Incidence of valganciclovir-related leukopenia and neutropenia in solid organ transplant recipients at high risk of cytomegalovirus disease.

BACKGROUND: Valganciclovir (VGCV) prophylaxis is associated with an increased risk of hematologic side effects. We analyzed the impact of VGCV prophylaxis on leukopenia and neutropenia rates and explored risk factors for its occurrence. METHODS: Retrospective cohort study of adult cytomegalovirus (CMV)-seronegative solid organ transplantation (SOT) recipients of either CMV-seropositive (CMV D+/R-) or CMV-seronegative (CMV D-/R-) donors between July 2005 and March 2019. CMV D+/R- SOT recipients received 3-12 months of VGCV prophylaxis whereas CMV D-/R- SOT recipients received no VGCV prophylaxis. Competing risk regression was used to calculate risk factors for significant neutropenia (neutrophil count < 1000/µL). RESULTS: A total of 430 CMV-seronegative SOT recipients (median age of 52.1 years, 76.5% males) were included, of which 203 (47.2%) were CMV D+/R- and 227 (52.8%) CMV D-/R-. The unadjusted incidence rate ratio of significant neutropenia attributable to VGCV exposure in the first year post-transplant was 13.50 (95% confidence interval 7.36-27.11). Acute rejection occurred more frequently in neutropenic patients at 32.5% compared to 19.1% in those without neutropenia (p = .033). On multivariate analysis, VGCV prophylaxis for 1-90 days and 91-180 days versus no VGCV were the strongest risk factors for significant neutropenia with a sub-distribution hazard ratio of 39.6 (95% CI, 8.57-182.6) and 13.2 (95% CI, 5.46-32.0), respectively. CONCLUSIONS: VGCV prophylaxis is limited by high rates of neutropenia. Future prospective studies are needed to assess alternative CMV prophylactic strategies in SOT recipients.

Omicron BA.4/5 Neutralization and T-Cell Responses in Organ Transplant Recipients After Booster Messenger RNA Vaccine: A Multicenter Cohort Study.

BACKGROUND: In solid organ transplant (SOT) recipients, the primary vaccination series against Coronavirus Disease 2019 is 3 doses followed by boosters. We determined whether a fourth dose booster induced Omicron BA.4/5 neutralizing antibodies (nAbs) and T cells in a large multicenter cohort study. METHODS: Serum was collected 4-6 weeks post-third and post-fourth doses of messenger RNA vaccine in 222 SOT recipients. nAbs were measured using a pseudovirus neutralization assay that targeted the Omicron BA.4/5 spike protein. A subset underwent T-cell testing. RESULTS: The median age of the cohort was 63 years (interquartile range [IQR], 50-68) with 61.7% men. BA.4/5 nAb detection increased from 26.6% (59 of 222) post-third dose to 53.6% (119 of 222) post-fourth dose (P < .0001). In patients with breakthrough infection prior to the fourth dose (n = 27), nAbs were detected in 77.8% and median nAb titers were significantly higher compared with those with 4 vaccine doses alone (P < .0001). Factors associated with a low BA.4/5 neutralization response after the fourth dose were older age (odds ratio [OR], 0.96; 95% confidence interval [CI], .94-.99), mycophenolate use (OR, 0.39; 95% CI, .20-.77) and prednisone use (OR, 0.34; 95% CI, .18-.63), and vaccine type (OR, 0.72; 95% CI, .51-.99), while breakthrough infection prior to the fourth dose (OR, 3.6; 95% CI, 1.3-9.9) was associated with a greater nAb response. Polyfunctional BA.4/5-specific CD4+ T cells significantly increased after 4 doses and were identified in 76.9% of patients at a median frequency of 213/106 cells (IQR, 98-650). CONCLUSIONS: In summary, a booster significantly increases BA.4/5-specific neutralization and polyfunctional CD4+ T-cell responses, suggesting protection from severe disease even with new Omicron variants. However, SOT recipients who are older and on mycophenolate and prednisone need additional preventative strategies.

Risk Factors for Nontuberculous Mycobacteria Infections in Solid Organ Transplant Recipients: A Multinational Case-Control Study.

BACKGROUND: Risk factors for nontuberculous mycobacteria (NTM) infections after solid organ transplant (SOT) are not well characterized. Here we aimed to describe these factors. METHODS: Retrospective, multinational, 1:2 matched case-control study that included SOT recipients ≥12 years old diagnosed with NTM infection from 1 January 2008 to 31 December 2018. Controls were matched on transplanted organ, NTM treatment center, and post-transplant survival greater than or equal to the time to NTM diagnosis. Logistic regression on matched pairs was used to assess associations between risk factors and NTM infections. RESULTS: Analyses included 85 cases and 169 controls (59% male, 88% White, median age at time of SOT of 54 years [interquartile range {IQR} 40-62]). NTM infection occurred in kidney (42%), lung (35%), heart and liver (11% each), and pancreas transplant recipients (1%). Median time from transplant to infection was 21.6 months (IQR 5.3-55.2). Most underlying comorbidities were evenly distributed between groups; however, cases were older at the time of NTM diagnosis, more frequently on systemic corticosteroids and had a lower lymphocyte count (all P < .05). In the multivariable model, older age at transplant (adjusted odds ratio [aOR] 1.04; 95 confidence interval [CI], 1.01-1.07), hospital admission within 90 days (aOR, 3.14; 95% CI, 1.41-6.98), receipt of antifungals (aOR, 5.35; 95% CI, 1.7-16.91), and lymphocyte-specific antibodies (aOR, 7.73; 95% CI, 1.07-56.14), were associated with NTM infection. CONCLUSIONS: Risk of NTM infection in SOT recipients was associated with older age at SOT, prior hospital admission, receipt of antifungals or lymphocyte-specific antibodies. NTM infection should be considered in SOT patients with these risk factors.

Plasmodium knowlesi Infection in Traveler Returning to Canada from the Philippines, 2023.

A 55-year-old man sought treatment for an uncomplicated febrile illness after returning to Canada from the Philippines. A suspected diagnosis of Plasmodium knowlesi infection was confirmed by PCR, and treatment with atovaquone/proguanil brought successful recovery. We review the evolving epidemiology of P. knowlesi malaria in the Philippines, specifically within Palawan Island.

A young woman with persistent sore throat, Epstein-Barr virus, lymphadenopathy, and aberrant CD4 + CD7- T-cells.

A young woman with persistent EBV viremia and lymphocytosis had an abnormal CD4- T cell population with aberrant loss of CD7. She had a diagnosis of chronic active EBV (CAEBV), a lymphoproliferative disorder for which she ultimately required allogeneic hematopoietic stem cell transplantation.

Association between gut colonization of vancomycin-resistant enterococci and liver transplant outcomes.

BACKGROUND: Vancomycin-resistant enterococci (VRE) colonization is common in liver transplant recipients and has been associated with worse posttransplant outcomes. METHODS: We conducted a retrospective cohort study at the University of Alberta Hospital including patients who underwent a liver transplant between September 2014 and December 2017. RESULTS: Of 343 patients, 68 (19.8%) had pretransplant VRE colonization and 27 (27/275, 9.8%) acquired VRE posttransplant, 67% were males and the median age was 56.5 years. VRE colonized patients at baseline had higher MELD scores and required longer posttransplant hospitalization. VRE colonization was associated with increased risk of early acute kidney injury (AKI) (64% vs. 52%, p = .044), clinically significant bacterial/fungal infection (29% vs. 17%, p = .012) and invasive VRE infection (5% vs. 1%, p = .017). Mortality at 2 years was 13% in VRE-colonized versus 7% in noncolonized (p = .085). On multivariate analysis, VRE colonization increased the risk of posttransplant AKI (HR 1.504, 95% CI: 1.077-2.100, p = .017) and clinically significant bacterial or fungal infection at 6 months (HR 2.038, 95% CI: 1.222-3.399, p = .006), and was associated with nonsignificant trend toward increased risk of mortality at 2 years posttransplant (HR 1.974 95% CI 0.890-4.378; p = .094). CONCLUSIONS: VRE colonization in liver transplant patients is associated with increased risk of early AKI, clinically significant infections, and a trend toward increased mortality at 2 years.

Donor Graft Cytomegalovirus Serostatus and the Risk of Arterial and Venous Thrombotic Events in Seronegative Recipients After Non-Thoracic Solid Organ Transplantation.

BACKGROUND: Cytomegalovirus (CMV) is the most common opportunistic pathogen, following solid organ transplantation (SOT), that leads to direct and indirect effects. The aim of this study was to assess the impact of CMV exposure at transplantation on the rate of posttransplant thrombotic events (TEs). METHODS: We conducted a retrospective cohort study of patients transplanted at the University of Alberta Hospital between July 2005 and January 2018. We included adult SOT CMV-seronegative recipients at transplantation who received an allograft from either a seropositive donor (D+/R-) or a seronegative donor (D-/R-). RESULTS: A total of 392 SOT recipients were included: 151 (39%) liver, 188 (48%) kidney, 45 (11%) pancreas, and 8 (2%) other transplants. The mean age was 47 years, 297 (76%) were males, and 181 (46%) had a CMV D+/R- donor. Patients in the CMV D+/R- cohort were slightly older (51 years versus 48 years in the D-/R- cohort; P = .036), while other variables, including cardiovascular risk factors and pretransplant TEs, were not different between groups. Overall, TEs occurred in 35 (19%) patients in the CMV D+/R- group, versus 21 (10%) in the CMV D-/R- group, at 5 years of follow-up (P = .008); the incidence rates per 100 transplant months were 5.12 and 1.02 in the CMV D+/R- and CMV D-/R- groups, respectively (P = .003). After adjusting for potential confounders with a Cox regression model, a CMV D+/R- transplantation was independently associated with an increased risk of a TE over 5 years (adjusted hazard ratio, 3.027; 95% confidence interval, 1.669-5.488). CONCLUSIONS: A CMV D+/R- transplantation is associated with an increased risk of a TE posttransplantation.

Ruxolitinib as adjunctive therapy for secondary hemophagocytic lymphohistiocytosis: A case series.

INTRODUCTION: Hemophagocytic lymphohistiocytosis (HLH) is a cytokine storm syndrome associated with mortality rates of up to 88%. Standard therapy with high-dose glucocorticoids and etoposide used in adults is extrapolated from pediatric trials, with significant toxicity in older patients and those with poor performance status. The JAK1/2 inhibitor ruxolitinib has recently gained attention as a treatment option for HLH due to its broad cytokine-modulating abilities and safety profile. Herein we report our center's experience using ruxolitinib in the treatment of adult-onset secondary HLH. CASE SERIES: We report four patients with profound secondary HLH provoked by diverse triggers, including invasive pulmonary aspergillosis on background systemic lupus erythematosus, disseminated tuberculosis, and T-cell lymphoma treated with ruxolitinib as monotherapy or combination therapy in upfront and salvage settings. RESULTS: All four patients had rapid, sustained improvement in clinical status, inflammatory markers, and hematological cell counts followed by durable remission. Three patients developed manageable infectious complications postruxolitinib. CONCLUSIONS: This series demonstrates the effective use of JAK inhibition with ruxolitinib to control pathological immune activation in critically ill patients with secondary HLH and otherwise limited therapeutic options. JAK inhibition is also an area of urgent investigation for the treatment of cytokine storm associated with COVID-19.

Gonococcal Conjunctivitis in Adults: Case Report and Retrospective Review of Cases in Alberta, Canada, 2000-2016.

BACKGROUND: A case of gonococcal conjunctivitis (GC) prompted us to review the reported cases and treatment regimens of GC in Alberta, Canada. METHODS: Gonococcal cases reported from 2000 to 2016 were extracted from the provincial sexually transmitted infection reporting database. The diagnosis of GC was based on a positive culture and/or nucleic acid amplification test from the eye. RESULTS: A total of 45 cases of GC were reported in adults. Three quarters (75.6%; n = 34) of the cases were diagnosed using culture, 57.8% (n = 26) of cases were among men, and 55.5% (n = 25) were diagnosed since 2014. Very few (13.3%; n = 6) of the cases were treated according to current Canadian Guidelines on Sexually Transmitted Infections, using 2 g of ceftriaxone in combination with azithromycin or doxycycline. Results of test of cures were available for 15.6% (n = 7) of the cases and occurred within 10 to 79 days (median = 26 days) after treatment; all were negative. CONCLUSIONS: Gonococcal conjunctivitis was relatively uncommon in our region, but given its potential for severe manifestations and sequelae coupled with the rising rates of gonorrhea; it remains important to consider this diagnosis in sexually active individuals presenting with purulent conjunctivitis. Additional studies are needed to inform treatment recommendations and to evaluate outcomes of infection.

When medicine transforms art.

A 40-year-old female with a history of type 1 diabetes mellitus and solitary pancreas transplant, presented with pancreatic graft rejection 1-year post-transplant. Incidentally, a 1.1 cm right lower lobe cavity was identified during her workup. Given the augmentation of immunosuppression, voriconazole was empirically started for possible invasive pulmonary aspergillosis. As the patient was a painter, this resulted in a significant change in the colors of her paintings. Ultimately, she was diagnosed with pulmonary coccidioidomycosis and her visual disturbances resolved after the voriconazole was changed to fluconazole. Voriconazole causes visual disturbances in 20%-30% of the patients most commonly phototopsias; dyschromatopsias typically involving the tritan axis have also been reported. This case illustrates well the potential impact of voriconazole on spectral sensitivity and color perception.

Association between frailty and 30-day outcomes after discharge from hospital.

BACKGROUND: Readmissions after hospital discharge are common and costly, but prediction models are poor at identifying patients at high risk of readmission. We evaluated the impact of frailty on readmission or death within 30 days after discharge from general internal medicine wards. METHODS: We prospectively enrolled patients discharged from 7 medical wards at 2 teaching hospitals in Edmonton. Frailty was defined by means of the previously validated Clinical Frailty Scale. The primary outcome was the composite of readmission or death within 30 days after discharge. RESULTS: Of the 495 patients included in the study, 162 (33%) met the definition of frailty: 91 (18%) had mild, 60 (12%) had moderate, and 11 (2%) had severe frailty. Frail patients were older, had more comorbidities, lower quality of life, and higher LACE scores at discharge than those who were not frail. The composite of 30-day readmission or death was higher among frail than among nonfrail patients (39 [24.1%] v. 46 [13.8%]). Although frailty added additional prognostic information to predictive models that included age, sex and LACE score, only moderate to severe frailty (31.0% event rate) was an independent risk factor for readmission or death (adjusted odds ratio 2.19, 95% confidence interval 1.12-4.24). INTERPRETATION: Frailty was common and associated with a substantially increased risk of early readmission or death after discharge from medical wards. The Clinical Frailty Scale could be useful in identifying high-risk patients being discharged from general internal medicine wards.

SARS-CoV-2 Variants Omicron BA.4/5 and XBB.1.5 Significantly Escape T Cell Recognition in Solid-organ Transplant Recipients Vaccinated Against the Ancestral Strain.

BACKGROUND: Immune-suppressed solid-organ transplant recipients (SOTRs) display impaired humoral responses to COVID-19 vaccination, but T cell responses are incompletely understood. SARS-CoV-2 variants Omicron BA.4/5 (BA.4/5) and XBB.1.5 escape neutralization by antibodies induced by vaccination or infection with earlier strains, but T cell recognition of these lineages in SOTRs is unclear. METHODS: We characterized Spike-specific T cell responses to ancestral SARS-CoV-2 and BA.4/5 peptides in 42 kidney, liver, and lung transplant recipients throughout a 3- or 4-dose ancestral Spike mRNA vaccination schedule. As the XBB.1.5 variant emerged during the study, we tested vaccine-induced T cell responses in 10 additional participants using recombinant XBB.1.5 Spike protein. Using an optimized activation-induced marker assay, we quantified circulating Spike-specific CD4 + and CD8 +  T cells based on antigen-stimulated expression of CD134, CD69, CD25, CD137, and/or CD107a. RESULTS: Vaccination strongly induced SARS-CoV-2-specific T cells, including BA.4/5- and XBB.1.5-reactive T cells, which remained detectable over time and further increased following a fourth dose. However, responses to BA.4/5 (1.34- to 1.67-fold lower) XBB.1.5 (2.0- to 18-fold lower) were significantly reduced in magnitude compared with ancestral strain responses. CD4 + responses correlated with anti-receptor-binding domain antibodies and predicted subsequent antibody responses in seronegative individuals. Lung transplant recipients receiving prednisone and older adults displayed weaker responses. CONCLUSIONS: Ancestral strain vaccination stimulates BA.4/5 and XBB.1.5-cross-reactive T cells in SOTRs, but at lower magnitudes. Antigen-specific T cells can predict future antibody responses. Our data support monitoring both humoral and cellular immunity in SOTRs to track COVID-19 vaccine immunogenicity against emerging variants.

Severe hypercalcemia as a result of disseminated Candida krusei infection.

Candida krusei disseminated infection is a rare complication of protracted neutropenia. Herein, we report a case of a 31-year-old male with relapsed acute myeloid leukemia who developed Candida krusei fungemia with cutaneous, ocular, splenic, renal, bone marrow and osseous involvement leading to severe hypercalcemia, treated with parenteral antifungals followed by oral ibrexafungerp.

Impact of recipient age on mortality among Cytomegalovirus (CMV)-seronegative lung transplant recipients with CMV-seropositive donors.

BACKGROUND: Cytomegalovirus (CMV)-seronegative lung transplant recipients (LTRs) with seropositive donors (CMV D+/R-) have the highest mortality of all CMV serostatuses. Due to immunosenescence and other factors, we hypothesized CMV D+/R- status might disproportionately impact older LTRs. Thus, we investigated whether recipient age modified the relationship between donor CMV status and mortality among CMV-seronegative LTRs. METHODS: Adult, CMV-seronegative first-time lung-only recipients were identified through the Scientific Registry of Transplant Recipients between May 2005 and December 2019. We used adjusted multivariable Cox regression to assess the relationship of donor CMV status and death. Interaction between recipient age and donor CMV was assessed via likelihood ratio testing of nested Cox models and by the relative excess risk due to interaction (RERI) and attributable proportion (AP) of joint effects. RESULTS: We identified 11,136 CMV-seronegative LTRs. The median age was 59 years; 65.2% were male, with leading transplant indication of idiopathic pulmonary fibrosis (35.6%); and 60.8% were CMV D+/R-. In multivariable modeling, CMV D+/R- status was associated with 27% increased hazard of death (adjusted hazard ratio: 1.27, 95% confidence interval: 1.21-1.34) compared to CMV D-/R-. Recipient age ≥60 years significantly modified the relationship between donor CMV-seropositive status and mortality on the additive scale, including RERI 0.24 and AP 11.4% (p = 0.001), that is, the interaction increased hazard of death by 0.24 and explained 11.4% of mortality in older CMV D+ recipients. CONCLUSIONS: Among CMV-seronegative LTRs, donor CMV-seropositive status confers higher risk of posttransplant mortality, which is amplified in older recipients. Future studies should define optimal strategies for CMV prevention and management in older D+/R- LTRs.

Clinical Management and Outcomes of Nontuberculous Mycobacterial Infections in Solid Organ Transplant Recipients: A Multinational Case-control Study.

BACKGROUND: The management and outcomes of nontuberculous mycobacterial (NTM) infections in solid organ transplant (SOT) recipients are poorly characterized. We aimed to describe the management and 1-y mortality of these patients. METHODS: Retrospective, multinational, 1:2 matched case-control study included SOT recipients aged 12 y old or older diagnosed with NTM infection between January 1, 2008, and December 31, 2018. Controls were matched on transplanted organs, NTM treatment center, and posttransplant survival at least equal to the time to NTM diagnosis. The primary aim was 1-y mortality after NTM diagnosis. Differences between cases and controls were compared using the log-rank test, and Cox regression models were used to identify factors associated with mortality at 12 mo among cases. RESULTS: In 85 patients and 169 controls, the median age at the time of SOT was 54 y (interquartile range, 40-62 y), 59% were men, and the lungs were the most common site of infection after SOT (57.6%). One-year mortality was significantly higher in cases than in controls (20% versus 3%; P < 0.001), and higher mortality was associated with lung transplantation (hazard ratio 3.27; 95% confidence interval [1.1-9.77]; P = 0.034). Median time (interquartile range) from diagnosis to treatment initiation (20 [4-42] versus 11 [3-21] d) or the reduction of net immunosuppression (36% versus 45%, hazard ratio 1.35 [95% CI, 0.41-4.43], P = 0.618) did not differ between survivors and those who died. CONCLUSIONS: NTM disease in SOT recipients is associated with a higher mortality risk, especially among lung transplant recipients. Time to NTM treatment and reduction in net immunosuppression were not associated with mortality.

Transplantid.net: A Pilot Crowdsourced, Living, Online Library of Resources for the Teaching and Practice of Transplant Infectious Diseases.

The field of transplant infectious diseases is rapidly evolving, presenting a challenge for clinical practice and trainee education. Here we describe the construction of transplantid.net, a free online library, crowdsourced and continuously updated for the dual purpose of point-of-care evidence-based management and teaching.