Recurrent penicillin-resistant pneumococcal sepsis after matched unrelated donor (MUD) transplantation for refractory T cell lymphoma

A Description of the Type, Frequency and Severity of Infections Among Sixteen Patients Treated for T-Cell Lymphoma

Background

Infections are an important cause of morbidity and mortality in T-cell lymphomas. Factors contributing to increased risk of infection include the nature of the underlying disease, as well as treatment-associated immunosuppression. Currently there are few reports describing the types of infections, including preventable infections, in this cohort of patients. The aim of the study was to identify the type, frequency and severity of infection in patients with T-cell lymphoma undergoing treatment.

Methods

A case series was performed on all patients with T-cell lymphoma over a 5-year period from 2011 to 2016 at a tertiary Australian hospital. Information was collected from medical record review regarding patient demographics, lymphoma treatment and outcomes, and infectious outcomes. Severe infections were recorded, defined as infection requiring hospitalization.

Results

Sixteen patients were identified with a diagnosis of T-cell lymphoma who received treatment at our institution. There were 42 discrete episodes of severe infections in total. Severe infections occurred in 81% of patients, with over 40% having more than one infection. The median length of hospital stay was 13 days, 33% required intensive care admission and 14% of infectious episodes resulted in death. Only 50% of infectious episodes were microbiologically proven, with the most common etiology being bacterial. The most commonly isolated organism overall was Staphylococcus aureus, with the most common source of infection being skin and soft tissue. There was one case of cytomegalovirus (CMV) infection and five cases (12%) of invasive fungal infection. The highest rates of infection occurred during progressive disease. Rates of prophylaxis were highest with antiviral agents, and comparatively lower with antibacterial and antifungal agents.

Conclusion

Infections are frequent, opportunistic and severe in patients with T-cell lymphoma. Our data suggests that fungal prophylaxis may be indicated with T-cell lymphoma.

Incidence of invasive pneumococcal disease in immunocompromised patients: A systematic review and meta-analysis

BACKGROUND

Invasive pneumococcal disease (IPD) is associated with high morbidity and mortality, with immunocompromised patients (ICPs) at particular risk. Therefore, guidelines recommend pneumococcal vaccination for these patients. However, guidelines are scarcely underpinned with references to incidence studies of IPD in this population. This, potentially results in unawareness of the importance of vaccination and low vaccination rates. The objective of this systematic review and meta-analysis was to assess the incidence of IPD in ICPs.

METHODS

We systematically searched PubMed and Embase to identify studies in English published before December 6th, 2017 that included terms related to 'incidence', 'rate', 'pneumococcal', 'pneumoniae', 'meningitis', 'septicemia', or 'bacteremia'. We focused on patients with HIV, transplantation and chronic inflammatory diseases.

RESULTS

We included 45 studies in the systematic review reporting an incidence or rate of IPD, defined as isolation of Streptococcus pneumoniae from a normally sterile site. Random effects meta-analysis of 38 studies showed a pooled IPD incidence of 331/100,000 person years in patients with HIV in the late-antiretroviral treatment era in non-African countries, and 318/100,000 in African countries; 696 and 812/100,000 in patients who underwent an autologous or allogeneic stem cell transplantation, respectively; 465/100,000 in patients with a solid organ transplantation; and 65/100,000 in patients with chronic inflammatory diseases. In healthy control cohorts, the pooled incidence was 10/100,000.

DISCUSSION

ICPs are at increased risk of contracting IPD, especially those with HIV, and those who underwent transplantation. Based on our findings, we recommend pneumococcal vaccination in immunocompromised patients.

PROSPERO REGISTRATION

ID: CRD42016048438.

Infectious complications of acute and chronic GVHD

Immune defects prolonged by treatment regimens for graft-versus-host disease (GVHD) include cell-mediated immunity and hypogammaglobulinemia. Infections have become increasingly important during GVHD therapy, paradoxically because the success of immunosuppressive practice has led to improved survival. Infections originate from both endogenous and exogenous sources. Regimens for prevention of infection include: (a) continued surveillance monitoring for infections with reliable diagnostic testing, and (b) antimicrobial prophylaxis for those pathogens without markers that could be followed for surveillance. Repeated episodes of the same infection, diagnosis of a new life-threatening infection, or specific underlying hematologic diagnoses should prompt a look for gross immunoglobulin deficiency that could be corrected in the short term by immunoglobulin therapy. At times, measurement of CD4+ lymphocyte counts will assist in determining whether augmented prophylaxis is warranted. Since their efficacy may be limited, vaccine injections are not given during the immunosuppression associated with GVHD therapy, with the exception of influenza.

Invasive pneumococcal disease in adult hematopoietic stem cell transplant recipients: a decade of prospective population-based surveillance

Prospective population-based surveillance to assess the epidemiology of invasive pneumococcal disease (IPD) in hematopoietic stem cell transplant (HSCT) patients is limited and a comparison to the general population is lacking. By using a population-based Invasive Bacterial Diseases Network surveillance program, we studied the incidence, clinical significance, serotypes and antimicrobial resistance of IPD in a large cohort of adult HSCT patients and the general population. Streptococcus pneumoniae isolates and patient data were collected prospectively from 1995 to 2004. We identified 14 cases of IPD (based on sterile site isolates) in our HSCT population over a 10-year period. This translated to an incidence rate of 347 infections per 100 000 persons per year. This compared to an incidence of 11.5 per 100 000 persons per year in the general population (regression ratio=30.2; 95% confidence interval (CI) 17.8-50.8, P<0.00001). If nonsterile site isolates (respiratory tract) were included, the incidence rate in transplant patients was 446 per 100 000 persons per year. Serotypes 23F and 6B were most common; 100 and 69.2% of isolates were a serotype included in the pneumococcal polysaccharide and conjugate vaccines, respectively. The antimicrobial resistance rates were high, especially for trimethoprim/sulfamethoxazole. HSCT recipients are at significantly greater risk for IPD than the general population. Preventative strategies are necessary.

Efficacy of donor vaccination before hematopoietic cell transplantation and recipient vaccination both before and early after transplantation

Allogeneic hematopoietic cell transplantation is followed by humoral immunodeficiency. We evaluated whether antibody levels can be improved by recipient vaccination on day -1 and 50 and whether the levels can be further improved by donor vaccination on day -20. A total of 85 patients were randomized or assigned to one of the following strategies of immunization with Streptococcus pneumoniae polysaccharides, Haemophilus influenzae polysaccharide-protein conjugate, tetanus toxoid (protein recall antigen) and hepatitis B surface antigen (protein neo-antigen): (1) donor on day -20, recipient on days -1, +50 and +365 (D(-20)R(-1,50,365)); (2) donor nil, recipient on days -1, +50 and +365 (D(N)R(-1,50,365)); or (3) donor nil, recipient on day +365 (D(N)R(365)). For H. influenzae and tetanus, IgG levels after grafting were the highest in the D(-20)R(-1,50,365) patients, intermediate in the D(N)R(-1,50,365) patients and the lowest in the D(N)R(365) patients. For S. pneumoniae and hepatitis B, antibody levels appeared to be similar in all three patient groups. The results suggest that for polysaccharide-protein conjugate antigens or protein recall antigens, recipient immunization on days -1 and 50 improves antibody levels and that donor vaccination on day -20 further improves the levels. In contrast, neither recipient immunization on days -1 and 50 nor donor immunization on day -20 appears to be efficacious for polysaccharide antigens and poorly immunogenic protein neo-antigens.