbidities. This chapter focuses on the epidemiology, clinical manifestations, diagnosis, and management of RVIs in this susceptible population and includes respiratory syncytial virus, parainfluenza virus, human metapneumovirus, influenza virus, human coronavirus, and human rhinovirus. The optimal management of these infections is limited by the overall paucity of available treatment, highlighting the need for new antiviral drug or immunotherapies.

Background While invasive fungal infections (IFIs) are common in patients with acute myeloid leukemia (AML) undergoing induction chemotherapy, little current data exist on the epidemiology of IFIs in this patient population given widespread use of antifungal prophylaxis. Because our institution does not administer antifungal prophylaxis, we are in a unique position to study the natural history of IFIs in these patients. Methods We evaluated the incidence of IFIs using established definitions in adults with AML undergoing induction chemotherapy at Stanford Health Care from 2012 to 2017. We also analyzed incidence of antifungal treatment, impact of IFI diagnosis on survival, and risk factors for IFI development. Patients were followed for up to 12 weeks after beginning induction chemotherapy. Results Of 488 patients analyzed, 243 were eligible for inclusion. The median age was 57 (interquartile range 45–65). Men composed 134 (55%) of the patients and 157 (65%) where white. Fifty-four (22%) had antecedent myelodysplastic syndrome; most received a “7 + 3” regimen involving cytarabine and an anthracycline. Thirty-one (13%) developed a proven or probable IFI; 104 (43%) developed a proven, probable, or possible IFI. Most IFIs were due to lower respiratory tract disease. Eighteen identified organisms were Candida, including six C. albicans. Eight organisms were mold, including four Aspergillus isolates (all but one A. fumigatus) and one isolate each of Fusarium solani, Rhizomucor, Rhizopus, and Scedosporium apiospermum/Pseudallescheria boydii. One hundred ninety patients (78%) received antifungals during their initial admission and 99 (46%) of patients surviving their initial admission were discharged on antifungals. Only 66.7% of patients with a proven or probable IFI survived through 12 weeks, compared with 92.2% of those without (P = 0.007). Baseline absolute neutrophil count ≤500 cells/μL and longer duration of neutropenia were significantly associated with development of proven or probable IFIs. Conclusion Among patients receiving induction chemotherapy for AML, IFIs due to Candida and mold remain frequent absent antifungal prophylaxis and are associated with worse survival. Our findings support the use of antifungal prophylaxis in this patient population. Disclosures All authors: No reported disclosures.

Infection with Scedosporium species is associated with a significant morbidity and mortality and is becoming increasingly common, especially in immunocompromised patients. We describe the presentation and successful management of an immunocompromised patient with Scedosporium apiospermum infection of the upper urinary tract system, a rare disease manifestation. The current literature on urinary tract scedosporiosis is further reviewed with emphasis on treatment options and limitations of current antifungal therapy.

Legionella micdadei is a potential cause of invasive lung infections in immunocompromised hosts. On biopsy specimens, it can appear as an acid-fast bacillus (AFB) and can be mistaken for a member of genus Mycobacterium. As Legionella requires selective media to grow in culture, and a commonly used, commercially available urine antigen test for Legionella only detects Legionella pneumophila serogroup 1 but not L. micdadei, it is important to consider this organism in the differential diagnosis for AFB in immunocompromised hosts. We report a case of Legionella micdadei infection, which was initially treated empirically for non-tuberculous mycobacteria based on acid fast staining of biopsy tissue before the final diagnosis was made.

Malaria results in over 650,000 deaths each year; thus, there is an urgent need for an effective vaccine. Pre-clinical studies and recently reported human trials suggest that pre-erythrocytic stage vaccines can provide protection against infection. A Phase 1, randomized, placebo-controlled, dose-escalation study was conducted with a vaccine composed of a replication-deficient adenovirus-35 backbone with P. falciparum circumsporozoite (CS) surface antigen (Ad35.CS.01). Healthy adult subjects received three doses of 10 (8), 10 (9), 10 (10), or 10 (11) vp/mL Ad35.CS.01 vaccine or saline placebo intramuscularly at 0, 1, and 6-mo intervals. Adverse events were assessed and anti-CS antibody responses were determined by ELISA. Seventy-two individuals were enrolled, with age, gender, and ethnicity similar across each study arm. While the vaccine was generally well tolerated, adverse events were more frequent in the highest dose groups (10 (10) and 10 (11) vp/mL). More robust humoral responses were also noted at the highest doses, with 73% developing a positive ELISA response after the three dose series of 10 (11) vp/mL. The Ad35.CS.01 vaccine was most immunogenic at the highest dosages (10 (10) and 10 (11) vp/mL). Reactogenicity findings were more common after the 10 (11) vp/mL dose, although most were mild or moderate in nature and resolved without therapy.

Objectives: To describe and discuss the utility and potential pitfalls of ribosomal RNA locus sequencing for direct identification of invasive fungi from fresh and formalin-fixed, paraffin-embedded specimens. Methods: DNA was extracted from fresh and formalin-fixed, paraffin-embedded tissue and subjected to real-time polymerase chain reaction (PCR) targeting ITS2 and D2 regions of fungal ribosomal RNA locus. Cycle sequencing was performed on PCR products, and the identity of sequences was determined using a public database. Results: Four clinical cases of invasive fungal infection are presented to illustrate the utility of DNA sequencing for determining etiology when microbiological culture is negative, for shortening the time to identification of slow-growing fungi, for guiding antifungal therapy, and for shedding light on the pathogenesis of disseminated fungal infection. Conclusions: Fungal ribosomal RNA locus sequencing from fresh or formalin-fixed, paraffin-embedded specimens is a powerful tool for rapid and accurate diagnosis of patients with culture-negative or uncultured invasive mycosis.

We present a case of donor-derived coccidioidomycosis in a cardiac transplant patient and review previous cases of donor-derived coccidioidomycosis in solid organ transplant. Donor-derived coccidioidomycosis is rare, can be difficult to diagnose and has significant mortality., Background. Endocarditis is a rare manifestation of infection with Coccidioides. This is the first reported case of donor-derived Coccidioides endocarditis obtained from a heart transplant. Methods. We present a unique case of donor-derived Coccidioides immitis endocarditis and disseminated infection in a heart transplant patient. We also conducted a review of the literature to identify other cases of donor-derived coccidioidomycosis in solid organ transplant recipients and reviewed their clinical characteristics. Results. Fifteen prior cases of donor-derived coccidioidomycosis were identified. A majority of these cases were diagnosed by positive culture (83%). Mortality was high at 58%. Conclusions. Clinicians should maintain a high index of suspicion for disseminated coccidioidomycosis in patients who received transplants with organs from donors with a history of residing in endemic regions.

Haematological patients with neutropenic fever are frequently evaluated with chest computed tomography (CT) to rule out invasive fungal infections (IFI). We retrospectively analysed data from 100 consecutive patients with neutropenic fever and abnormal chest CT from 1998 to 2005 to evaluate their chest CT findings and the yield of diagnostic approaches employed. For their initial CTs, 79% had nodular opacities, with 24.1% associated with the halo sign. Other common CT abnormalities included pleural effusions (48%), ground glass opacities (37%) and consolidation (31%). The CT findings led to a change in antifungal therapy in 54% of the patients. Fifty-six patients received diagnostic procedures, including 46 bronchoscopies, 25 lung biopsies and seven sinus biopsies, with a diagnostic yield for IFI of 12.8%, 35.0% and 83.3%, respectively. In conclusion, chest CT plays an important role in the evaluation of haematological patients with febrile neutropenia and often leads to a change in antimicrobial therapy. Pulmonary nodules are the most common radiological abnormality. Sinus or lung biopsies have a high-diagnostic yield for IFI as compared to bronchoscopy. Patients with IFI may not have sinus/chest symptoms, and thus, clinicians should have a low threshold for performing sinus/chest imaging, and if indicated and safe, a biopsy of the abnormal areas.

Background Hemophagocytic lymphohistiocytosis (HLH) is a rare hematologic disorder which is characterized by excessive immune activation. In adults, it is typically secondary to an underlying process such as autoimmune disease, infection, or malignancy. Guidelines based on expert opinion suggest prophylaxis (PPX) with antiviral, antibacterial, and/or antifungal agents for patients undergoing treatment for HLH; however, the incidence of infectious complications is not known. We aimed to study the scope of infection in patients with HLH to help determine the best strategy for antimicrobial PPX. Methods We performed a retrospective chart review of 56 adult patients who fulfilled clinical diagnostic criteria for HLH treated at Stanford University Hospital between 2012 and 2018. Infections diagnosed up to 1 month prior and up to 6 months after a diagnosis of HLH were reviewed. Results A total of 57 episodes of HLH in 56 patients were reviewed. Infection was determined to be the trigger of HLH in five cases (EBV in three cases, Histoplasma in one case, MAC or HHV6 in one case). Antiviral PPX was used in 72%, PCP PPX in 75%, and antifungal PPX in 77% of HLH episodes. At least one infectious complication occurred in 33 of 57 episodes of HLH (58%) with 69 total infections diagnosed after HLH diagnosis: 46 bacterial, 12 viral, and 11 fungal. Bacterial infections included bacteremia (43%), pneumonia (15%), skin and soft tissue (13%), intra-abdominal infection (11%), urinary tract infection (13%), and others (5%). Of the viral infections, CMV viremia was the most prevalent and occurred in four patients (7% of HLH episodes). Fungal infections occurred in 19% of HLH episodes and included four yeast and seven mold infections (five proven and two possible). Three of these cases were not receiving antifungal PPX prior to infection; the remaining eight were breakthrough infections. Conclusion Infectious complications of HLH are common, and likely result from a combination of host immune factors related to underlying disease and induced by immunosuppressive chemotherapy. Most noteworthy is the incidence of fungal infections which supports the use of antifungal PPX in this patient population. Even with this, breakthrough infection, including with opportunistic molds, is not uncommon. Disclosures All authors: No reported disclosures.

Background Hematopoietic cell transplantation (HCT) is a potentially curative treatment option for patients with hematologic malignancies and other diseases but carries a significant risk of infection-related morbidity and mortality. Many of these infections are difficult to diagnose and treat. It is not infrequent that HCT recipients die from infection despite extensive investigations and broad-spectrum antimicrobial therapy. Autopsy is the gold standard for establishing the cause of death but rates of performing autopsies are decreasing despite their immense value. We present the most recent case series of infectious diseases found on autopsy in HCT recipients at our high-volume academic transplant center. Methods We retrospectively reviewed the medical charts and autopsy records of 131 HCT recipients who underwent autopsy between January 1, 2000 and December 31, 2016. The premortem clinical diagnoses as documented by the clinical teams were compared with autopsy findings. Discrepancies were identified and classified according to the Goldman Criteria (NEJM 1983; 308:1000–5). Results A total of 4,072 patients received 4,395 transplants between January 1, 2000 and December 31, 2016. Of the 1,937 patients who died, 131 (7%) had an autopsy performed. Of these 131 patients, 24 (18%) patients had a total of 29 infections that were identified only postmortem; 4 (3%) patients had >1 such infection. Of these 29 infections, 15 (52%) were viral, 9 (31%) were fungal, 3 (10%) were bacterial, and 2 (7%) were parasitic; no mycobacterial infections were found. According to the Goldman Criteria, 22 (76%) had class I discrepancies (“major diagnoses for which detection before death would in all probability have led to a change in management that might have resulted in cure or prolonged survival”). Illustrative cases of each infection type will be presented to highlight the challenges of infection management in HCT. Conclusion Autopsies of HCT recipients frequently identify clinically significant infections which were not suspected pre-mortem. Our study reinforces the educational value of the autopsy, which is underutilized but can be employed to help prevent future similar infectious complications and improve patient outcomes. Disclosures All authors: No reported disclosures.

Dosage-sparing strategies, adjuvants and alternative substrates for vaccine production are being explored for influenza vaccine development. We assessed the safety and immunogenicity of a Vero cell culture-grown inactivated whole virus influenza A/H5N1 vaccine with or without aluminum hydroxide adjuvant [Al(OH)(3)] in healthy young adults. Vaccines were well tolerated, but injection site discomfort was more frequent in groups receiving Al(OH)(3). Dose-related increases in serum antibody levels were observed. Neutralizing antibody titers varied significantly when tested by two different laboratories. Al(OH)(3) did not enhance HAI or neutralizing antibody responses, and contributed to increased injection site pain. Because influenza antibody titers vary significantly between different laboratories, international standardization of assays is warranted.

To augment the available influenza vaccine supply, a phase III study was conducted to evaluate the immunogenicity, safety, and consistency of a new trivalent inactivated influenza vaccine manufactured by CSL Limited. Healthy adults (ages 18-64) were randomized to receive either a single dose of TIV from multi-dose vials with thimerosal, TIV from pre-filled syringes without thimerosal, or placebo. Of the TIV recipients, 97.8% achieved a post-vaccination titer > or =40 against H1N1, 99.9% against H3N2 component, and 94.2% against influenza B. Few local or systemic adverse events were noted after vaccination with either TIV presentation. TIV was well tolerated and immunogenic.

Disseminated Fusarium infection can cause significant morbidity and mortality in immunocompromised patients. We present a case of disseminated fusariosis in a patient with neutropenic fever successfully treated using both liposomal amphotericin B and voriconazole. Combination anti-fungal therapy may be considered for such patients, particularly for those failing single-drug therapy.

Necrotic insults such as seizure are excitotoxic. Logically, membrane hyperpolarization by increasing outwardly conducting potassium channel currents should attenuate hyperexcitation and enhance neuron survival. Therefore, we overexpressed a small-conductance calcium-activated (SK2) or voltage-gated (Kv1.1) channel via viral vectors in cultured hippocampal neurons. We found that SK2 or Kv1.1 protected not only against kainate or glutamate excitotoxicity but also increased survival after sodium cyanide or staurosporine. In vivo overexpression of either channel in dentate gyrus reduced kainate-induced CA3 lesions. In hippocampal slices, the kainate-induced increase in granule cell excitability was reduced by overexpression of either channel, suggesting that these channels exert their protective effects during hyperexcitation. It is also important to understand any functional disturbances created by transgene overexpression alone. In the absence of insult, overexpression of Kv1.1, but not SK2, reduced baseline excitability in dentate gyrus granule cells. Furthermore, while no behavioral disturbances during spatial acquisition in the Morris water maze were observed with overexpression of either channel, animals overexpressing SK2, but not Kv1.1, exhibited a memory deficit post-training. This difference raises the possibility that the means by which these channel subtypes protect may differ. With further development, potassium channel vectors may be an effective pre-emptive strategy against necrotic insults.

Recently, preinduction of the heat shock response has been shown to protect CNS neurons undergoing various stressful insults, e.g., heat, ischemia, or exposure to excitotoxins. However, it is not known which of the proteins induced by the heat shock response mediate the protective effects. Previous correlative evidence points to a role for the highly stress-induced 72-kDa heat shock protein (hsp72). However, it is not known whether hsp72 expression alone can protect against a range of acute neuronal insults. We constructed a herpes simplex virus-1 vector carrying the rat brain stress-inducible hsp72 gene and the Escherichia coli lacZ (marker) gene. Infection with the vector caused hippocampal neurons to coexpress hsp72 and beta-galactosidase. Infection with a control vector led to marker gene expression only. Overexpression of hsp72 protected cultured hippocampal neurons against a heat shock but not against the metabolic toxin 3-nitropropionic acid or the excitotoxin glutamate. This is the first published report of protection following heat shock protein transfection in CNS neurons.

Increases in cytoplasmic Ca2+ concentration ([Ca2+]i) can lead to neuron death. Preventing a rise in [Ca2+]i by removing Ca2+ from the extracellular space or by adding Ca2+ chelators to the cytosol of target cells ameliorates the neurotoxicity associated with [Ca2+]i increases. Another potential route of decreasing the neurotoxic impact of Ca2+ is to overexpress one of the large number of constitutive calcium-binding proteins. Previous studies in this laboratory demonstrated that overexpression of the gene for the calcium-binding protein calbindin D28K, via herpes simplex virus (HSV) amplicon vector, increases the survival of hippocampal neurons in vitro following energetic or excitotoxic insults but not following application of sodium cyanide. We now report that in vivo hippocampal infection with the calbindin D28K HSV vector increases neuronal survival in the dentate gyrus after application of the antimetabolite 3-acetylpyridine and increases transsynaptic neuronal survival in area CA3 following kainic acid neurotoxicity. The protective effects of infection with the calbindin D28K vector in an intact brain may prove to be beneficial during changes in Ca2+ homeostasis caused by neurological trauma associated with aging and certain neurological diseases.

Gene transfer into neurons via viral vectors for protection against acute necrotic insults has generated considerable interest. Most studies have used constitutive vector systems, limiting the ability to control transgene expression in a dose-dependent, time-dependent, or reversible manner. We have constructed defective herpes simplex virus vectors designed to be induced by necrotic neurological insults themselves. Such vectors contain a synthetic glucocorticoid-responsive promoter, taking advantage of the almost uniquely high levels of glucocorticoids—adrenal stress steroids—secreted in response to such insults. We observed dose-responsive and steroid-specific induction by endogenous and synthetic glucocorticoids in hippocampal cultures. Induction was likely to be rapid enough to allow transgenic manipulation of relatively early steps in the cascade of necrotic neuron death. The protective potential of such a vector was tested by inclusion of a neuroprotective transgene (the Glut-1 glucose transporter). Induction of this vector by glucocorticoids decreased glutamatergic excitotoxicity in culture. Finally, both exogenous glucocorticoids and excitotoxic seizures induced reporter gene expression driven from a glucocorticoid-responsive herpes simplex virus vector in the hippocampus in vivo .

Brain areas damaged by stroke and seizures express high levels of the 72-kd heat shock protein (HSP72). Whether HSP72 represents merely a marker of stress or plays a role in improving neuron survival in these cases has been debated. Some induced tolerance experiments have provided correlative evidence for a neuroprotective effect, and others have documented neuroprotection in the absence of HSP72 synthesis. We report that gene transfer therapy with defective herpes simplex virus vectors overexpressing hsp72 improves neuron survival against focal cerebral ischemia and systemic kainic acid administration. HSP72 overexpression improved striatal neuron survival from 62.3 to 95.4% in rats subjected to 1 hour of middle cerebral artery occlusion, and improved survival of hippocampal dentate gyrus neurons after systemic kainic acid administration, from 21.9 to 64.4%. We conclude that HSP72 may participate in processes that enhance neuron survival during transient focal cerebral ischemia and excitotoxin-induced seizures.

Considerable interest has focused on the possibility of using viral vectors to deliver genes to the central nervous system for the purpose of decreasing necrotic neuronal injury. To that end, we have previously shown that a herpes simplex virus (HSV) vector expressing Bcl-2 could protect neurons from ischemia. In that study, vector was delivered before the ischemia. However, for such gene therapy to be of clinical use, vectors must be protective even if delivered after the onset of the insult. In the present study, we show that an HSV vector expressing Bcl-2 protects striatal neurons when delivered after focal ischemia. Rats were exposed to middle cerebral artery occlusion for 1 hour, followed by reperfusion, and damage was assessed 48 hours later. Delivery of the Bcl-2 vector 30 minutes after reperfusion (i.e., 1.5 hours after ischemia onset) prevented any significant loss of virally-targeted neurons in the striatum. In contrast, in rats microinfused with a vector only expressing a reporter gene, a highly significant loss of neurons occurred. By 4 hours into the reperfusion period (5 hours after ischemia onset), delivery of the Bcl-2 vector was no longer protective. These data show the efficacy of postinsult gene therapy strategies for the brain, underline the finite length of this temporal therapeutic window, and support the growing evidence attesting to the neuroprotective potential of Bcl-2.

Herpes simplex virus-based amplicon vectors have been used for gene transfer into cultured neurons and the adult CNS. Since constitutive expression of a foreign gene or overexpression of an endogenous gene may have deleterious effects, the ability to control temporal expression would be advantageous. To achieve inducible gene expression, we have incorporated the tetracycline-responsive promoter system into amplicon vectors and showed, both in vitro and in vivo, that expression can be modulated by tetracycline. Using the firefly luciferase as the reporter gene, maximal repression by tetracycline in hippocampal cultures was about 50-fold. Withdrawal of tetracycline derepressed gene expression, reaching maximal levels within 10-12 h. In contrast, addition of tetracycline to cultures without prior tetracycline exposure inhibited gene expression rapidly; luciferase activity was reduced to less than 8% within 24 h. In adult rat hippocampus, vectors expressing luciferase or the Escherichia coli lacZ were repressed by tetracycline 9- and 60-fold, respectively. Maximum gene expression from the vectors occurred 2-3 days post-infection and declined thereafter. Such decline impeded further induction of expression by withdrawing tetracycline. This study demonstrates the feasibility of incorporating a powerful inducible promoter system into HSV vectors. The development of such an inducible viral vector system for gene transfer into the adult CNS might prove to be of experimental and therapeutic value.

With its natural propensity to infect and establish life-long latency in neurons, herpes simplex virus type 1 (HSV-1) has been successfully employed by various laboratories as vectors for gene transfer into neurons. However, analysis of its cytopathic effects in vivo and in vitro has been limited. In this study, we examined the cytopathic effects of 2 HSV-1 α4 mutants (ts756 and d120) on adult rat hippocampus and striatum and of d120 on hippocampal neurons in culture. We assessed damage by stringent counting of surviving neurons after infection and demonstrated that while neither ts756 nor d120 infection resulted in any gross anatomical or behavioral changes of the animals, ts756, but not d120, produced a significant amount of damage in the CA4 cell field and dentate gyrus of the hippocampus. Thus, since crude examination is insufficient to detect subtle but significant degrees of neuron loss, the cytopathic effects of HSV or any vector system must be carefully analyzed. Furthermore, we also observed that uninfected cell lysates damaged neurons, both in vivo and in vitro. This cytotoxicity occurred within the first 24 h post-inoculation and probably arose through the activation of glutamate receptors. For the preparation of HSV vectors, purification of the virus from soluble cellular components by a simple pelleting step can significantly decrease such acute toxicity.