Respiratory Complications in Children and Adolescents with Human Immunodeficiency Virus

Prevalence, clinical presentation and factors associated with chronic lung disease among children and adolescents living with HIV in Kenya

INTRODUCTION

Children and adolescents with HIV (CAHIV) may experience recurrent and severe respiratory disease and are at risk of residual lung sequelae, and long-term morbidity from chronically damaged lungs. With improved survival due to increased access to effective antiretroviral therapy there is an increasing population of CAHIV who require optimal life-long care. Chronic lung disease in CAHIV is an under-recognised problem in African settings. We sought to determine the prevalence, clinical presentation and factors associated with chronic lung disease (CLD) among CAHIV in Kenya.

METHODS

CAHIV aged ≤19 years in care at a public hospital in Nairobi were enrolled into a longitudinal cohort study. Sociodemographic and clinical information were obtained through interview, medical record review, physical examination and six-minute walk test. CD4 counts and viral load were determined. Enrolment data was analysed to determine baseline sociodemographic and clinical characteristics. Prevalence of CLD defined as presence of ≥2 respiratory symptoms or signs at enrolment was computed. Logistic regression analysis was performed to evaluate for association between various factors and presence or absence of CLD.

RESULTS

We enrolled 320 CAHIV of median age 13 (IQR 10-16) years, 80 (25%) were <10 years, 46% were female, 31% lived in a one-room house and 51% used polluting cooking fuel. Antiretroviral therapy (ART) was initiated after age five years in 56%, 43% had prior pneumonia or tuberculosis, 11% had low CD4 count and 79% were virologically suppressed. Common respiratory symptoms and signs were exertional breathlessness (40%), chronic cough (23%), chest problems in the preceding year (24%), tachypnoea (52%), finger clubbing (6%), exercise limitation (59%) and oxygen desaturation during exercise (7%). CLD was present in 82 (26%) participants, and adding the six-minute walk distance <70% of predicted (exercise limitation) identified an additional 28 (9%) CAHIV with CLD. CLD was more common among older teenagers (odds ratio (OR) 1.95), those who had prior TB or pneumonia (OR 2.04), delayed initiation of ART (OR 2.60), cotrimoxazole prophylaxis (OR 3.35) or TB preventive therapy (OR 2.81). CLD was associated with viraemia (OR 2.7), lower quality of life (OR 12.7), small houses (OR 2.05), caregiver having fewer years of education (OR 2.46), outdoor pollution exposure (OR 3.31) and lower use of polluting cooking fuel indoors (OR 0.26). Adjusted analysis revealed CLD to be associated with prior tuberculosis or pneumonia (adjusted OR (aOR) [95%CI] 2.15 [1.18-3.91]), small house (aOR 1.95 [1.02-3.73]), lower use of polluting cooking fuel (aOR 0.35 [0.13-0.94]) and negative impact on health-related quality of life (aOR 6.91 [3.66-13.03]).

CONCLUSIONS

CLD is highly prevalent across the age spectrum of CAHIV, and most are symptomatic with cough or exertional breathlessness. CLD is associated with prior tuberculosis or pneumonia, socio-environmental factors, and lower quality of life. Structured interventions are needed to provide optimal care specific to their needs.

HIV-associated lung disease

Lung disease encompasses acute, infectious processes and chronic, non-infectious processes such as chronic obstructive pulmonary disease, asthma and lung cancer. People living with HIV are at increased risk of both acute and chronic lung diseases. Although the use of effective antiretroviral therapy has diminished the burden of infectious lung disease, people living with HIV experience growing morbidity and mortality from chronic lung diseases. A key risk factor for HIV-associated lung disease is cigarette smoking, which is more prevalent in people living with HIV than in uninfected people. Other risk factors include older age, history of bacterial pneumonia, Pneumocystis pneumonia, pulmonary tuberculosis and immunosuppression. Mechanistic investigations support roles for aberrant innate and adaptive immunity, local and systemic inflammation, oxidative stress, altered lung and gut microbiota, and environmental exposures such as biomass fuel burning in the development of HIV-associated lung disease. Assessment, prevention and treatment strategies are largely extrapolated from data from HIV-uninfected people. Smoking cessation is essential. Data on the long-term consequences of HIV-associated lung disease are limited. Efforts to continue quantifying the effects of HIV infection on the lung, especially in low-income and middle-income countries, are essential to advance our knowledge and optimize respiratory care in people living with HIV.

Sputum bacterial load and bacterial composition correlate with lung function and are altered by long-term azithromycin treatment in children with HIV-associated chronic lung disease

BACKGROUND

Long-term azithromycin (AZM) treatment reduces the frequency of acute respiratory exacerbation in children and adolescents with HIV-associated chronic lung disease (HCLD). However, the impact of this treatment on the respiratory bacteriome is unknown.

METHOD

African children with HCLD (defined as forced expiratory volume in 1 s z-score (FEV1z) less than - 1.0 with no reversibility) were enrolled in a placebo-controlled trial of once-weekly AZM given for 48-weeks (BREATHE trial). Sputum samples were collected at baseline, 48 weeks (end of treatment) and 72 weeks (6 months post-intervention in participants who reached this timepoint before trial conclusion). Sputum bacterial load and bacteriome profiles were determined using 16S rRNA gene qPCR and V4 region amplicon sequencing, respectively. The primary outcomes were within-participant and within-arm (AZM vs placebo) changes in the sputum bacteriome measured across baseline, 48 weeks and 72 weeks. Associations between clinical or socio-demographic factors and bacteriome profiles were also assessed using linear regression.

RESULTS

In total, 347 participants (median age: 15.3 years, interquartile range [12.7-17.7]) were enrolled and randomised to AZM (173) or placebo (174). After 48 weeks, participants in the AZM arm had reduced sputum bacterial load vs placebo arm (16S rRNA copies/µl in log₁₀, mean difference and 95% confidence interval [CI] of AZM vs placebo - 0.54 [- 0.71; - 0.36]). Shannon alpha diversity remained stable in the AZM arm but declined in the placebo arm between baseline and 48 weeks (3.03 vs. 2.80, p = 0.04, Wilcoxon paired test). Bacterial community structure changed in the AZM arm at 48 weeks compared with baseline (PERMANOVA test p = 0.003) but resolved at 72 weeks. The relative abundances of genera previously associated with HCLD decreased in the AZM arm at 48 weeks compared with baseline, including Haemophilus (17.9% vs. 25.8%, p < 0.05, ANCOM ω = 32) and Moraxella (1% vs. 1.9%, p < 0.05, ANCOM ω = 47). This reduction was sustained at 72 weeks relative to baseline. Lung function (FEV1z) was negatively associated with bacterial load (coefficient, [CI]: - 0.09 [- 0.16; - 0.02]) and positively associated with Shannon diversity (0.19 [0.12; 0.27]). The relative abundance of Neisseria (coefficient, [standard error]: (2.85, [0.7], q = 0.01), and Haemophilus (- 6.1, [1.2], q < 0.001) were positively and negatively associated with FEV1z, respectively. An increase in the relative abundance of Streptococcus from baseline to 48 weeks was associated with improvement in FEV1z (3.2 [1.11], q = 0.01) whilst an increase in Moraxella was associated with decline in FEV1z (-2.74 [0.74], q = 0.002).

CONCLUSIONS

AZM treatment preserved sputum bacterial diversity and reduced the relative abundances of the HCLD-associated genera Haemophilus and Moraxella. These bacteriological effects were associated with improvement in lung function and may account for reduced respiratory exacerbations associated with AZM treatment of children with HCLD. Video Abstract.

Bronchiectasis in African children: Challenges and barriers to care

Bronchiectasis (BE) is a chronic condition affecting the bronchial tree. It is characterized by the dilatation of large and medium-sized airways, secondary to damage of the underlying bronchial wall structural elements and accompanied by the clinical picture of recurrent or persistent cough. Despite an increased awareness of childhood BE, there is still a paucity of data on the epidemiology, pathophysiological phenotypes, diagnosis, management, and outcomes in Africa where the prevalence is mostly unmeasured, and likely to be higher than high-income countries. Diagnostic pathways and management principles have largely been extrapolated from approaches in adults and children in high-income countries or from data in children with cystic fibrosis. Here we provide an overview of pediatric BE in Africa, highlighting risk factors, diagnostic and management challenges, need for a global approach to addressing key research gaps, and recommendations for practitioners working in Africa.