Solid organ transplantation: hypogammaglobulinaemia and infectious complications after solid organ transplantation

Clinical outcomes of immunoglobulin treatment for patients with secondary antibody deficiency: Data from the Ontario immunoglobulin treatment case registry

BACKGROUND

Despite the increasing number of cases of secondary antibody deficiency (SAD) and immunoglobulin (Ig) utilization, there is a paucity of data in the literature on clinical and patient-reported outcomes in this population.

OBJECTIVE

To describe immunoglobulin utilization patterns, clinical and patient-reported outcomes in patients with SAD on immunoglobulin replacement therapy (IgRT).

METHODS

A cross-sectional study of patients with secondary antibody deficiency enrolled in the Ontario Immunoglobulin Treatment (ONIT) Case Registry from June 2020 to September 2022 was completed. Demographics, comorbidities, indications for immunoglobulin treatment, clinical infections at baseline and post IgRT, and patient-reported outcomes were collected and analyzed.

RESULTS

There were 140 patients (58 males; 82 females; median age 68) with SAD during the study period; 131 were on subcutaneous Ig (SCIG) and 9 were on intravenous Ig (IVIG). The most common indication was chronic lymphocytic leukemia (CLL) (N = 52). IgRT reduced the average annual number of infections by 82.6%, emergency room (ER) visits by 84.6%, and hospitalizations by 83.3%. Overall, 84.6% of patients reported their health as better compared to before IgRT. Among those patients who switched from IVIG to SCIG (N = 35), 33.3% reported their health as the same, and 62.9% reported their health as better.

CONCLUSIONS

This study demonstrates that IgRT significantly improved clinical outcomes and patient-reported general health state in patients with SAD. This study also further supports the use of SCIG in patients with SAD.

Reduced risk of infections with the intravenous immunoglobulin, IgPro10, in patients at risk of secondary immunodeficiency-related infections

Aim: Patients with secondary immunodeficiency (SID) are at increased risk of infections and may be treated with immunoglobulin replacement therapy (IgRT). Despite growing efficacy evidence for IgRT in infection prevention in SID, treatment guidelines are not aligned. Materials & methods: A retrospective database analysis was conducted to assess treatment patterns and infection rates in patients at risk of SID-related infections, with or without IgRT (IgPro10) exposure, to evaluate real-world effectiveness of IgRT in infection prevention. Results: Of 11,448 patients included, 222 received IgPro10. B-cell malignancies and solid organ transplants were the predominant underlying conditions. Despite being sicker at baseline, the IgPro10 cohort demonstrated fewer infections post-index than the non-IgRT cohort. Conclusion: IgPro10 may be an effective option for infection prevention in SID.

ABO-Incompatible Kidney Transplantation: Low Rates of Infectious Complications and Excellent Patient Survival

BACKGROUND

A significant gap exists between demand and supply of organs for patients with end-stage renal disease. To increase the donor pool, kidney transplantation is performed across ABO- and HLA-incompatible barriers. ABO-incompatible kidney transplant (ABOi-KT) recipients are at increased risk of antibody-mediated rejection, infection, and mortality. Hypogammaglobulinemia secondary to immunosuppression is highly prevalent after solid organ transplantation, and intravenous immunoglobulin (IVIG) has been reported to reduce the risks of infections in various settings. We use high-dose IVIG in ABOi-KT recipients perioperatively. We aimed to determine the rate of infectious complications along with graft and patient survival in our ABOi-KT recipients.

METHODS

We included all adult patients who underwent ABOi-KT from the year 2007 to 2016. Patients received rituximab, plasma exchange, and IVIG (2 g/kg body weight). Thymoglobulin and intravenous methylprednisolone were used as induction treatment. Oral prednisone, mycophenolate mofetil, and tacrolimus were used as maintenance therapy.

RESULTS

A total of 77 ABOi-KTs were performed, and the recipients were followed up for a median of 1557 days. Two patients were diagnosed as having BK nephropathy. No patients were diagnosed as having pneumocystis infection, cytomegalovirus disease, herpes simplex, varicella zoster, or fungal infection. One-year graft and patient survival was 94.8% and 100%, respectively.

CONCLUSIONS

In our series of ABOi-KTs, we observed a low risk of infectious complications and excellent patient survival. High-dose IVIG might have reduced infections.

Infection in Kidney Transplant Recipients

In organ transplant recipients, impaired inflammatory responses suppress the clinical and radiologic findings of infection. The possible etiologies of infection are diverse, ranging from common bacterial and viral pathogens that affect the entire community to opportunistic pathogens that cause invasive disease only in immunocompromised hosts. Antimicrobial therapies required to treat established infection are often complex, with accompanying risks for drug toxicities and drug interactions with the immunosuppressive agents used to maintain graft function. Rapid and specific diagnosis is essential for successful therapy. The risk of serious infections in the organ transplant patient is largely determined by the interaction between two factors: the patient’s epidemiologic exposures and the patient’s net state of immunosuppression. The epidemiology of infection includes environmental exposures and nosocomial infections, organisms derived from donor tissues, and latent infections from the recipient activated with immunosuppression. The net state of immune suppression is a conceptual framework that measures those factors contributing to risk for infection: the dose, duration, and temporal sequence of immunosuppressive drugs; the presence of foreign bodies or injuries to mucocutaneous barriers; neutropenia; metabolic abnormalities including diabetes; devitalized tissues, hematomas, or effusions postsurgery; and infection with immunomodulating viruses. Multiple factors are present in each host. A timeline exists to aid in the development of a differential diagnosis for infection. The timeline for each patient is altered by changes in prophylaxis and immunosuppressive drugs. For common infections, new microbiologic assays, often nucleic acid based, are useful in the diagnosis and management of opportunistic infections.