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.

Can procalcitonin help identify associated bacterial infection in patients with severe influenza pneumonia? A multicentre study.

PURPOSE: To determine whether procalcitonin (PCT) levels could help discriminate isolated viral from mixed (bacterial and viral) pneumonia in patients admitted to the intensive care unit (ICU) during the A/H1N1v2009 influenza pandemic. METHODS: A retrospective observational study was performed in 23 French ICUs during the 2009 H1N1 pandemic. Levels of PCT at admission were compared between patients with confirmed influenzae A pneumonia associated or not associated with a bacterial co-infection. RESULTS: Of 103 patients with confirmed A/H1N1 infection and not having received prior antibiotics, 48 (46.6%; 95% CI 37-56%) had a documented bacterial co-infection, mostly caused by Streptococcus pneumoniae (54%) or Staphylococcus aureus (31%). Fifty-two patients had PCT measured on admission, including 19 (37%) having bacterial co-infection. Median (range 25-75%) values of PCT were significantly higher in patients with bacterial co-infection: 29.5 (3.9-45.3) versus 0.5 (0.12-2) µg/l (P < 0.01). For a cut-off of 0.8 µg/l or more, the sensitivity and specificity of PCT for distinguishing isolated viral from mixed pneumonia were 91 and 68%, respectively. Alveolar condensation combined with a PCT level of 0.8 µg/l or more was strongly associated with bacterial co-infection (OR 12.9, 95% CI 3.2-51.5; P < 0.001). CONCLUSIONS: PCT may help discriminate viral from mixed pneumonia during the influenza season. Levels of PCT less than 0.8 µg/l combined with clinical judgment suggest that bacterial infection is unlikely.

[Severe H1N1 2009 influenza infection in adults: the French experience]. / Formes graves de la grippe H1N1 2009 chez l'adulte: l'expérience française.

The REVA-Flu-SRLF register allowed collection of data from 562 patients infected with H1N1 influenza virus 2009 and hospitalized in the intensive care unit (ICU). The overall mortality of these patients was 20%. The use of invasive ventilation, heart failure, and immunosuppression were associated with mortality. Three hundred forty-one (82%) among the 417 mechanically ventilated patients had an acute respiratory distress syndrome (ARDS). One hundred sixty-nine (30%) had a bacterial co-infection. Corticosteroid therapy was associated with an increased mortality in patients with ARDS. The occupancy rate associated with influenza patients crossed the threshold of 15% in many ICUs.