Chronic lung disease in human immunodeficiency virus (HIV) infected children

Surgery for bronchiectasis in children living with HIV: A case series from a low- to middle-income country

Background

Bronchiectasis (BE) in children living with HIV (CLWH) remains a significant cause of morbidity and mortality, especially in tuberculosis (TB)-endemic low- and middle-income countries. Treatment modalities for BE in CLWH currently focus mainly on prevention of infections and management of symptoms, while surgical management is indicated for a select group. In contrast, surgical management in non-cystic fibrosis BE is well established.

Objectives

To describe the indications for and complications of surgical resection for BE in CLWH, and to identify variables influencing outcome.

Methods

A retrospective medical records review was conducted of all CLWH aged ≤14 years who underwent surgical resection for BE at Tygerberg Hospital, Cape Town, South Africa, between 1 January 2007 and 30 September 2014. The variables collected included immune status, antiretroviral treatment (ART), previous treatment for TB, operative and postoperative complications, and postoperative symptom relief.

Results

Twelve CLWH on ART with symptomatic BE underwent surgical resection. The mean age was 7 years and the mean CD4 count 970 cells/µL. Indications for surgery included recurrent infections, chronic cough and persistent lobar collapse. The most common procedures were left lower lobe lobectomy (42%), left pneumonectomy (17%) and right bilobectomy (17%). Complications were limited to persistent pneumothorax after surgery in one child. There were no deaths. Ten children (83%) showed significant improvement of symptoms at follow-up.

Conclusion

Surgical resection for BE in CLWH can be performed safely with a low complication rate, resulting in significant improvement of symptoms postoperatively.

Study synopsis

What the study adds. Bronchiectasis (BE) in children living with HIV (CLWH) is a significant cause of morbidity and mortality. Current treatment focuses on preventing infections and managing symptoms, while surgical management is rarely considered. A retrospective medical records review of 12 children aged ≤14 years in South Africa found that surgical resection for BE can be performed with a low complication rate, resulting in significant improvement of symptoms postoperatively. Variables influencing outcome include immune status, antiretroviral treatment and previous treatment for tuberculosis.Implications of the findings. This study demonstrates that surgery for BE can be performed safely in CLWH, with significant improvement of respiratory symptoms postoperatively.

Secondary Immunodeficiency and Non-cystic Fibrosis Bronchiectasis

Bronchiectasis is a chronic respiratory disease characterized by abnormal dilation of the bronchi that causes cough, sputum, and recurrent infections. As it may be associated with various respiratory or systemic diseases, a critical aspect of managing bronchiectasis is to identify the underlying cause. Immunodeficiency is a rare but important cause of bronchiectasis, and its treatability is a significant trait for bronchiectasis management. While primary immunodeficiencies in bronchiectasis are well recognized, secondary immunodeficiencies remain under-reported and under-researched. Secondary immunodeficiencies may result from various diseases and conditions, such as hematologic malignancies, human immunodeficiency virus infection, renal transplantation, or the use of immunosuppressive drugs, and may contribute to the occurrence of bronchiectasis. Recurrent pulmonary and/or extrapulmonary infections in bronchiectasis may indicate the presence of secondary immunodeficiency in patients with these underlying conditions. For treatment, examining the underlying condition, managing bronchiectasis adequately, and prophylactic antibiotics (e.g., macrolide) and/or supplementary immunoglobulin G therapy may provide potential benefits. Considering the projected increase in the prevalence of secondary immunodeficiencies and bronchiectasis, future guidelines and research on the diagnosis and optimized treatment are needed.

Characterization of bacterial and viral pathogens in the respiratory tract of children with HIV-associated chronic lung disease: a case-control study

INTRODUCTION

Chronic lung disease is a major cause of morbidity in African children with HIV infection; however, the microbial determinants of HIV-associated chronic lung disease (HCLD) remain poorly understood. We conducted a case-control study to investigate the prevalence and densities of respiratory microbes among pneumococcal conjugate vaccine (PCV)-naive children with (HCLD +) and without HCLD (HCLD-) established on antiretroviral treatment (ART).

METHODS

Nasopharyngeal swabs collected from HCLD + (defined as forced-expiratory-volume/second < -1.0 without reversibility postbronchodilation) and age-, site-, and duration-of-ART-matched HCLD- participants aged between 6-19 years enrolled in Zimbabwe and Malawi (BREATHE trial-NCT02426112) were tested for 94 pneumococcal serotypes together with twelve bacteria, including Streptococcus pneumoniae (SP), Staphylococcus aureus (SA), Haemophilus influenzae (HI), Moraxella catarrhalis (MC), and eight viruses, including human rhinovirus (HRV), respiratory syncytial virus A or B, and human metapneumovirus, using nanofluidic qPCR (Standard BioTools formerly known as Fluidigm). Fisher's exact test and logistic regression analysis were used for between-group comparisons and risk factors associated with common respiratory microbes, respectively.

RESULTS

A total of 345 participants (287 HCLD + , 58 HCLD-; median age, 15.5 years [IQR = 12.8-18], females, 52%) were included in the final analysis. The prevalence of SP (40%[116/287] vs. 21%[12/58], p = 0.005) and HRV (7%[21/287] vs. 0%[0/58], p = 0.032) were higher in HCLD + participants compared to HCLD- participants. Of the participants positive for SP (116 HCLD + & 12 HCLD-), 66% [85/128] had non-PCV-13 serotypes detected. Overall, PCV-13 serotypes (4, 19A, 19F: 16% [7/43] each) and NVT 13 and 21 (9% [8/85] each) predominated. The densities of HI (2 × 104 genomic equivalents [GE/ml] vs. 3 × 102 GE/ml, p = 0.006) and MC (1 × 104 GE/ml vs. 1 × 103 GE/ml, p = 0.031) were higher in HCLD + compared to HCLD-. Bacterial codetection (≥ any 2 bacteria) was higher in the HCLD + group (36% [114/287] vs. (19% [11/58]), (p = 0.014), with SP and HI codetection (HCLD + : 30% [86/287] vs. HCLD-: 12% [7/58], p = 0.005) predominating. Viruses (predominantly HRV) were detected only in HCLD + participants. Lastly, participants with a history of previous tuberculosis treatment were more likely to carry SP (adjusted odds ratio (aOR): 1.9 [1.1 -3.2], p = 0.021) or HI (aOR: 2.0 [1.2 - 3.3], p = 0.011), while those who used ART for ≥ 2 years were less likely to carry HI (aOR: 0.3 [0.1 - 0.8], p = 0.005) and MC (aOR: 0.4 [0.1 - 0.9], p = 0.039).

CONCLUSION

Children with HCLD + were more likely to be colonized by SP and HRV and had higher HI and MC bacterial loads in their nasopharynx. The role of SP, HI, and HRV in the pathogenesis of CLD, including how they influence the risk of acute exacerbations, should be studied further.

TRIAL REGISTRATION

The BREATHE trial (ClinicalTrials.gov Identifier: NCT02426112 , registered date: 24 April 2015).

Adults with Perinatally Acquired HIV; Emerging Clinical Outcomes and Data Gaps

In resourced settings, adults living with perinatally acquired HIV are approaching the 5th decade of life. Their clinical and psychological outcomes highlight potential future issues for the much larger number of adolescents growing up with HIV in sub-Saharan Africa, and will inform the development of appropriate healthcare services. Lifelong exposure to HIV, and increasingly to antiretroviral therapy throughout growth and development, contrasts with adults acquiring HIV in later life. This review describes the clinical outcomes for adults living with perinatally acquired HIV including post transition mortality, morbidity and retention in care. Rates of viral suppression, drug resistance and immunological function are explored. Co-morbidities focus on metabolic, cardiovascular, respiratory and bone health with quality-of-life data including neurocognitive functioning and mental health. Sexual and reproductive health including vaccine-preventable disease and the prevention of onward transmission to partners and infants are considered. The data gaps and future research questions to optimise outcomes for this emerging adult cohort are highlighted.

Pulmonary Function in HIV-Infected Children at a Tertiary Care Hospital in North India: A Prospective Cross-Sectional Study

Background The global burden of HIV remains significant, particularly in India. Antiretroviral therapy (ART) has improved outcomes for children with HIV, yet understanding the virus's impact on respiratory health is essential. Pulmonary complications, common in HIV-infected adults, are poorly understood in children. Despite India's high HIV prevalence, data on pediatric lung function are lacking. This study aims to evaluate spirometry-based pulmonary function in perinatally HIV-infected children, exploring associations with disease severity, immune status, and other factors. Methods This prospective cross-sectional study conducted in a North Indian tertiary care hospital aimed to assess pulmonary function using spirometry in children (6-18 years) with HIV infection. Ethical approval and informed consent were secured. Data on demographics, clinical history, CD4+ T-cell counts, and viral load were collected. Certified respiratory therapists performed spirometry using standardized protocols. Descriptive statistics were computed, and differences in pulmonary function based on CD4+ T-cell counts, viral load, and opportunistic infection were analyzed. The study adhered to ethical guidelines and maintained participants' confidentiality. Results This cross-sectional study enrolled 57 children (mean age 13.6±3.2 years) with HIV infection. Age distribution was <9 years (24.6%), 9-11 years (28.1%), and >11 years (47.4%). Males constituted 56.1%. The mean BMI was 15.92±2.78 kg/m². HIV viral load (87.23±56.28 copies/μL) and CD4 count (1146.32±103.98 cells/mm³) were recorded. ART duration averaged 6.21±1.36 years. Viral load groups were <1 (52.6%), 1-1000 (26.3%), and >1000 copies/μL (21.1%). CD4 categories were >500 cells/mm³ (47.4%), 200-499 (42.1%), and <200 cells/mm³ (10.5%). Spirometry showed 71.9% normal and 28.1% abnormal (mild/moderate obstruction: 18.8%, mild/moderate restriction: 81.3%). No significant spirometric differences were observed among CD4 or viral load groups (p>0.05), nor with opportunistic infections (p>0.05). Conclusion This study reveals complex associations between spirometric parameters and CD4 count, viral load, and opportunistic infections in children with HIV. Further research, including longitudinal studies, is needed to unravel the intricate interplay and improve management strategies for this population.

Tuberculosis revisted: classic imaging findings in childhood

Tuberculosis (TB) remains one of the major public health threats worldwide, despite improved diagnostic and therapeutic methods. Tuberculosis is one of the main causes of infectious disease in the chest and is associated with substantial morbidity and mortality in paediatric populations, particularly in low- and middle-income countries. Due to the difficulty in obtaining microbiological confirmation of pulmonary TB in children, diagnosis often relies on a combination of clinical and radiological findings. The early diagnosis of central nervous system TB is challenging with presumptive diagnosis heavily reliant on imaging. Brain infection can present as a diffuse exudative basal leptomeningitis or as localised disease (tuberculoma, abscess, cerebritis). Spinal TB may present as radiculomyelitis, spinal tuberculoma or abscess or epidural phlegmon. Musculoskeletal manifestation accounts for 10% of extrapulmonary presentations but is easily overlooked with its insidious clinical course and non-specific imaging findings. Common musculoskeletal manifestations of TB include spondylitis, arthritis and osteomyelitis, while tenosynovitis and bursitis are less common. Abdominal TB presents with a triad of pain, fever and weight loss. Abdominal TB may occur in various forms, as tuberculous lymphadenopathy or peritoneal, gastrointestinal or visceral TB. Chest radiographs should be performed, as approximately 15% to 25% of children with abdominal TB have concomitant pulmonary infection. Urogenital TB is rare in children. This article will review the classic radiological findings in childhood TB in each of the major systems in order of clinical prevalence, namely chest, central nervous system, spine, musculoskeletal, abdomen and genitourinary system.

Severe Recurrent Bacterial Pneumonia Among Children Living With HIV

BACKGROUND

Bacterial pneumonia imparts a major morbidity and mortality burden on children living with HIV, yet effective prevention and treatment options are underutilized. We explored clinical factors associated with severe recurrent bacterial pneumonia among children living with HIV.

METHODS

Children enrolled in the TREAT Asia Pediatric HIV Observational Database were included if they started antiretroviral therapy (ART) on or after January 1st, 2008. Factors associated with severe recurrent bacterial pneumonia were assessed using competing-risk regression.

RESULTS

A total of 3,944 children were included in the analysis; 136 cases of severe recurrent bacterial pneumonia were reported at a rate of 6.5 [95% confidence interval (CI): 5.5-7.7] events per 1,000 patient-years. Clinical factors associated with severe recurrent bacterial pneumonia were younger age [adjusted subdistribution hazard ratio (aHR): 4.4 for <5 years versus ≥10 years, 95% CI: 2.2-8.4, P < 0.001], lower weight-for-age z-score (aHR: 1.5 for <-3.0 versus >-2.0, 95% CI: 1.1-2.3, P = 0.024), pre-ART diagnosis of severe recurrent bacterial pneumonia (aHR: 4.0 versus no pre-ART diagnosis, 95% CI: 2.7-5.8, P < 0.001), past diagnosis of symptomatic lymphoid interstitial pneumonitis or chronic HIV-associated lung disease, including bronchiectasis (aHR: 4.8 versus no past diagnosis, 95% CI: 2.8-8.4, P < 0.001), low CD4% (aHR: 3.5 for <10% versus ≥25%, 95% CI: 1.9-6.4, P < 0.001) and detectable HIV viral load (aHR: 2.6 versus undetectable, 95% CI: 1.2-5.9, P = 0.018).

CONCLUSIONS

Children <10-years-old and those with low weight-for-age, a history of respiratory illness, low CD4% or poorly controlled HIV are likely to gain the greatest benefit from targeted prevention and treatment programs to reduce the burden of bacterial pneumonia in children living with HIV.

Pediatric pulmonology 2020 year in review: Rare and diffuse lung disease

Pediatric Pulmonology publishes original research, review articles, and case reports on topics related to a wide range of children's respiratory disorders. Here we review some of the most notable manuscripts published in 2020 in this journal on (1) children's interstitial lung disease (chILD), (2) congenital airway and lung anomalies, and (3) primary ciliary dyskinesia and other non-cystic fibrosis bronchiectasis. The articles reviewed are discussed in context with published works from other journals.

Immunopathogenesis in HIV-associated pediatric tuberculosis

Tuberculosis (TB) is an increasing global emergency in human immunodeficiency virus/acquired immune deficiency syndrome (HIV/AIDS) patients, in which host immunity is dysregulated and compromised. However, the pathogenesis and efficacy of therapeutic strategies in HIV-associated TB in developing infants are essentially lacking. Bacillus Calmette-Guerin vaccine, an attenuated live strain of Mycobacterium bovis, is not adequately effective, which confers partial protection against Mycobacterium tuberculosis (Mtb) in infants when administered at birth. However, pediatric HIV infection is most devastating in the disease progression of TB. It remains challenging whether early antiretroviral therapy (ART) could maintain immune development and function, and restore Mtb-specific immune function in HIV-associated TB in children. A better understanding of the immunopathogenesis in HIV-associated pediatric Mtb infection is essential to provide more effective interventions, reducing the risk of morbidity and mortality in HIV-associated Mtb infection in infants. IMPACT: Children living with HIV are more likely prone to opportunistic infection, predisposing high risk of TB diseases. HIV and Mtb coinfection in infants may synergistically accelerate disease progression. Early ART may probably induce immune reconstitution inflammatory syndrome and TB pathology in HIV/Mtb coinfected infants.

Pediatric Lower Respiratory Tract Infections: Imaging Guidelines and Recommendations

Lower respiratory tract infection (LRTI) remains a major cause of morbidity and mortality in children. Various organisms cause LRTI, including viruses, bacteria, fungi, and parasites, among others. Infections caused by 2 or more organisms also occur, sometimes enhancing the severity of the infection. Medical imaging helps confirm a diagnosis but also plays a role in the evaluation of acute and chronic sequelae. Medical imaging tests help evaluate underlying pathology in pediatric patients with recurrent or long-standing symptoms as well as the immunocompromised.

Granulomatous Lymphocytic Interstitial Lung Disease in a Spectrum of Pediatric Primary Immunodeficiencies

BACKGROUND

Granulomatous lymphocytic interstitial lung disease (GLILD) has been increasingly recognized in children affected with primary immunodeficiencies (PIDs). In this study, we aimed to better characterize the spectrum of pediatric PIDs coexisting with GLILD including clinical and immunological predictors, thoracic imaging findings, and histopathologic features.

METHODS

We respectively reviewed records of six representative cases of children, three of them affected with common variable immunodeficiency (CVID) and three with syndromic immunodeficiencies, in whom a diagnosis of GLILD was established based on clinical, radiological, and histopathologic findings. Clinical and immunological predictors for GLILD were also analyzed in the patients studied.

RESULTS

All the children with GLILD had a history of autoimmune phenomena, organ-specific immunopathology, and immune dysregulation. Defective B-cell maturation and deficiency of memory B cells were found in all the children with GLILD. The radiological and histopathological features consistent with the diagnosis of GLILD, granulomatous disease, and lymphoid hyperplasia, were accompanied by chronic airway disease with bronchiectasis in children with CVID and syndromic PIDs.

CONCLUSIONS

Our study shows that both CVID and syndromic PIDs may be complicated with GLILD. Further studies are required to understand the predictive value of coexisting autoimmunity and immune dysregulation in the recognition of GLILD in children with PIDs.

Prevalence and antimicrobial resistance profiles of respiratory microbial flora in African children with HIV-associated chronic lung disease

BACKGROUND

HIV-associated chronic lung disease (CLD) is common among children living with HIV (CLWH) in sub-Saharan Africa, including those on antiretroviral therapy (ART). However, the pathogenesis of CLD and its possible association with microbial determinants remain poorly understood. We investigated the prevalence, and antibiotic susceptibility of Streptococcus pneumoniae (SP), Staphylococcus aureus (SA), Haemophilus influenzae (HI), and Moraxella catarrhalis (MC) among CLWH (established on ART) who had CLD (CLD+), or not (CLD-) in Zimbabwe and Malawi.

METHODS

Nasopharyngeal swabs (NP) and sputa were collected from CLD+ CLWH (defined as forced-expiratory volume per second z-score < - 1 without reversibility post-bronchodilation with salbutamol), at enrolment as part of a randomised, placebo-controlled trial of azithromycin (BREATHE trial - NCT02426112 ), and from age- and sex-matched CLD- CLWH. Samples were cultured, and antibiotic susceptibility testing was conducted using disk diffusion. Risk factors for bacterial carriage were identified using questionnaires and analysed using multivariate logistic regression.

RESULTS

A total of 410 participants (336 CLD+, 74 CLD-) were enrolled (median age, 15 years [IQR = 13-18]). SP and MC carriage in NP were higher in CLD+ than in CLD- children: 46% (154/336) vs. 26% (19/74), p = 0.008; and 14% (49/336) vs. 3% (2/74), p = 0.012, respectively. SP isolates from the NP of CLD+ children were more likely to be non-susceptible to penicillin than those from CLD- children (36% [53/144] vs 11% [2/18], p = 0.036). Methicillin-resistant SA was uncommon [4% (7/195)]. In multivariate analysis, key factors associated with NP bacterial carriage included having CLD (SP: adjusted odds ratio (aOR) 2 [95% CI 1.1-3.9]), younger age (SP: aOR 3.2 [1.8-5.8]), viral load suppression (SP: aOR 0.6 [0.4-1.0], SA: 0.5 [0.3-0.9]), stunting (SP: aOR 1.6 [1.1-2.6]) and male sex (SA: aOR 1.7 [1.0-2.9]). Sputum bacterial carriage was similar in both groups (50%) and was associated with Zimbabwean site (SP: aOR 3.1 [1.4-7.3], SA: 2.1 [1.1-4.2]), being on ART for a longer period (SP: aOR 0.3 [0.1-0.8]), and hot compared to rainy season (SP: aOR 2.3 [1.2-4.4]).

CONCLUSIONS

CLD+ CLWH were more likely to be colonised by MC and SP, including penicillin-non-susceptible SP strains, than CLD- CLWH. The role of these bacteria in CLD pathogenesis, including the risk of acute exacerbations, should be further studied.

Effect of Once-Weekly Azithromycin vs Placebo in Children With HIV-Associated Chronic Lung Disease: The BREATHE Randomized Clinical Trial

IMPORTANCE

HIV-associated chronic lung disease (HCLD) in children is associated with small airways disease, is common despite antiretroviral therapy (ART), and is associated with substantial morbidity. Azithromycin has antibiotic and immunomodulatory activity and may be effective in treating HCLD through reducing respiratory tract infections and inflammation.

OBJECTIVE

To determine whether prophylactic azithromycin is effective in preventing worsening of lung function and in reducing acute respiratory exacerbations (AREs) in children with HCLD taking ART.

DESIGN, SETTING, AND PARTICIPANTS

This double-blind, placebo-controlled, randomized clinical trial (BREATHE) was conducted between 2016 and 2019, including 12 months of follow-up, at outpatient HIV clinics in 2 public sector hospitals in Malawi and Zimbabwe. Participants were randomized 1:1 to intervention or placebo, and participants and study personnel were blinded to treatment allocation. Participants included children aged 6 to 19 years with perinatally acquired HIV and HCLD (defined as forced expiratory volume in 1 second [FEV1] z score < -1) who were taking ART for 6 months or longer. Data analysis was performed from September 2019 to April 2020.

INTERVENTION

Once-weekly oral azithromycin with weight-based dosing, for 48 weeks.

MAIN OUTCOMES AND MEASURES

All outcomes were prespecified. The primary outcome was the mean difference in FEV1 z score using intention-to-treat analysis for participants seen at end line. Secondary outcomes included AREs, all-cause hospitalizations, mortality, and weight-for-age z score.

RESULTS

A total of 347 individuals (median [interquartile range] age, 15.3 [12.7-17.7] years; 177 boys [51.0%]) were randomized, 174 to the azithromycin group and 173 to the placebo group; 162 participants in the azithromycin group and 146 placebo group participants had a primary outcome available and were analyzed. The mean difference in FEV1 z score was 0.06 (95% CI, -0.10 to 0.21; P = .48) higher in the azithromycin group than in the placebo group, a nonsignificant difference. The rate of AREs was 12.1 events per 100 person-years in the azithromycin group and 24.7 events per 100 person-years in the placebo groups (hazard ratio, 0.50; 95% CI, 0.27 to 0.93; P = .03). The hospitalization rate was 1.3 events per 100 person-years in the azithromycin group and 7.1 events per 100 person-years in the placebo groups, but the difference was not significant (hazard ratio, 0.24; 95% CI, 0.06 to 1.07; P = .06). Three deaths occurred, all in the placebo group. The mean weight-for-age z score was 0.03 (95% CI, -0.08 to 0.14; P = .56) higher in the azithromycin group than in the placebo group, although the difference was not significant. There were no drug-related severe adverse events.

CONCLUSIONS AND RELEVANCE

In this randomized clinical trial specifically addressing childhood HCLD, once-weekly azithromycin did not improve lung function or growth but was associated with reduced AREs; the number of hospitalizations was also lower in the azithromycin group but the difference was not significant. Future research should identify patient groups who would benefit most from this intervention and optimum treatment length, to maximize benefits while reducing the risk of antimicrobial resistance.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02426112.

Examining the Complex Relationship Between Tuberculosis and Other Infectious Diseases in Children

Millions of children are exposed to tuberculosis (TB) each year, many of which become infected with Mycobacterium tuberculosis. Most children can immunologically contain or eradicate the organism without pathology developing. However, in a minority, the organism overcomes the immunological constraints, proliferates and causes TB disease. Each year a million children develop TB disease, with a quarter dying. While it is known that young children and those with immunodeficiencies are at increased risk of progression from TB infection to TB disease, our understanding of risk factors for this transition is limited. The most immunologically disruptive process that can happen during childhood is infection with another pathogen and yet the impact of co-infections on TB risk is poorly investigated. Many diseases have overlapping geographical distributions to TB and affect similar patient populations. It is therefore likely that infection with viruses, bacteria, fungi and protozoa may impact on the risk of developing TB disease following exposure and infection, although disentangling correlation and causation is challenging. As vaccinations also disrupt immunological pathways, these may also impact on TB risk. In this article we describe the pediatric immune response to M. tuberculosis and then review the existing evidence of the impact of co-infection with other pathogens, as well as vaccination, on the host response to M. tuberculosis. We focus on the impact of other organisms on the risk of TB disease in children, in particularly evaluating if co-infections drive host immune responses in an age-dependent way. We finally propose priorities for future research in this field. An improved understanding of the impact of co-infections on TB could assist in TB control strategies, vaccine development (for TB vaccines or vaccines for other organisms), TB treatment approaches and TB diagnostics.

An Infant with Interstitial Lung Disease

Interstitial lung disease in infants, unlike older children and adults, has diverse etiology, including infective, metabolic, autoimmune, genetic, malignant and idiopathic causes. Clinical recognition of the interstitial pattern of lung involvement is important as the etiology and management is entirely different from that of recurrent or chronic lung parenchymal pathologies. We discuss the clinical and pathological findings of an infant with interstitial pneumonia, who succumbed to hospital-acquired sepsis.

Contribution of HIV Infection, AIDS, and Antiretroviral Therapy to Exocrine Pathogenesis in Salivary and Lacrimal Glands

The structure and function of exocrine glands are negatively affected by human immunodeficiency virus (HIV) infection and its co-morbidities, including innate and adaptive immune responses. At the same time, exocrine function may also be influenced by pharmacotherapies directed at the infectious agents. Here, we briefly review the role of the salivary glands and lacrimal glands in normal physiology and exocrine pathogenesis within the context of HIV infection and acquired immune deficiency syndrome (AIDS), including the contribution of antiretroviral therapies on both. Subsequently, we discuss the impact of HIV infection and the types of antiretroviral therapy on disease management and therapy development efforts.

Expression of pIgR in the tracheal mucosa of SHIV/SIV-infected rhesus macaques

Polymeric immunoglobulin receptors (pIgR) are key participants in the formation and secretion of secretory IgA (S-IgA), which is critical for the prevention of microbial infection and colonization in the respiratory system. Although increased respiratory colonization and infections are common in HIV/AIDS, little is known about the expression of pIgR in the airway mucosa of these patients. To address this, the expression levels of pIgR in the tracheal mucosa and lungs of SHIV/SIV-infected rhesus macaques were examined by real-time RTPCR and confocal microscopy. We found that the levels of both PIGR mRNA and pIgR immunoreactivity were lower in the tracheal mucosa of SHIV/SIV-infected rhesus macaques than that in non-infected rhesus macaques, and the difference in pIgR immunoreactivity was statistically significant. IL-17A, which enhances pIgR expression, was also changed in the same direction as that of pIgR. In contrast to changes in the tracheal mucosa, pIgR and IL-17A levels were higher in the lungs of infected rhesus macaques. These results indicated abnormal pIgR expression in SHIV/SIV, and by extension HIV infections, which might partially result from IL-17A alterations and might contribute to the increased microbial colonization and infection related to pulmonary complications in HIV/AIDS.

Bronchiectasis and other chronic lung diseases in adolescents living with HIV

PURPOSE OF REVIEW

The incidence of pulmonary infections has declined dramatically with improved access to antiretroviral therapy (ART) and cotrimoxazole prophylaxis, but chronic lung disease (CLD) is an increasingly recognized but poorly understood complication in adolescents with perinatally acquired HIV.

RECENT FINDINGS

There is a high prevalence of chronic respiratory symptoms, abnormal spirometry and chest radiographic abnormalities among HIV-infected adolescents in sub-Saharan Africa, wherein 90% of the world's HIV-infected children live. The incidence of lymphocytic interstitial pneumonitis, the most common cause of CLD in the pre-ART era, has declined with increased ART access. Small airways disease, particularly constrictive obliterative bronchiolitis and bronchiectasis, are emerging as leading causes of CLD among HIV-infected adolescents in low-income and middle-income countries. Asthma may be more common in high-income settings. Likely risk factors for CLD include recurrent pulmonary infections, air pollution, HIV-related immune dysfunction, and untreated HIV infection, particularly during critical stages of lung development.

SUMMARY

Globally, the importance of HIV-associated CLD as a cause of morbidity and mortality is increasing, especially as survival has improved dramatically with ART and growing numbers of children living with HIV enter adolescence. Further research is urgently needed to elucidate the natural history and pathogenesis of CLD, and to determine optimal screening, diagnostic and treatment strategies.

A systemic review of tuberculosis with HIV coinfection in children

The epidemiology of tuberculosis is adversely impacted by the human immunodeficiency virus (HIV) coinfection. HIV-infected patients are more prone to opportunistic infections, most commonly tuberculosis, and the risk of death in coinfected patients is higher than in those without HIV. Due to the impaired cellular immunity and reduced immunological response in HIV-infected patients, the classic imaging features of tuberculosis usually seen in patients without HIV may present differently. The aim of this review article is to highlight the imaging features that may assist in the diagnosis of tuberculosis in patients with HIV coinfection.

Spirometry in Asthma Care: A Review of the Trends and Challenges in Pediatric Practice

BACKGROUND

Given the rising incidence of noncommunicable diseases (NCDs) globally, especially bronchial asthma, there is the need to reduce the associated morbidity and mortality by adopting an objective means of diagnosis and monitoring.

AIM

This article aims to review the trends and challenges in the use of spirometry for managing childhood bronchial asthma especially in developing countries.

METHODS

We conducted a literature search of published data on the use of spirometry for the diagnosis of childhood bronchial asthma with special emphasis resource-poor countries.

RESULTS

Guidelines for the diagnosis and treatment of childhood asthma recommend the use of spirometry, but this is currently underused in both tertiary and primary care settings especially in developing countries. Lack of spirometers and proper training in their use and interpretation of findings as well as a dearth of asthma guidelines remains core to the underuse of spirometry in managing children with asthma. Targeting education of health care staff was, however, observed to improve its utility, and practical implementable strategies are highlighted.

CONCLUSIONS

Spirometry is not frequently used for asthma diagnosis in pediatric practice especially in resource-poor countries where the NCD burden is higher. Strategies to overcome the obstacles are implementable and can make a difference in reducing the burden of NCD.

Lung Function in South African Adolescents Infected Perinatally with HIV and Treated Long-Term with Antiretroviral Therapy

RATIONALE

Lung disease is a common cause of mortality and morbidity in HIV-infected adolescents, but there is limited information on the spectrum of lung function impairment in adolescents on antiretroviral therapy.

OBJECTIVES

To investigate lung function in HIV-infected adolescents on antiretroviral therapy in the Cape Town Adolescent Antiretroviral Cohort (Cape Town, South Africa).

METHODS

A total of 515 South African adolescents, aged 9-14 years, stable on antiretroviral therapy for at least 6 months, underwent baseline lung function testing. Measures included spirometry, nitrogen multiple-breath washout, forced oscillation technique, 6-minute walk test, single-breath carbon monoxide diffusion testing, and bronchodilator response testing. A comparator group of 110 age- and ethnicity-matched HIV-uninfected adolescents was also tested.

RESULTS

For the HIV-infected adolescents (mean [SD] age 12 [1.6] years, 52% male), the median (interquartile range) duration of antiretroviral therapy was 7.6 (4.6-9.2) years. The median (interquartile range) nadir CD4 was 510.5 (274-903) cells/mm3. HIV-infected adolescents had significantly lower FEV1, FVC, FEV1/FVC, diffusing capacity of carbon monoxide, respiratory system compliance, and functional residual capacity than HIV-uninfected adolescents (P < 0.05 for all associations). HIV-infected adolescents had higher airway resistance and lung clearance index than HIV-uninfected adolescents (P < 0.05 for all associations). Although generally small in magnitude, these differences remained significant after adjusting for age, sex, and height. In addition, age, sex, height, and history of past lower respiratory tract infection or pulmonary tuberculosis were associated with reduced lung function.

CONCLUSIONS

Perinatally infected South African HIV-infected adolescents on antiretroviral therapy have lower lung function than uninfected adolescents. Prior lower respiratory tract infection or pulmonary tuberculosis is associated with lower lung function.

Risk Factors for Hypoxia and Tachypnea Among Adolescents With Vertically-acquired HIV in Nairobi

BACKGROUND

Chronic lung diseases are increasingly recognized complications of vertically-acquired HIV among adolescents in sub-Saharan Africa and may manifest with hypoxia or tachypnea. We sought to determine the prevalence of and risk factors for hypoxia and tachypnea among adolescents with vertically-acquired HIV in Nairobi, Kenya.

METHODS

We performed a cross-sectional analysis of 258 adolescents with vertically-acquired HIV who were initiating care at the Coptic Hope Center for Infectious Diseases. Adolescents with documented pneumonia were excluded. Hypoxia was defined as resting oxygen saturation ≤92%, and tachypnea was based on the 99th percentile of age-appropriate respiratory rates. Logistic regression models adjusted for demographics, and HIV severity estimated odds ratios for risk of hypoxia and tachypnea associated with potential risk factors.

RESULTS

Overall, 11% of adolescents had hypoxia and 55% had tachypnea. Advanced HIV [adjusted odds ratio (aOR): 2.41] and low CD4 (aOR: 1.74) were associated with greater hypoxia risk, but confidence intervals (CIs) were wide and included the null (95% CI: 0.93-6.23 and 0.69-4.39, respectively). Low CD4 (aOR: 2.45, 95% CI: 1.39-4.32), current antiretroviral therapy use (aOR: 0.48, 95% CI: 0.27-0.86) and stunted growth (aOR: 3.46, 95% CI: 1.94-6.18) were associated with altered tachypnea risk.

CONCLUSIONS

Hypoxia and tachypnea are common among adolescents with vertically-acquired HIV. There was a suggestion that advanced HIV and low CD4 were associated with greater hypoxia risk. Low CD4, lack of antiretroviral therapy use and stunted growth are risk factors for tachypnea. Our findings highlight the chronic lung disease burden in this population and may inform diagnostic algorithms.

Virus-Bacteria Interactions: An Emerging Topic in Human Infection

Bacteria and viruses often occupy the same niches, however, interest in their potential collaboration in promoting wellness or disease states has only recently gained traction. While the interaction of some bacteria and viruses is well characterized (e.g., influenza virus), researchers are typically more interested in the location of the infection than the manner of cooperation. There are two overarching types of bacterial-virus disease causing interactions: direct interactions that in some way aid the viruses, and indirect interactions aiding bacteria. The virus-promoting direct interactions occur when the virus exploits a bacterial component to facilitate penetration into the host cell. Conversely, indirect interactions result in increased bacterial pathogenesis as a consequence of viral infection. Enteric viruses mainly utilize the direct pathway, while respiratory viruses largely affect bacteria in an indirect fashion. This review focuses on some key examples of how virus-bacteria interactions impact the infection process across the two organ systems, and provides evidence supporting this as an emerging theme in infectious disease.

Chronic lung disease in HIV-infected children established on antiretroviral therapy

Objective:

Respiratory disease is a major cause of morbidity and mortality in HIV-infected children. Despite antiretroviral therapy (ART), children suffer chronic symptoms. We investigated symptom prevalence, lung function and exercise capacity among older children established on ART and an age-matched HIV-uninfected group.

Design:

A cross-sectional study in Zimbabwe of HIV-infected children aged 6–16 years receiving ART for over 6 months and HIV-uninfected children attending primary health clinics from the same area.

Methods:

Standardized questionnaire, spirometry, incremental shuttle walk testing, CD4⁺ cell count, HIV viral load and sputum culture for tuberculosis were performed.

Results:

A total of 202 HIV-infected and 150 uninfected participants (median age 11.1 years in each group) were recruited. Median age at HIV diagnosis and ART initiation was 5.5 (interquartile range 2.8–7.5) and 6.1 (interquartile range 3.6–8.4) years, respectively. Median CD4⁺ cell count was 726 cells/μl, and 79% had HIV viral load less than 400 copies/ml. Chronic respiratory symptoms were rare in HIV-uninfected children [n = 1 (0.7%)], but common in HIV-infected participants [51 (25%)], especially cough [30 (15%)] and dyspnoea [30 (15%)]. HIV-infected participants were more commonly previously treated for tuberculosis [76 (38%) vs 1 (0.7%), P < 0.001], had lower exercise capacity (mean incremental shuttle walk testing distance 771 vs 889 m, respectively, P < 0.001) and more frequently abnormal spirometry [43 (24.3%) vs 15 (11.5%), P = 0.003] compared with HIV-uninfected participants. HIV diagnosis at an older age was associated with lung function abnormality (P = 0.025). No participant tested positive for Mycobacterium tuberculosis.

Conclusion:

In children, despite ART, HIV is associated with significant respiratory symptoms and functional impairment. Understanding pathogenesis is key, as new treatment strategies are urgently required.

Case-based discussion: Lymphocytic interstitial pneumonia a rare presentation in an immunocompetent adult male

Lymphocytic interstitial pneumonia (LIP) is a rare form of interstitial lung disease usually associated with other systemic diseases; however, idiopathic cases are being reported. As per recent ATS/ERS 2013 guidelines, diagnostic criteria of clinical, radiological and histopathological for LIP is same as 2002 except some cystic changes on HRCT chest. Many cases diagnosed in the past as LIP now turn out to be NSIP; therefore as per new ATS/ERS classification whenever anybody report a case of LIP, NSIP should always be kept in mind as differential diagnosis. Here we present a case of LIP in an immunocompetent adult male presented with history of persistent dry cough and breathlessness on exertion, confirmed on HRCT chest and histopathologically, treated successfully with steroids.

Interstitial Lung Disease in Childhood: Clinical and Genetic Aspects

Interstitial lung disease (ILD) in childhood is a heterogeneous group of rare pulmonary conditions presenting chronic respiratory disorders. Many clinical features of ILD still remain unclear, making the treatment strategies mainly investigative. Guidelines may provide physicians with an overview on the diagnosis and therapeutic directions. However, the criteria used in different clinical studies for the classification and diagnosis of ILDs are not always the same, making the development of guidelines difficult. Advances in genetic testing have thrown light on some etiologies of ILD, which were formerly classified as ILDs of unknown origins. The need of genetic testing for unexplained ILD is growing, and new classification criteria based on the etiology should be adopted to better understand the disease. The purpose of this review is to give an overview of the clinical and genetic aspects of ILD in children.

The chest X-ray features of chronic respiratory disease in HIV-infected children--a review

Several features of human immunodeficiency virus (HIV) infection contribute to the development of chronic respiratory disease in children. These include the frequency and severity of acute chest infections, as well as the increased risk of pulmonary tuberculosis, aspiration, cardiovascular disease, lymphocytic interstitial pneumonitis or pulmonary neoplasia. The chest radiograph (CXR) remains the most accessible investigation for respiratory disease and plays an important role in the baseline assessment and follow-up. This review focuses on the CXR abnormalities of HIV-related chronic respiratory disease in children. The most commonly documented chronic CXR abnormalities are homogeneous opacification and pulmonary nodules, with pulmonary tuberculosis and lymphocytic interstitial pneumonitis the leading respective causes. Deficiencies in radiographic reporting methodology and relative paucity of radiographic data contribute to current limitations in knowledge and understanding of this field. The review highlights the need for standardised terminology and systematic reporting methodology in future studies. Prospective research on the natural history of lymphocytic interstitial pneumonitis, response to anti-tuberculous therapy, the impact of anti-retroviral therapy and HIV-associated bronchiectasis are needed.

Chest radiographic abnormalities in HIV-infected African children: a longitudinal study

BACKGROUND

There is limited knowledge of chest radiographic abnormalities over time in HIV-infected children in resource-limited settings.

OBJECTIVE

To investigate the natural history of chest radiographic abnormalities in HIV-infected African children, and the impact of antiretroviral therapy (ART).

METHODS

Prospective longitudinal study of the association of chest radiographic findings with clinical and immunological parameters. Chest radiographs were performed at enrolment, 6-monthly, when initiating ART and if indicated clinically. Radiographic abnormalities were classified as normal, mild or moderate severity and considered persistent if present for 6 consecutive months or longer. An ordinal multiple logistic regression model assessed the association of enrolment and time-dependent variables with temporal radiographic findings.

RESULTS

258 children (median (IQR) age: 28 (13-51) months; median CD4+%: 21 (15-24)) were followed for a median of 24 (18-42) months. 70 (27%) were on ART at enrolment; 130 (50%) (median age: 33 (18-56) months) commenced ART during the study. 154 (60%) had persistent severe radiographic abnormalities, with median duration 18 (6-24) months. Among children on ART, 69% of radiographic changes across all 6-month transition periods were improvements, compared with 45% in those not on ART. Radiographic severity was associated with previous radiographic severity (OR=120.80; 95% CI 68.71 to 212.38), lack of ART (OR=1.72; 95% CI 1.29 to 2.27), enrolment age <18 months (OR=1.39; 95% CI 1.06 to 1.83), diffuse, severe radiographic abnormality at enrolment (OR=2.18; 95% CI 1.33 to 3.56), hospitalisation for lower respiratory tract infection during the previous 6 months (OR=1.88; 95% CI 1.06 to 3.30) and length of follow-up: at 18-24 months (OR=0.66; 95% CI 0.49 to 0.90), and at 30-54 months (OR=0.42; 95% CI 0.32 to 0.56).

CONCLUSIONS

Most children had severe radiographic abnormalities persisting for at least 18 months. ART was beneficial, reducing the risk of radiographic deterioration or increasing the likelihood of radiological improvement.

The Lung Immune Response to Nontypeable Haemophilus influenzae (Lung Immunity to NTHi)

Haemophilus influenzae is divided into typeable or nontypeable strains based on the presence or absence of a polysaccharide capsule. The typeable strains (such as type b) are an important cause of systemic infection, whilst the nontypeable strains (designated as NTHi) are predominantly respiratory mucosal pathogens. NTHi is present as part of the normal microbiome in the nasopharynx, from where it may spread down to the lower respiratory tract. In this context it is no longer a commensal and becomes an important respiratory pathogen associated with a range of common conditions including bronchitis, bronchiectasis, pneumonia, and particularly chronic obstructive pulmonary disease. NTHi induces a strong inflammatory response in the respiratory tract with activation of immune responses, which often fail to clear the bacteria from the lung. This results in recurrent/persistent infection and chronic inflammation with consequent lung pathology. This review will summarise the current literature about the lung immune response to nontypeable Haemophilus influenzae, a topic that has important implications for patient management.

The diffuse infiltrative lymphocytosis syndrome (DILS). A comprehensive review

The Diffuse Infiltrative Lymphocytosis Syndrome (DILS) is a rare multisystemic syndrome described in HIV-infected patients. It is characterised by CD8(+) T-cell lymphocytosis associated with a CD8(+) T-cell infiltration of multiple organs. DILS is usually seen in uncontrolled or untreated HIV infection but can also manifest itself independently of CD4(+) T-cell counts. The syndrome may present as a Sjögren-like disease that generally associates sicca signs with bilateral parotiditis, lymphadenopathy, and extraglandular organ involvement. The latter may affect the lungs, nervous system, liver, kidneys, and digestive tract. Anomalies of the respiratory system are often identified as lymphocytic interstitial pneumonia. Facial nerve palsy, aseptic meningitis or polyneuropathy are among the more frequent neurological features. Hepatic lymphocytic infiltration, lymphocytic interstitial nephropathy and digestive tract lymphocytic infiltration account for more rarely noted complications. Sicca syndrome, organomegaly and/or organ dysfunction associated with polyclonal CD8(+) T-cell organ-infiltration are greatly suggestive of DILS in people living with HIV. Labial salivary gland biopsy is therefore helpful when the focus score is equal or greater than 1 (or Chisholm Score ≥ 3). Primary Sjögren syndrome, chronic HCV or HTLV1 infection, graft versus host disease, IgG4-related disease, and immune reconstitution inflammatory syndrome are among the differential diagnoses that need to be considered. Treatment consists in highly active anti-retroviral therapy (HAART), which is usually effective in resolving clinical signs and symptoms. Steroids, however, may also be occasionally required when organ infiltration does not respond to HAART. This review should provide an insight into this rare entity complicating the course of HIV infection.

Application of clinico-radiologic-pathologic diagnosis of diffuse parenchymal lung diseases in children in China

Diffuse parenchymal lung diseases in children (chDPLD) or interstitial lung diseases in children (chILD) represent a heterogeneous group of respiratory disorders that are mostly chronic and associated with high morbidity and mortality. However, the incidence of chDPLD is so low that most pediatricians lack sufficient knowledge of chDPLD, especially in China. Based on the clinico-radiologic-pathologic (CRP) diagnosis, we tried to describe (1) the characteristics of chDPLD and (2) the ratio of each constituent of chDPLD in China. Data were evaluated, including clinical, radiographic, and pathologic results from lung biopsies. We collected 25 cases of chDPLD, 18 boys and 7 girls with a median age of 6.0 years, from 16 hospitals in China. The most common manifestations included cough (n = 24), dyspnea (n = 21), and fever (n = 4). There were three cases of exposure-related interstitial lung disease (ILD), three cases of systemic disease-associated ILD, nineteen cases of alveolar structure disorder-associated ILD, and no cases of ILD specific to infancy. Non-specific interstitial pneumonia (n = 9) was the two largest groups.

CONCLUSION

Non-specific interstitial pneumonia is the main categories of chDPLD in China. Lung biopsy is always a crucial step in the final diagnosis. However, clinical and imaging studies should be carefully evaluated for their value in indicating a specific chDPLD.

Clinical and immunological correlates of chest X-ray abnormalities in HIV-infected South African children with limited access to anti-retroviral therapy

BACKGROUND

The chest X-ray (CXR) abnormalities of human immunodeficiency virus (HIV)-infected children in low/middle income countries (LMIC's) have not been well studied.

OBJECTIVE

To describe the CXR abnormalities and associated clinical/immunological features in HIV-infected South African children.

MATERIALS AND METHODS

A prospective study of HIV-infected children who underwent baseline chest radiography and clinical and immunological HIV-staging. CXR abnormalities were stratified as grade 1 (mild) or grade 2 (moderate/severe). Univariate and multiple logistic regression analyses assessed associations between radiological severity and clinical/immunological parameters.

RESULTS

Three hundred thirty children (53% male), median age 23.8 months, were included; 303 (92%) had moderate/severe clinical disease and 225 (68%) moderate/severe immune suppression; 52 (16%) had a normal CXR; 169 (51%) had grade 2 CXR abnormalities, manifesting as: confluent opacification (n = 91, 28%), nodules (n = 37, 11%), or nodules with opacification (n = 41, 12%) Grade 2 abnormality was associated with more advanced clinical HIV disease (OR: 6.9; 95% CI: 1.9-25.6), CD4+ less than 20% (OR: 1.8; 95% CI: 1.0-3.0) and age over 24 months (OR: 4.1; 95% CI: 2.1-8.0).

CONCLUSION

CXR abnormalities are common in HIV-infected children in LMIC's. The extent of radiological abnormality correlates with age and clinical and immunological severity of HIV-disease.

Perinatally acquired HIV infection in adolescents from sub-Saharan Africa: a review of emerging challenges

Worldwide, more than three million children are infected with HIV, 90% of whom live in sub-Saharan Africa. As the HIV epidemic matures and antiretroviral treatment is scaled up, children with HIV are reaching adolescence in large numbers. The growing population of adolescents with perinatally acquired HIV infection living within this region presents not only unprecedented challenges but also opportunities to learn about the pathogenesis of HIV infection. In this Review, we discuss the changing epidemiology of paediatric HIV and the particular features of HIV infection in adolescents in sub-Saharan Africa. Longstanding HIV infection acquired when the immune system is not developed results in distinctive chronic clinical complications that cause severe morbidity. As well as dealing with chronic illness, HIV-infected adolescents have to confront psychosocial issues, maintain adherence to drugs, and learn to negotiate sexual relationships, while undergoing rapid physical and psychological development. Context-specific strategies for early identification of HIV infection in children and prompt linkage to care need to be developed. Clinical HIV care should integrate age-appropriate sexual and reproductive health and psychological, educational, and social services. Health-care workers will need to be trained to recognise and manage the needs of these young people so that the increasing numbers of children surviving to adolescence can access quality care beyond specialist services at low-level health-care facilities.

The challenge of chronic lung disease in HIV-infected children and adolescents

Until recently, little attention has been given to chronic lung disease (CLD) in HIV-infected children. As the HIV epidemic matures in sub-Saharan Africa, adolescents who acquired HIV by vertical transmission are presenting to health services with chronic diseases. The most common is CLD, which is often debilitating. This review summarizes the limited data available on the epidemiology, pathophysiology, clinical picture, special investigations and management of CLD in HIV-infected adolescents. A number of associated conditions: lymphocytic interstitial pneumonitis, tuberculosis and bronchiectasis are well described. Other pathologies such as HIV-associated bronchiolitis obliterans resulting in non-reversible airway obstruction, has only recently been described. In this field, there are many areas of uncertainty needing urgent research. These areas include the definition of CLD, pathophysiological mechanisms and common pathologies responsible. Very limited data are available to formulate an effective plan of investigation and management.

Infektionen

Die Meldung und Erfassung von Infektionskrankheiten ist in Deutschland durch das Infektionsschutzgesetz (IfSG) geregelt. In §6 sind meldepflichtige Krankheiten nach gewissen Vorgaben geregelt.

Waiting to inhale: An exploratory review of conditions that may predispose to pulmonary hypertension and right heart failure in persons exposed to household air pollution in low- and middle-income countries

The health effects of exposure to household air pollution are gaining international attention. While the bulk of the known mortality estimates due to these exposures are derived from respiratory conditions, there is growing evidence of adverse cardiovascular health effects. Pulmonary hypertension and right heart failure are common conditions in low- and middle-income countries whose etiology may be related to common exposures in these regions such as schistosomiasis, human immunodeficiency virus, tuberculosis infections and other causes. While little is known of the interplay between exposure to household air pollution, right heart function and such conditions, the large burden of pulmonary hypertension and right heart failure in regions where there is significant exposure to household air pollution raises the possibility of a linkage. This review is presented in three parts. First, we explore what is known about pulmonary hypertension and right heart failure in low- and middle-income countries by focusing on eight common causes thereof. We then review what is known of the impact of household air pollution on pulmonary hypertension and posit that when individuals with one of these eight common comorbidities are exposed to household air pollution they may be predisposed to develop pulmonary hypertension or right heart failure. Lastly, we posit that there may be a direct link between exposure to household air pollution and right heart failure independent of pre-existing conditions which merits further investigation. Our overall aim is to highlight the multifactorial nature of these complex relationships and offer avenues for research in this expanding field of study.

Surgical implications of human immunodeficiency virus infections

Pediatric HIV (human immunodeficiency virus) is a pandemic predominantly in sub-Saharan Africa. Approximately 2.2 million children aged less than 15 years are infected with HIV, representing almost 95% of the total number of children globally infected with HIV. Therefore, increasing numbers of HIVi or -exposed but uninfected children can be expected to require a surgical procedure to assist in the diagnosis of an HIV/acquired immune deficiency syndrome-related complication, to address a life-threatening complication of the disease, or for routine surgery encountered in HIV-unexposed children. HIVi children may present with both conditions unique to HIV infection and surgical conditions routine in pediatric surgical practice. HIV exposure confers an increased risk of complications and mortality for all children after surgery, whether they are HIV infected or not. This risk of complications is higher in the HIVi group of patients. These findings seem to be independent of whether patients undergo an elective or emergency procedure, but the risk of an adverse outcome is higher for a major procedure. Surgical implications of HIV infection are comprehensively reviewed in this article.

Chronic lung disease in adolescents with delayed diagnosis of vertically acquired HIV infection

A high burden of chronic lung disease (CLD) was found among 116 consecutive adolescents with vertically acquired human immunodeficiency virus in Zimbabwe. The main cause of HIV-associated CLD appears to be obliterative bronchiolitis, which has not previously been recognized among this patient group.

Background. Long-term survivors of vertically acquired human immunodeficiency virus (HIV) infection are reaching adolescence in large numbers in Africa and are at high risk of delayed diagnosis and chronic complications of untreated HIV infection. Chronic respiratory symptoms are more common than would be anticipated based on the HIV literature.

Methods. Consecutive adolescents with presumed vertically acquired HIV attending 2 HIV care clinics in Harare, Zimbabwe, were recruited and assessed with clinical history and examination, CD4 count, pulmonary function tests, Doppler echocardiography, and chest radiography (CXR). Those with suspected nontuberculous chronic lung disease (CLD) were scanned using high-resolution computed tomography (HRCT).

Results. Of 116 participants (43% male; mean age, 14 ± 2.6 years, mean age at HIV diagnosis, 12 years), 69% were receiving antiretroviral therapy. Chronic cough and reduced exercise tolerance were reported by 66% and 21% of participants, respectively; 41% reported multiple respiratory tract infections in the previous year, and 10% were clubbed. More than 40% had hypoxemia at rest (13%) or on exercise (29%), with pulmonary hypertension (mean pulmonary artery pressure >25 mm Hg) in 7%. Forced expiratory volume in 1 second (FEV₁) was <80% predicted in 45%, and 47% had subtle CXR abnormalities. The predominant HRCT pattern was decreased attenuation as part of a mosaic attenuation pattern (31 of 56 [55%]), consistent with small airway disease and associated with bronchiectasis (Spearman correlation coefficient (r² = 0.8) and reduced FEV₁ (r² = −0.26).

Conclusions. Long-term survivors of vertically acquired HIV in Africa are at high risk of a previously undescribed small airway disease, with >40% of unselected adolescent clinic attendees meeting criteria for severe hypoxic CLD. This condition is not obvious at rest. Etiology, prognosis, and response to treatment are currently unknown.

Small ruminant lentiviruses: immunopathogenesis of visna-maedi and caprine arthritis and encephalitis virus

The small ruminant lentiviruses include the prototype for the genus, visna-maedi virus (VMV) as well as caprine arthritis encephalitis virus (CAEV). Infection of sheep or goats with these viruses causes slow, progressive, inflammatory pathology in many tissues, but the most common clinical signs result from pathology in the lung, mammary gland, central nervous system and joints. This review examines replication, immunity to and pathogenesis of these viruses and highlights major differences from and similarities to some of the other lentiviruses.

Increased risk of asthma and atopic dermatitis in perinatally HIV-infected children and adolescents

The incidence of asthma and atopic dermatitis (AD) was evaluated in HIV-infected (n = 451) compared to HIV-exposed (n = 227) but uninfected (HEU) children and adolescents by abstraction from clinical charts. Asthma was more common in HIV-infected compared to HEU children by clinical diagnosis (25% vs. 20%, p = 0.101), by asthma medication use, (31% vs. 22%, p = 0.012), and by clinical diagnosis and/or medication use, (34% vs. 25%, p = 0.012). HIV-infected children had a greater risk of asthma compared to HEU children (HR = 1.37, 95% CI: 1.01 to 1.86). AD was more common in HIV-infected than HEU children (20% vs. 12%, p = 0.009)) and children with AD were more likely to have asthma in both cohorts (41% vs. 29%, p = 0.010). HIV-infected children and adolescents in this study had an increased incidence of asthma and AD, a finding critical for millions of HIV-infected children worldwide.

Chest radiography patterns in 75 adolescents with vertically-acquired human immunodeficiency virus (HIV) infection

Aim

To evaluate lung disease on chest radiography (CR), the relative frequency of CR abnormalities, and their clinical correlates in adolescents with vertically-acquired human immunodeficiency virus (HIV) infection.

Materials and methods

CRs of 75 patients [59 inpatients (33 males; mean age 13.7 ± 2.3 years) and 16 outpatients (eight males; mean age 14.1 ± 2.1 years)] were retrospectively reviewed by three independent observers. The overall extent of disease (to the nearest 5%), its distribution, and the proportional extents (totalling 100%) of different radiographic patterns (including ring/tramline opacities and consolidation) were quantified. CR features and clinical data were compared.

Results

CRs were abnormal in 51/75 (68%) with “extensive” disease in 38/51 (74%). Ring/tramline opacities and consolidation predominated (i.e., proportional extent >50%) in 26 and 21 patients, respectively. Consolidation was significantly more common in patients hospitalized primarily for a respiratory illness than patients hospitalized for a non-respiratory illness or in outpatients (p < 0.005, χ² for trend); by contrast, ring/tramline opacities did not differ in prevalence across the groups. On stepwise logistic regression, predominant consolidation was associated with progressive dyspnoea [odds ratio (OR) 5.60; 95% confidence intervals (CI): 1.60, 20.1; p < 0.01] and was associated with a primary respiratory cause for hospital admission (OR: 22.0; CI: 2.7, 181.1; p < 0.005). Ring/tramline opacities were equally prevalent in patients with and without chronic symptoms and in those admitted to hospital with respiratory and non-respiratory illness.

Conclusion

In HIV-infected adolescents, evaluated in secondary practice, CR abnormalities are prevalent. The presence of ring/tramline opacities, believed to reflect chronic airway disease, is not linked chronic respiratory symptoms.

Cell reservoirs of the Epstein-Barr virus in biopsy-proven lymphocytic interstitial pneumonitis in HIV-1 subtype E infected children: identification by combined in situ hybridization and immunohistochemistry

Lymphoid interstitial pneumonitis (LIP), a frequent pulmonary complication in human immune deficiency virus (HIV)-infected pediatric patients, is characterized histologically by marked infiltration of lymphoid cells. Several theories have been suggested that LIP may be caused by Epstein-Barr virus (EBV). To identify the reservoir of EBV and pathogenesis of lymphoid infiltrates in HIV subtype E infected pediatric LIP, we examined the distribution and expression of EBV in the inflammatory cell recruitment in surgical lung biopsy-proven LIP from 9 vertically HIV subtype E-infected pediatric patients. The dominant microscopic feature of LIP demonstrated widespread widening of alveolar septum by mononuclear inflammatory cell infiltrate mainly composed of mature lymphocytes and plasma cells surrounding airways and expanding to the lung interstitium. EBV-encoded RNA (EBER) in situ hybridization, performed from paraffin-embedded lung tissues, revealed positive intranuclear signals in all 9 LIP cases. Interestingly, combined immunohistochemical and in situ hybridization analyses in 6 out of 9 LIP cases revealed 30% to 50% of the Langerhans and related dendritic cells were infected with EBV, whereas <30% of the T and B cells were infected with EBV. These results suggested that a chronic antigenic stimulus of EBV played important roles in the pathogenesis of LIP in these patients. This supports the notion that Langerhans cells (LCs) are more readily infected with EBV, indicating that LCs are reservoirs for EBV in lungs of HIV subtype E-infected pediatric LIP. And possibly LCs may play an important role in the recruitment of inflammatory cell infiltrates, especially T cells into these tissues. In addition, HIV may provide a milieu or microenvironment for the evolution of LIP, which represent an immunologic response to EBV infection. Interactions between LCs and related dendritic cells together with T cells are important for effective HIV and EBV replications.