Antibody-Mediated Rejection in Lung Transplantation: Clinical Outcomes and Donor-Specific Antibody Characteristics

In the context of lung transplant (LT), because of diagnostic difficulties, antibody-mediated rejection (AMR) remains a matter of debate. We retrospectively analyzed an LT cohort at Foch Hospital to demonstrate the impact of AMR on LT prognosis. AMR diagnosis requires association of clinical symptoms, donor-specific antibodies (DSAs), and C4d(+) staining and/or histological patterns consistent with AMR. Prospective categorization split patients into four groups: (i) DSA positive, AMR positive (DSA(pos) AMR(pos) ); (ii) DSA positive, AMR negative (DSA(pos) AMR(neg) ); (iii) DSA limited, AMR negative (DSA(Lim) ; equal to one specificity, with mean fluorescence intensity of 500-1000 once); and (iv) DSA negative, AMR negative (DSA(neg) ). AMR treatment consisted of a combination of plasmapheresis, intravenous immunoglobulin and rituximab. Among 206 transplanted patients, 10.7% were DSA(pos) AMR(pos) (n = 22), 40.3% were DSA(pos) AMR(neg) (n = 84), 6% were DSA(Lim) (n = 13) and 43% were DSA(neg) (n = 88). Analysis of acute cellular rejection at month 12 showed higher cumulative numbers (mean plus or minus standard deviation) in the DSA(pos) AMR(pos) group (2.1 ± 1.7) compared with DSA(pos) AMR(neg) (1 ± 1.2), DSA(Lim) (0.75 ± 1), and DSA(neg) (0.7 ± 1.23) groups. Multivariate analysis demonstrated AMR as a risk factor for chronic lung allograft dysfunction (hazard ratio [HR] 8.7) and graft loss (HR 7.56) for DSA(pos) AMR(pos) patients. Our results show a negative impact of AMR on LT clinical course and advocate for an early active diagnostic approach and evaluation of therapeutic strategies to improve prognosis.

Chronic active Epstein-Barr virus infection with cutaneous and sinus lymphoproliferation in a white female patient with 25 years' follow-up: an original case report

Chronic active Epstein-Barr virus infection (CAEBV) is characterized by chronic infectious mononucleosis-like symptoms associated with very high viral load, as assessed by quantitative polymerase chain reaction. We present an unusual case in a French woman who was followed up over 25 years with cutaneous and sinus lymphoproliferation. This white woman presented with a long history of recurrent cutaneous necrotic papules of the skin, which started during childhood and healed spontaneously with depressed scars. The lesions spread to the left maxillary sinus and were associated with hepatomegaly and splenomegaly with no other visceral locations. Pathological examination of the skin and sinus revealed a dermal monoclonal T-cell lymphoproliferative disorder, CD7(+) and CD20(-) , with no epidermotropism. T-cell receptor rearrangement was positive, showing the monoclonality from the first biopsy. This T-cell proliferation was positive for EBV-encoded small RNA and was associated with a high EBV viral load. Since then, the patient has been in good health, despite a permanently high EBV viral load. Hydroa vacciniforme (HV)-like lymphoma and natural killer/T-cell lymphoma were discussed, but none really fit our case. Natural killer cell lymphoma was ruled out because of the indolent course, but sinus lesions do not exist in HV-like lymphoma. A therapeutic approach is difficult because of the coexistence of viral infection and monoclonal T-cell proliferation. Chemotherapy is not efficient and induces immunosuppression, which may worsen the prognosis. Although rituximab may have an immunomodulatory function, it was not effective in our case.

HLA-G*01:04∼UTR3 Recipient Correlates With Lower Survival and Higher Frequency of Chronic Rejection After Lung Transplantation

Lung transplantation (LTx) is a valid therapeutic option for selected patients with end-stage lung disease. Soluble HLA-G (sHLA-G) has been associated with increased graft survival and decreased rejection episodes in solid organ transplantation. HLA-G haplotypes named UTRs, defined by SNPs from both the 5'URR and 3'UTR, have been reported to reliably predict sHLA-G level. The aim of this retrospective study was to determine the impact of HLA-G alleles and UTR polymorphism from LTx recipients on anti-HLA allo-immunization risk, overall survival and chronic rejection (CLAD). HLA-G SNPs were genotyped in 124 recipients who underwent LTx from 1996 to 2010 in Marseille, 123 healthy individuals and 26 cystic fibrosis patients not requiring LTx. sHLA-G levels were measured for 38 LTx patients at D0, M3 and M12 and for 123 healthy donors. HLA-G*01:06∼UTR2 was associated with a worse evolution of cystic fibrosis (p = 0.005) but not of long-term survival post-LTx. HLA-G*01:04∼UTR3 haplotype was associated with lower levels of sHLA-G at D0 and M3 (p = 0.03), impaired long-term survival (p = 0.001), increased CLAD occurrence (p = 0.03) and the production of de novo donor-specific antibodies (DSA) at M3 (p = 0.01). This study is the first to show the deleterious association of different HLA-G alleles and UTRs in LTx.

Next-Generation Sequencing for Diagnosis and Tailored Therapy: A Case Report of Astrovirus-Associated Progressive Encephalitis

A boy with X-linked agammaglobulinemia experienced progressive global motor decline, cerebellar syndrome, and epilepsy. All standard polymerase chain reactions for neurotropic viruses were negative on cerebrospinal fluid and brain biopsy. Next-generation sequencing allowed fast identification of a new astrovirus strain (HAstV-VA1/HMO-C-PA), which led to tailor the patient's treatment, with encouraging clinical monitoring over 1 year.

Value of allohaemagglutinins in the diagnosis of a polysaccharide antibody deficiency

Polysaccharide antibody deficiency is characterized by a poor or absent antibody response after vaccination with an unconjugated pneumococcal polysaccharide vaccine. Allohaemagglutinins (AHA) are antibodies to A or B polysaccharide antigens on the red blood cells, and are often used as an additional or alternative measure to assess the polysaccharide antibody response. However, few studies have been conducted to establish the clinical significance of AHA. To investigate the value of AHA to diagnose a polysaccharide antibody deficiency, pneumococcal polysaccharide antibody titres and AHA were studied retrospectively in 180 subjects in whom both tests had been performed. Receiver operating characteristic curves for AHA versus the pneumococcal vaccine response as a marker for the anti-polysaccharide immune response revealed an area under the curve between 0·5 and 0·573. Sensitivity and specificity of AHA to detect a polysaccharide antibody deficiency, as diagnosed by vaccination response, were low (calculated for cut-off 1/4-1/32). In subjects with only low pneumococcal antibody response, the prevalence of bronchiectasis was significantly higher than in subjects with only low AHA (45·5 and 1·3%, respectively) or normal pneumococcal antibody response and AHA (2·4%). A logistic regression model showed that low pneumococcal antibody response but not AHA was associated with bronchiectasis (odds ratio 46·2). The results of this study do not support the routine use of AHA to assess the polysaccharide antibody response in patients with suspected immunodeficiency, but more studies are warranted to clarify the subject further.

Conversion from clinically isolated syndrome to multiple sclerosis: A large multicentre study

Background and objective:

We explored which clinical and biochemical variables predict conversion from clinically isolated syndrome (CIS) to clinically definite multiple sclerosis (CDMS) in a large international cohort.

Methods:

Thirty-three centres provided serum samples from 1047 CIS cases with at least two years’ follow-up. Age, sex, clinical presentation, T2-hyperintense lesions, cerebrospinal fluid (CSF) oligoclonal bands (OCBs), CSF IgG index, CSF cell count, serum 25-hydroxyvitamin D3 (25-OH-D), cotinine and IgG titres against Epstein-Barr nuclear antigen 1 (EBNA-1) and cytomegalovirus were tested for association with risk of CDMS.

Results:

At median follow-up of 4.31 years, 623 CIS cases converted to CDMS. Predictors of conversion in multivariable analyses were OCB (HR = 2.18, 95% CI = 1.71–2.77, p < 0.001), number of T2 lesions (two to nine lesions vs 0/1 lesions: HR = 1.97, 95% CI = 1.52–2.55, p < 0.001; >9 lesions vs 0/1 lesions: HR = 2.74, 95% CI = 2.04–3.68, p < 0.001) and age at CIS (HR per year inversely increase = 0.98, 95% CI = 0.98–0.99, p < 0.001). Lower 25-OH-D levels were associated with CDMS in univariable analysis, but this was attenuated in the multivariable model. OCB positivity was associated with higher EBNA-1 IgG titres.

Conclusions:

We validated MRI lesion load, OCB and age at CIS as the strongest independent predictors of conversion to CDMS in this multicentre setting. A role for vitamin D is suggested but requires further investigation.

HIV infection en route to endogenization: two cases

The long-term spontaneous evolution of humans and the human immunodeficiency virus (HIV) is not well characterized; many vertebrate species, including humans, exhibit remnants of other retroviruses in their genomes that question such possible endogenization of HIV. We investigated two HIV-infected patients with no HIV-related disease and no detection with routine tests of plasma HIV RNA or cell-associated HIV DNA. We used Sanger and deep sequencing to retrieve HIV DNA sequences integrated in the human genome and tested the host humoral and cellular immune responses. We noticed that viruses from both patients were inactivated by the high prevalence of the transformation of tryptophan codons into stop codons (25% overall (3-100% per gene) and 24% overall (0-50% per gene)). In contrast, the humoral and/or cellular responses were strong for one patient and moderate for the other, indicating that a productive infection occurred at one stage of the infection. We speculate that the stimulation of APOBEC, the enzyme group that exchanges G for A in viral nucleic acids and is usually inhibited by the HIV protein Vif, has been amplified and made effective from the initial stage of the infection. Furthermore, we propose that a cure for HIV may occur through HIV endogenization in humans, as observed for many other retroviruses in mammals, rather than clearance of all traces of HIV from human cells, which defines viral eradication.

[Purulent pericarditis and colonic infiltrating to Salmonella enteritidis complicated by acute intussusception in a case of IL-12Rβ1 deficiency]

IL-12 receptor β1 deficiency (IL-12Rβ1) predisposes patients to mycobacteria and Salmonella infections. We report a case of IL-12Rβ1 deficiency with a fatal multi-resistant Salmonella enteritidis infection. This boy was born after from a consanguineous marriage, and diagnosed as having a IL-12Rβ1 deficiency since the age of 3 months. He presented with recurrent Salmonella enteritidis essentially digestive localization, complicated by purulent pericarditis at the same germ at the age of two and a half years. At the age of 3, a colonic infiltration due to a Salmonella enteritidis resistant to antibiotics, was complicated by acute intussusception, and the child died. The IL-12Rβ1 deficiency is considered as having a good prognosis, in contrast to what happened in our patient. We review therapeutic issues in these patients.

[Contraindications to lung transplantation: evolving limits?]

In France, the higher frequency of pulmonary sample in organ donors and the enhancement of surgical and perioperative life support techniques, have increased the number procedures and the short term prognosis of lung transplantation (LT). In this setting, the classical contraindications of LT need to be reconsidered. In this article, some of the classical contraindication of LT are confronted to the experience acquired in other solid organ transplantations or from some LT centers. Specific situations such as LT in patients with previous cancer, HIV infection, viral hepatitis, nutritional disorders, acutely ill LT candidates and aging candidates are addressed. Surgical contraindications are not reviewed.

[The management of lung transplantation candidates. A case series]

INTRODUCTION

Lung transplantation (LT) is associated with an increased risk of infection, cancer, chronic renal failure, cardiovascular disease and osteoporosis. Some risk factors precede transplantation and could benefit for early diagnosis and optimised care.

METHODS

The incidence of comorbidities and their treatment before referral were assessed in 157 consecutive lung transplant candidates between 2008 and 2011.

RESULTS

The median age was 37years [25; 51]. Fifty-six percent had a body mass index below 19kg/m(2). In the COPD group, only 50 % had undergone a pulmonary rehabilitation program in the preceding 2 years. Osteoporosis was present in 42 %, of whom 36 % were on bisphophonate therapy. Vitamin D deficiency was present in 65 %. Previously undiagnosed cardiovascular risk factors were discovered during LT assessment: hypertension in one patient, hypercholesterolemia in 6 % and diabetes in 4 %. Poor dental condition necessitating extractions were found in 41 % of patients. Protective anti-HBs antibodies levels were present in 50 % of the patients at the time of referral.

CONCLUSION

The assessment and early treatment of nutritional disorders, osteoporosis and risk factors for infection as well as addressing associated cardiovascular risk factors should be optimised in the care of patients with chronic respiratory insufficiency. The potential for becoming a lung transplant candidate in the future should be kept in mind early in the global management of those patients.

[Mendelian susceptibility to mycobacterial disease: a case report of disseminated infection due to Mycobacterium avium]

Mendelian susceptibility to mycobacterial disease (MSMD) is a rare genetic syndrome that predisposes patients to infections caused by weakly virulent mycobacterial species, such as bacillus Calmette-Guérin (BCG) vaccines and nontuberculous environmental mycobacteria in children free of classical immunodeficiencies. This syndrome consists of impaired antimycobacterial immunity (axis IL12/INF-γ) constituting a new immune deficiency and outlining its major role in mycobacterial immunity. We report a new case of MSMD through the observation of a young girl with a disseminated infection due to Mycobacterium avium. The molecular defect was 2 autosomal recessive mutations of the IL12Rβ1 gene (gene encoding for the β1 chain of the IL12 receptor) leading to the absence of the IL12 receptor on the activated T lymphocytes' surface. IL-12RB1 deficiency is the most common genetic etiology of MSMD. Today, there are 6 MSMD-causing genes, leading to 13 distinct genetic disorders. The clinical phenotype differs between patients. The description of the molecular and immunological basis of this syndrome has allowed us to explain the pathophysiology of antimycobacterial immunity and is essential to understanding and managing these diseases.

[When should immunologic explorations be carried out in children with suspicion of primary immunodeficiency?]

The identification of primary immunodeficiency is important in the prognosis and treatment of patients with these rare genetic diseases. For their diagnosis, simple screening explorations need to be carried out in case of severe, recurrent, and/or unusual infections. These include the whole blood cell count, plasmatic immunoglobulin levels, and postimmunization and/or post-infectious serologies. These examinations are used to guide the diagnosis with the joint analysis of patient's medical history, the clinical examination, and screening of biological results. They will then guide the prescription of more specific second-line explorations depending on the type of primary immunodeficiency suspected.

Mass transfer in a membrane aerated biofilm

We present experimental results of mass transfer of a non reactive tracer gas (neon) measured in aerobic heterotrophic biofilm developed from activated sludge. Biofilms are grown in various hydrodynamic conditions and the effective diffusivity is used to quantify the mass transfer through the biofilm. Beyond some cross-flow conditions, the effective diffusivity through the biofilm seems larger than in the bulk. This can be explained by a dispersion generated by convection inside the biofilm, as supported by an analytical flow model and in accordance to the numerical simulation proposed by Aspa et al. (2011).