Successful Treatment of Prolonged Severe Acute Respiratory Syndrome Coronavirus 2 Infection in Patients With Immunodeficiency With Extended Nirmatrelvir/Ritonavir: Case Series.

Immunocompromised patients with B-cell deficiencies are at risk for prolonged symptomatic severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. We describe 4 patients treated for B-cell malignancies with B-cell-depleting therapies who developed persistent SARS-CoV-2 infection and had resolution of symptoms following an extended course of nirmatrelvir/ritonavir.

Early Antibiotic Discontinuation or De-escalation in High-Risk Patients With AML With Febrile Neutropenia and Prolonged Neutropenia.

BACKGROUND: There is minimal data evaluating the safety of antibiotic de-escalation in patients with acute myeloid leukemia (AML) with fever and ongoing neutropenia. Therefore, this study evaluated antibiotic prescribing, infection-related outcomes, and patient outcomes of an antibiotic de-escalation initiative. PATIENTS AND METHODS: This pre-post quasiexperimental study included adult patients with AML hospitalized with febrile neutropenia. An antibiotic de-escalation guideline was implemented in January 2017, which promoted de-escalation or discontinuation of intravenous antipseudomonal ß-lactams. The primary outcome assessment was the incidence of bacterial infection in a historical control group before guideline implementation compared with an intervention group after guideline implementation. RESULTS: A total of 93 patients were included. Antibiotic de-escalation occurred more frequently in the intervention group (71.7% vs 7.5%; P<.001), which resulted in fewer days of therapy for intravenous antipseudomonal ß-lactams (14 vs 25 days; P<.001). Thirty-day all-cause mortality and length of hospitalization were not different between groups. However, the intervention group had significantly fewer episodes of Clostridioides difficile colitis (5.7% vs 27.5%; P=.007). CONCLUSIONS: Implementation of an antibiotic de-escalation guideline resulted in decreased use of intravenous antipseudomonal ß-lactams and fewer episodes of C difficile colitis, without adversely impacting patient outcomes. Additional studies are needed, preferably in the form of randomized controlled trials, to confirm these results.

Acquired hypogammaglobulinemia and pathogen-specific antibody depletion after solid organ transplantation in human immunodeficiency virus infection: A brief report.

Hypogammaglobulinemia (HGG) frequently occurs in recipients after types of (SOT). The incidence and significance of HGG in HIV+ recipients of SOT are just being explored. We reported that 12% of the recipients in the SOT in multi-center HIV-TR (HIV-TR) Study developed moderate or severe HGG at 1 year. In LT recipients, this was associated with serious infections and death. We have now further characterized the decreased antibodies in HIV+ SOT recipients who developed HGG. We measured the levels of pathogen-specific antibodies and poly-specific self-reactive antibodies (PSA) in relation to total IgG levels from serial serum samples for 20 HIV+ SOT recipients who developed moderate to severe HGG following SOT. Serum antibody levels to measles, tetanus toxoid, and HIV-1 were determined by EIA. Levels of PSAs were determined by incubating control lymphocytes with patient serum, staining with anti-human IgG Fab-FITC, and analysis by flow cytometry. Levels of PSA were higher compared to healthy, HIV-uninfected controls at pre-transplant baseline and increased by weeks 12 and 26, but the changes were not significant. Likewise, anti-HIV antibody levels remained unchanged over time. In contrast, antibody levels against measles and tetanus were significantly reduced from baseline by week 12, and did not return to baseline, even after 2 years. For HIV patients who develop moderate to severe HGG after transplant, the reduction in IgG levels is associated with a significant decrease in pathogen-specific antibody titers, while PSA levels and anti-HIV antibodies are unchanged. This may contribute to infectious complications and other clinical endpoints.

A Randomized, Placebo-controlled Trial of Fidaxomicin for Prophylaxis of Clostridium difficile-associated Diarrhea in Adults Undergoing Hematopoietic Stem Cell Transplantation.

Background: Clostridium difficile-associated diarrhea (CDAD) is common during hematopoietic stem-cell transplantation (HSCT) and is associated with increased morbidity and mortality. We evaluated fidaxomicin for prevention of CDAD in HSCT patients. Methods: In this double-blind study, subjects undergoing HSCT with fluoroquinolone prophylaxis stratified by transplant type (autologous/allogeneic) were randomized to once-daily oral fidaxomicin (200 mg) or a matching placebo. Dosing began within 2 days of starting conditioning or fluoroquinolone prophylaxis and continued until 7 days after neutrophil engraftment or completion of fluoroquinolone prophylaxis/clinically-indicated antimicrobials for up to 40 days. The primary endpoint was CDAD incidence through 30 days after study medication. The primary endpoint analysis counted confirmed CDAD, receipt of CDAD-effective medications (for any indication), and missing CDAD assessment (for any reason, including death) as failures; this composite analysis is referred to as "prophylaxis failure" to distinguish from the pre-specified sensitivity analysis, which counted only confirmed CDAD (by toxin immunoassay or nucleic acid amplification test) as failure. Results: Of 611 subjects enrolled, 600 were treated and analyzed. Prophylaxis failure was similar in fidaxomicin and placebo recipients (28.6% vs 30.8%; difference 2.2% [-5.1, 9.5], P = .278). However, most failures were due to non-CDAD events. Confirmed CDAD was lower in fidaxomicin vs placebo recipients (4.3% vs 10.7%; difference 6.4% [2.2, 10.6], P = .0014). Drug-related adverse events occurred in 15.0% of fidaxomicin recipients and 20.0% of placebo recipients. Conclusions: While no difference was demonstrated between arms in the primary analysis, results of the sensitivity analysis demonstrated that fidaxomicin significantly reduced the incidence of CDAD in HSCT recipients. Clinical Trials Registration: NCT01691248.

Invasive Aspergillosis: Epidemiology, Clinical Aspects, and Treatment.

Invasive aspergillosis remains an often fatal, difficult-to treat infection in immunocompromised patients. Patients not classically defined as immunocompromised, especially those in an intensive care unit setting, also develop invasive aspergillosis. Clinical clues suggesting angioinvasion and radiographic modalities, especially computed tomographic scans, combined with newer non-culture-based diagnostic techniques, have allowed earlier recognition of invasive aspergillosis. Although mortality remains high, it has greatly decreased over the past 15 years. Voriconazole has supplanted amphotericin B, with its various toxicities, as primary treatment for invasive aspergillosis. Combination therapy with voriconazole and an echinocandin for initial therapy, based on results from a recent controlled clinical trial, could become the standard of care in high-risk patients.

Severe Influenza in 33 US Hospitals, 2013-2014: Complications and Risk Factors for Death in 507 Patients.

BACKGROUND: Influenza A (H1N1) pdm09 became the predominant circulating strain in the United States during the 2013-2014 influenza season. Little is known about the epidemiology of severe influenza during this season. METHODS: A retrospective cohort study of severely ill patients with influenza infection in intensive care units in 33 US hospitals from September 1, 2013, through April 1, 2014, was conducted to determine risk factors for mortality present on intensive care unit admission and to describe patient characteristics, spectrum of disease, management, and outcomes. RESULTS: A total of 444 adults and 63 children were admitted to an intensive care unit in a study hospital; 93 adults (20.9%) and 4 children (6.3%) died. By logistic regression analysis, the following factors were significantly associated with mortality among adult patients: older age (>65 years, odds ratio, 3.1 [95% CI, 1.4-6.9], P=.006 and 50-64 years, 2.5 [1.3-4.9], P=.007; reference age 18-49 years), male sex (1.9 [1.1-3.3], P=.031), history of malignant tumor with chemotherapy administered within the prior 6 months (12.1 [3.9-37.0], P<.001), and a higher Sequential Organ Failure Assessment score (for each increase by 1 in score, 1.3 [1.2-1.4], P<.001). CONCLUSION: Risk factors for death among US patients with severe influenza during the 2013-2014 season, when influenza A (H1N1) pdm09 was the predominant circulating strain type, shifted in the first postpandemic season in which it predominated toward those of a more typical epidemic influenza season.

Risk factors for piperacillin/tazobactam-resistant Gram-negative infection in hematology/oncology patients with febrile neutropenia.

PURPOSE: Febrile neutropenia (FN) is a life-threatening complication of cancer therapy, and initial ineffective therapy is associated with poor outcomes. Piperacillin/tazobactam (PTZ) is a commonly used empiric antibiotic for the treatment of FN, but resistance among Gram-negative pathogens is well described. We conducted a retrospective case-control study to identify risk factors for PTZ-resistant (PTZ-R) Gram-negative isolates. METHODS: Hematology/oncology patients with FN from November 2007 to November 2013 with a positive culture for Gram-negative bacilli were divided into two groups: PTZ-sensitive (PTZ-S) and PTZ-R. A multivariable model using logistic regression was constructed to identify risk factors for PTZ-R. RESULTS: A total of 171 patients were included (25 PTZ-R, 146 PTZ-S), yielding a 14.6 % resistance rate. Thirty-day all-cause mortality was significantly higher in the PTZ-R group (29 vs 11 %, P = 0.024). Multivariable analysis yielded intensive care unit (ICU) status (odds ratio (OR) 20.18; 95 % confidence interval (CI) 1.03-397.35; P = 0.048), antibiotics for > 14 days in the previous 90 days (OR 6.02; CI 1.17-30.93; P = 0.032), and respiratory source (OR 13.65; CI 1.14-163.57; P = 0.039) as significant risk factors for PTZ-R, and the receiver operating characteristic area under the curve of the model was 0.894. Among PTZ-R isolates, 88 % were sensitive to meropenem and 100 % were sensitive to amikacin. CONCLUSIONS: Given the high mortality rates in the PTZ-R group, a risk-factor-guided approach driven by this multivariable model may help identify patients that could benefit from amikacin combination therapy to help optimize empiric therapy in this setting.

Nocardia-induced granulocyte macrophage colony-stimulating factor is neutralized by autoantibodies in disseminated/extrapulmonary nocardiosis.

BACKGROUND: Nocardia species cause infections in both immunocompromised and otherwise immunocompetent patients, although the mechanisms defining susceptibility in the latter group are elusive. Anticytokine autoantibodies are an emerging cause of pathogen-specific susceptibility in previously healthy human immunodeficiency virus-uninfected adults, including anti-granulocyte macrophage colony-stimulating factor (GM-CSF) autoantibodies with cryptococcal meningitis. METHODS: Plasma from patients with disseminated/extrapulmonary nocardiosis and healthy controls was screened for anticytokine autoantibodies using a particle-based approach. Autoantibody function was assessed by intranuclear staining for GM-CSF-induced STAT5 phosphorylation in normal cells incubated with either patient or normal plasma. GM-CSF-mediated cellular activation by Nocardia was assessed by staining for intracellular cytokine production and intranuclear STAT5 phosphorylation. RESULTS: We identified neutralizing anti-GM-CSF autoantibodies in 5 of 7 patients studied with central nervous system nocardiosis and in no healthy controls (n = 14). GM-CSF production was induced by Nocardia in vitro, suggesting a causative role for anti-GM-CSF autoantibodies in Nocardia susceptibility and dissemination. CONCLUSIONS: In previously healthy adults with otherwise unexplained disseminated/extrapulmonary Nocardia infections, anti-GM-CSF autoantibodies should be considered. Their presence may suggest that these patients may be at risk for later development of pulmonary alveolar proteinosis or other opportunistic infections, and that patients may benefit from therapeutic GM-CSF administration.

Nephrogenic systemic fibrosis associated with stromal and vascular calcification, report of two cases.

Nephrogenic systemic fibrosis (NSF) is a systemic fibrosing disorder characterized by the development of large indurated plaques on the skin, primarily in patients with end-stage renal disease (ESRD). Skin biopsy reveals an increased frequency of CD34(+) and Factor XIIa+ cells. Microscopic calcification has been reported in the skin biopsies of rare cases of NSF. The etiology and significance of this calcification is not clear. We present two cases of typical NSF, for which marked stromal and vascular calcification was identified on skin biopsy. In both cases, the calcification was within typical NSF lesions and was intimately associated with aggregates of CD34(+), Factor XIIIa+ spindle and stellate cells. This particular pattern of calcification strongly argues against either nonspecific dystrophic calcification or coincidental metastatic calcification. These findings suggest that calcification may be intrinsic to the pathophysiology of NSF, at least in a subset of NSF patients. In addition, the vascular calcification involving small arteries and arterioles in these two cases morphologically resembled calciphylaxis, which is another poorly understood complication of ESRD. This resemblance raises the possibility that NSF may predispose to or develop in the vicinity of indolent lesions of early-stage calciphylaxis. We propose that skin biopsies performed as part of a diagnostic workup for suspected NSF should preferably include the deep dermis and subcutis, in order to assess possible vascular calcification.