Distinct lung microbiota associate with HIV-associated chronic lung disease in children.

Chronic lung disease (CLD) is a common co-morbidity for HIV-positive children and adolescents on antiretroviral therapy (ART) in sub-Saharan Africa. In this population, distinct airway microbiota may differentially confer risk of CLD. In a cross-sectional study of 202 HIV-infected children aged 6-16 years in Harare, Zimbabwe, we determined the association of sputum microbiota composition (using 16S ribosomal RNA V4 gene region sequencing) with CLD defined using clinical, spirometric, or radiographic criteria. Forty-two percent of children were determined to have CLD according to our definition. Dirichlet multinomial mixtures identified four compositionally distinct sputum microbiota structures. Patients whose sputum microbiota was dominated by Haemophilus, Moraxella or Neisseria (HMN) were at 1.5 times higher risk of CLD than those with Streptococcus or Prevotella (SP)-dominated microbiota (RR = 1.48, p = 0.035). Cell-free products of HMN sputum microbiota induced features of epithelial disruption and inflammatory gene expression in vitro, indicating enhanced pathogenic potential of these CLD-associated microbiota. Thus, HIV-positive children harbor distinct sputum microbiota, with those dominated by Haemophilus, Moraxella or Neisseria associated with enhanced pathogenesis in vitro and clinical CLD.

Obese patients with idiopathic pulmonary fibrosis have a higher 90-day mortality risk with bilateral lung transplantation.

BACKGROUND: Obese patients with idiopathic pulmonary fibrosis (IPF) have higher 90-day mortality after lung transplantation. We sought to determine whether body mass index (BMI) differentially modified the effect of transplant procedure type on 90-day mortality in IPF patients. METHODS: We analyzed data from the Organ Procurement and Transplantation Network (OPTN) for all patients with IPF who were transplanted between 2000 and 2010. Post-transplant survival was examined using Kaplan-Meier estimates. Multivariable logistic regression modeling was used to determine the difference in 90-day survival. The primary variable of interest was the interaction term between body mass index (BMI) and transplant type. RESULTS: A total of 3,389 (58% single-lung transplant [SLT] and 42% bilateral lung transplant [BLT]) subjects were included. Multivariable logistic regression modeling demonstrated a statistically significant interaction between BMI and transplant type (p = 0.047). Patients with a BMI > 30 kg/m(2) who received a BLT are 1.71 times (95% CI [1.03 to 2.85], p = 0.038) more likely to die within 90 days than BLT recipients with a BMI of 18.5 to 30 kg/m(2). CONCLUSIONS: Our results suggest that obese patients who receive a BLT may be at higher risk of 90-day mortality compared with patients of normal weight. Further study is needed to obtain more detailed information about comorbidities and other risk factors for early death that are not included in the OPTN database.