Diagnosis and management of community-acquired pneumonia in children: South African Thoracic Society guidelines

BACKGROUND

Pneumonia remains a major cause of morbidity and mortality amongst South African children. More comprehensive immunisation regimens, strengthening of HIV programmes, improvement in socioeconomic conditions and new preventive strategies have impacted on the epidemiology of pneumonia. Furthermore, sensitive diagnostic tests and better sampling methods in young children improve aetiological diagnosis.

OBJECTIVES

To produce revised guidelines for pneumonia in South African children under 5 years of age.

METHODS

The Paediatric Assembly of the South African Thoracic Society and the National Institute for Communicable Diseases established seven expert subgroups to revise existing South African guidelines focusing on: (i) epidemiology; (ii) aetiology; (iii) diagnosis; (iv) antibiotic management and supportive therapy; (v) management in intensive care; (vi) prevention; and (vii) considerations in HIV-infected or HIVexposed, uninfected (HEU) children. Each subgroup reviewed the published evidence in their area; in the absence of evidence, expert opinion was accepted. Evidence was graded using the British Thoracic Society (BTS) grading system. Sections were synthesized into an overall guideline which underwent peer review and revision.

RECOMMENDATIONS

Recommendations include a diagnostic approach, investigations, management and preventive strategies. Specific recommendations for HIV infected and HEU children are provided.

VALIDATION

The guideline is based on available published evidence supplemented by the consensus opinion of SA paediatric experts. Recommendations are consistent with those in published international guidelines.

Acute viral bronchiolitis in South Africa: Diagnostic flow

Bronchiolitis may be diagnosed on the basis of clinical signs and symptoms. In a young child, the diagnosis can be made on the clinical pattern of wheezing and hyperinflation. Clinical symptoms and signs typically start with an upper respiratory prodrome, including rhinorrhoea, low-grade fever, cough and poor feeding, followed 1 - 2 days later by tachypnoea, hyperinflation and wheeze as a consequence of airway inflammation and air trapping.The illness is generally self limiting, but may become more severe and include signs such as grunting, nasal flaring, subcostal chest wall retractions and hypoxaemia. The most reliable clinical feature of bronchiolitis is hyperinflation of the chest, evident by loss of cardiacdullness on percussion, an upper border of the liver pushed down to below the 6th intercostal space, and the presence of a Hoover sign(subcostal recession, which occurs when a flattened diaphragm pulls laterally against the lower chest wall).Measurement of peripheral arterial oxygen saturation is useful to indicate the need for supplemental oxygen. A saturation of <92% at sea level and 90% inland indicates that the child has to be admitted to hospital for supplemental oxygen. Chest radiographs are generally unhelpful and not required in children with a clear clinical diagnosis of bronchiolitis.Blood tests are not needed routinely. Complete blood count tests have not been shown to be useful in diagnosing bronchiolitis or guiding its therapy. Routine measurement of C-reactive protein does not aid in management and nasopharyngeal aspirates are not usually done.Viral testing adds little to routine management. Risk factors in patients with severe bronchiolitis that require hospitalisation and may even cause death, include prematurity, congenital heart disease and congenital lung malformations.

Acute viral bronchiolitis in South Africa: Strategies for management and prevention

Management of acute viral bronchiolitis is largely supportive. There is currently no proven effective therapy other than oxygen for hypoxic children. The evidence indicates that there is no routine benefit from inhaled, rapid short-acting bronchodilators, adrenaline or ipratropium bromide for children with acute viral bronchiolitis. Likewise, there is no demonstrated benefit from routine use of inhaled or oral corticosteroids, inhaled hypertonic saline nebulisation, montelukast or antibiotics. The last should be reserved for children with severe disease, when bacterial co-infection is suspected. Prevention of respiratory syncytial virus (RSV) disease remains a challenge. A specific RSV monoclonal antibody, palivizumab, administered as an intramuscular injection, is available for children at risk of severe bronchiolitis, including premature infants, young children with chronic lung disease, immunodeficiency, or haemodynamically significant congenital heart disease. Prophylaxis should be commenced at the start of the RSV season and given monthly during the season. The development of an RSV vaccine may offer a more effective alternative to prevent disease, for which the results of clinical trials are awaited. Education of parents or caregivers and healthcare workers about diagnostic and management strategies should include the following: bronchiolitis is caused by a virus; it is seasonal; it may start as an upper respiratory tract infection with low-grade fever; symptoms are cough and wheeze, often with fast breathing; antibiotics are generally not needed; and the condition is usually self limiting, although symptoms may occur for up to four weeks in some children.

Value of chest radiography in predicting treatment response in children aged 3-59 months with severe pneumonia

SETTING

International multicentric study at nine tertiary care centres.

OBJECTIVE

The World Health Organization (WHO) currently does not recommend chest radiographs (CXRs) for routine management of pneumonia. We evaluated the use of CXR for the prediction of treatment failure in children with severe pneumonia.

DESIGN

We used WHO vaccine trials radiographic assessment, clinical and nasopharyngeal microbiological data from 1121 3-59-month-old children recruited using the WHO definition of severe pneumonia in the Amoxicillin Penicillin Pneumonia International Study (APPIS). Using Poisson regression, we estimated the relative risk of developing clinical treatment failure and predictive preventive benefit of the CXR and examined the concordance of the CXR findings with the nasopharyngeal microbiological data.

RESULTS

A CXR with 'significant pathology' (defined by the WHO algorithm as end-point consolidation, pleural fluid and other infiltrates) was associated with a high risk of treatment failure, especially in children who received penicillin as compared to oral amoxicillin. Significant pathology was also associated with nasopharyngeal isolation of penicillin-resistant Streptococcus pneumoniae. Children with a normal CXR had a reduced risk of clinical treatment failure.

CONCLUSIONS

CXR with significant pathology independently and additively predicts clinical treatment failure. If CXR and the WHO tool are available, they can be used in the management of severe pneumonia.

Diagnosis and management of community-acquired pneumonia in childhood--South African Thoracic Society Guidelines

BACKGROUND

Community-acquired pneumonia (CAP) is a major cause of morbidity and mortality in South African children. The incidence, severity and spectrum of childhood pneumonia have changed owing to the HIV epidemic. Increasing emergence of antimicrobial resistance necessitates a rational approach to the use of antibiotics in pneumonia management.

OBJECTIVE

To develop guidelines for the diagnosis, management and prevention of CAP in South African children.

METHODS

The Paediatric Assembly of the South African Thoracic Society established five expert subgroups to address: (i) epidemiology and aetiology; (ii) diagnosis; (iii) antibiotic treatment; (iv) supportive therapy; and (v) prevention of CAP. Each subgroup developed a position paper based on the available published evidence; in the absence of evidence, expert opinion was accepted. After peer review and revision, the position papers were synthesised into an overall guideline which was further reviewed and revised.

RECOMMENDATIONS

Recommendations based on epidemiological factors include a diagnostic approach, investigations, supportive therapy, appropriate antibiotic treatment and preventive strategies. Specific recommendations for HIV-infected children are provided.

VALIDATION

These guidelines are based on the available evidence supplemented by the consensus opinion of South African experts in paediatrics, paediatric pulmonology, radiology, infectious diseases and microbiology. Published international guidelines have also been consulted.

The HIV-1 exposed neonate: outcome of intensive care management in the first week of life

A prospective study was carried out to determine if the outcome in HIV-exposed neonates requiring intensive care (n=30) is different from that in HIV-unexposed neonates (n=40) requiring intensive care in the first week of postnatal life. It was noted that the outcome in terms of incidence of death and intensive care stay do not differ significantly in these two groups although some hematological parameters may be significantly different. Considering the fact that the outcome is not worse in HIV-exposed babies and that most of these babies ultimately turn out to be HIV-uninfected, these babies should not be deprived of intensive care, whenever necessary.

The role of HIV infection in acute respiratory infections among children in sub-Saharan Africa

Acute respiratory infections (ARI) are responsible for 1.9 million deaths annually, or 20% of the total worldwide under 5-year mortality rate. Developing countries carry the major burden of these deaths. In sub-Saharan Africa, human immunodeficiency virus type 1 (HIV-1) plays a significant role in this high mortality rate. The clinical and radiological features of ARI in HIV-infected and non-infected children are similar, with few exceptions. Epidemiological mapping of aetiological agents is essential to develop standard case management guidelines. The role of newer cytokines (e.g., procalcitonin) in establishing aetiology requires further evaluation. Implementation of antiretroviral therapy, chemoprophylaxis and vaccination programmes for HIV-infected children will have a favourable impact on the huge burden of ARI in developing countries. Governmental and nongovernmental organisations must provide the financial and human resources needed to overcome this enormous challenge to global lung health.

HIV evolution: CTL escape mutation and reversion after transmission

Within-patient HIV evolution reflects the strong selection pressure driving viral escape from cytotoxic T-lymphocyte (CTL) recognition. Whether this intrapatient accumulation of escape mutations translates into HIV evolution at the population level has not been evaluated. We studied over 300 patients drawn from the B- and C-clade epidemics, focusing on human leukocyte antigen (HLA) alleles HLA-B57 and HLA-B5801, which are associated with long-term HIV control and are therefore likely to exert strong selection pressure on the virus. The CTL response dominating acute infection in HLA-B57/5801-positive subjects drove positive selection of an escape mutation that reverted to wild-type after transmission to HLA-B57/5801-negative individuals. A second escape mutation within the epitope, by contrast, was maintained after transmission. These data show that the process of accumulation of escape mutations within HIV is not inevitable. Complex epitope- and residue-specific selection forces, including CTL-mediated positive selection pressure and virus-mediated purifying selection, operate in tandem to shape HIV evolution at the population level.

Emergence of multi-drug-resistant Acinetobacter anitratus species in neonatal and paediatric intensive care units in a developing country: concern about antimicrobial policies

Antimicrobial abuse is a serious risk factor for the emergence of multi-drug-resistant (MDR) pathogens. We report on the emergence of multi-drug-resistant Acinetobacter anitratus species over two 8-week periods in 1999 in the neonatal and paediatric intensive care units (NICU and PICU) of King Edward VII Hospital, Durban, South Africa. The source, transmission dynamics, microbiological evaluations, antibiotic utilization patterns and outcome were evaluated. MDR Acinetobacter anitratus was isolated from different body sites in 23 infants less than 2 months of age, 18 in the PICU and five in the NICU. The mortality was 56.5% and two survivors required re-admission. Ten of the 23 cases had entered the ICU with MDR Acinetobacter anitratus. Eleven of the study infants had received broad-spectrum antimicrobial agents before entering the ICU, while all infants with nosocomially acquired MDR Acinetobacter anitratus had received broad-spectrum antimicrobial agents. All the surgical cases with MDR Acinetobacter anitratus died. Microbiological data from both ICUs for 1999 indicated that gram-negative bacteria accounted for two-thirds of isolates, Acinetobacter anitratus and Klebsiella pneumoniae accounting for 33% and 27% of the isolates, respectively. Only 53% and 57% of all Acinetobacter spp isolates were susceptible to piperacillin/tazobactam and carbepenems, respectively. MDR Acinetobacter anitratus is an emerging problem to which antimicrobial abuse contributes.

Paediatric HIV infection: correlates of protective immunity and global perspectives in prevention and management

The impact of the HIV epidemic on child health globally is beginning to be appreciated. With the burden of new infections falling on young women, there is a skyrocketing number of AIDS orphans, and a rapidly increasing number of children infected via mother-to-child-transmission (MTCT). An estimated 600,000 new paediatric infections occur each year, of which some 1500/day (> 90%) occur in sub-Saharan Africa. But whereas children account for only 4% of those currently living with HIV infection, 20% of AIDS deaths have been in children. This reflects the rapid progression to disease in paediatric HIV infection. Whereas a dramatic reduction in viraemia follows acute adult infection, corresponding to the appearance of a vigorous anti-HIV cytotoxic T lymphocyte response, virtually no impact of the immune response is observed in acute paediatric infection following MTCT. Two specific challenges for the paediatric immune response are: (i) infection occurs before the immune system itself is fully developed; and (ii) the viruses transmitted by MTCT have already evaded an immune system sharing close genetic relatedness to that of the child. Accumulating evidence indicates that the immune system is potentially capable of effective control of HIV infection, and that events occurring in acute infection critically determine the ultimate outcome. Technological advances that have transformed the study of T-cell immunity now enable the developing immune system in childhood to be better understood. Via novel immunotherapeutic approaches described, it may be possible to modulate the infant's immune response to reach effective and durable suppression of HIV, as can be achieved by the rare long-term non-progressors of HIV infection. The feasibility of adopting these approaches globally are as yet untested. Finally, the striking disparity between the burden of paediatric HIV infection and access to the necessary infrastructure and therapeutic options required for its optimal management is addressed in a comparison between three sites of paediatric HIV care: Durban, South Africa; London, UK; and Boston, USA.

Childhood human immunodeficiency virus and tuberculosis co-infections: reconciling conflicting data

The impact of the human immunodeficiency virus (HIV) pandemic on childhood tuberculosis (TB) is unclear because of inconsistent and often contradictory findings in different types of studies. We review the evidence which supports or refutes the likelihood that HIV infection in children predisposes them to TB, and conclude that, on balance, HIV during infancy increases the risk of developing TB. Surveillance shows an association between rising TB rates among children and the HIV epidemic in some parts of the world. A number of cross-sectional studies which have taken children with TB as their starting population, have yielded high rates of association with HIV (11%-64% HIV prevalence). Similarly, cross-sectional studies of hospitalised children with HIV show that many also have TB. These rates of association are all over-estimated because of the uncertainty of diagnosis of TB. Birth cohorts of perinatally HIV-infected infants and children prospectively followed up for a few years have generally failed to detect a higher incidence of TB than anticipated. The few TB cases identified in these cohorts were usually over 15-18 months of age. In acute progressive lung disease there is no excess of TB in HIV-infected over non HIV-infected children. These inconsistencies are discussed and attributed mainly to study design and statistical artefact. However, maternal factors in HIV-positive women which might affect transmission of TB to their babies are assessed, and infant immunoparesis due to HIV which may adversely influence resistance to TB is considered.

Parotid MALT lymphoma in HIV infected children

A retrospective review of 10 children with biopsy proved mucosa-associated lymphoid tissue lymphoma of the parotid glands demonstrated multifocal hypoechoic intraparotid nodules and cysts with punctate calcification on sonography. This was confirmed on computed tomographic examination. All children were seropositive for human immunodeficiency virus and had depressed CD4 counts. Mucosa-associated lymphoid tissue lymphoma should be considered in the diagnosis of bilateral parotid swelling in children with acquired immunodeficiency disease-related complex.