Best Practices in the Management of Clostridioides difficile Infection in Developing Nations.

Clostridioides difficile infection (CDI) is a well-known cause of hospital-acquired infectious diarrhea in developed countries, though it has not been a top priority in the healthcare policies of developing countries. In the last decade, several studies have reported a wide range of CDI rates between 1.3% and 96% in developing nations, raising the concern that this could represent a healthcare threat for these nations. This review defines developing countries as those with a human development index (HDI) below 0.8. We aim to report the available literature on CDI epidemiology, diagnostics, management, and prevention in developing countries. We identify limitations for CDI diagnosis and management, such as limited access to CDI tests and unavailable oral vancomycin formulation, and identify opportunities to enhance CDI care, such as increased molecular test capabilities and creative solutions for CDI. We also discuss infection prevention strategies, including antimicrobial stewardship programs and opportunities emerging from the COVID-19 pandemic, which could impact CDI care.

Efficacy of Fecal Microbiota, Live-jslm (REBYOTA®), Among Patients Exposed to Non-Clostridioides difficile Infection Antibiotics: Post Hoc Subgroup Analysis of a Phase 2 Open-Label Study.

Background: Antibiotic use is a major risk factor for recurrent Clostridioides difficile infection (CDI) due to the associated disruption in gut microbiota. Fecal microbiota, live-jslm (REBYOTA®; RBL, previously RBX2660), is the first microbiota-based live biotherapeutic approved by the US Food and Drug Administration to prevent recurrent CDI in adults following standard-of-care antibiotic treatment. To investigate the impact of non-CDI antibiotics on the durability of RBL, a subgroup analysis was conducted on PUNCH™ Open-Label study participants who received non-CDI antibiotics during the period between RBL administration and up to 2 years after. Methods: Participants in PUNCH™ Open-Label who received non-CDI antibiotics after RBL administration were included in this subgroup analysis. Treatment response was defined as the absence of CDI diarrhea needing retreatment at the last evaluable time point (8 weeks, 6 months, 1 year, or 2 years) after RBL administration. Results: Among participants from PUNCH™ Open-Label, 43 received non-CDI antibiotics after RBL administration but before CDI recurrence as evaluated over a 2-year period. Across all evaluable time points, 86% (37/43) of participants had a treatment response regardless of when non-CDI antibiotic exposure occurred. Treatment response was sustained for a median 470 days (IQR, 212-648) from the first day of non-CDI antibiotic use. Most participants (5/6) with CDI recurrences received a high-risk antibiotic. Conclusions: RBL remained efficacious in participants with a history of recurrent CDI after subsequent non-CDI antibiotic exposure. Clinical Trials Registration: NCT02589847 (https://clinicaltrials.gov/study/NCT02589847).

Influence of induction therapy and antiretroviral regimen on outcomes in kidney transplant recipients living with human immunodeficiency.

PURPOSE: Kidney transplantation has a survival benefit for people with human immunodeficiency virus (HIV) and end-stage kidney disease, however increased rates of rejection remain an issue. Questions remain regarding the impact of induction immunosuppression therapy and antiretroviral (ARV) choice on long-term outcomes. METHODS: We performed a multicenter retrospective analysis of outcomes in recipients with HIV who received kidneys from donors without HIV transplanted between 2004 and 2019. The association between induction and ARV regimens and long-term outcomes including rejection, graft, and recipient survival over 5 years was investigated using Cox regression modeling. RESULTS: Seventy-eight kidney transplants (KT) performed in 77 recipients at five US transplant centers were included, with median follow up of 7.1 (4.3-10.7) years. Overall recipient and graft survival were 83% and 67%, respectively. Rejection occurred in 37% (29/78). Recipients with rejection were more likely to be younger, recipients of deceased donor organs, and Black. Receipt of rabbit anti-thymocyte globulin (rATG) induction without protease-inhibitor (PI)-based ARVs was associated with 83% lower risk of rejection (adjusted hazard ratio (aHR) 0.17 (95% CI 0.05-0.63), p =.007) and a non-statistically significantly lower risk of graft failure (aHR 0.18 (0.03-1.16), p =.07) when compared to those who received other induction and ARV combinations. CONCLUSIONS: In this multicenter retrospective study, we found a trend toward lower rejection and improved graft survival among those who received both rATG for induction and PI-sparing ARVs.

Epidemiology and outcomes associated with enterococcal blood stream infection among liver and kidney transplant recipients.

Bloodstream infections (BSIs) account for 18% of bacterial infections in the first year after solid organ transplantation (SOT). Enterococcus accounts for up to 20% of BSIs in this population, with vancomycin-resistant enterococcus (VRE) posing a particular risk. This is a retrospective, case-control study of adult liver and kidney transplant recipients between 01/01/2016 and 06/30/2021 that characterizes the epidemiology and outcomes of enterococcal BSIs in liver and kidney transplantations at a single institution. Subjects with an enterococcal BSI within the first 6 months post-transplant were compared to those with non-enterococcal BSIs in the same period. We identified 26 subjects with enterococcal BSIs and 28 controls with non-enterococcal BSIs (n = 54; 10.3%). Cases were mostly liver transplant recipients (n = 20; 77%) with a median MELD at transplant of 33 (range 14-43); controls included 14 KT recipients (50%). Groups differed significantly (all p < .05) by factors including perioperative transfusion requirements, need for reoperation, and number of interventions post-transplant. Cases had a median time of 25.5 days to infection and controls 100.5 days (p < .0001). There were no differences in 1-year mortality between the groups. Enterococcus faecium was the predominant species of Enterococcus (n = 23; 88.5%), with a majority (91.3%) of the isolates being VRE. In our liver and kidney transplants, enterococcal BSIs occurred early among liver transplant recipients. The high incidence of VRE among E. faecium isolates in this population warrants further investigation into the optimal approach to empiric antimicrobials for bacteremia in the early post-transplant period.

Single-Center Outcomes of Epstein-Barr Virus DNAemia in Adult Solid Organ Transplant Recipients.

Background: Immunosuppression in solid organ transplantation (SOT) increases the risk of Epstein-Barr virus (EBV) DNAemia, which may herald development of posttransplant lymphoproliferative disease (PTLD). Few studies have characterized the incidence, risk factors, and clinical impact of EBV DNAemia in adult SOT recipients (SOTR). Methods: A single-center, retrospective review of adult (≥18 years) SOTR between 01 January 2015 and 31 December 2019 was conducted. Patients were stratified by the primary study endpoint of development of EBV DNAemia (whole blood EBV DNA PCR > 200 copies/mL). Secondary endpoints included development of PTLD, reduction in immunosuppression (RIS), use of pre-emptive therapy, and all-cause mortality. Results: Among 442 adult SOTR, the predominant transplant organs were the kidney (258, 58%) and liver (141, 31.9%). EBV serostatus in most subjects (430, 97%) was classified as intermediate risk (R+). Eight subjects (2%) were high risk (donor (D+/R-), and 4 (1%) were low risk (D-/R-). The overall incidence of EBV DNAemia was 4.1% (18/442) with a median time to detection of 14 months (range 3-60). The highest proportion of DNAemia was observed in D+/R- subjects (37.5%; p < 0.001). Development of PTLD was significantly associated with EBV DNAemia and occurred in 3/18 patients with DNAemia (16.7%) vs. 3/424 (0.7%) without DNAemia (p < 0.001). All patients with PTLD were managed with RIS and rituximab. Conclusion: We observed that EBV D+/R- serostatus and development of sustained EBV DNAemia were high risk features associated with subsequent development of PTLD in our cohort of adult SOTR.

Adjunctive glucocorticoid therapy for Pneumocystis jirovecii pneumonia in solid organ transplant recipients: A multicenter cohort, 2015-2020.

Solid organ transplant recipients (SOTRs) frequently receive adjunctive glucocorticoid therapy (AGT) for Pneumocystis jirovecii pneumonia (PJP). This multicenter cohort of SOTRs with PJP admitted to 20 transplant centers in Canada, the United States, Europe, and Australia, was examined for whether AGT was associated with a lower rate of all-cause intensive care unit (ICU) admission, 90-day death, or a composite outcome (ICU admission or death). Of 172 SOTRs with PJP (median [IQR] age: 60 (51.5-67.0) years; 58 female [33.7%]), the ICU admission and death rates were 43.4%, and 20.8%, respectively. AGT was not associated with a reduced risk of ICU admission (adjusted odds ratio [aOR] [95% CI]: 0.49 [0.21-1.12]), death (aOR [95% CI]: 0.80 [0.30-2.17]), or the composite outcome (aOR [95% CI]: 0.97 [0.71-1.31]) in the propensity score-adjusted analysis. AGT was not significantly associated with at least 1 unit of the respiratory portion of the Sequential Organ Failure Assessment score improvement by day 5 (12/37 [32.4%] vs 39/111 [35.1%]; P = .78). We did not observe significant associations between AGT and ICU admission or death in SOTRs with PJP. Our findings should prompt a reevaluation of routine AGT administration in posttransplant PJP treatment and highlight the need for interventional studies.

Tixagevimab-Cilgavimab Decreases the Rate of SARS-CoV-2 Infection Among Solid Organ Transplant Recipients.

BACKGROUND: SARS-CoV-2 infection in solid organ transplant (SOT) recipients is associated with high morbidity and mortality. Tixagevimab/cilgavimab monoclonal antibodies were previously authorized for pre-exposure prophylaxis for immunocompromised individuals. We aimed to determine if tixagevimab/cilgavimab could prevent breakthrough SARS-CoV-2 infection in SOT recipients. MATERIAL AND METHODS: We conducted a prospective single-center study of SOT recipients who received tixagevimab/cilgavimab compared with those who did not. Demographics, type of transplant, immunosuppression regimen, COVID-19 vaccination status, and tixagevimab/cilgavimab administration data were collected. Participants were interviewed for 6 months or until they tested positive for SARS-CoV-2, whichever came first. Kaplan-Meier SARS-CoV-2-free survival curves were created based on the tixagevimab/cilgavimab administration date and SARS-CoV-2 infection. The log-rank test was used for comparison. Univariate and multivariate Cox regression models were constructed. RESULTS: The study cohort included 323 patients. Two hundred forty-eight received tixagevimab/cilgavimab, and 75 did not (control). COVID-19 vaccination rate was higher among tixagevimab/cilgavimab recipients than nontixagevimab/cilgavimab recipients (99.6% vs 92.0%; P < .001). Twenty-six patients in the tixagevimab/cilgavimab group (10.5%) and 23 in the control group (30.7%) tested positive for SARS-CoV-2 infection (P < .001). In a multivariate analysis, receipt of tixagevimab/cilgavimab and duration from transplant were both associated with reduced risk of SARS-CoV-2 infection (hazard ratio 0.431; 95% CI 0.224-0.828 and hazard ratio 0.917; 95% CI 0.861-0.978, respectively). CONCLUSION: During the study period, SOT recipients who received tixagevimab/cilgavimab had a significantly lower rate of SARS-CoV-2 infection. There were no differences in symptom frequency, illness severity, hospitalization rate, or treatment of SARS-CoV-2 infection.

How Would You Manage This Patient With Clostridioides difficile Infection? : Grand Rounds Discussion From Beth Israel Deaconess Medical Center.

The Infectious Diseases Society of America/Society for Healthcare Epidemiology of America and the American College of Gastroenterology recently released updated guidelines on management of patients with Clostridioides difficile infection. Although these 2 guidelines generally agree, there are a few important differences in their advice to clinicians. In these rounds, 2 experts, an infectious diseases specialist and a gastroenterologist, discuss antibiotic treatment options for nonsevere disease, the role of fecal microbiota transplantation for fulminant disease, and the use of bezlotoxumab to prevent recurrence in the context of Ms. C, a 48-year-old woman with fulminant C difficile infection.

Redefining Clostridioides difficile infection antibiotic response and clinical outcomes.

With the approval and development of narrow-spectrum antibiotics for the treatment of Clostridioides difficile infection (CDI), the primary endpoint for treatment success of CDI antibiotic treatment trials has shifted from treatment response at end of therapy to sustained response 30 days after completed therapy. The current definition of a successful response to treatment (three or fewer unformed bowel movements [UBMs] per day for 1-2 days) has not been validated, does not reflect CDI management, and could impair assessments for successful treatment at 30 days. We propose new definitions to optimise trial design to assess sustained response. Primarily, we suggest that the initial response at the end of treatment be defined as (1) three or fewer UBMs per day, (2) a reduction in UBMs of more than 50% per day, (3) a decrease in stool volume of more than 75% for those with ostomy, or (4) attainment of bowel movements of Bristol Stool Form Scale types 1-4, on average, by day 2 after completion of primary CDI therapy (ie, assessed on day 11 and day 12 of a 10-day treatment course) and following an investigator determination that CDI treatment can be ceased.

Preservation of the Innate Immune Response to Clostridioides difficile Infection in Hospitalized Immunocompromised Patients.

Background: Clostridioides difficile infection (CDI) immune response is influenced by the innate and adaptive (humoral) immune systems. Our prior research found attenuated humoral responses to C difficile in immunocompromised hosts (ICHs) with CDI. We sought to evaluate whether the innate immune response to CDI was influenced by ICH status. Methods: We conducted a prospective study of hospitalized adults with CDI (acute diarrhea, positive C difficile stool nucleic acid amplification testing [NAAT], and decision to treat), with and without immunosuppression and measured a panel of cytokines (granulocyte colony-stimulating factor [G-CSF], interleukin [IL]-10, IL-15, IL-1ß, IL-4, IL-6, IL-8, and tumor necrosis factor-α) in blood and stool at CDI diagnosis. Results were compared with measurements from a cohort of asymptomatic carrier patients (ASCs) (NAAT positive, without diarrhea) with and without immunocompromise. Results: One hundred twenty-three subjects (42 ICHs, 50 non-ICHs, 31 ASCs) were included. Median values for blood and stool cytokines were similar in ICH versus non-ICH CDI subjects. In blood, G-CSF, IL-10, IL-15, IL-6, and IL-8 were higher in both groups of CDI subjects versus the ASC cohort (P < .05). In stool, IL-1ß and IL-8 were higher in both groups of CDI subjects versus the ASC cohort (P < .05). Median stool concentrations of IL-1ß demonstrated significant differences between the groups (ICHs, 10.97 pg/mL; non-ICHs, 9.71 pg/mL; and ASCs, 0.56 pg/mL) (P < .0001). Conclusions: In this small exploratory analysis, ICH status did not significantly impact blood and fecal patterns of cytokines in humans at the diagnosis of CDI, suggesting that the innate immune response to C difficile may be conserved in immunocompromised patients.

Stool Interleukin-1ß Differentiates Clostridioides difficile Infection (CDI) From Asymptomatic Carriage and Non-CDI Diarrhea.

BACKGROUND: Despite advances in the understanding and diagnosis of Clostridioides difficile infection (CDI), clinical distinction within the colonization-infection continuum remains an unmet need. METHODS: By measuring stool cytokines and antitoxin antibodies in well-characterized cohorts of CDI (diarrhea, nucleic acid amplification test [NAAT] positive), non-CDI diarrhea (NCD; diarrhea, NAAT negative), asymptomatic carriers (ASC; no diarrhea, NAAT positive) and hospital controls (CON; no diarrhea, NAAT negative), we aim to discover novel biological markers to distinguish between these cohorts. We also explore the relationship of these stool cytokines and antitoxin antibody with stool toxin concentrations and disease severity. RESULTS: Stool interleukin (IL) 1ß, stool immunoglobulin A (IgA), and immunoglobulin G (IgG) anti-toxin A had higher (P < .0001) concentrations in CDI (n = 120) vs ASC (n = 43), whereas toxins A, B, and fecal calprotectin did not. Areas under the receiver operating characteristic curve (ROC-AUCs) for IL-1ß, IgA, and IgG anti-toxin A were 0.88, 0.83, and 0.83, respectively. A multipredictor model including IL-1ß and IgA anti-toxin A achieved an ROC-AUC of 0.93. Stool IL-1ß concentrations were higher in CDI compared to NCD (n = 75) (P < .0001) and NCD + ASC+ CON (CON, n = 75) (P < .0001), with ROC-AUCs of 0.83 and 0.86, respectively. Stool IL-1ß had positive correlations with toxins A (ρA = +0.55) and B (ρB = +0.49) in CDI (P < .0001) but not in ASC (P > .05). CONCLUSIONS: Stool concentrations of the inflammasome pathway, proinflammatory cytokine IL-1ß, can accurately differentiate CDI from asymptomatic carriage and NCD, making it a promising biomarker for CDI diagnosis. Significant positive correlations exist between stool toxins and stool IL-1ß in CDI but not in asymptomatic carriers.

Insights From the Eye for Patients With Kidney Transplant.

The eye and the kidney share structural and developmental similarities on a cellular and clinical level, and they are often affected by the same disease processes. Performing an eye exam to look for signs of conditions such as hypertension and diabetes can provide a helpful window into the health of the kidney. Patients with kidney transplants (KT) are a unique population that require close monitoring. These patients are maintained on a number of immunosuppressive medications and may face complications such as medication side effects, infections, and graft rejection. Patients with KT are at higher risk of both infectious and noninfectious eye conditions related to underlying systemic disease or use of immunosuppressive medications. Screening for eye conditions is important because preserving visual function is integral to quality of life, and also because the eye exam can help with early detection and treatment of systemic conditions. Here we describe some of the common eye findings and conditions in patients with KT. We recommend that patients with KT receive annual eye exams, and we hope that the information provided here can help nephrologists become more familiar with eye findings and identify situations where a referral to ophthalmology is warranted.

Higher In Vivo Fecal Concentrations of Clostridioides difficile Toxins A and B in Patients With North American Pulsed-Field Gel Electrophoresis Type 1/Ribotype 027 Strain Infection.

Ultrasensitive, quantitative Clostridioides difficile stool toxin measurement demonstrated significantly higher concentrations of toxins A and B in patients infected with the North American pulsed-field gel electrophoresis type 1/ribotype 027 (NAP-1/027) strain compared with other strains, providing in vivo confirmation of the in vitro association between NAP-1/027 and elevated toxin production.

American Society for Transplantation and Cellular Therapy Series: #5-Management of Clostridioides difficile Infection in Hematopoietic Cell Transplant Recipients.

The Practice Guidelines Committee of the American Society for Transplantation and Cellular Therapy partnered with its Transplant Infectious Disease Special Interest Group to update its 2009 compendium-style infectious disease guidelines for hematopoietic cell transplantation (HCT). A completely new approach was taken with the goal of better serving clinical providers by publishing each standalone topic in the infectious disease series as a concise format of frequently asked questions (FAQ), tables, and figures. Adult and pediatric infectious disease and HCT content experts developed and then answered FAQs and finalized topics with harmonized recommendations that were made by assigning an A through E strength of recommendation paired with a level of supporting evidence graded I through III. This fifth guideline in the series focuses on Clostridioides difficile infection with FAQs that address the prevalence, incidence, clinical features, colonization versus infection, clinical complications, diagnostic considerations, pharmacological therapies for episodic or recurrent infection, and the roles of prophylactic antibiotics, probiotics, and fecal microbiota transplantation.

Comparative outcomes for mature T-cell and NK/T-cell lymphomas in people with and without HIV and to AIDS-defining lymphomas.

There are no studies comparing the prognosis for mature T-cell lymphoma (TCL) in people with HIV (PWH) to people without HIV (PWoH) and to AIDS-defining B-cell lymphomas (A-BCLs) in the modern antiretroviral therapy era. North American AIDS Cohort Collaboration on Research and Design and Comprehensive Oncology Measures for Peripheral T-cell Lymphoma Treatment are cohorts that enroll patients diagnosed with HIV and TCL, respectively. In our study, 52, 64, 101, 500, and 246 PWH with histologic confirmation of TCL, primary central nervous system lymphoma, Burkitt's lymphoma, diffuse large B-cell lymphoma (DLBCL), and Hodgkin's lymphoma (HL), respectively, and 450 TCLs without HIV were eligible for analysis. At the time of TCL diagnosis, anaplastic large-cell lymphoma (ALCL) was the most common TCL subtype within PWH. Although PWH with TCL diagnosed between 1996 and 2009 experienced a low 5-year survival probability at 0.23 (95% confidence interval [CI]: 0.13, 0.41), we observed a marked improvement in their survival when diagnosed between 2010 and 2016 (0.69; 95% CI: 0.48, 1; P = .04) in contrast to TCLs among PWoH (0.45; 95% CI: 0.41, 0.51; P = .53). Similarly, PWH with ALCLs diagnosed between 1996 and 2009 were associated with a conspicuously inferior 5-year survival probability (0.17; 95% CI: 0.07, 0.42) and consistently lagged behind A-BCL subtypes such as Burkitt's (0.43; 95% CI:0.33, 0.57; P = .09) and DLBCL (0.17; 95% CI: 0.06, 0.46; P = .11) and behind HL (0.57; 95% CI: 0.50, 0.65; P < .0001). Despite a small number, those diagnosed between 2010 and 2016 experienced a remarkable improvement in survival (0.67; 95% CI: 0.3, 1) in comparison with PWoH (0.76; 95% CI: 0.66, 0.87; P = .58). Thus, our analysis confirms improved overall survival for aggressive B- and T-cell malignancies among PWH in the last decade.

Ultrasensitive and Quantitative Toxin Measurement Correlates With Baseline Severity, Severe Outcomes, and Recurrence Among Hospitalized Patients With Clostridioides difficile Infection.

BACKGROUND: Stool toxin concentrations may impact Clostridioides difficile infection (CDI) severity and outcomes. We correlated fecal C difficile toxin concentrations, measured by an ultrasensitive and quantitative assay, with CDI baseline severity, attributable outcomes, and recurrence. METHODS: We enrolled 615 hospitalized adults (≥18 years) with CDI (acute diarrhea, positive stool nucleic acid amplification testing, and decision to treat). Baseline stool toxin A and B concentrations were measured by single molecule array. Subjects were classified by baseline CDI severity (4 scoring methods) and outcomes within 40 days (death, intensive care unit stay, colectomy, and recurrence). RESULTS: Among 615 patients (median, 68.0 years), in all scoring systems, subjects with severe baseline disease had higher stool toxin A+B concentrations than those without (P < .01). Nineteen subjects (3.1%) had a severe outcome primarily attributed to CDI (group 1). This group had higher median toxin A+B (14 303 pg/mL [interquartile range, 416.0, 141 967]) than subjects in whom CDI only contributed to the outcome (group 2, 163.2 pg/mL [0.0, 8423.3]), subjects with severe outcome unrelated to CDI (group 3, 158.6 pg/mL [0.0, 1795.2]), or no severe outcome (group 4, 209.5 pg/mL [0.0, 8566.3]) (P = .003). Group 1 was more likely to have detectable toxin (94.7%) than groups 2-4 (60.5%-66.1%) (P = .02). Individuals with recurrence had higher toxin A+B (2266.8 pg/mL [188.8, 29411]) than those without (154.0 pg/mL [0.0, 5864.3]) (P < .001) and higher rates of detectable toxin (85.7% versus 64.0%, P = .004). CONCLUSIONS: In CDI patients, ultrasensitive stool toxin detection and concentration correlated with severe baseline disease, severe CDI-attributable outcomes, and recurrence, confirming the contribution of toxin quantity to disease presentation and clinical course.

Humoral Immune Response to Clostridioides difficile Toxins A and B in Hospitalized Immunocompromised Patients With C difficile Infection.

BACKGROUND: The humoral immune response to Clostridioides difficile toxins in C difficile infection (CDI) is incompletely characterized in immunocompromised hosts (ICHs). METHODS: We conducted a prospective study of hospitalized adults with CDI, with and without immunosuppression (hematologic malignancy, active solid tumor, solid organ or stem cell transplant, inflammatory bowel disease, autoimmune disease, congenital or acquired immunodeficiency, asplenia, chronic receipt of high-dose steroids, or receipt of immunosuppressing medications within 12 months). Serum and stool antibody concentrations of immunoglobulin (Ig)M, IgG, and IgA to C difficile toxins A and B at treatment days 0, 3, and 10-14 were compared. RESULTS: Ninety-eight subjects (47 ICH; 51 non-ICH) were enrolled. Baseline serum antitoxin A and B antibody levels were similar. At day 3, ICHs demonstrated lower serum levels of antitoxin A IgG, antitoxin A IgA, and antitoxin B IgA (all P < .05). At day 10-14, lower antitoxin A IgG concentrations were observed in ICHs (ICH, 21 enzyme-linked immunosorbent assay [ELISA] units; interquartile range [IQR], 16.4-44.6) compared with non-ICH subjects (49.0 ELISA units; IQR, 21.5-103; P = .045). In stool, we observed lower concentrations of antitoxin B IgA antibodies at baseline and at day 3 for ICH subjects, with a notable difference in concentrations of antitoxin B IgA at day 3 (ICH, 6.7 ELISA units [IQR, 1.9-13.9] compared with non-ICH, 18.1 ELISA units [IQR, 4.9-31.7]; P = .003). CONCLUSIONS: The ICHs with CDI demonstrated lower levels of C difficile antitoxin antibodies in serum and stool during early CDI therapy compared with non-ICHs. These data provide insight into the humoral response to CDI in ICHs.

Case Report: Refractory Cryptosporidiosis after CAR T-Cell Therapy for Lymphoma.

Cryptosporidial diarrhea is uncommon in immunocompetent individuals, more often seen in severely immunocompromised patients. Severe refractory cases have been described in patients with HIV/AIDS before the advent of modern antiretroviral therapy due to an inability to mount an adequate cellular immune response. We describe an 85-year-old patient post-chimeric antigen receptor T-cell therapy relapsed lymphoma who developed refractory Cryptosporidium spp. diarrhea in the setting of persistent CD4+ cytopenia. Despite receiving multiple antiparasitic agents, including failure of a prolonged course of nitazoxanide, the patient experienced persistent symptoms for 9 months with repeatedly positivity stool Cryptosporidium spp. direct fluorescent antibody (DFA) test. We highlight this case of refractory Cryptosporidium spp. and the importance of recognizing the pathogen in a non-HIV-infected immunosuppressed host.

Safety and efficacy of intravenously administered cidofovir in adult haematopoietic cell transplant recipients: a retrospective multicentre cohort study.

OBJECTIVES: To evaluate the safety and efficacy of cidofovir for the treatment of double-stranded DNA (dsDNA) viral infections following allogeneic haematopoietic cell transplant (HCT). METHODS: This was a retrospective multicentre cohort study including adult HCT recipients who received ≥1 dose of IV-administered cidofovir for any dsDNA viral infection from 2006 to 2019. The objectives were to describe the rate of and risk factors for nephrotoxicity and virological response by the end of treatment (EOT). RESULTS: We included 165 patients from nine centres. Cidofovir was administered at 5 mg/kg/week (N = 115; 69.7%), 1 mg/kg/week (18; 10.9%), 3 mg/kg/week (12; 7.3%) or 1 mg/kg three times/week (11; 6.7%). Cidofovir was administered for adenovirus, cytomegalovirus (CMV) and BK virus infection in 75 (45.5%), 64 (38.8%) and 51 (30.9%) patients, respectively. Among 158 patients with renal function data at baseline and EOT, 40 (25.3%) developed nephrotoxicity. In multivariable analyses, age (OR 1.04; P = 0.05), weight (OR 1.05; P = 0.01), CMV infection (OR 3.6; P = 0.02), liposomal amphotericin B (OR 8.06; P = 0.05) and IV voriconazole/posaconazole (OR 13.0; P = 0.003) were predictors of nephrotoxicity. Creatinine concentration was significantly higher at EOT (1.16 ±â€Š0.95 mg/dL) compared with baseline (0.91 ±â€Š0.39 mg/dL; P < 0.001), but improved by 2 weeks (0.91 ±â€Š0.84 mg/dL; P = 0.007) and 4 weeks (0.96 ±â€Š0.89 mg/dL; P = 0.03) post-EOT. Median viral load significantly declined for patients with adenovirus DNAaemia by EOT (P < 0.0001) and for patients with CMV DNAaemia by EOT + 4 weeks (P = 0.003), but not for patients with BK virus DNAaemia. CONCLUSIONS: One in four HCT recipients treated with IV cidofovir developed largely reversible nephrotoxicity. Careful selection of patients and close follow-up of renal function may minimize toxicity.