Delayed and Attenuated Antibody Responses to Coronavirus Disease 2019 Vaccination With Poor Cross-Variant Neutralization in Solid-Organ Transplant Recipients-A Prospective Longitudinal Study

Background

Therapeutically immunosuppressed transplant recipients exhibit attenuated responses to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccines. To elucidate the kinetics and variant cross-protection of vaccine-induced antibodies in this population, we conducted a prospective longitudinal study in heart and lung transplant recipients receiving the SARS-CoV-2 messenger RNA (mRNA) 3-dose vaccination series.

Methods

We measured longitudinal serum antibody and neutralization responses against the ancestral and major variants of SARS-CoV-2 in SARS-CoV-2-uninfected lung (n = 18) and heart (n = 17) transplant recipients, non-lung-transplanted patients with cystic fibrosis (n = 7), and healthy controls (n = 12) before, during, and after the primary mRNA vaccination series.

Results

Among healthy controls, strong anti-spike responses arose immediately following vaccination and displayed cross-neutralization against all variants. In contrast, among transplant recipients, after the first 2 vaccine doses, increases in antibody concentrations occurred gradually, and cross-neutralization was completely absent against the Omicron B.1.1.529 variant. However, most (73%) of the transplant recipients had a significant response to the third vaccine dose, reaching levels comparable to those of healthy controls, with improved but attenuated neutralization of immune evasive variants, particularly Beta, Gamma, and Omicron. Responses in non-lung-transplanted patients with cystic fibrosis paralleled those in healthy controls.

Conclusions

In this prospective, longitudinal analysis of variant-specific antibody responses, lung and heart transplant recipients display delayed and defective responses to the first 2 SARS-CoV-2 vaccine doses but significantly augmented responses to a third dose. Gaps in antibody-mediated immunity among transplant recipients are compounded by decreased neutralization against Omicron variants, leaving many patients with substantially weakened immunity against currently circulating variants.

Hidden in plain sight: urinary Cryptococcus neoformans missed by routine diagnostics in a patient with acute leukemia

Cryptococcuria is a rare manifestation of localized cryptococcal disease. We present a case of Cryptococcus neoformans urinary tract infection in an immunocompromised host missed by routine laboratory workup. The patient had negative blood cultures, a negative serum cryptococcal antigen (CrAg), and “non-Candida yeast” growing in urine culture that was initially dismissed as non-pathogenic. The diagnosis was ultimately made by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) from a repeat urine culture after transfer to a tertiary care center. Cryptococcus should be considered in the differential of refractory urinary tract infections growing non-Candida yeast.

Invasive Fungal Infections and Targeted Therapies in Hematological Malignancies

The use of targeted biologic therapies for hematological malignancies has greatly expanded in recent years. These agents act upon specific molecular pathways in order to target malignant cells but frequently have broader effects involving both innate and adaptive immunity. Patients with hematological malignancies have unique risk factors for infection, including immune dysregulation related to their underlying disease and sequelae of prior treatment regimens. Determining the individual risk of infection related to any novel agent is challenging in this setting. Invasive fungal infections (IFIs) represent one of the most morbid infectious complications observed in hematological malignancy. In recent years, growing evidence suggests that certain small molecule inhibitors, such as BTK inhibitors and PI3K inhibitors, may cause an increased risk of IFI in certain patients. It is imperative to better understand the impact that novel targeted therapies might have on the development of IFIs in this high-risk patient population.

Vaccine serologic responses among transplant patients associate with COVID-19 infection and T peripheral helper cells

Background

Therapeutically immunosuppressed transplant recipients exhibit attenuated responses to COVID-19 vaccines. To better understand the immune alterations that determined poor vaccine response, we correlated quantities of circulating T and B cell subsets at baseline with longitudinal serologic responses to SARS-CoV-2 mRNA vaccination in heart and lung transplant recipients.

Methods

Samples at baseline and at approximately 8 and 30 days after each vaccine dose for 22 heart and lung transplant recipients with no history of COVID-19, four heart and lung transplant recipients with prior COVID-19 infection, and 12 healthy controls undergoing vaccination were analyzed. Anti-spike protein receptor binding domain (RBD) IgG and pseudovirus neutralization activity were measured. Proportions of B and T cell subsets at baseline were comprehensively quantitated.

Results

At 8-30 days post vaccination, healthy controls displayed robust anti-RBD IgG responses, whereas heart and lung transplant recipients showed minimally increased responses. A parallel absence of activity was observed in pseudovirus neutralization. In contrast, three of four (75%) transplant recipients with prior COVID-19 infection displayed robust responses at levels comparable to controls. Baseline levels of activated PD-1 ⁺ HLA-DR ⁺ CXCR5 ^- CD4 ⁺ T cells (also known as T peripheral helper [T _PH ] cells) and CD4+ T cells strongly predicted the ability to mount a response.

Conclusions

Immunosuppressed patients have defective vaccine responses but can be induced to generate neutralizing antibodies after SARS-CoV-2 infection. Strong correlations of vaccine responsiveness with baseline T _PH and CD4 ⁺ T cell numbers highlights a role for T helper activity in B cell differentiation into antibody secreting cells during vaccine response.

Validation of pneumonia prognostic scores in a statewide cohort of hospitalised patients with COVID-19

OBJECTIVE

We aimed to externally validate the predictive performance of two recently developed COVID-19-specific prognostic tools, the COVID-GRAM and CALL scores, and prior prognostic scores for community-acquired pneumonia (CURB-65), viral pneumonia (MuBLSTA) and H1N1 influenza pneumonia (Influenza risk score) in a contemporary US cohort.

METHODS

We included 257 hospitalised patients with laboratory-confirmed COVID-19 pneumonia from three teaching hospitals in Rhode Island. We extracted data from within the first 24 hours of admission. Variables were excluded if values were missing in >20% of cases, otherwise, missing values were imputed. One hundred and fifteen patients with complete data after imputation were used for the primary analysis. Sensitivity analysis was performed after the exclusion of one variable (LDH) in the complete dataset (n = 257). Primary and secondary outcomes were in-hospital mortality and critical illness (mechanical ventilation or death), respectively.

RESULTS

Only the areas under the receiver-operating characteristic curves (RO-AUC) of COVID-GRAM (RO-AUC = 0.775, 95% CI 0.525-0.915) for in-hospital death, and CURB65 for in-hospital death (RO-AUC = 0.842, 95% CI 0.674-0.932) or critical illness (RO-AUC = 0.766, 95% CI 0.584-0.884) were significantly better than random. Sensitivity analysis yielded similar trends. Calibration plots showed better agreement between the estimated and observed probability of in-hospital death for CURB65, compared with COVID-GRAM. The negative predictive value (NPV) of CURB65 ≥2 was 97.2% for in-hospital death and 88.1% for critical illness.

CONCLUSIONS

The COVID-GRAM score demonstrated acceptable predictive performance for in-hospital death. The CURB65 score had better prognostic utility for in-hospital death and critical illness. The high NPV of CURB65 values ≥2 may be useful in triaging and allocation of resources.

Posterior reversible encephalopathy syndrome in a patient with HIV/AIDS and immune reconstitution syndrome: a case study and literature review

The etiology of posterior reversible encephalopathy (PRES) is typically multifactorial. Patients with HIV are at risk for the development of this syndrome. We review 17 published cases of HIV and PRES and describe the second reported case of PRES in the setting of HIV and immune reconstitution syndrome (IRIS). IRIS has not yet been described as a risk factor for PRES.