Pneumocystis carinii pneumonia in South African children infected with human immunodeficiency virus

The Burden of Pneumocystis Pneumonia Infection among HIV Patients in Ethiopia: A Systematic Review

Pneumocystis pneumonia (PCP) is a leading cause of death among patients with AIDS worldwide, but its burden is difficult to estimate in low- and middle-income countries, including Ethiopia. This systematic review aimed to estimate the pooled prevalence of PCP in Ethiopia, the second most densely populated African country. The Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines were used to review published and unpublished studies conducted in Ethiopia. Studies that reported on the prevalence of PCP among HIV-infected patients were searched systematically. Variations between the studies were assessed by using forest plot and I-squared heterogeneity tests. Subgroup and sensitivity analyses were carried out when I2 > 50. The pooled estimate prevalence with 95% CI was computed using a random-effects model of analysis. Thirteen articles, comprising studies of 4847 individuals living with HIV, were included for analysis. The pooled prevalence of PCP was 5.65% (95% CI [3.74-7.56]) with high heterogeneity (I2 = 93.6%, p < 0.01). To identify the source of heterogeneity, subgroup analyses were conducted by study design, geographical region, diagnosis methods, and year of publication. PCP prevalence differed significantly when biological diagnostic methods were used (32.25%), in studies published before 2010 (32.51%), in cross-sectional studies (8.08%), and in Addis Ababa (14.05%). PCP prevalence differences of 3.25%, 3.07%, 3.23%, and 2.29% were recorded in studies based on clinical records, published since 2017, follow-up studies, and north-west Ethiopian studies, respectively. The prevalence of PCP is probably underestimated, as the reports were mainly based on clinical records. An expansion of biological diagnostic methods could make it possible to estimate the exact burden of PCP in Ethiopia.

Childhood pneumonia in low-and-middle-income countries: An update

OBJECTIVES

To review epidemiology, aetiology and management of childhood pneumonia in low-and-middle-income countries.

DESIGN

Review of published English literature between 2013 and 2019.

RESULTS

Pneumonia remains a major cause of morbidity and mortality. Risk factors include young age, malnutrition, immunosuppression, tobacco smoke or air pollution exposure. Better methods for specimen collection and molecular diagnostics have improved microbiological diagnosis, indicating that pneumonia results from several organisms interacting. Induced sputum increases microbiologic yield for Bordetella pertussis or Mycobacterium tuberculosis, which has been associated with pneumonia in high TB prevalence areas. The proportion of cases due to Streptococcus pneumoniae and Haemophilus influenzae b has declined with new conjugate vaccines; Staphylococcus aureus and H. influenzae non-type b are the commonest bacterial pathogens; viruses are the most common pathogens. Effective interventions comprise antibiotics, oxygen and non-invasive ventilation. New vaccines have reduced severity and incidence of disease, but disparities exist in uptake.

CONCLUSION

Morbidity and mortality from childhood pneumonia has decreased but a considerable preventable burden remains. Widespread implementation of available, effective interventions and development of novel strategies are needed.

The aetiology of diarrhoea, pneumonia and respiratory colonization of HIV-exposed infants randomized to breast- or formula-feeding

BACKGROUND

Diarrhoea and pneumonia are common causes of childhood death in sub-Saharan Africa but there are few studies describing specific pathogens.

OBJECTIVES

The study aimed to describe the pathogens associated with diarrhoea, pneumonia and oropharyngeal colonization in children born to HIV-infected women (HIV-exposed infants).

METHODS

The Mashi Study randomized 1200 HIV-infected women and their infants to breastfeed for 6 months with ZDV prophylaxis or formula-feed with 4 weeks of ZDV. Children were tested for HIV by PCR at 1, 4, 7, 9 and 12 months and by ELISA at 18 months. Pre-defined subsets of children were sampled during episodes of diarrhoea (n = 300) and pneumonia (n = 85). Stool was tested for bacterial pathogens, rotavirus and parasites. Children with pneumonia underwent bacterial blood culture, and testing of nasopharyngeal aspirates for viral pathogens by PCR. Oropharyngeal swabs were collected from a consecutive subset of 561 infants at the routine 3-month visit for bacterial culture.

RESULTS

The median age (range) at sampling was 181 days for diarrhoea (0-730) and 140 days for pneumonia (2-551). Pathogens were identified in 55 (18%) children with diarrhoea and 32 (38%) with pneumonia. No differences in pathogens by child HIV status (HIV-infected vs HIV-uninfected) or feeding strategy were identified. Campylobacter was the most common diarrhoeal pathogen (7%). Adenovirus (22%) and other viruses (19%) were the primary pathogens isolated during pneumonias. More formula-fed infants had oropharyngeal colonization by pathogenic Gram-negative bacteria (16.8% vs 6.2%, P = 0.003), which was associated with a non-significant increased risk of pneumonia (OR 2.2, 95% CI 0.8-5.7).

CONCLUSION

A trend toward oropharyngeal bacterial colonization was observed in formula-fed infants. Although viruses were most commonly detected during pneumonia, respiratory colonization by Gram-negative bacteria may have contributed to pneumonia in formula-fed infants.

Chest Radiographic Findings and Outcomes of Pneumonia Among Children in Botswana

BACKGROUND

Chest radiography is increasingly used to diagnose pneumonia in low-income and middle-income countries. Few studies examined whether chest radiographic findings predict outcomes of children with clinically suspected pneumonia in these settings.

METHODS

This is a hospital-based, prospective cohort study of children 1-23 months of age meeting clinical criteria for pneumonia in Botswana. Chest radiographs were reviewed by 2 pediatric radiologists to generate a consensus interpretation using standardized World Health Organization criteria. We assessed whether final chest radiograph classification was associated with our primary outcome, treatment failure at 48 hours, and secondary outcomes.

RESULTS

From April 2012 to November 2014, we enrolled 249 children with evaluable chest radiographs. Median age was 6.1 months, and 58% were male. Chest radiograph classifications were primary endpoint pneumonia (35%), other infiltrate/abnormality (42%) or no significant pathology (22%). The prevalence of endpoint consolidation was higher in children with HIV infection (P = 0.0005), whereas endpoint pleural effusions were more frequent among children with moderate or severe malnutrition (P = 0.0003). Ninety-one (37%) children failed treatment, and 12 (4.8%) children died. Primary endpoint pneumonia was associated with an increased risk of treatment failure at 48 hours (P = 0.002), a requirement for more days of respiratory support (P = 0.002) and a longer length of stay (P = 0.0003) compared with no significant pathology. Primary endpoint pneumonia also predicted a higher risk of treatment failure than other infiltrate/abnormality (P = 0.004).

CONCLUSIONS

Chest radiograph provides useful prognostic information for children meeting clinical criteria for pneumonia in Botswana. These findings highlight the potential benefit of expanded global access to diagnostic radiology services.

Sputum induction improves detection of pathogens in children with cystic fibrosis

BACKGROUND

Sputum induction is a safe, well tolerated means of obtaining lower airway secretions from children with cystic fibrosis (CF), particularly for assessment of airway inflammation but the clinical value in diagnosing outpatient infections has not been extensively studied.

OBJECTIVES

Investigate the success rate and microbiologic yield of induced sputum (IS) compared to oropharyngeal swabs (OP) and expectorated sputum (ES) samples in children with CF, and determine if IS culture results impact treatment.

METHODS

Two cohorts were included in this prospective, longitudinal comparative study. In one cohort, simultaneously collected OP, ES, and IS specimens were obtained from 17 CF children at three visits over 1 year. In the second group, sputum induction was performed in 35 CF subjects at four annual visits, and culture results were compared to their nearest respiratory culture within 4 months. Antimicrobial treatment regimens were captured retrospectively.

RESULTS

Sputum induction was successful in 149 of 158 (94%) visit encounters. Polymicrobial infection (combined P = 0.005) and gram negative organisms (combined P = 0.003) were detected more frequently in IS samples compared to OP, as were the individual pathogens Pseudomonas aeruginosa (combined P = 0.04) and Stenotrophomonas maltophilia (combined P = 0.05). The microbiologic yield of serial IS samples collected over 1 year was stable. IS culture results led to antibiotic changes in 6% of visit encounters. However, based on current practice 13% of visits could have resulted in treatment changes.

CONCLUSIONS

Sputum induction is feasible in the outpatient setting and appears to improve pathogen detection in children with CF.

The expanding role of co-trimoxazole in developing countries

Co-trimoxazole is an inexpensive, broad-spectrum antimicrobial drug that is widely used in developing countries. Before antiretroviral therapy (ART) scale-up, co-trimoxazole prophylaxis reduced morbidity and mortality in adults and children with HIV by preventing bacterial infections, diarrhoea, malaria, and Pneumocystis jirovecii pneumonia, despite high levels of microbial resistance. Co-trimoxazole prophylaxis reduces early mortality by 58% (95% CI 39-71) in adults starting ART. Co-trimoxazole provides ongoing protection against malaria and non-malaria infections after immune reconstitution in ART-treated individuals in sub-Saharan Africa, leading to a change in WHO guidelines, which now recommend long-term co-trimoxazole prophylaxis for adults and children in settings with a high prevalence of malaria or severe bacterial infections. Co-trimoxazole prophylaxis is recommended for HIV-exposed infants from age 4-6 weeks; however, the risks and benefits of co-trimoxazole during infancy are unclear. Co-trimoxazole prophylaxis reduces anaemia and improves growth in children with HIV, possibly by reducing inflammation, either through direct immunomodulatory activity or through effects on the intestinal microbiota leading to reduced microbial translocation. Ongoing trials are now assessing the ability of adjunctive co-trimoxazole to reduce mortality in children after severe anaemia or severe acute malnutrition. In this Review, we discuss the mechanisms of action, benefits and risks, and clinical trials of co-trimoxazole in developing countries.

Use of Induced sputum to determine the prevalence of Pneumocystis jirovecii in immunocompromised children with pneumonia

BACKGROUND

Information on prevalence of Pneumocystis jirovecii pneumonia (PCP) in immunocompromised children with pneumonia in Southeast Asia is limited.

METHODS

Immunocompromised children hospitalized with radiographic pneumonia were investigated for PCP by testing induced sputum by using polymerase chain reaction (PCR).

RESULTS

Ninety-four immunocompromised children (mean age 74.5 ± 43.7 months, boys 69) with pneumonia were investigated for PCP. Underlying disease included solid tumors and hematological malignancy in 57, HIV infection in 14, primary immune deficiency in 11 and other immune deficiency disorders in 12 children. PCR could detect P. jirovecii in 14 children. Prevalence of PCP in HIV-infected children was 43% (6 of 14), renal disease on immunosuppressants 45% (4 of 9), primary immune deficiency 19% (2 of 11) and malignancies on chemotherapy 4% (2 of 57). Three of 14 children died from PCP.

CONCLUSIONS

PCP is responsible for pneumonia in 14% of children with underlying immunocompromised state; PCR on induced sputum improves diagnosis.

Pneumocystis pneumonia in South African children diagnosed by molecular methods

Background

Pneumocystis pneumonia (PCP) is an important cause of hospitalization and mortality in HIV-infected children. However, the incidence of PCP has been underestimated due to poor sensitivity of diagnostic tests. The use of polymerase chain reaction (PCR) for pneumocystis has enabled more reliable diagnosis. This study describes the incidence, clinical features and outcome of PCP in South African children diagnosed using PCR.

Methods

A prospective study of children hospitalised in South Africa with suspected PCP was done from November 2006 to August 2008. Clinical, laboratory and radiological information were collected. Lower respiratory tract specimens were obtained for PCP immunofluorescence (IF), real- time PCR for pneumocystis, bacterial and mycobacterial culture. Nasopharyngeal aspirates were taken for immunofluorescence (IF), real-time PCR for pneumocystis and PCR for respiratory viruses. A blood specimen for bacterial culture and for cytomegalovirus PCR was taken. Children were followed for the duration of their hospitalisation and the outcome was recorded.

Results

202 children [median (interquartile range, IQR) age 3.2 (2.1– 4.6) months] were enrolled; 124 (61.4%) were HIV infected. PCP was identified in 109 (54%) children using PCR, compared to 43 (21%) using IF and Grocott staining (p < 0.0001). Most PCP cases (88, 81%) occurred in HIV-infected children. All 21 cases (19%) occurring in HIV- negative children had another risk factor for PCP. On logistic regression, predictive factors for PCP were HIV infection, lack of fever, high respiratory rate and low oxygen saturation whilst cotrimoxazole prophylaxis was protective (OR 0.24; 95% CI 0.1 to 0.5; p < 0.002). The case fatality of children with PCP was higher than those without PCP (32.1% versus 17.2%; relative risk 1.87; 95% confidence interval (CI) 1.11 – 3.15). Amongst HIV-infected children, a CD4 less than 15% was the only independent predictor of mortality.

Conclusions

The diagnostic yield for PCP is more than 2.5 times higher on PCR than other detection methods. PCP is a very common cause of severe hypoxic pneumonia and is associated with high mortality in HIV-infected African infants.

Humoral immune responses to Pneumocystis jirovecii antigens in HIV-infected and uninfected young children with pneumocystis pneumonia

Background

Humoral immune responses in human immunodeficiency virus (HIV)-infected and uninfected children with Pneumocystis pneumonia (PcP) are poorly understood.

Methods

Consecutive children hospitalized with acute pneumonia, tachypnea, and hypoxia in South Africa were investigated for PcP, which was diagnosed by real-time polymerase chain reaction on lower respiratory tract specimens. Serum antibody responses to recombinant fragments of the carboxyl terminus of Pneumocystis jirovecii major surface glycoprotein (MsgC) were analyzed.

Results

149 children were enrolled of whom 96 (64%) were HIV-infected. PcP occurred in 69 (72%) of HIV-infected and 14 (26%) of HIV-uninfected children. HIV-infected children with PcP had significantly decreased IgG antibodies to MsgC compared to HIV-infected patients without PcP, but had similar IgM antibodies. In contrast, HIV-uninfected children with PcP showed no change in IgG antibodies to MsgC, but had significantly increased IgM antibodies compared to HIV-uninfected children without PCP. Age was an independent predictor of high IgG antibodies, whereas PcP was a predictor of low IgG antibodies and high IgM antibodies. IgG and IgM antibody levels to the most closely related MsgC fragments were predictors of survival from PcP.

Conclusions

Young HIV-infected children with PcP have significantly impaired humoral immune responses to MsgC, whereas HIV-uninfected children with PcP can develop active humoral immune responses. The children also exhibit a complex relationship between specific host factors and antibody levels to MsgC fragments that may be related to survival from PcP.

Pneumocystis jirovecii pneumonia in tropical and low and middle income countries: a systematic review and meta-regression

Objective

Pneumocystis jirovecii pneumonia (PCP), the commonest opportunistic infection in HIV-infected patients in the developed world, is less commonly described in tropical and low and middle income countries (LMIC). We sought to investigate predictors of PCP in these settings.

Design

Systematic review and meta-regression.

Methods

Meta-regression of predictors of PCP diagnosis (33 studies). Qualitative and quantitative assessment of recorded CD4 counts, receipt of prophylaxis and antiretrovirals, sensitivity and specificity of clinical signs and symptoms for PCP, co-infection with other pathogens, and case fatality (117 studies).

Results

The most significant predictor of PCP was per capita Gross Domestic Product, which showed strong linear association with odds of PCP diagnosis (p<0.0001). This was not explained by study design or diagnostic quality. Geographical area, population age, study setting and year of study also contributed to risk of PCP. Co-infection was common (444 episodes/1425 PCP cases), frequently with virulent organisms. The predictive value of symptoms, signs or simple tests in LMIC settings for diagnosis of PCP was poor. Case fatality was >30%; treatment was largely appropriate. Prophylaxis appeared to reduce the risk for development of PCP, however 24% of children with PCP were receiving prophylaxis. CD4 counts at presentation with PCP were usually <200×10^3/ml.

Conclusions

There is a positive relationship between GDP and risk of PCP diagnosis. Although failure to diagnose infection in poorer countries may contribute to this, we also hypothesise that poverty exposes at-risk patients to a wide range of infections and that the relatively non-pathogenic P. jirovecii is therefore under-represented. As LMIC develop economically they eliminate the conditions underlying transmission of virulent infection: P. jirovecii, ubiquitous in all settings, then becomes a greater relative threat.

Effects of cotrimoxazole prophylactic treatment on adverse health outcomes among HIV-exposed, uninfected infants

BACKGROUND

The World Health Organization guidelines recommend cotrimoxazole prophylactic treatment (CPT) for all HIV-exposed infants from age 6 weeks to the cessation of breastfeeding and the exclusion of HIV infection. There are limited data on the effects of CPT among this population of infants. We examined the effects of CPT on adverse health outcomes among HIV-exposed infants during the first 36 weeks of life using data from the Breastfeeding, Antiretrovirals and Nutrition study, a large clinical trial of antiretroviral drugs given to the mother or infant for the prevention of HIV transmission during breastfeeding.

METHODS

For the analysis, we assigned a status of CPT-exposed to infants who were participating in the study after the CPT program started. We estimated unadjusted and adjusted hazard ratios for the effect of CPT status on time to incident malaria, severe illness or death, anemia, and weight-for-age Z score < -2.0. Participation in the study was limited to focus exclusively on HIV-exposed, uninfected infants.

RESULTS

The hazard ratio for the effect of CPT on incident malaria was 0.35 (95% confidence interval: 0.21, 0.57) during the first 10 weeks of CPT exposure and 0.93 (95% confidence interval: 0.67, 1.29) for the remaining 20 weeks. CPT was not associated with the other outcomes examined.

CONCLUSIONS

CPT offered temporary protection against malaria among HIV-exposed, uninfected infants. However, CPT offered no protection against anemia, low weight for age or the collapsed outcome of severe illness or death.

Clinical conditions associated with PCP in children

Pneumocystis jirovecii is a leading cause of opportunistic infections among the immune compromised. During the 1980s, attention focused on patients with HIV, however, with the advent of anti-retroviral therapy, we wished to revisit the question of underlying diseases associated with Pneumocystis pneumonia in children. We identified 80 cases from 1986 to 2006 and performed a retrospective chart review to identify clinical characteristics for each of the cases. HIV was the single most common associated underlying condition seen in this cohort, accounting for 39% of the cases overall, however, it was seen in just 15% of the cases since 1998. Transplant recipients and oncology patients together comprised another 39% of the cases, with 9% of cases attributed to primary immune deficiency and another 9% of cases associated with less well-recognized causes of susceptibility. This study documents the ongoing need for vigilance to diagnose Pneumocystis pneumonia in less well-recognized clinical scenarios.

Procedures for collection of induced sputum specimens from children

In most settings, sputum is not routinely collected for microbiological diagnosis from children with lower respiratory disease. To evaluate whether it is feasible and diagnostically useful to collect sputum in the Pneumonia Etiology Research for Child Health (PERCH) study, we reviewed the literature on induced sputum procedures. Protocols for induced sputum in children were collated from published reports and experts on respiratory disease and reviewed by an external advisory group for recommendation in the PERCH study. The advisory group compared 6 protocols: 4 followed a nebulization technique using hypertonic saline, and 2 followed a chest or abdomen massage technique. Grading systems for specimen quality were evaluated. Collecting sputum from children with lower respiratory tract illness is feasible and is performed around the world. An external advisory group recommended that sputum be collected from children hospitalized with severe and very severe pneumonia who participate in the PERCH study provided no contraindications exist. PERCH selected the nebulization technique using hypertonic saline.

Improved detection of Pneumocystis jirovecii in upper and lower respiratory tract specimens from children with suspected pneumocystis pneumonia using real-time PCR: a prospective study

Background

Pneumocystis pneumonia (PCP) is a major cause of hospitalization and mortality in HIV-infected African children. Microbiologic diagnosis relies predominantly on silver or immunofluorescent staining of a lower respiratory tract (LRT) specimens which are difficult to obtain in children. Diagnosis on upper respiratory tract (URT) specimens using PCR has been reported useful in adults, but data in children are limited. The main objectives of the study was (1) to compare the diagnostic yield of PCR with immunofluorescence (IF) and (2) to investigate the usefulness of upper compared to lower respiratory tract samples for diagnosing PCP in children.

Methods

Children hospitalised at an academic hospital with suspected PCP were prospectively enrolled. An upper respiratory sample (nasopharyngeal aspirate, NPA) and a lower respiratory sample (induced sputum, IS or bronchoalveolar lavage, BAL) were submitted for real-time PCR and direct IF for the detection of Pneumocystis jirovecii. A control group of children with viral lower respiratory tract infections were investigated with PCR for PCP.

Results

202 children (median age 3.3 [inter-quartile range, IQR 2.2 - 4.6] months) were enrolled. The overall detection rate by PCR was higher than by IF [180/349 (52%) vs. 26/349 (7%) respectively; p < 0.0001]. PCR detected more infections compared to IF in lower respiratory tract samples [93/166 (56%) vs. 22/166 (13%); p < 0.0001] and in NPAs [87/183 (48%) vs. 4/183 (2%); p < 0.0001]. Detection rates by PCR on upper (87/183; 48%) compared with lower respiratory tract samples (93/166; 56%) were similar (OR, 0.71; 95% CI, 0.46 - 1.11). Only 2/30 (6.6%) controls were PCR positive.

Conclusion

Real-time PCR is more sensitive than IF for the detection of P. jirovecii in children with PCP. NPA samples may be used for diagnostic purposes when PCR is utilised. Wider implementation of PCR on NPA samples is warranted for diagnosing PCP in children.

Chest radiographic presenting features and radiographic progression of pneumocystis pneumonia in South African children

PURPOSE

To describe the radiographic features of PCP in South African children, including the progression of changes and the impact of HIV-infection and respiratory co-infections.

METHODS

A paediatric radiologist blinded to clinical details retrospectively reported the chest radiographs of children diagnosed with PCP at a South Africa paediatric hospital between January 2003 and June 2006 inclusive. Radiographic features were correlated with clinical findings and compared using Fisher's exact test and Wilcoxon's ranks-sum test. Institutional ethics approval was obtained.

RESULTS

Of 113 cases of PCP, 110 (97.3%) had presenting and 96 (84.9%) follow-up radiographs; 88 (82%) were HIV-infected; 65 (59%) had respiratory co-infection; 48 (43%) died in hospital. The commonest presenting radiographic findings were increased lung volumes (n = 86; 78%) and diffuse parenchymal opacification (n = 70; 64%); 89 (92.7%) ultimately progressed to diffuse alveolar opacification. Median time to maximum pulmonary opacification was 72 hours (inter-quartile range (IQR): 24-144 hrs). Pulmonary interstitial emphysema (PIE) developed in 33 patients (30%). There was no significant difference in the radiographic features of PCP when comparison was made between i) HIV-infected and -uninfected children, ii) those with and without respiratory co-infection and iii) fatal cases and survivors (P > 0.05 in all cases).

CONCLUSION

Increased lung volumes and PIE should be recognised as features of PCP in South African children. HIV-infection and respiratory co-infections do not influence the radiographic features of PCP in our setting.

Systematic review on the etiology and antibiotic treatment of pneumonia in human immunodeficiency virus-infected children

BACKGROUND

Community-acquired pneumonia (CAP) is a leading cause of morbidity and mortality in human immunodeficiency virus (HIV)-infected children.

OBJECTIVES AND METHODS

A systematic review of studies that were published between January 1990 and February 2009 on the etiology and antimicrobial or adjunctive systemic management of CAP in HIV-infected children.

RESULTS

Pneumocystis jirovecii had the strongest association with HIV infection, with a summary odds ratio of 10.1 (95% confidence interval [CI], 17.7-62.1) and 9.1 (95% CI, 2.5-33.1) in antemortem and postmortem studies, respectively. Cytomegalovirus was strongly associated with HIV positivity among fatal cases of pneumonia (summary odds ratio = 14.4 [95% CI, 6.7-30.8]). There was a trend toward a greater prevalence of Staphylococcus aureus (odds ratio, 2.5; 95% CI, 0.95-6.4) in HIV-infected children. Major limitations identified included substantial methodological heterogeneity across studies, limited sensitivity of assays for diagnosing bacterial pneumonia, and studies primarily being undertaken in the absence of antiretroviral treatment or cotrimoxazole prophylaxis. No a priori-planned randomized controlled trials on antimicrobial management of CAP in HIV-infected children were identified.

CONCLUSIONS

A World Health Organization panel used this review as well as analysis of risks and benefits to revise recommendations for antimicrobial treatment of CAP. Ampicillin plus gentamicin or ceftriaxone is now recommended as first-line empiric regimens for treating severe and very severe CAP in HIV-infected children. In addition, treatment with cloxacillin or vancomycin is recommended in settings with a high incidence of methicillin-resistant S. aureus, and particularly if clinical or microbiological evidence of S. aureus pneumonia exist. Further studies in HIV-infected children on CAP etiology and antibiotic treatment are required in the era of antiretroviral treatment.

Cost-effectiveness analysis of diagnostic options for pneumocystis pneumonia (PCP)

Background

Diagnosis of Pneumocystis jirovecii pneumonia (PCP) is challenging, particularly in developing countries. Highly sensitive diagnostic methods are costly, while less expensive methods often lack sensitivity or specificity. Cost-effectiveness comparisons of the various diagnostic options have not been presented.

Methods and Findings

We compared cost-effectiveness, as measured by cost per life-years gained and proportion of patients successfully diagnosed and treated, of 33 PCP diagnostic options, involving combinations of specimen collection methods [oral washes, induced and expectorated sputum, and bronchoalveolar lavage (BAL)] and laboratory diagnostic procedures [various staining procedures or polymerase chain reactions (PCR)], or clinical diagnosis with chest x-ray alone. Our analyses were conducted from the perspective of the government payer among ambulatory, HIV-infected patients with symptoms of pneumonia presenting to HIV clinics and hospitals in South Africa. Costing data were obtained from the National Institutes of Communicable Diseases in South Africa. At 50% disease prevalence, diagnostic procedures involving expectorated sputum with any PCR method, or induced sputum with nested or real-time PCR, were all highly cost-effective, successfully treating 77–90% of patients at $26–51 per life-year gained. Procedures using BAL specimens were significantly more expensive without added benefit, successfully treating 68–90% of patients at costs of $189–232 per life-year gained. A relatively cost-effective diagnostic procedure that did not require PCR was Toluidine Blue O staining of induced sputum ($25 per life-year gained, successfully treating 68% of patients). Diagnosis using chest x-rays alone resulted in successful treatment of 77% of patients, though cost-effectiveness was reduced ($109 per life-year gained) compared with several molecular diagnostic options.

Conclusions

For diagnosis of PCP, use of PCR technologies, when combined with less-invasive patient specimens such as expectorated or induced sputum, represent more cost-effective options than any diagnostic procedure using BAL, or chest x-ray alone.

Impact of human immunodeficiency virus infection on the etiology and outcome of severe pneumonia in Malawian children

BACKGROUND

HIV infection is a major risk factor for death in childhood pneumonia in HIV-endemic regions. Improved case management and preventive strategies require better understanding of the impact of HIV on causes, clinical presentation, and outcome.

METHODS

A prospective, clinical descriptive study of Malawian infants and children with severe pneumonia included blood culture and nasopharyngeal aspiration for diagnosis of pneumocystis pneumonia (PcP). A select group with consolidation on chest radiograph, and without severe hypoxia or hyperinflation, also had lung aspirate taken for culture and identification of bacterial deoxyribonucleic acid by real-time polymerase chain reaction (PCR).

RESULTS

There were 327 study patients with a median age of 11 months (range, 2 months-14 years). HIV prevalence was 51%. There were 58 cases of confirmed bacterial pneumonia, of which the most common bacterial isolates were Streptococcus pneumoniae and Salmonella typhimurium. Of the 54 lung aspirates, only 2 were positive on culture but 27 were positive for bacterial deoxyribonucleic acid by PCR. PcP was confirmed in 16 patients, and was associated with young age, severe hypoxia, HIV infection, and a very poor outcome. The overall case-fatality rate was 10% despite presumptive therapy for PcP and routine broad-spectrum antibiotic treatment appropriate for local antimicrobial susceptibility data. Most of the deaths occurred in infants of 2 to 6 months of age and PcP was associated with 57% of these deaths.

CONCLUSIONS

PcP is a major barrier in reducing the case-fatality rate of severe pneumonia in infants of HIV-endemic communities. The use of PCR on lung aspirate specimens greatly increased the diagnostic yield.

A randomized controlled trial of intermittent compared with daily cotrimoxazole preventive therapy in HIV-infected children

OBJECTIVE

Cotrimoxazole preventive therapy (CPT) reduces morbidity and mortality in HIV-infected children. The WHO recommends prolonged daily CPT for HIV-infected infants and children. In adults, intermittent CPT has been associated with less adverse events than daily, with increased tolerability and equal efficacy. We investigated the efficacy and tolerability of intermittent CPT compared with daily CPT in HIV-infected children over a 5-year period.

DESIGN

A prospective randomized controlled study.

METHODS

HIV-infected children aged at least 8 weeks were randomized to thrice weekly or daily CPT. Outcome measures were mortality, bacterial infections, hospitalizations and adverse events.

RESULTS

Three hundred and twenty-four children (median age 23 months) were followed for 672 child-years; 165 (51%) were randomized to intermittent CPT. Most children (287, 89%) were Centers for Disease Control and Prevention clinical category B or C; 207 (64%) received HAART during the study. Mortality (53 deaths, 16%) was similar in the intermittent CPT compared with the daily CPT group {24 (14%) vs. 29 (18%), hazard ratio 0.75 [95% confidence interval (CI) 0.44-1.29]}. The predominant causes of death in both groups were sepsis (17, 32%), pneumonia (13, 25%) or diarrhoea (8, 15%). Intermittent CPT was associated with more bacteraemias [incidence rate ratio 2.36 (95% CI 1.21-4.86)]. Children receiving intermittent CPT also spent more days in hospital [incidence rate ratio 1.15 (95% CI 1.04-1.28)]. The rate of serious adverse events was similar between groups [incidence rate ratio 1.07 (95% CI 0.58-2.02)].

CONCLUSION

Intermittent CPT was associated with more invasive bacterial disease than daily CPT, but survival was similar. Both regimens were well tolerated. On balance, daily CPT remains preferable to intermittent therapy for HIV-infected children.

CMV pneumonia in HIV-infected ventilated infants

BACKGROUND

The contributing role of cytomegalovirus (CMV) in infants treated for Pneumocystis jiroveci pneumonia (PJP) is unknown. High dose steroids used in the treatment of PJP may further immunocompromise these infants contributing to the development of CMV pneumonia.

AIM

The aim of this study was to determine the role of CMV pneumonia in infants being ventilated for suspected PJP.

METHODS

In this prospective study HIV infected infants being treated with trimethoprim-sulfamethoxazole (TMP/SMX) and ventilated for suspected PJP were included if they had not responded to treatment. Open lung biopsy was performed if there was no improvement in ventilatory requirements.

RESULTS

Twenty-five HIV positive infants with a mean age of 3.3 months were included. Lung biopsy was performed in 17 (68%) and post-mortem lung tissue was obtained in 8 (32%). After evaluation of the histology, immunohistochemistry, and viral cultures from lung tissue, the most likely causes of pneumonia were: CMV and PJP dual infection 36% (n = 9), CMV pneumonia 36% (n = 9), and PJP 24% (n = 6). The pp65 test for CMV antigen was falsely negative in 24%. The mean blood CD4 count was 287/microl. There was an association between the CD4 lymphocyte status and the final diagnosis, with the CMV and PJP group (CD4 110/microl) having the lowest CD4 status (P = 0.0128). Pediatric Intensive Care Unit (PICU) mortality was 72% (n = 18) and in hospital mortality 88%.

CONCLUSION

Of the ventilated infants failing to respond to treatment, 72% had histologically confirmed CMV pneumonia, probably accounting for the high mortality in this cohort. The incidence of CMV disease in HIV infected infants being ventilated for severe pneumonia warrants that ganciclovir is used empirically until CMV disease is excluded. The role of lung biopsy in these circumstances needs to be researched.

Impact of HIV on standard case management for severe pneumonia in children

It is estimated that 2 million children under 5 years of age die from pneumonia each year and that half of these deaths occur in sub-Saharan Africa. Over 85% of the more than 2.3 million children living with HIV worldwide reside in sub-Saharan Africa. HIV infection is likely to have a major impact on current recommendations for the standard case management of pneumonia in children and is the rationale for undertaking this review of published studies. The studies identified indicate an overall sixfold (range 2.5-13.5-fold) increase in pneumonia-related fatality in HIV-infected compared with HIV-uninfected African infants and children. They are more likely to have disease due to mixed infection and from a wider range of pathogens including Pneumocystis pneumonia, TB and cytomegalovirus. Scaling-up of the implementation of strategies that prevent HIV and Pneumocystis pneumonia remains an important strategy to reduce the burden of HIV-related pneumonia in the region. Research is urgently required to address the most effective pneumonia case management strategy in HIV-infected infants and children.

Pneumocystis pneumonia in South African children with and without human immunodeficiency virus infection in the era of highly active antiretroviral therapy

BACKGROUND

Pneumocystis pneumonia (PCP) is a major cause of hospitalization and mortality in human immunodeficiency virus (HIV)-infected African children.

AIM

The aim of this study was to investigate the incidence and outcome of PCP in South African children living in a high HIV-prevalence area in the context of a free, available antiretroviral therapy program.

METHODS

Sequential children hospitalized with hypoxic pneumonia were prospectively enrolled from November 2006 to August 2008. Sociodemographic, historical, clinical, and outcome data were collected. A nasopharyngeal aspirate and lower respiratory tract sample (induced sputum or bronchoalveolar lavage) were submitted for PCP immunofluorescence. Lower respiratory tract samples were also investigated for bacterial, mycobacterial, and viral pathogens.

RESULTS

A total of 202 children were enrolled; 124 (61.4%) were HIV-infected; 34 (16.8%) were HIV-exposed but uninfected and 44 (21.8%) were HIV-unexposed. Among HIV-exposed children, 70 (44.3%) had participated in the Prevention of Mother to Child Transmission program, but only 18.4% were taking trimethoprim-sulfamethoxazole prophylaxis. PCP occurred in 43 children (21.3%) of whom 33 (76.7%) were HIV-infected. The case fatality of children with PCP was higher than those without PCP (39.5% vs. 21.4%; relative risk, 1.85; 95% confidence interval, 1.15-2.97; P = 0.01).

CONCLUSIONS

PCP is a common cause of hypoxic pneumonia and mortality in HIV-infected South African infants. Underuse of the Prevention of Mother to Child Transmission program and failure to institute trimethoprim-sulfamethoxazole prophylaxis in HIV-exposed children identified through the program are important obstacles to reducing PCP incidence.

High prevalence of dihydropteroate synthase mutations in Pneumocystis jirovecii isolated from patients with Pneumocystis pneumonia in South Africa

Pneumocystis jirovecii pneumonia (PCP) is an important cause of morbidity and mortality in immunocompromised patients. Sulfa-containing drugs are used for the treatment and prophylaxis of PCP. Mutations in the P. jirovecii fas gene, which encodes dihydropteroate synthase (DHPS), are associated with prior exposure to sulfa drugs, and their appearance suggests the emergence of variants with reduced sulfa susceptibility. The present study examined the prevalence of DHPS mutations in P. jirovecii strains isolated from South African patients with PCP. P. jirovecii infection was investigated by immunofluorescence microscopy and quantitative real-time PCR with respiratory specimens from 712 patients (93% of whom were >15 years of age) with suspected PCP consecutively received for the detection of P. jirovecii over 1 year. PCR amplification and sequencing of the DHPS fas gene was attempted with DNA from the P. jirovecii-positive samples. P. jirovecii infection was confirmed by immunofluorescence microscopy in 168/712 (24%) of the patients. Carriage of the fungus was revealed by real-time PCR in 17% of the patients with negative microscopy results. The P. jirovecii fas gene was successfully amplified from specimens from 151 patients and sequenced. Mutations resulting in the Thr55Ala and/or Pro57Ser amino acid substitution were detected in P. jirovecii strains from 85/151 (56%) patients. The high frequency of PCP episodes with P. jirovecii harboring DHPS mutations in South Africa indicates that populations of this fungus are evolving under the considerable selective pressure exerted by sulfa-containing antibiotics. These results, similar to previous observations of sulfa drug resistance in bacterial populations, underscore the importance of the rational use of sulfa medications either prophylactically against PCP or for the treatment of other infections.

Improved detection of Pneumocystis jirovecii infection in a tertiary care reference hospital in India

We prospectively examined 143 clinical samples from 115 patients including both HIV infected (n=53) and HIV uninfected immunocompromized (n=62) patients, with lung infiltrates and with clinical features suggestive of Pneumocystis carinii pneumonia/ PneumoCystis Pneumonia (PcP), using both microscopic techniques as well as PCR assay. Clinical samples in the present study consisted of bronchoalveolar lavage (BAL), tracheal aspirate (TA), nasopharyngeal aspirate (NPA), sputum and gastric aspirate (GA). Another group of 21 individuals with other respiratory diseases not compatible with PcP served as control during the study period of 15 months. Overall, P. jirovecii positivity rate by PCR was 12.17% (14/115 patients) compared to 3.4% (4/115) by microscopy. None of the specimens in the control group was positive by any of the techniques used. All PCR negative patients including cases and controls showed no evidence of PcP. After resolution of the discrepant results upon review of the clinical data, the sensitivity and specificity were 100% and 99%, respectively, for PCR and 30.7% and 100%, respectively, for microscopy by GMS staining. Thus, our data support the significance of PCR assay for confirming and improving the diagnosis of PcP in high-risk patients.

Clinical profile of 516 children affected by HIV in a tertiary care centre in northern India: 14 years of experience

Increasing numbers of children affected by HIV are being recognised in northern India. The present study aimed to evaluate the clinical profile of 516 children affected by HIV at the Pediatric Allergy and Immunology Unit, Advanced Pediatric Center, Postgraduate Institute of Medical Education and Research, Chandigarh, India, during the period January 1994 to May 2008. In total, 454 children (327 boys and 127 girls) infected by HIV were analysed. The median age at presentation was 54 months. Of these children, 401 (88.3%) acquired the infection vertically and 26 (5.7%) acquired it through transfusion of blood/blood products. Moreover, 156 children (34.4%) were asymptomatic at presentation to hospital. Common clinical features included fever (36.6%), respiratory infections (31.7%), lymphadenopathy (30.0%), hepatosplenomegaly (21.8%) and diarrhoea (18.1%); 299 children (65.9%) were malnourished. Triple drug antiretroviral therapy was initiated in 205 children. Children receiving such therapy showed significant improvement in clinical and immunological parameters. Furthermore, follow-up rates improved markedly following free supply of the drug. Therapy was very well tolerated. To conclude, physicians looking after children need to be familiar with the varying clinical presentation of HIV infection. To the best of our knowledge, this is the largest paediatric series on HIV infection from a single centre from any developing country.

18-month occurrence of severe events among early diagnosed HIV-infected children before antiretroviral therapy in Abidjan, Côte d'Ivoire: a cohort study

Objective

To assess the 18-month field effectiveness on severe events of a pediatric package combining early HIV-diagnosis and targeted cotrimoxazole prophylaxis in HIV-infected children from age six-week before the antiretroviral era, in Abidjan, Côte d'Ivoire.

Methods

Data from two consecutive prevention of HIV mother-to-child transmission programs were compared: the ANRS 1201/1202 Ditrame-Plus cohort (2001–2005) and the pooled data of the ANRS 049a Ditrame randomized trial and its following open-labeled cohort (1995–2000), used as a reference group. HIV-infected pregnant women ≥ 32–36 weeks of gestation were offered a short-course peri-partum antiretroviral prophylaxis (ZDV in Ditrame, and ZDV ± 3TC+single-dose (sd) NVP in Ditrame-Plus). Neonatal prophylaxis was provided in Ditrame-Plus only: 7-day ZDV and sdNVP 48–72 h after birth. A 6-week pediatric HIV-RNA diagnosis was provided on-line in the Ditrame-Plus while it was only oriented on clinical symptoms in Ditrame. Six-week HIV-infected children received a daily cotrimoxazole prophylaxis in Ditrame-Plus while no prophylaxis was provided in Ditrame. The determinants of severe events (death or hospitalization > 1 day) were assessed in a Cox regression model.

Results

Between 1995 and 2003, 98 out of the 1121 live-births were diagnosed as HIV-infected in peri-partum: 45 from Ditrame-Plus and 53 from Ditrame. The 18-month Kaplan-Meier cumulative probability of presenting a severe event was 66% in Ditrame-Plus (95% confidence interval [95%CI]: 50%–81%) and 77% in Ditrame (95%CI: 65%–89%), Log Rank test: p = 0.47. After adjustment on maternal WHO clinical stage, maternal death, 6-week pediatric viral load, birth-weight, and breastfeeding exposure, the 18-month risk of severe event was lower in Ditrame-Plus than in Ditrame (adjusted Hazard Ratio (aHR): 0.55, 95%CI: 0.3–1.1), although the difference was not statistically significant; p = 0.07). Maternal death was the only variable determinant of the occurrence of severe events in children (aHR: 3.73; CI: 2.2–11.2; p = 0.01).

Conclusion

Early cotrimoxazole from 6 weeks of age in HIV-infected infants seemed to reduce probability of severe events but the study lacked statistical power to prove this. Even with systematic cotrimoxazole prophylaxis, infant morbidity and mortality remained high pointing towards a need for early pediatric HIV-diagnosis and antiretroviral treatment in Africa.

Radiographic features of paediatric pneumocystis pneumonia -- a historical perspective

AIM

To determine differences between the plain radiographic features of paediatric pneumocystis pneumonia (PCP) recorded before the emergence of human immunodeficiency virus (HIV) in 1982 and those documented in the HIV era. To establish differences in the radiographic features of PCP documented in HIV-infected children in developed and developing countries.

METHOD

A Medline search of articles was conducted from 1950 to 2006, using the terms "pneumocystis pneumonia in children" and "chest radiographic features" or "bilateral opacification" or "lobar consolidation" or "asymmetrical opacification" or "pneumatocoeles" or "cavities" or "pneumothorax" or "pneumomediastinum" or "pleural effusion" or "mediastinal adenopathy" or "nodules" or "normal chest radiography". Appropriate articles were retrieved, radiological data extracted, reference lists examined and hand searches of referenced articles conducted.

RESULTS

Diffuse bilateral "ground-glass" or alveolar pulmonary opacification, which may show some asymmetry, has been consistently documented as the commonest radiographic finding in childhood PCP throughout the period under review. The less common radiological features of PCP in children are similar to those in adults. In developed countries, PCP-related pulmonary air cysts have been reported at an earlier age in HIV-infected children, compared with uninfected children. PCP-related air cysts, pneumothorax, and pneumomediastinum have been reported in children in developed but not in developing countries.

CONCLUSION

The radiological features of paediatric PCP documented before the HIV epidemic are similar to those recorded in the HIV era. Further study of the determinants of the uncommon radiographic features in children is warranted.

Child mortality according to maternal and infant HIV status in Zimbabwe

BACKGROUND

HIV causes substantial mortality among African children but there is limited data on how this is influenced by maternal or infant infection status and timing.

METHODS

Children enrolled in the ZVITAMBO trial were divided into 5 groups: those born to HIV-negative mothers (NE, n = 9510), those born to HIV-positive mothers but noninfected (NI, n = 3135), those infected in utero (IU, n = 381), those infected intrapartum (IP, n = 508), and those infected postnatally (PN, n = 258). Their mortality was estimated.

RESULTS

Two-year mortality was 2.9% (NE infants), 9.2% (NI), 67.5% (IU), 65.1% (IP), and 33.2% (PN). Between 8 weeks and 6 months, mortality in IU infants quintupled (from 309 to 1686/1000 c-y). The median time from infection to death was 208, 380, and >500 days for IU, IP, and PN infants, respectively. Among NI children, advanced maternal disease was predictive of mortality. Acute respiratory infection was the major cause of death.

CONCLUSIONS

Perinatally infected infants are at particular risk of death between 2 and 6 months: cotrimoxazole prophylaxis and early pediatric HAART should be scaled up. Uninfected infants of infected mothers have at least twice the mortality risk of infants born to uninfected mothers: all HIV-exposed infants should be targeted with child survival interventions. HIV-positive mothers with more advanced disease are not only more likely to infect their infants, but their infants are more likely to die, whether infected or not: provision of antiretroviral treatment to pregnant and lactating women is an urgent need for both mothers and their children.

Care and treatment of HIV-infected children in Africa: issues and challenges at the district hospital level

More than 90% of pediatric HIV infection occurs in sub-Saharan Africa and 75% of these children currently die before their fifth birthday. Most HIV-infected children in Africa rely on district hospitals for HIV treatment, but insufficient attention has been paid to improving HIV/AIDS care at this level. Considerable confusion exists about optimal use of combination antiretroviral treatment, prophylaxis for opportunistic infections and other rational healthcare interventions that can greatly improve the quality of life for these children. A simple and inexpensive infant HIV diagnostic assay and alternative laboratory markers of pediatric HIV disease progression would be highly beneficial. Routine anthropometric and neurodevelopmental assessments could help guide initiation and monitoring of antiretroviral therapy. Even in the absence of antiretroviral therapy, interventions such as immunizations, provision of micronutrients and nutrition counseling, prevention and treatment of opportunistic as well as endemic infections (such as helminths and malaria) can substantially reduce pediatric HIV-related morbidity and mortality. The need for pain relief, palliative care, counseling and emotional support is often underestimated. Surmounting the sense of hopelessness by providing district healthcare workers with training in basic pediatric HIV/AIDS care is an urgent priority.

Sensitivity and specificity of nested and real-time PCR for the detection of Pneumocystis jiroveci in clinical specimens

A polymerase chain reaction (PCR)-based test for Pneumocystis jiroveci (formerly Pneumocystis carinii f. sp. hominis) might be an alternative to histologic diagnoses of P. jiroveci pneumonia (PCP). However, previously developed nested PCR methods tend to have low specificities (high false-positive rates). In this study, nested and quantitative real-time PCR methods for the amplification of the P. jiroveci DHPS (dihydropteroate synthase) gene were evaluated in a variety of stored clinical samples from Spain, South Africa, and Brazil. The sensitivities of both assays were high, ranging from 62.5% to 100% depending on the type of specimen. In a subset of 71 microscopically confirmed PCP cases and 70 negative cases, the sensitivities and specificities were 94% and 81% for nested PCR and 94% and 96% for real-time PCR, respectively. Real-time PCR has a statistically significantly better specificity than nested PCR (P = .015) and is likely to generate fewer false positives.

Prevalences of Pneumocystis jiroveci, Mycobacterium tuberculosis and Streptococcus pneumoniae infection in children with severe pneumonia, in a tertiary referral hospital in northern Tanzania

At the Kilimanjaro Christian Medical Centre, a tertiary referral hospital in northern Tanzania, both the number of paediatric cases of lower respiratory-tract infection (LRTI) and the associated mortality increased between 2000 and 2001. Molecular diagnostic tools were used to enhance the identification of the pathogens responsible for this perceived increase. All 72 children aged between 2 and 60 months who were admitted with LRTI over a 3-month period were enrolled in the study. Induced sputum was collected from each child and, if the parents consented, the subjects were also tested for HIV. The sputum samples were each checked for bacteria by culture and, in amplification assays, for the DNA of Pneumocystis jiroveci, Mycobacterium tuberculosis and Streptococcus pneumoniae. Twenty-two (50%) of the 44 children tested for HIV had HIV-1 antibodies. Although only two children, both aged <6 months, were found PCR-positive for P. jiroveci, and only one was found positive for M. tuberculosis, 46 (including one of those found positive for P. jiroveci and the child found positive for M. tuberculosis) were found PCR-positive for S. pneumoniae. It therefore appears that most paediatric cases of LRTI who present at the hospital are attributable to S. pneumoniae, and that infections with this pathogen are entirely responsible for the observed increase in the incidence of LTRI in the local children. The increase seen in LRTI-associated mortality among the children may be the result of pneumococcal antibiotic resistance.

Determinants of Survival Without Antiretroviral Therapy After Infancy in HIV-1-Infected Zambian Children in the CHAP Trial

BACKGROUND

There are few data on predictors of HIV progression in untreated children in resource-limited settings.

METHODS

Children with HIV Antibiotic Prophylaxis (CHAP) was a randomized trial comparing cotrimoxazole prophylaxis with placebo in HIV-infected Zambian children. The prognostic value of baseline characteristics was investigated using Cox models.

RESULTS

Five hundred fourteen children aged 1 to 14 (median 5.5) years contributed 607 years follow-up (maximum 2.6 years). Half were boys, and in 67%, the mother was the primary carer; at baseline, median CD4 percentage was 11% and weight was less than third percentile in 67%. One hundred sixty-five children died (27.2 per 100 years at risk; 95% confidence interval 23.3-31.6). Low weight-for-age, CD4 percentage, hemoglobin, mother as primary carer, current malnutrition, and previous hospital admissions for respiratory tract infections or recurrent severe bacterial infections were independent predictors of poorer survival, whereas oral candidiasis predicted poorer survival only when baseline CD4 percentage was not considered. Mortality rates per 100 child years of 44.5 (37.2-53.2), 14.7 (10.9-19.8), and 2.3 (0.3-16.7) were associated with new World Health Organization stages 4, 3, and 1/2, respectively, applied retrospectively; very low weight-for-age was the only staging feature for 42% of stage 4 children.

CONCLUSIONS

Malnutrition and hospitalizations for respiratory/bacterial infections predict mortality independent of immunosuppression, suggesting that they capture HIV- and non-HIV-related mortality, whereas oral candidiasis is a proxy for immunosuppression.

Clinical indicators of Pneumocystis jiroveci pneumonia (PCP) in South African children infected with the human immunodeficiency virus

BACKGROUND

Pneumocystis pneumonia (PCP) caused by Pneumocystis jiroveci is common in HIV-infected children, producing substantial morbidity and mortality. Initiation of timely, effective therapy depends on clinical identification of children with PCP.

OBJECTIVE

To develop a clinical decision rule to diagnose PCP in HIV-infected children for use where diagnostic resources are limited.

METHODS

Analysis of data collected during a prospective incidence study of the etiology, features, and outcome of HIV-infected children hospitalized with pneumonia.

RESULTS

Four clinical variables were independently associated with a diagnosis of PCP in multivariate analysis: age < 6 months (OR 15.6; 95% CI 2.4-99.8; p = 0.004), respiratory rate > 59 breaths/min (OR 8.1; 95% CI 1.5-53.2; p = 0.018), arterial percentage hemoglobin oxygen saturation (SaO2) < or = 92% (OR 5.1; 95% CI 1.0-26.1; p = 0.052) and absence of history of vomiting (OR 11.2; 95% CI 1.9-68.0; p = 0.008). The sensitivity and specificity of diagnosing PCP with any two or more of these variables were 1.00 (95% CI 0.74-1.00) and 0.49 (95% CI 0.39-0.59), respectively. Diagnosing PCP with three or more of the indicators had a decreased sensitivity of 0.75 (95% CI 0.43-0.95) and increased specificity of 0.90 (95% CI 0.83-0.95).

CONCLUSION

Empirical anti-pneumocystis therapy should be considered in HIV-infected infants presenting with tachypnea, hypoxia and absence of vomiting.

Cotrimoxazole prophylaxis for opportunistic infections in children with HIV infection

BACKGROUND

The majority of children with HIV infection live in low-income countries without access to antiretroviral drugs. The prevention and early treatment of opportunistic infections are the mainstay of their medical management. Cotrimoxazole is cheap and effective against a wide range of organisms, including Pneumocystis jiroveci pneumonia (PCP), which is an important cause of death and illness in the first year of life. It is safe with relatively few side effects. Diagnosis of HIV in children is complicated by the presence of maternal antibodies in early life. Providing prophylaxis based initially on maternal status is one possible solution. However, routine prophylactic treatment is difficult to deliver in low-resource settings, and could also lead to increased resistance to the drug.

OBJECTIVES

To assess the effects of routinely administered cotrimoxazole on death and illness episodes in children with HIV infection, and in infants of HIV-infected mothers.

SEARCH STRATEGY

We searched the Cochrane HIV/AIDS registry, MEDLINE, the Cochrane Controlled Trials Register, LILACS, AIDSLINE, AIDSTRIALS and AIDSDRUGS databases, and proceedings and abstracts from AIDS and TB conferences (search date Feb 2005). We checked reference lists of pertinent articles, and contacted pharmaceutical companies and experts in the field.

SELECTION CRITERIA

Randomised or quasi-randomised trials comparing routinely administered cotrimoxazole versus placebo or no treatment in children (age less than 15 years) with HIV infection, or children less than 18 months with HIV infected mothers.

DATA COLLECTION AND ANALYSIS

Two reviewers independently assessed trial eligibility and quality. Where data were incomplete or unclear trial authors were contacted for further details.

MAIN RESULTS

One study was identified that fulfilled the inclusion criteria. It studied 534 children with HIV infection in Lusaka, Zambia. The study was conducted in an area of high bacterial resistance to cotrimoxazole (60-80%). A reduction in mortality of 33% was seen in the cotrimoxazole group as compared to placebo, relative risk 0.67 (95% CI 0.53 - 0.85). There was also a beneficial effect on hospitalisation, relative risk 0.77 (95% CI 0.62 - 0.96). There was no difference in adverse events between groups, and the beneficial effect was seen across all ages and CD4%.

AUTHORS' CONCLUSIONS

A single trial has shown a beneficial effect from the use of cotrimoxazole prophylaxis in HIV infected children in Zambia. It must be decided whether this can be extrapolated to other resource-poor settings.

Respiratory tract infections in children in developing countries

Acute respiratory infections are the main cause of morbidity worldwide, and pneumonia represents one of the main causes of death in children younger than the age of 5 years in developing countries. Several risk factors for acquiring respiratory infections in developing countries, such as poverty, restricted family income, low parental education level, low birth weight, malnutrition, and lack of breastfeeding, have been described. Another important factor in recent years that has aggravated the problem of acute respiratory infections in developing countries is the human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS) pandemic. In developing countries, identifying the etiology is difficult and World Health Organization recommends making the diagnosis of pneumonia based on clinical parameters. The diagnosis and suitable treatment administered by primary healthcare workers, particularly in rural areas, is part of the strategy to prevent mortality. Finally, it is important that industrialized countries support the economic growth of the developing countries to improve their healthcare system and to ensure that performed research studies will give benefits to their populations.

Carbon loading of alveolar macrophages in adults and children exposed to biomass smoke particles

Exposure to carbonaceous particles from biomass burning is associated with increased respiratory morbidity in both women and children in the developing world. However, the amount of carbon reaching lower airway cells has not been determined in these populations. Alveolar macrophages (AM) remove inhaled particulate matter (PM), and are implicated in the pathogenesis of PM-induced lung disease. In this study, we aimed to compare AM carbon loading in women and children exposed to biomass PM in Gondar, Ethiopia, with individuals exposed to fossil-fuel PM in the developed world (Leicester, UK). To achieve these aims, we sampled AM from Ethiopian mothers and children, and from UK adults and children using induced sputum (IS). AM were imaged under light microscopy, and the total two-dimensional surface area of carbon within each AM determined by image analysis. AM containing carbon were detected in all subjects. The total surface area of carbon per AM was higher in Ethiopian women (n=10) compared with UK adults (n=10, median 9.19 vs. 0.71 microm2/AM, p=0.0002). Similarly, the total surface area of carbon per AM was higher in Ethiopian children (n=10) compared with UK children (n=10, 3.32 vs. 0.44 microm2/AM, p=0.0002). However, loading in Ethiopian children was lower than paired maternal levels (3.32 vs. 9.19 microm2/AM, p=0.011). We conclude that analysis of AM obtained by induced sputum is a practical way of quantifying natural exposure of the lower airway to carbonaceous particles from the burning of biomass fuels.

Sepsis predisposition in children with human immunodeficiency virus

OBJECTIVE

To review predisposition to sepsis in children infected with human immunodeficiency virus (HIV) in the era of highly active antiretroviral therapy (HAART).

DESIGN

Summary of the literature with review by experts in the field.

RESULTS

In industrialized regions, new diagnoses of vertically acquired HIV infection are falling due to perinatal interventions. Provision of HAART has resulted in an enlarging cohort of clinically stable HIV-infected children, with low viral loads and normal CD4 T-lymphocyte counts. Access to HAART in "developed" countries has markedly decreased the rate of progression to acquired immunodeficiency syndrome, the prevalence of organ-specific complications of HIV, the risk of recurrent sepsis, and the high early childhood mortality from HIV infection. There are currently no data on whether initiation of HAART during acute sepsis reduces short-term morbidity or mortality. Undiagnosed, antiretroviral-naive, HIV-infected infants still present sporadically with opportunistic infections such as Pneumocystis jiroveci and cytomegalovirus pneumonia. HIV-infected children have a greater burden of disease due to viral, bacterial, and fungal sepsis, and the case fatality rate for nonopportunistic infections may be greater than in non-HIV-infected children. In "developing" countries, with limited access to HAART, the natural history of HIV infection has altered very little, with the majority of infected children dying from either opportunistic or nonopportunistic disease before 3 yrs of age.

CONCLUSION

Pediatric HIV infection is not a homogeneous condition in the era of HAART. Susceptibility to sepsis, morbidity, and mortality differ according to stage of disease, access to HAART, and virologic and immunologic response to treatment. These issues should be considered if HIV-infected children are to be enrolled and stratified in clinical trials.

Co-trimoxazole as prophylaxis against opportunistic infections in HIV-infected Zambian children (CHAP): a double-blind randomised placebo-controlled trial

BACKGROUND

No trials of co-trimoxazole (trimethoprim-sulfamethoxazole) prophylaxis for HIV-infected adults or children have been done in areas with high levels of bacterial resistance to this antibiotic. We aimed to assess the efficacy of daily co-trimoxazole in such an area.

METHODS

We did a double-blind randomised placebo-controlled trial in children aged 1-14 years with clinical features of HIV infection in Zambia. Primary outcomes were mortality and adverse events possibly related to treatment. Analysis was by intention to treat.

FINDINGS

In October, 2003, the data and safety monitoring committee recommended early stopping of the trial. 541 children had been randomly assigned; seven were subsequently identified as HIV negative and excluded. After median follow-up of 19 months, 74 (28%) children in the co-trimoxazole group and 112 (42%) in the placebo group had died (hazard ratio [HR] 0.57 [95% CI 0.43-0.77], p=0.0002). This benefit applied in children followed up beyond 12 months (n=320, HR 0.48 [0.27-0.84], test for heterogeneity p=0.60) and across all ages (test for heterogeneity p=0.82) and baseline CD4 counts (test for heterogeneity p=0.36). 16 (6%) children in the co-trimoxazole group had grade 3 or 4 adverse events compared with 18 (7%) in the placebo group. These events included rash (one placebo), and a neutrophil count on one occasion less than 0.5x10(9)/L (16 [6%] co-trimoxazole vs seven [3%] placebo, p=0.06). Pneumocystis carinii was identified by immunofluorescence in only one (placebo) of 73 nasopharyngeal aspirates from children with pneumonia.

INTERPRETATION

Our results suggest that children of all ages with clinical features of HIV infection should receive co-trimoxazole prophylaxis in resource-poor settings, irrespective of local resistance to this drug.

Prevalence of dihydropteroate synthase mutants in HIV-infected South African children with Pneumocystis jiroveci pneumonia

BACKGROUND

Pneumocystis jiroveci (formerly Pneumocystis carinii) pneumonia (PCP) is a major cause of mortality in human immunodeficiency virus (HIV)-infected infants in Africa, but the prevalence of mutations in the gene encoding dihydropteroate synthase (DHPS) in isolates from Africa has not been reported.

METHODS

This study investigated the prevalence of DHPS mutations in P. jiroveci isolates from South African HIV-infected children with PCP by amplifying DNA using 2 different polymerase chain reactions.

RESULTS

P. jiroveci DNA from 30 respiratory specimens was amplified; 26 specimens (86.7%) contained wild-type DHPS alleles. Of the 4 samples (13.3%) with DHPS mutations, 2 contained a homogenous population with single DHPS mutations, 1 contained a homogenous population with 2 DHPS mutations, and the fourth contained a heterogenous population of organisms with both wild-type and single-mutant DHPS genotypes. Only 1 child was receiving trimethoprim-sulphamethoxazole (TMP-SMZ) prophylaxis; this patient was infected with wild-type P. jiroveci. The mortality rate (overall, 20 [66.7%] of 30 children) was not significantly different between children infected with wild-type P. jiroveci (17 [65.4%] of 26) and those infected with mutant strains (3 [75%] of 4; P=.8).

CONCLUSIONS

DHPS mutations are uncommon in P. jiroveci isolates from South Africa. However, increasing use of TMP-SMZ prophylaxis may result in widespread development of mutations.

Pneumonia in HIV-infected and HIV-uninfected children in developing countries

PURPOSE OF REVIEW

Pneumonia is a leading cause of illness and death in children younger than 5 years in developing countries, accounting for approximately 20% of childhood deaths. The HIV epidemic has sharply increased the incidence, severity, and mortality of childhood pneumonia in the developing world, particularly in sub-Saharan Africa. This article reviews recent findings on the epidemiology, clinical features, and management of HIV-infected and -uninfected children with pneumonia in developing countries.

RECENT FINDINGS

Bacterial infection remains a major cause of pneumonia mortality; in HIV-infected children, a broader spectrum of pathogens including gram-negative infections and Pneumocystis jiroveci occurs. Mycobacterium tuberculosis is an important cause of acute pneumonia among children from high tuberculosis prevalence areas. Use of case management guidelines substantially reduces neonatal, infant, and under-5 mortality and pneumonia-specific mortality in developing countries. New advances in therapy include the use of short-course antibiotics and high-dose amoxicillin twice daily for ambulatory treatment of HIV-negative children with pneumonia. New preventive interventions include the development of conjugate vaccines against Streptococcus pneumoniae and Haemophilus influenzae, but these are not widely affordable nor available in developing countries. Despite a lower efficacy in HIV-infected children, these vaccines still protect against disease in a significant proportion of children. Available preventive interventions including micronutrient supplementation with zinc and vitamin A, and immunization as contained in the WHO Expanded Program of Immunization can substantially reduce the burden of childhood pneumonia.

SUMMARY

Urgent measures to implement existing available, effective interventions for prevention and treatment of childhood pneumonia and achieve high coverage rates in developing countries are needed.

Impact of HIV on childhood respiratory illness: differences between developing and developed countries

The main differences of the impact of HIV on childhood respiratory illness between developed and developing countries, and particularly some countries in Africa, are the scale of the problem and the lack of resources to address problems of prevention, diagnosis, and management. Recent data from HIV-infected African children are reviewed and show that the pattern of respiratory disease in these children is not markedly different to the pattern that was reported from the USA and Europe prior to the use of antiretroviral therapy and routine Pneumocystis jiroveci pneumonia (PCP) prophylaxis for HIV-exposed infants. Bacterial pneumonia is very common in all age groups. PCP and cytomegalovirus (CMV) are especially common in infants, and lymphoid interstitial pneumonitis (LIP) is common in older children. One difference is that pulmonary tuberculosis (PTB) is relatively more common in HIV-infected African children. This is likely to reflect the higher prevalence of smear-positive PTB in the region and therefore of exposure/infection compared to developed countries. Autopsy studies have provided a lot of useful data, but more prospective clinical and intervention studies from different parts of the region are needed in order to improve clinical diagnosis and management.

Pneumocystoses graves en réanimation pédiatrique étude rétrospective 1980–2002

OBJECTIVE

The objective of this study was to ascertain the clinical and epidemiological characteristics of Pneumocystis carinii pneumonia (PCP) cases admitted to the Pediatric Intensive Care Unit (PICU).

PATIENTS AND METHODS

A retrospective study was carried out for the 10 PCP cases admitted to the PICU from 1980 to 2002. The variables studied were: age, sex, PRISM, underlying diseases, immunological status, clinical manifestations, radiology, response to therapy and clinical follow up.

RESULTS

Age of the patients varied between 5 months and 15 years and 4 months and there were 7 females and 3 males. Underlying diseases included: AIDS (3 cases), renal transplant (2 cases), West syndrome (1 case), cancer (4 cases). All presented an acute respiratory failure and 8/10 needed mechanical ventilation (mean duration: 14 days). All were treated by trimethoprim-sulfamethoxazole and 6/10 received steroids. Only one child died.

CONCLUSION

PCP is rare and affects mainly immunocompromised children who exhibit ARDS. Steroids treatment is now considered as an useful therapeutic adjuvant. A preventive treatment should be administered to children at risk.

Sputum induction as a diagnostic tool for community-acquired pneumonia in infants and young children from a high HIV prevalence area

Sputum induction is a standard diagnostic procedure to identify pathogens in lower respiratory tract secretions in adults with pneumonia, but has rarely been studied or used in infants and young children. Our aim was to determine the usefulness of induced sputum (IS) as a diagnostic method for infants and children hospitalized with community-acquired pneumonia (CAP) in a high HIV prevalence area. Children hospitalized for CAP were prospectively enrolled over a year. IS was obtained by nebulization with hypertonic (5%) saline, physiotherapy, and suctioning. Sputum was submitted for bacterial and mycobacterial culture and P. carinii detection. Gastric lavages (GLs) were done for M. tuberculosis culture; a nasopharyngeal aspirate (NPA) was obtained for bacterial culture and P. carinii detection. IS was obtained in 210 children (median age, 7 (25th to 75th percentile, 3-18) months); 138 (66%) were HIV-infected; 148 (70%) were receiving supplemental oxygen. Bacteria were isolated from 101 (50%) IS and 141 (70%) NPA paired specimens (P < 0.001). A significantly higher rate of S. aureus, H. influenzae, M. catarrhalis, and S. pneumoniae was found in NPAs compared to IS; this pattern was particularly evident in HIV-infected children. M. tuberculosis was cultured from sputum in 19 patients (9%); GLs performed in 142 children were positive in only 9 (6%). The difference (95% confidence interval) between yields for M. tuberculosis from culture of IS compared to GL was 4.3% (95% CI, 0-5.6%; P = 0.08). P. carinii was identified from IS in 12 (5.7%) children; all corresponding NPAs were negative. Seven (3%) children could not tolerate sputum induction. Side effects included increased coughing in 4%, epistaxis in 3%, and wheezing responsive to bronchodilators in 1%. In conclusion, induced sputum is a useful and safe diagnostic procedure in infants and children with CAP from a high HIV prevalence area.

HIV and respiratory infections in children

Respiratory disease is a frequent cause of morbidity and mortality in children infected with human immunodeficiency virus (HIV). This review highlights recent data and developments that relate to the impact of HIV on respiratory infections particularly in African children. Autopsy and clinical studies continue to show that bacterial pneumonia and Pneumocystis jiroveci pneumonia (PCP) are common respiratory infections and causes of death in regions where antiretroviral therapy and PCP prophylaxis are not routinely practiced. Recent studies of Zambian and South African children showed that pulmonary tuberculosis is more common in HIV-infected children than was previously recognized. The trial of bacterial conjugate vaccines in Johannesburg will provide important information of efficacy in an HIV endemic population. Prospective clinical descriptive and intervention studies are needed from different regions to guide clinical management and prevention of respiratory infections in HIV-infected children living in resource-poor countries.